[Federal Register Volume 76, Number 111 (Thursday, June 9, 2011)]
[Proposed Rules]
[Pages 33924-33965]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-13910]



[[Page 33923]]

Vol. 76

Thursday,

No. 111

June 9, 2011

Part IV





Department of the Interior





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Fish and Wildlife Service



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50 CFR Part 17



Endangered and Threatened Wildlife and Plants; 12-Month Finding on a 
Petition to List Abronia ammophila, Agrostis rossiae, Astragalus 
proimanthus, Boechera (Arabis) pusilla, and Penstemon gibbensii as 
Threatened or Endangered; Proposed Rule

  Federal Register / Vol. 76 , No. 111 / Thursday, June 9, 2011 / 
Proposed Rules  

[[Page 33924]]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[FWS-R6-ES-2011-0023; MO 92210-0-0008-B2]


Endangered and Threatened Wildlife and Plants; 12-Month Finding 
on a Petition To List Abronia ammophila, Agrostis rossiae, Astragalus 
proimanthus, Boechera (Arabis) pusilla, and Penstemon gibbensii as 
Threatened or Endangered

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of 12-month petition finding.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 
12-month finding on a petition to list Abronia ammophila (Yellowstone 
sand verbena), Agrostis rossiae (Ross' bentgrass), Astragalus 
proimanthus (precocious milkvetch), Boechera (Arabis) pusilla (Fremont 
County rockcress or small rockcress), and Penstemon gibbensii (Gibbens' 
beardtongue) as threatened or endangered, and to designate critical 
habitat under the Endangered Species Act of 1973, as amended (Act). 
After review of all available scientific and commercial information, we 
find that listing A. ammophila, A. rossiae, A. proimanthus, and P. 
gibbensii is not warranted at this time. However, we ask the public to 
submit to us any new information that becomes available concerning the 
threats to A. ammophila, A. rossiae, A. proimanthus, and P. gibbensii 
or their habitats at any time. After a review of all the available 
scientific and commercial information, we find that listing B. pusilla 
as threatened or endangered is warranted. However, currently listing B. 
pusilla is precluded by higher priority actions to amend the Federal 
Lists of Endangered and Threatened Wildlife and Plants. Upon 
publication of this 12-month petition finding, we will add B. pusilla 
to our candidate species list. We will develop a proposed rule to list 
B. pusilla as our priorities allow. We will make any determinations on 
critical habitat during development of the proposed listing rule. In 
any interim period, we will address the status of the candidate taxon 
through our annual Candidate Notice of Review.

DATES: The finding announced in this document was made on June 9, 2011.

ADDRESSES: This finding is available on the Internet at http://www.regulations.gov at Docket Number FWS-R6-ES-2011-0023. Supporting 
documentation used in preparing this finding is available for public 
inspection, by appointment, during normal business hours at the U.S. 
Fish and Wildlife Service, Wyoming Ecological Services Field Office, 
5353 Yellowstone Road, Suite 308A, Cheyenne, WY 82009. Please submit 
any new information, materials, comments, or questions concerning this 
finding to the above address.

FOR FURTHER INFORMATION CONTACT: R. Mark Sattelberg, Field Supervisor, 
Wyoming Ecological Services Field Office (see ADDRESSES); by telephone 
at 307-772-2374; or by facsimile at 307-772-2358. If you use a 
telecommunications device for the deaf (TDD), please call the Federal 
Information Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Background

    Section 4(b)(3)(B) of the Act (16 U.S.C. 1531 et seq.), requires 
that, for any petition to revise the Federal Lists of Endangered and 
Threatened Wildlife and Plants that contains substantial scientific or 
commercial information that listing the species may be warranted, we 
make a finding within 12 months of the date of receipt of the petition. 
In this finding, we will determine that the petitioned action is: (1) 
Not warranted, (2) warranted, or (3) warranted, but the immediate 
proposal of a regulation implementing the petitioned action is 
precluded by other pending proposals to determine whether species are 
threatened or endangered, and expeditious progress is being made to add 
or remove qualified species from the Federal Lists of Endangered and 
Threatened Wildlife and Plants. Section 4(b)(3)(C) of the Act requires 
that we treat a petition for which the requested action is found to be 
warranted but precluded as though resubmitted on the date of such 
finding, that is, requiring a subsequent finding to be made within 12 
months. We must publish these 12-month findings in the Federal 
Register.

Previous Federal Actions

    Federal action for Agrostis rossiae and Astragalus proimanthus 
began as a result of section 12 of the original Act, which directed the 
Secretary of the Smithsonian Institution to prepare a report on plants 
considered to be endangered, threatened, or extinct in the United 
States. This report, designated as House Document No. 94-51, was 
presented to Congress on January 9, 1975. That document lists A. 
rossiae as a threatened species and A. proimanthus as an endangered 
species (House Document 94-51, pp. 57, 90, 163). On July 1, 1975, we 
published a notice in the Federal Register (40 FR 27823) accepting the 
Smithsonian Institution report as a petition within the context of 
section 4(c)(2) (petition provisions are now found in section 4(b)(3) 
of the Act), and giving notice of the Service's intention to review the 
status of the plant taxa listed therein.
    As a result of that review, we published a proposed rule on June 
16, 1976, in the Federal Register (41 FR 24523) to determine endangered 
status pursuant to section 4 of the Act for approximately 1,700 
vascular plant taxa, including Astragalus proimanthus. This list of 
plant taxa was assembled based on comments and data received by the 
Smithsonian Institution and the Service in response to House Document 
No. 94-51 and the July 1, 1975, Federal Register publication. General 
comments received in response to the 1976 proposal are summarized in an 
April 26, 1978, Federal Register publication (43 FR 17909). In 1978, 
amendments to section 4(f)(5) of the Act required that all proposals 
over 2 years old be withdrawn. However, proposals already over 2 years 
old were given a 1-year grace period. On December 10, 1979, we 
published a notice in the Federal Register (44 FR 70796) withdrawing 
the portion of the June 16, 1976, proposal that had not been made 
final. This removed both A. proimanthus and Agrostis rossiae from 
proposed status, but retained both species as candidate plant taxa that 
``may qualify for listing under the Act.''
    On December 15, 1980, we published a current list of those plant 
taxa native to the United States being considered for listing under the 
Act; this identified both Agrostis rossiae and Astragalus proimanthus 
as category 1 taxa (45 FR 82480). The Service defined category 1 taxa 
as a taxonomic group for which we presently had sufficient information 
on hand to support the biological appropriateness of these taxa being 
listed as threatened or endangered species (45 FR 82480). On November 
28, 1983, A. rossiae was lowered to a category 2 taxon ``currently 
under review,'' whereas A. proimanthus was moved to the ``taxa no 
longer under review'' list, and given a 3C rank, indicating the species 
was more abundant or widespread than previously believed or not 
subjected to any identifiable threat (48 FR 53640). We defined category 
2 taxa as those for which we had information at that time that 
indicated proposing to list was possibly appropriate, but for which 
substantial data on biological

[[Page 33925]]

vulnerability and threat(s) was not currently known or on file to 
support proposed rules. Boechera (formerly Arabis) pusilla and 
Penstemon gibbensii were added as category 2 taxa during the same 
review (48 FR 53640). These four species retained the same ranking for 
the subsequent review on September 27, 1985 (50 FR 39526). The February 
21, 1990, list kept A. rossiae, B. pusilla, and P. gibbensii as 
category 2 taxa, and reverted A. proimanthus back to a category 2 taxon 
(55 FR 6184).
    The September 30, 1993, review changed the status of Boechera 
pusilla to a category 1 species (58 FR 51144). This review added a 
``status trend'' column. Each species was identified as increasing (I), 
stable (S), declining (D), or unknown (U). The 1993 review added 
Abronia ammophila and assigned it a 2U rank, moved Boechera pusilla up 
to a 1D rank, and listed Agrostis rossiae as 2U, Astragalus proimanthus 
as 2S, and Penstemon gibbensii as 2U (58 FR 51144).
    On February 28, 1996, we proposed discontinuing the designation of 
category 2 species as candidates due to the lack of sufficient 
information to justify issuance of a proposed rule (61 FR 7596). This 
proposal included eliminating candidate status for four of the five 
species addressed in this finding; only Boechera pusilla was proposed 
to remain a candidate (61 FR 7596). This policy change was finalized on 
December 5, 1996, stating that the listing of category 2 species was 
not needed because of other lists already maintained by other entities 
such as Federal and State agencies (61 FR 64481).
    On September 19, 1997, we published a notice of review that 
retained Boechera pusilla as a candidate species (62 FR 49398). 
However, on October 25, 1999, we published a notice of review that 
indicated our intent to remove several species, including B. pusilla, 
from the list of candidate species because evidence suggested that 
these taxa were either more abundant than previously believed or that 
the taxa were not subject to the degree of threats sufficient to 
warrant continuance of candidate status, issuance of a proposed 
listing, or a final listing (64 FR 57534). The change of status for B. 
pusilla was finalized on October 20, 2000, on the basis that regulatory 
mechanisms and changes to management of the associated land reduced or 
eliminated the threats facing B. pusilla and ensured the survival and 
conservation of this species (65 FR 63044).
    On July 30, 2007, we received a formal petition dated July 24, 
2007, from Forest Guardians (now WildEarth Guardians), requesting that 
we: (1) Consider all full species in our Mountain-Prairie Region ranked 
as G1 or G1G2 by the organization NatureServe, except those that are 
currently listed, proposed for listing, or candidates for listing; and 
(2) list each species as either threatened or endangered. The petition 
identified 206 species as petitioned entities, including the 5 species 
we address in this status review. A species ranking of G1 is defined as 
a species that is critically imperiled across its entire range (or 
global range) (NatureServe 2010b, p. 3). A ranking of G1G2 means the 
species is either ranked as a G1 or a G2 species, with G2 defined as 
imperiled across its entire range (NatureServe 2010b, pp. 3-4). The 
petition incorporated all analysis, references, and documentation 
provided by NatureServe in its online database at http://www.natureserve.org/ into the petition. The petition clearly identified 
itself as a petition and included the identification information, as 
required in 50 CFR 424.14(a). We sent a letter to the petitioners, 
dated August 24, 2007, acknowledging receipt of the petition and 
stating that, based on preliminary review, we found no compelling 
evidence to support an emergency listing for any of the species covered 
by the petition.
    On March 19, 2008, WildEarth Guardians filed a complaint (1:08-CV-
472-CKK) indicating that the Service failed to comply with its 
mandatory duty to make a preliminary 90-day finding on their two 
multiple-species petitions--one for mountain-prairie species and one 
for southwest species. We subsequently published two initial 90-day 
findings on January 6, 2009 (74 FR 419), and February 5, 2009 (74 FR 
6122). The February 5, 2009, finding determined that there was not 
substantial scientific or commercial information indicating that 
listing 165 of the 206 petitioned species in the mountain-prairie 
region may be warranted (74 FR 6122). Two additional species were 
evaluated in a January 6, 2009, 90-day finding (74 FR 419), and no 
determination was made on whether substantial information had been 
presented on the remaining 39 species included in the petition (74 FR 
6122). The 5 species covered in this 12-month finding were among the 
remaining 39 species. An additional species was determined to qualify 
for candidate status (73 FR 75175; December 10, 2008). On March 13, 
2009, the Service and WildEarth Guardians filed a stipulated settlement 
in the District of Columbia Court, agreeing that the Service would 
submit to the Federal Register a finding as to whether WildEarth 
Guardians' petitions present substantial information indicating that 
the petitioned actions may be warranted for the remaining 38 mountain-
prairie species by August 9, 2009.
    On June 18, 2008, we received a petition from WildEarth Guardians 
dated June 12, 2008, to emergency list 32 species under the 
Administrative Procedure Act and the Endangered Species Act. Of those 
32 species, 11 were included in the July 24, 2007, petition to be 
listed on a non-emergency basis. Although the Act does not provide for 
a petition process for an interested person to seek to have a species 
emergency listed, section 4(b)(7) of the Act authorizes the Service to 
issue emergency regulations to temporarily list a species. In a letter 
dated July 25, 2008, we stated that the information provided in both 
the 2007 and 2008 petitions and in our files did not indicate that an 
emergency situation existed for any of the 11 species. The Service's 
decisions whether to exercise its authority to issue emergency 
regulations to temporarily list a species are not judicially 
reviewable. See Fund for Animals v. Hogan, 428 F.3d 1059 (DC Cir. 
2005).
    On August 18, 2009, we published a notice of 90-day finding (74 FR 
41649) on the remaining 38 species from the petition to list 206 
species in the mountain-prairie region of the United States as 
threatened or endangered under the Act. We found that the petition 
presented substantial scientific and commercial information for 29 of 
the 38 species, indicating that listing may be warranted for those 
species. The 5 species we address in this 12-month finding were 
included within these 29 species. We also opened a 60-day public 
comment period to allow all interested parties an opportunity to 
provide information on the status of the 29 species (74 FR 41649). The 
public comment period closed on October 19, 2009. We received 224 
public comments. Of these, 38 specifically addressed Abronia ammophila, 
Agrostis rossiae, Astragalus proimanthus, Boechera pusilla, and 
Penstemon gibbensii. All information received has been carefully 
considered in this finding. This notice constitutes the 12-month 
finding on 5 of the 206 species identified in WildEarth Guardians' 
petition dated July 24, 2007, to list Abronia ammophila, Agrostis 
rossiae, Astragalus proimanthus, Boechera pusilla, and Penstemon 
gibbensii as threatened or endangered.

[[Page 33926]]

Summary of Procedures for Determining the Listing Status of Species

Review of Status Based on Five Factors
    Section 4 of the Act (16 U.S.C. 1533) and implementing regulations 
(50 CFR part 424) set forth procedures for adding species to, removing 
species from, or reclassifying species on the Federal Lists of 
Endangered and Threatened Wildlife and Plants. Under section 4(a)(1) of 
the Act, a species may be determined to be endangered or threatened 
based on any of the following five factors:
    (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range;
    (B) Overutilization for commercial, recreational, scientific, or 
educational purposes;
    (C) Disease or predation;
    (D) The inadequacy of existing regulatory mechanisms; or
    (E) Other natural or manmade factors affecting its continued 
existence.
    In making these findings, information pertaining to each species in 
relation to the five factors provided in section 4(a)(1) of the Act is 
discussed below. In considering what factors might constitute threats 
to a species, we must look beyond the exposure of the species to a 
particular factor to evaluate whether the species may respond to the 
factor in a way that causes actual impacts to the species. If there is 
exposure to a factor and the species responds negatively, the factor 
may be a threat, and during the status review, we attempt to determine 
how significant a threat it is. The threat is significant if it drives 
or contributes to the risk of extinction of the species such that the 
species warrants listing as endangered or threatened as those terms are 
defined by the Act. However, the identification of factors that could 
impact a species negatively may not be sufficient to compel a finding 
that the species warrants listing. The information must include 
evidence sufficient to suggest that the potential threat has the 
capacity (i.e., it should be of sufficient magnitude and extent) to 
affect the species' status such that it meets the definition of 
endangered or threatened under the Act.
Findings
Distinct Population Segments
    After considering the five factors, we assess whether each species 
is threatened or endangered throughout all of its range. Generally, we 
next consider in our findings whether a distinct vertebrate population 
segment (DPS) or any significant portion of the species' range meets 
the definition of endangered or is likely to become endangered in the 
foreseeable future (threatened). Section 3(16) of the Act defines a 
species to include only a vertebrate species as a DPS. Therefore, the 
Service's Policy Regarding the Recognition of Distinct Vertebrate 
Population Segments Under the Endangered Species Act (DPS Policy) (61 
FR 4722; February 7, 1996) is not applicable to plants and no 
population segments under the review could qualify as DPSs under the 
Act. Although the Service's DPS Policy is not applicable to plants, we 
do determine in our findings whether a plant species is threatened or 
endangered in a significant portion of its range.
Significant Portion of the Range
    In determining whether a species is threatened or endangered in a 
significant portion of its range, we first identify any portions of the 
range of the species that warrant further consideration. The range of a 
species can theoretically be divided into portions an infinite number 
of ways. However, there is no purpose to analyzing portions of the 
range that are not reasonably likely to be both (1) significant and (2) 
threatened or endangered. To identify only those portions that warrant 
further consideration, we determine whether there is substantial 
information indicating that: (1) The portions may be significant, and 
(2) the species may be in danger of extinction there or likely to 
become so within the foreseeable future. In practice, a key part of 
this analysis is whether the threats are geographically concentrated in 
some way. If the threats to the species are essentially uniform 
throughout its range, no portion is likely to warrant further 
consideration. Moreover, if any concentration of threats applies only 
to portions of the species' range that are not significant, such 
portions will not warrant further consideration.
    If we identify portions that warrant further consideration, we then 
determine whether the species is threatened or endangered in these 
portions of its range. Depending on the biology of the species, its 
range, and the threats it faces, the Service may address either the 
significance question or the status question first. Thus, if the 
Service considers significance first and determines that a portion of 
the range is not significant, the Service need not determine whether 
the species is threatened or endangered there. Likewise, if the Service 
considers status first and determines that the species is not 
threatened or endangered in a portion of its range, the Service need 
not determine if that portion is significant. However, if the Service 
determines that both a portion of the range of a species is significant 
and the species is threatened or endangered there, the Service will 
specify that portion of the range as threatened or endangered under 
section 4(c)(1) of the ESA.

Evaluation of the Status of Each of the Five Plant Species

    For each of the five species, we provide a description of the 
species and its life-history and habitat, an evaluation of listing 
factors for that species, and our finding that the petitioned action is 
warranted or not for that species. We follow these descriptions, 
evaluations, and findings with a discussion of the priority and 
progress of our listing actions.

Species Information for Abronia ammophila

Species Description

    Abronia ammophila is a low-growing, mat-forming perennial herb 
(Clark et al. 1989, p. 7; Fertig 1994, unpaginated; (National Park 
Service (NPS) 1999b, p. 3; Fertig 2000b, unpaginated; Saunders and 
Sipes 2006, p. 76). A. ammophila is a highly restricted endemic 
(occurring only in one location or region) to the Yellowstone Plateau 
(NPS 1999a, p. 1). In addition to the common name of Yellowstone sand 
verbena, A. ammophila has been called Tweedy's sand verbena (Clark et 
al. 1989, p. 7; Marriott 1993, p. 1) and Wyoming sand verbena 
(Integrated Taxonomic Information System 2010a, unpaginated).
    Abronia ammophila has a large taproot (primary root that grows 
vertically downward, not highly branched) that can be over 0.5 meter 
(m) (1.6 feet (ft)) in length, which helps the plant root into the 
loose sand (Whipple 1999, p. 3; Whipple 2002, p. 257; Saunders and 
Sipes 2004, p. 9). Its stems can grow up to 2 to 4 decimeters (dm) 
(0.66 to 1.31 ft) in length; however, this plant is only 2.5 to 10.2 
centimeters (cm) (1 to 4 inches (in.)) tall (Rydberg 1900, p. 137; 
Galloway 1975, p. 344; Fertig 1994, unpaginated; NPS 1999b, p. 3; 
Fertig 2000b, unpaginated; NPS 2000, unpaginated). A. ammophila is 
covered by sticky glands, which result in the plants being covered with 
sand (Coulter and Nelson 1909, p. 175; NPS 1999b, p. 3; NPS 2000, 
unpaginated; Whipple 2002, pp. 257-258; Saunders and Sipes 2006, p. 
76). The leaf blades are succulent (fleshy) and oval or diamond-shaped 
with smooth edges (Fertig 1994, unpaginated; NPS 1999b, p. 3).

[[Page 33927]]

    The flowers of Abronia ammophila are whitish to light pink or light 
green and grow in a capitulum (head-like group of flowers) typically 
containing 4 to 21 flowers (Saunders and Sipes 2006, p. 79). The 
flowers are hermaphroditic (possessing both male and female 
reproductive organs) (Saunders and Sipes 2004, p. 9; 2006, p. 76). As 
with other members of the Nyctaginaceae (the Four O'Clock) family, A. 
ammophila lacks true petals (Saunders and Sipes 2004, p. 9; 2006, p. 
76).

Discovery and Taxonomy

    Frank Tweedy made the first collection of Abronia ammophila in 
1885; however, he labeled it as Abronia villosa (desert sand verbena). 
The collection was from the sandy beaches on the north side of 
Yellowstone Lake at the mouth of Pelican Creek (Tweedy 1886, p. 59). A. 
villosa is a common purple-flowered species of the American southwest 
(Whipple 2002, p. 256). In 1900, Per Axel Rydberg determined that 
Tweedy's sample was sufficiently different from other Abronia to 
warrant recognition as a unique species; he named it Abronia arenaria 
(coastal sand verbena) (NPS 1999b, p. 2; Whipple 1999, p. 3; 2002, p. 
256). However, the name A. arenaria had previously been used (NPS 
1999b, p. 2; Whipple 1999, p. 2; 2002, p. 256). E.L. Greene proposed 
the name A. ammophila for the Yellowstone sand verbena species (Greene 
1900 as cited in Whipple 2002, p. 256).
    The name Abronia ammophila was formally recognized (Coulter and 
Nelson 1909, p. 175); however, midway through the 20th century it was 
combined with Abronia fragrans (snowball sand verbena), a widespread 
western species (Hitchcock et al. 1964 and Despain 1975 as cited in 
Whipple 2002, p. 257). In 1975, a study of the Abronia genus determined 
that the Yellowstone species was unique (Galloway 1975, p. 344; NPS 
1999b, p. 3; Whipple 2002, p. 257). Plant material collected from scrub 
communities of sandy hills near Big Piney, Sublette County, Wyoming, 
also was included under A. ammophila (Galloway 1975, p. 344, NPS 1999b, 
p. 3; Whipple 2002, p. 257). Further examination revealed that the 
specimens from Sublette County are actually Abronia mellifera (white 
sand verbena) (Marriott 1993, pp. 6, 9; Fertig 1994, unpaginated).
    Abronia ammophila is a member of the New World plant family 
Nyctaginaceae that typically lives in warmer climates, such as deserts 
and tropical areas (NPS 2000, unpaginated). The genus Abronia contains 
approximately 20 to 30 species (NPS 1999b, p. 2, Flora of North America 
2010a, unpaginated). Most Abronia occur in the western United States 
and Mexico, but some extend into southern Canada and east into the 
Great Plains and Texas (NPS 1999b, p. 2). A. ammophila is similar to 
Abronia mellifera (Fertig 1994, unpaginated) and Abronia fragrans 
(Flora of North America 2010, unpaginated). We recognize A. ammophila 
as a valid species and a listable entity.

Biology and Life History

    Abronia ammophila starts to flower by the middle of June and 
continues producing flowers until a frost occurs that kills its 
aboveground parts, usually in late August or early September (NPS 
1999b, p. 6; Whipple 1999, p. 3; NPS 2000, unpaginated; Whipple 2002, 
p. 258). This extended blooming period is unusual in comparison to 
other plants in Yellowstone National Park (YNP) (Whipple 1999, p. 3). 
Additionally, unlike many of its associated species, A. ammophila 
continues to flower vigorously even after setting fruit (NPS 1999b, p. 
6; Whipple 2002, p. 258).
    Abronia ammophila is visited by several orders of insects (Saunders 
and Sipes 2004, p. 10; 2006, p. 80). The most frequent visitors to A. 
ammophila are lepidopterans (butterflies and moths) (Saunders and Sipes 
2004, p. 10; 2006, p. 80). Even though Abronia ammophila is visited by 
a diverse range of pollinators, the total number of pollinator 
visitations is extremely low (Saunders and Sipes 2006, p. 81). The low 
level of pollinator visits may be offset by A. ammophila exhibiting a 
mixed-mating system (Saunders and Sipes 2004, pp. 6, 10, 12; 2006, p. 
82). In addition to cross-pollination facilitated by pollinators, A. 
ammophila is able to self-pollinate with or without a pollen vector 
(Saunders and Sipes 2004, pp. 6, 10, 12; 2006, pp. 80-82; Whipple 
2010b, pers. comm.). Self-pollination is highly likely due to the 
floral morphology (the structure of the flower) and the functional 
phenology (life cycle) of A. ammophila (Saunders and Sipes 2006, p. 
81).
    Abronia ammophila is capable of producing large numbers of flowers 
(Saunders and Sipes 2004, p. 13). Seed dispersal mechanisms of Abronia 
ammophila have not been extensively studied. Primary seed dispersal 
appears to occur beneath the parent plant (Saunders and Sipes 2006, p. 
79). Seeds also accumulate in depressions of the sand, where the wind 
has blown them (NPS 1999b, p. 6; Whipple 2002, p. 258). The sticky 
surface of the seeds may facilitate dispersal, for example on the feet 
of waterfowl (NPS 1999b, pp. 6-7; Whipple 2002, p. 258). Water also may 
facilitate dispersal (Saunders and Sipes 2006, p. 79). As A. ammophila 
occurs in locations that are not located adjacent to each other, there 
appears to be an effective method of seed dispersal (NPS 1999b, pp. 6-
7; Whipple 2002, p. 258). However, the longevity of A. ammophila seeds 
in the seed bank in unknown (NPS 1999b, p. 7; Whipple 2002, p. 258).

Habitat

    Abronia ammophila is endemic to YNP, within Park and Teton Counties 
of Wyoming (Whipple 2002, p. 256; Fertig 2000b, unpaginated; Saunders 
and Sipes 2006, p. 76). Specifically, A. ammophila occurs around 
Yellowstone Lake typically within 40 m (131.2 ft) of the shoreline (NPS 
1999b, p. 5; Whipple 1999, p. 3; Fertig 2000b, unpaginated; Whipple 
2002, p. 262). The plant has been found up to 60 m (196.9 ft) inland 
and up to approximately 10 m (32.8 ft) above the high-water line (NPS 
1999b, p. 5; Whipple 1999, p. 3; Fertig 2000b, unpaginated; Whipple 
2002, p. 262). A. ammophila generally occurs above the high-water mark; 
no plants grow in areas that are regularly inundated (NPS 1999b, p. 5; 
Whipple 1999, p. 3; 2002, p. 262). Yellowstone Lake is a high-elevation 
(2,360 m (7,742 ft)), freshwater lake that was formed by volcanic 
activity (Pierce et al. 2007, pp. 131-132; NPS 2006a, unpaginated). The 
lake level was originally 61 m (200 ft) higher than its present level, 
and the level is not entirely stable (Pierce et al. 2007, pp. 131-132; 
NPS 2006a, unpaginated). A. ammophila appears to be able to adapt to 
the continually changing boundaries of its habitat as defined by 
Yellowstone Lake's fluctuations.
    Occurring between the area of beach affected by wave action and the 
more densely vegetated areas inland, Abronia ammophila prefers open, 
sunny, sparsely vegetated sites (NPS 1999b, p. 5; Whipple 2002, p. 262; 
Saunders and Sipes 2006, p. 77). Associated vegetative species include 
Phacelia hastata (silver-leaf scorpion-weed), Rumex venosus (veiny 
dock), Polemonium pulcherrimum (Jacob's-ladder), and Lupinus argenteus 
(silvery lupine) (NPS 1999b, p. 5; Whipple 2002, p. 262; Saunders and 
Sipes 2006, p. 77). A. ammophila loses its competitive advantage on 
more stable soils or in areas where Artemisia tridentata (big 
sagebrush) or Eriogonum umbellatum (sulfur flower buckwheat) occur 
(Whipple 2002, p. 262; Saunders and Sipes 2006, p. 77).
    Abronia ammophila occurs at four locations around Yellowstone Lake; 
these locations are identified as North

[[Page 33928]]

Shore, Rock Point, Pumice Point, and South Arm (NPS 1999a, pp. 3-6; NPS 
1999b, pp. 4-5; Whipple 2002, p. 262). These populations cover an area 
of 0.6 hectares (ha) (1.48 acres (ac)) (Whipple 2011, pers. comm.). The 
populations all occur in loose, unconsolidated (loosely arranged) sand 
with a minimal amount of fines (powdered material), gravel, or organic 
matter (NPS 1999b, p. 5; Whipple 2002, p. 262; Saunders and Sipes 2006, 
p. 77). All sites are located on beach sand except the Pumice Point 
site, which occurs on black sand (NPS 1999b, p. 5; Whipple 2002, p. 
262). Some of the populations occur in horseshoe-shaped, sandy 
depressions (blowouts) (NPS 1999a, p. 3; 1999b, p. 5; Whipple 2002, p. 
262; Saunders and Sipes 2006, p. 77). Additionally, the largest 
subpopulation in the North Shore area--the ``Thermal'' site--is located 
adjacent to a small thermal barren (area where no vegetation grows) 
(NPS 1999a, p. 6; NPS 1999b, p. 6). This area hosts an extremely dense 
population of Abronia ammophila with some of the largest individuals 
(NPS 1999b, p. 6). A. ammophila is able to coexist with thermal 
influences; however, most of the populations grow on ground that is not 
thermally influenced (NPS 1999a, p. 6).

Distribution and Abundance

    Herbarium records show that Abronia ammophila was previously more 
widely distributed along the northern shore of Yellowstone Lake (NPS 
1999b, p. 9; Whipple 2002, p. 258). Locations such as 0.40 kilometer 
(km) (0.25 mile (mi)) west of the mouth of Pelican Creek and several 
locations near the current Fishing Bridge development have been 
recorded as collection locations of A. ammophila (NPS 1999b, p. 9; 
Whipple 2002, pp. 258-259). Many additional areas of the northern 
shoreline provide suitable habitat for A. ammophila, such as west of 
Pelican Creek to the outlet of the Yellowstone River and Mary Bay (NPS 
1999b, p. 9; Whipple 2002, p. 259; Whipple 2010a, pers. comm.). 
Construction of the East Entrance Road and the Fishing Bridge 
campground, an area that was near the current parking area for the 
Fishing Bridge Museum, as well as higher human use may have extirpated 
populations of A. ammophila in these areas (NPS 1999b, pp. 8-9; Whipple 
2002, pp. 258-259; Whipple 2010a, pers. comm.).
    Table 1 below presents available information regarding the four 
populations of Abronia ammophila. The 1998-1999 survey was a rigorous 
population count (NPS 1999a, entire). The other years were generally 
estimates, except for some of the smaller populations where an exact 
count was easily obtained (Correy 2009, entire; Whipple 2010d, pers. 
comm.).

           Table 1--Population Estimates of Abronia ammophila
------------------------------------------------------------------------
     Population  (year of discovery)          Estimated numbers (year)
------------------------------------------------------------------------
North Shore (prior to 1998)..............  Approx. 1,000 (early 1990s).
                                           7,978 (1998-1999) rigorous
                                            count.
                                           Approx. 3,600 (2010).
Rock Point (1998)........................  325 (1998).
                                           120 (2009).
Pumice Point (1998)......................  22 (1998).
                                           1 (2001).
                                           5 (2009).
                                           24 (2010).
South Arm (1998).........................  1 (1998).
                                           3 (2005).
                                           2 (2010).
                                          ------------------------------
    Totals...............................  1,000 (early 1990s) (only
                                            North Shore known).
                                           8,326 (1998-1999) rigorous
                                            count.
                                           2,728 (2009) estimate.
                                           3,626 (2010) estimate.
------------------------------------------------------------------------
References: NPS 1999a, Appendix A; Corry 2009, Table 1; Whipple 2002, p.
  259; 2010d pers. comm.

    The majority of Abronia ammophila is found in the North Shore 
population scattered along a 2.41-km (1.5-mi) stretch of beach on the 
northern shoreline of Yellowstone Lake between the mouth of Pelican 
Creek and Storm Point (NPS 1999a, p. 3; 1999b, p. 4; Correy 2009, p. 
2). This population contains 95 percent or more of all A. ammophila 
(NPS 1999a, pp. 2, Appendix A; Whipple 2002, p. 264; Correy 2009, p. 
4). Prior to surveys conducted between 1995 and 1999, the North Shore 
population of A. ammophila was the only known population (NPS 1999a, p. 
3; Correy 2009, p. 2). Of the additionally discovered sites, two are 
located on the west shore of Yellowstone Lake: One at Rock Point, and 
one at a picnic area 1.6 km (1 mi) west of Pumice Point (NPS 1999a, p. 
5; NPS 1999b, p. 4). Additionally, a single plant was found during 
surveys on the east shore of the South Arm (NPS 1999a, p. 5). Not all 
suitable habitat within YNP has been surveyed (NPS 1999a, pp. 6-7).
    Casual surveys of the North Shore area in the early 1990s estimated 
the population to be around 1,000 plants (Correy 2009, pp. 1-2), with 
the majority of the plants of a large-size class representing mature, 
older plants (NPS 1999a, p. 1; 1999b, p. 7). No seedlings were observed 
(NPS 1999b, p. 7). Extensive surveys during the 1998-1999 field seasons 
conservatively estimated the North Shore population to consist of 7,978 
Abronia ammophila plants, with 45 percent of the population represented 
by young recruitment within the prior 2 years (recruit and medium class 
plants) (NPS 1999a, p. 1). The record high lake levels of 1996 and 1997 
appeared to improve the habitat conditions for A. ammophila by eroding 
the southern edge of the stabilized sand along the northern shoreline 
(NPS 1999b, p. 7; Whipple 2002, p. 265). Although this erosion washed 
away part of the existing habitat, it also improved conditions for 
recruitment of seedlings (NPS 1999b, p. 7; Whipple 2002, p. 265).
    During the 2009-2010 field season, surveys of the North Shore 
population yielded an approximate count of 3,600 A. ammophila plants 
(Correy 2009, p. 3; Whipple 2010d, pers. comm.; Whipple 2011, pers. 
comm.). The North Shore population can be split into four 
subpopulations (Correy 2009, p. 2). Two of these subpopulations had 
comparable population counts during both the 1998-1999 survey and the 
2009-2010 estimate (Correy 2009, pp. 3-4). The remaining two 
subpopulations, the Thermal and Long Skinny groups, had decreased in 
both total area populated and total number of plants (Correy 2009, p. 
5). The central portion of the Thermal group is now bare or mostly bare 
sand due to increased ground temperatures (due to changes within the 
Yellowstone geothermal basin), ground subsidence, increased scouring 
during storms, or a combination of such factors (Correy 2009, p. 5). 
The Long Skinny group also may have been affected by increased ground 
temperatures, particularly on the western end; furthermore, some of the 
habitat may have eroded (Correy 2009, p. 5). Additional factors 
potentially affecting the low population count include many years of 
drought (Whipple 2002, p. 265; Correy 2009, pp. 5-6) and lack of 
rigorous survey methods (Correy 2009, pp. 5-6).
    The Rock Point and Pumice Point Abronia ammophila populations were 
accurately counted in 1998 and 2009 (Correy 2009, Table 1). In 1998, 
the Rock Point population consisted of 324 individual plants; the 2009 
survey counted 120 individual plants (NPS 1999a, p. 6; Correy 2009, 
Table 1). An area of Rock Point surveyed in 1998 had no A. ammophila in 
June, but contained many medium-sized plants later in the summer (NPS 
1999a, p. 6). The Pumice Point population consisted of 22 plants in 
1998, whereas only 5 were counted in 2009 (NPS 1999a, p. 6; Correy 
2009,

[[Page 33929]]

Table 1). In 1998, the Pumice Point population contained a higher 
percentage of large (diameter greater than or equal to 5 up to 30 cm (2 
up to 11.8 in.)) and very large (diameter greater than or equal to 30 
cm (11.8 in.)) plants when compared to the North Shore population 
distribution (NPS 1999a, p. 6). Additionally, the Pumice Point 
population contained 24 plants in the 2010 field survey (Whipple 2010e, 
pers. comm.), which is comparable to the 1998 population count.
    The South Arm population contained only one large Abronia ammophila 
plant when it was discovered in 1998 (NPS 1999a, p. 6). When this site 
was revisited in 2005, the large individual found in 1998 was no longer 
present, but three small A. ammophila plants were present (Correy 2009, 
p. 2). Additionally, during the 2010 field survey, this population 
consisted of two plants (Whipple 2010e, pers. comm.).
    Dead and dying plants were counted during the 1998-1999 field 
surveys. Dead and dying Abronia ammophila plants accounted for 1.3 
percent of the total population (NPS 1999a, Appendix A). Of the dead A. 
ammophila plants, many were large individuals; however, some were 
failed seedlings (NPS 1999b, p. 7). The majority of dead and dying 
plants did not display obvious causes of mortality; they were 
interspersed throughout the communities (NPS 1999b, p. 7). 
Additionally, stressed A. ammophila plants are able to recover and put 
out new growth later in the season (NPS 1999b, p. 7).
    The Wyoming Natural Diversity Database (WNDD) has designated 
Abronia ammophila as a plant species of concern with ranks of G1 and S1 
(Heidel 2007, p. 1). This designation indicates that A. ammophila is 
considered to be critically imperiled because of extreme rarity (i.e., 
often less than five occurrences (a location where a plant or plants 
has been recorded)) or because some factor makes it highly vulnerable 
to extinction both at the global and State level; however, this ranking 
does not grant A. ammophila any special status under State legislation 
(WNDD 2009, unpaginated; WNDD 2010, unpaginated). Since A. ammophila is 
endemic to Wyoming, the Wyoming occurrences encompass the entire global 
range. Additionally, YNP considers A. ammophila to be a sensitive 
species of concern; therefore, it evaluates effects to this species in 
conjunction with any project or action that has the potential to affect 
the plant (Whipple 2011, pers. comm.).

Trends

    Natural fluctuations in the Abronia ammophila population from year 
to year or even within a season are not understood (Correy 2009, p. 6). 
From the first population estimates of the North Shore population in 
the early 1990s to the more rigorous survey conducted in 1998-1999, 
there was extensive recruitment and the A. ammophila population 
increased approximately 87 percent (NPS 1999a, p. 1; Correy 2009, pp. 
6, Table 1). Notably, 1996 and 1997 had high precipitation, with 
resultant high lake levels (NPS 1999a, p. 2). The 1998-1999 surveys 
recorded approximately 20 percent of the population to be seedlings or 
recruit size class (NPS 1999a, Appendix A). The 2009 population 
estimate of the North Shore populations shows a decrease from the 1998-
1999 survey (Correy 2009, Table 1). However, the 1998-1999 survey was 
an exact count, whereas the 2009 was an estimate. Additionally, the 
subsequent 2010 population estimate shows a slight increase in the 
population size compared to the 2009 population estimate (Whipple 
2010e, pers. comm.). Hypotheses for population fluctuations are 
changing thermal activity of the underlying area, ground subsidence, 
changing precipitation levels, and human and animal activity (Correy 
2009, pp. 5-6). The A. ammophila population seems to be stable within 
the parameters of a population that lives in an unstable habitat that 
fluctuates with wave action and weather (Whipple 2010a, pers. comm.).

Five Factor Evaluation for Abronia ammophila

    Information pertaining to Abronia ammophila in relation to the five 
factors provided in section 4(a)(1) of the Act is discussed below.

Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range

    Potential factors that may affect the habitat or range of Abronia 
ammophila are discussed in this section, including: (1) Development, 
(2) trampling, (3) nonnative invasive plants, (4) climate change, and 
(5) drought.
Development
    Abronia ammophila occurs entirely inside YNP, which limits 
potential threats to its habitat. By statute, regulation, and policy, 
YNP conserves wildlife and habitat; preserves and maintains biological 
processes, ecosystem components, and ecological integrity; controls 
invasive plants; and protects and monitors populations of sensitive 
plants and animals (See Yellowstone National Park under Factor D. The 
Inadequacy of Existing Regulatory Mechanisms in this Five Factor 
Evaluation for Abronia ammophila section). YNP was established prior to 
the States in which it is located (Mazzu 2010, pers. comm.; Whipple 
2010e, pers. comm.). This means that YNP owns not only the land, but 
also the mineral rights; therefore, energy development is not a threat 
(Mazzu 2010, pers. comm.; Whipple 2010e, pers. comm.). Construction of 
new roads, trails, or structures within YNP is rare, with 
reconstruction of existing features occurring occasionally. When new 
construction or reconstruction occurs in areas where there are 
sensitive species, YNP analyzes and carries out construction in a 
manner that minimizes adverse effects. A. ammophila populations are 
located a sufficient distance from roads; therefore, road 
reconstruction does not impact any of the A. ammophila populations 
(Whipple 2010e, pers. comm.).
    As noted above (see Distribution and Abundance), Abronia ammophila 
has been extirpated in some areas in which there is no longer habitat 
due to the construction of roads or structures. However, the 
construction in these areas occurred prior to YNP identifying A. 
ammophila as a species of conservation concern. Now, when new 
construction or reconstruction occurs, YNP analyzes and carries out 
construction in a manner that avoids adverse effects to sensitive 
species. Additionally, projects must be accompanied by a Resource 
Compliance Checklist that requires the evaluation of any potential 
impacts to resources including rare plants; if there are impacts, 
mitigation measures are developed (Schneider 2010, pers. comm.). The 
majority of YNP remains undeveloped, and we have no information that 
this will change; therefore, we do not consider development to be a 
threat to the species now or in the foreseeable future.
Trampling
    Trampling of Abronia ammophila, by both humans and wildlife, is a 
potential concern at most sites (Whipple 2010a, pers. comm.). The 
Abronia genus is vulnerable to disturbance by trampling (NPS 1999b, p. 
8; Whipple 2010e, pers. comm.). Trampling is frequently indicated as a 
threat to A. ammophila (e.g., NPS 1999a; 1999b); however, studies that 
seek to document trampling indicate that there is very little foot 
traffic actually impacting the populations of A. ammophila (NPS 1999a, 
pp. 2, 5).

[[Page 33930]]

    The North Shore population is located in one of the least visited 
portions of the north side of Yellowstone Lake's shoreline (NPS 1999b, 
p. 8). A large wetland restricts access to this site from the west (NPS 
1999b, p. 8). The Storm Point Trail approaches the east end of the 
North Shore population, and visitors occasionally walk down the beach 
toward this population (NPS 1999b, p. 8). The YNP plans to install a 
sign just past the Storm Point Trail requesting that visitors remain 
near the water and avoid sensitive vegetation areas (Schneider 2010, 
pers. comm.).
    The Pelican Creek Nature Trail is also near the North Shore 
population (Schneider 2010, pers. comm.). No plants currently occur in 
this area; however, it is historical habitat (Whipple 2010a, pers. 
comm.; Schneider 2010, pers. comm.). YNP is currently considering 
conservation measures, including closing all or part of this trail to 
protect the potential habitat (Whipple 2010a, pers. comm.; Schneider 
2010, pers. comm.). A final decision, on this trail, has not been made 
at this time (Whipple 2011, pers. comm.).
    The Pumice Point population of Abronia ammophila is located near an 
unmarked picnic area; the plants are located within 10 m (32.8 ft) of 
the picnic tables (NPS 1999b, p. 8). This area is currently unsigned 
(not marked as a picnic area from the main road), and the entrance is 
inconspicuous (Whipple 2010c, pers. comm.). Additionally, the A. 
ammophila in this area may be benefiting from the disturbance; if foot 
traffic did not occur, the area might be more densely vegetated and not 
available as habitat for A. ammophila (NPS 1999b, p. 8; Whipple 2010c, 
pers. comm.).
    The two remaining populations are in areas with little visitation 
(NPS 1999b, p. 8). The Rock Point population is approximately a half-
hour walk from the closest access point (Whipple 2010c, pers. comm.). 
The South Arm population is accessible by boat, with a backcountry 
campsite located about 200 m (656.2 ft) from the population (Whipple 
2010c, pers. comm.). This backcountry campsite has no trail access 
(Whipple 2010c, pers. comm.).
    YNP has received approximately 3 million visitors a year for the 
past 20 years; visitation was over 3 million for 11 of those years (NPS 
2010a, unpaginated). From January to September of 2010, YNP received 
3.4 million visitors, an increase of 8.7 percent over the previous year 
(NPS 2010b, unpaginated). Even with increases to visitation, we have no 
information indicating that the number of visitors correlates with 
increased trampling of Abronia ammophila populations to a level that 
poses a threat to the species.
    Wildlife trampling, particularly by ungulates, is occasionally 
indicated as a concern (Whipple 2010a, pers. comm.) We believe that 
these anecdotal observations do not add up to routine impacts on a 
scale that would cause the species to be threatened or endangered. 
Additionally, we believe that trampling by wildlife represents a 
natural ecological interaction in YNP that the species would have 
evolved with and poses no threat to long-term persistence.
    In summary, the populations of Abronia ammophila are located in 
areas of YNP that do not receive the bulk of visitor traffic. When 
surveys have attempted to document trampling by humans, observers had 
determined that the impact is minor. We have only anecdotal evidence of 
wildlife trampling. Therefore, we have no information indicating that 
trampling by either humans or wildlife is a threat to the species now 
or in the foreseeable future.
Nonnative Invasive Plants
    After habitat loss, the spread of nonnative invasive species is 
considered the second largest threat to imperiled plants in the United 
States (Wilcove et al. 1998, p. 608). Nonnative invasive plants alter 
ecosystem attributes including geomorphology, fire regime, hydrology, 
microclimate, nutrient cycling, and productivity (Dukes and Mooney 
2004, pp. 411-437). Nonnative invasive plants can detrimentally affect 
native plants through competitive exclusion, altered pollinator 
behaviors, niche displacement, hybridization, and changes in insect 
predation (D'Antonio and Vitousek 1992, pp. 74-75; DiTomaso 2000, p. 
257; Mooney and Cleland 2001, p. 5449; Levine et al. 2003, p. 776; 
Traveset and Richardson 2006, pp. 211-213).
    As of 2010, YNP has documented 218 nonnative plant species 
occurring within its boundaries (NPS 2010e, p. 1). Encroachment of 
invasive plants may potentially affect A. ammophila, as this species 
prefers open, sparsely vegetated sites and does not compete well in 
areas that are more densely vegetated.
    Currently, nonnative invasive plants have affected only a few sites 
occupied by Abronia ammophila (NPS 1999b, p. 8; Whipple 2010a, pers. 
comm.). The invasive grass Bromus tectorum (cheatgrass) has been noted 
in the vicinity of the North Shore population, and Cirsium arvense 
(Canada thistle) occurs near the Rock Point population (Whipple 2010a, 
pers. comm.). Additionally, some B. tectorum was documented around the 
Storm Point population (NPS 1999b, p. 8). To combat these occurrences, 
YNP has an exotic vegetation management plan in place that emphasizes 
prevention, education, early detection and eradication, control, and 
monitoring (Olliff et al. 2001, entire).
    In summary, nonnative invasive plants occur within YNP; however, 
the majority of these species do not impact the habitat of Abronia 
ammophila. A few nonnative invasive species have been documented near 
the habitat of A. ammophila. These species are being monitored and the 
National Park System (NPS) has mechanisms in place to help control 
these encroachments. We have no information indicating that nonnative 
invasive species are modifying the species habitat to the extent that 
it represents a threat to the species now or in the foreseeable future.
Climate Change
    The Intergovernmental Panel on Climate Change (IPCC) was 
established in 1988 by the World Meteorological Organization and the 
United Nations Environment Program in response to growing concerns 
about climate change and, in particular, the effects of global warming. 
The IPCC Fourth Assessment Report (IPCC 2007, entire) synthesized the 
projections of the Coupled Model Intercomparison Project (CMIP) Phase 
3, a coordinated large set of climate model runs performed at modeling 
centers worldwide using 22 global climate models (Ray et al. 2010, p. 
11). Based on these projections, the IPCC has concluded that the 
warming of the climate system is unequivocal, as evidenced from 
observations of increases in global average air and ocean temperatures, 
widespread melting of snow and ice, and rising global average sea level 
(IPCC 2007, pp. 6, 30; Karl et al. 2009, p. 17). Changes in the global 
climate system during the 21st century are likely to be larger than 
those observed during the 20th century (IPCC 2007, p. 19). Several 
scenarios are virtually certain or very likely to occur in the 21st 
century including: (1) Over most land, weather will be warmer, with 
fewer cold days and nights, and more frequent hot days and nights; (2) 
areas affected by drought will increase; and (3) the frequency of warm 
spells and heat waves over most land areas will likely increase (IPCC 
2007, pp. 13, 53).
    In some cases, climate change effects can be demonstrated and 
evaluated (e.g., McLaughlin et al. 2002, p. 6073). Where regional 
effects from global climate change have been demonstrated, we can

[[Page 33931]]

rely on that empirical evidence to predict future impacts, such as 
increased stream temperatures (see status review for Rio Grande 
cutthroat trout, 73 FR 27900; May 14, 2008) or loss of sea ice (see 
determination of threatened status for the polar bear, 73 FR 28212; May 
15, 2008), and treat these effects as a threat that can be analyzed. In 
instances for which a direct cause and effect relationship between 
global climate change and regional effects to a specific species has 
not been documented, we rely primarily on synthesis documents (e.g., 
IPCC 2007, entire; Independent Scientific Advisory Board 2007, entire; 
Karl et al. 2009, entire) to inform our evaluation of the extent that 
regional impacts due to climate change may affect our species. These 
synthesis documents present the consensus view of climate change 
experts from around the world. Additionally, we have examined models 
downscaled to specific regions (e.g., Ray et al. 2010, entire; WRCC 
2011, p. 1; CIG 2011, p. 1)--including some in-progress finer-scaled 
models that include Wyoming and the surrounding area--in order to 
inform our evaluation of the extent that regional impacts may threaten 
species. Typically, the projections of downscaled models agree with the 
projections of the global climate models (Ray et al. 2010, p. 25). 
Climate change projections are based on models with assumptions and are 
not absolute.
    Portions of the global climate change models can be used to predict 
changes at the regional-landscape scale; however, this approach 
contains higher levels of uncertainty than using global models to 
examine changes on a larger scale. The uncertainty arises due to 
various factors related to difficulty in applying data to a smaller 
scale, and to the paucity of information in these models such as 
regional weather patterns, local physiographic conditions, life stages 
of individual species, generation time of species, and species 
reactions to changing carbon dioxide levels. Additionally, global 
climate models do not incorporate a variety of plant-related factors 
that could be informative in determining how climate change could 
affect plant species (e.g., effect of elevated carbon dioxide on plant 
water-use efficiency, the physiological effect to the species of 
exceeding the assumed (modeled) bioclimatic limit, the life stage at 
which the limit affects the species (seedling versus adult), the life 
span of the species, and the movement of other organisms into the 
species' range) (Shafer et al. 2001, p. 207). Moreover, empirical 
studies are needed on what determines the distributions of species and 
species assemblages.
    Regional landscapes also can be examined by downscaling global 
climate models. Two common methods of downscaling are statistical 
downscaling and dynamic downscaling (Fowler et al. 2007, p. 1548). 
These downscaled models typically inherit the broad-scale results of 
global climate change models, imbed additional information, and run the 
models at a finer scale (Ray et al. 2010, p. 25, Hostetler 2011, pers. 
comm.). These methods provide additional information at a finer spatial 
scale (i.e., all of Wyoming downscaled to a 15-km (9.3-mi) resolution 
(Hostetler 2010, pers. comm.). However, they are not able to account 
for the myriad of processes that may affect a species that only 
inhabits a narrow range, as local effects may reduce or amplify the 
large-scale patterns that are projected over the larger spatial 
resolution of the global climate models (Ray et al. 2010, p. 24). In 
summary, global climate models can play an important role in 
characterizing the types of changes that may occur, so that the 
potential impacts on natural systems can be assessed (Shafer et al. 
2001, p. 213). However, they are of limited use to assess local impacts 
to species with a limited range, such as the five plants discussed in 
this finding.
    Climate change is likely to affect the habitat of Abronia 
ammophila, but we lack scientific information on what those changes may 
ultimately mean for the status of the species. Yellowstone Lake water 
levels affect habitat conditions for A. ammophila. As noted previously, 
the record high lake levels of 1996 and 1997 (due to increased snowpack 
and subsequent spring snowmelt) had both positive and negative effects 
on A. ammophila (NPS 1999b, p. 7; Whipple 2002, p. 265). In general, 
the outflow and maximum water surface elevation of Yellowstone Lake are 
functions of winter snow accumulation and spring precipitation inputs; 
these vary significantly from year to year (Farnes 2002, p. 73). 
Analysis of snow depth and last date of snow cover in YNP from 1948 to 
2003 has shown that winters are getting shorter, as measured by the 
number of days with snow on the ground (Wilmers and Getz 2005, entire). 
This change is due to decreased snowfall and an increase in the number 
of days with temperatures above freezing (Wilmers and Getz 2005, 
entire).
    Climate change effects are not limited to the timing and amount of 
precipitation; other factors potentially influenced by climate change 
may in turn affect the habitat conditions for Abronia ammophila. For 
example, fire frequency, insect populations (e.g., mountain pine 
beetle, Dendroctonus ponderosae), and forest pathogens may be 
influenced by climate change (Logan and Powell 2001, p. 170; Westerling 
et al. 2006, pp. 942-943) and may in turn affect forest canopy cover 
and the timing of snowmelt within the Yellowstone Lake watershed. The 
increased rate of snowmelt caused by fire-generated openings in the 
forest canopy from the 1988 fires in YNP may have slightly reduced the 
annual maximum Yellowstone Lake level because it spread the snowpack 
melt rate over a longer period of time (Farnes 2002, p. 73). Impacts of 
specific events on A. ammophila and its habitat have not been analyzed.
    Climate change is likely to affect multiple variables that may 
influence the availability of habitat for A. ammophila. As lake levels 
have fluctuated in the past and A. ammophila has adapted to these 
fluctuations, this species should be able to persist so long as climate 
change does not result in extreme changes to important characteristics 
of the species habitat, such as the complete loss of water from 
Yellowstone Lake. At this time, the best available scientific 
information does not indicate that impacts from climate change are 
likely to threaten the species now or in the foreseeable future.
Drought
    Precipitation studies show that YNP weather cycles typically follow 
the larger weather patterns across the larger Northern Rockies 
ecosystem (Gray et al. 2007, p. 24). The reconstruction of 
precipitation levels in YNP from AD 1173-1998 shows strong interannual 
variability (Gray et al. 2007, entire). Moreover, extreme wet and dry 
years, which have occurred recently, fall within the range of past 
variability (Gray et al. 2007, entire).
    We believe that Abronia ammophila has evolved to adapt to recurring 
drought conditions because it persists in this type of environment. 
Short-term population fluctuations appear to be typical for the 
species. The population at Rock Point was thought to have been 
extirpated due to drought; however, a survey in 2004 located seedlings 
at this site (Saunders and Sipes 2004, p. 4). The Pumice Point 
population completely vanishes some years. It is located on sand that 
does not connect to the aquifer, and during drought years the 
population can be 9.1 m (30 ft) above water (Whipple 2010e, pers. 
comm.). Although drought may temporarily influence the abundance of

[[Page 33932]]

plants at some specific locations, we have no information indicating 
that drought threatens the species now or in the foreseeable future.
Summary of Factor A
    YNP offers protection of Abronia ammophila populations from all 
kinds of development including roads, campgrounds, buildings, mining, 
and energy development. There are currently no plans for any further 
development in YNP near the existing populations or potential habitat 
of A. ammophila. We have no information to suggest that trampling, 
nonnative invasive plants, climate change, or drought represents a 
threat to the species.
    We conclude that the best scientific and commercial information 
available indicates that Abronia ammophila is not in danger of 
extinction or likely to become so within the foreseeable future because 
of the present or threatened destruction, modification, or curtailment 
of its habitat or range.

Factor B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    There has been limited use and collection of Abronia ammophila and 
its parts for scientific study (Saunders and Sipes 2006, p. 77). 
Additionally, the Denver Botanical Gardens (DBG) collected 
approximately 3,300 A. ammophila seeds in 2005 (DBG 2008, p. 3). The 
DBG is a participating institution in the Center for Plant 
Conservation, an organization dedicated to preventing the extinction of 
plants native to the United States (Center for Plant Conservation 2010, 
unpaginated). Because these collections were limited, we do not believe 
this collection constituted a threat to the species. The collections 
also contribute to the long-term conservation of the species.
    Specimens, seeds, and parts of Abronia ammophila are occasionally 
collected for scientific purposes in order to increase the knowledge of 
this species (e.g., Saunders and Sipes 2006; DBG 2008); however, these 
collections are rare. We do not have any evidence of risks to A. 
ammophila from overutilization for commercial, recreational, 
scientific, or educational purposes, and we have no reason to believe 
this factor will become a threat to the species in the future. We 
conclude that the best scientific and commercial information available 
indicates that A. ammophila is not in danger of extinction or likely to 
become so within the foreseeable future because of overutilization for 
commercial, recreational, scientific, or educational purposes.

Factor C. Disease or Predation

Disease
    Abronia ammophila is not known to be affected or threatened by any 
disease. Therefore, we do not consider disease to be a threat to A. 
ammophila now or in the foreseeable future.
Predation--Grazing and Herbivory
    No studies have been conducted investigating the effects of grazing 
or herbivory on Abronia ammophila. Minimal insect herbivory has been 
noted. Sphingid moth larvae and others tentatively identified in the 
family Noctuidae have been seen feeding on the aboveground plant parts 
(Saunders and Sipes 2004, p. 11). Also, what appeared to be an army 
cutworm caterpillar was observed eating the belowground parts of an 
uprooted plant (NPS 1999b, p. 7).
    Additionally, some uprooted, partially eaten taproots were found in 
areas with abundant rodent tunnels (NPS 1999b, p. 7). Ungulate grazing 
has been noted on species that grow near Abronia ammophila; however, 
none has been noted on A. ammophila (NPS 1999b, p. 7). Any predation, 
as noted above, would represent a natural ecological interaction in 
YNP. We have no evidence that the extent of such predation represents a 
population level threat to A. ammophila. Therefore, we do not consider 
predation to be a threat to the species now or in the foreseeable 
future.
Summary of Factor C
    We have no evidence of adverse impacts to Abronia ammophila from 
disease or predation. We conclude that the best scientific and 
commercial information available indicates that A. ammophila is not in 
danger of extinction or likely to become so within the foreseeable 
future because of disease or predation from herbivory or grazing.

Factor D. The Inadequacy of Existing Regulatory Mechanisms

    The Act requires us to examine the adequacy of existing regulatory 
mechanisms with respect to threats that may place Abronia ammophila in 
danger of extinction or likely to become so in the future. Existing 
regulatory mechanisms that could have an effect on potential threats to 
A. ammophila include (1) local land use laws, processes, and 
ordinances; (2) State laws and regulations; and (3) Federal laws and 
regulations. A. ammophila occurs entirely on Federal land under the 
jurisdiction of the YNP; therefore, the discussion below focuses on 
Federal laws. Actions adopted by local groups, States, or Federal 
entities that are discretionary, including conservation strategies and 
guidance, are not regulatory mechanisms; however, we may discuss them 
in relation to their effects on potential threats to the species.
Federal Laws and Regulations
Yellowstone National Park
    All known populations of Abronia ammophila occur within YNP. The 
YNP was established as the first national park on March 1, 1872, under 
control of the Secretary of the Department of the Interior (NPS 2010c, 
unpaginated). The NPS was established by the NPS Organic Act of 1916, 
and reaffirmed by the General Authorities Act, as amended (NPS 2008a, 
unpaginated; Schneider 2010, pers. comm.). The NPS Organic Act states, 
``[The NPS] shall promote and regulate the use of the Federal areas 
known as national parks, monuments, and reservations* * * to conserve 
the scenery and the natural and historic objects and the wild life 
therein and to provide for the enjoyment of the same in such manner and 
by such means as will leave them unimpaired for the enjoyment of future 
generations'' (16 USC 1) (NPS 2006b, p. 8; NPS 2008a, unpaginated; 
Schneider 2010, pers. comm.).
    Additionally, the Management Policies of the NPS state that 
conservation is paramount in situations of conflict between conserving 
resources and values and providing for enjoyment of them (NPS 2006b, p. 
9; Schneider 2010, pers. comm.). These policies also charge the NPS 
with preserving the fundamental physical and biological processes, and 
maintaining all the components and processes of a naturally evolving 
park ecosystem, including the natural abundance, diversity, and genetic 
and ecological integrity of the plant and animal species native to 
those ecosystems (NPS 2006b, pp. 35-36; Schneider 2010, pers. comm.). 
The NPS is responsible for the inventory of native species that are of 
special management concern to parks (such as rare, declining, 
sensitive, or unique species and their habitats) and will manage them 
to maintain their natural distribution and abundance (NPS 2006b, pp. 
45-46; Schneider 2010, pers. comm.). The Management Policies also 
direct the NPS to control detrimental nonnative species and manage 
detrimental visitor access (NPS 2006, p. 45).
    As stated above, YNP is required, to the maximum extent 
practicable, to

[[Page 33933]]

prevent exotic (nonnative invasive) plant introduction and to control 
established exotic plants by law, executive order, and management 
policy (e.g., Executive Order 13112, National Park Service Management 
Policies (NPS 1988), and the Federal Noxious Weed Act of 1974) (Olliff 
et al. 2001, pp. 348-349). YNP's approach emphasizes prevention, 
education, early detection and eradication, control, and monitoring 
(Olliff et al. 2001, entire).
    Visitors to national parks are prohibited from removing, defacing, 
or destroying any plant, animal, or mineral; this includes collecting 
natural or archeological objects (NPS 2006c, p. 2). Visitors are 
prohibited from driving off roadways or camping outside of designated 
campgrounds (NPS 2010d, unpaginated). Additionally, YNP has developed a 
Conservation Plan for Abronia ammophila (NPS 1999b, entire). This plan 
recommends the protection of all known (and any newly discovered) 
populations, monitoring of the populations, reestablishment of 
historical occupancy areas, long-term seed storage, and research (NPS 
1999b, pp. 10-11).
National Environmental Policy Act
    All Federal agencies are required to adhere to the National 
Environmental Policy Act (NEPA) of 1970 (42 U.S.C. 4321 et seq.) for 
projects they fund, authorize, or carry out. The Council on 
Environmental Quality's regulations for implementing NEPA (40 CFR 1500-
1518) state that agencies shall include a discussion on the 
environmental impacts of the various project alternatives, any adverse 
environmental effects which cannot be avoided, and any irreversible or 
irretrievable commitments of resources involved (40 CFR 1502). 
Additionally, activities on non-Federal lands are subject to NEPA if 
there is a Federal nexus. The NEPA is a disclosure law, and does not 
require subsequent minimization or mitigation measures by the Federal 
agency involved. Although Federal agencies may include conservation 
measures for sensitive species as a result of the NEPA process, any 
such measures are typically voluntary in nature and are not required by 
the statute.
Summary of Factor D
    We considered the adequacy of existing regulatory mechanisms to 
protect Abronia ammophila. We believe the existing regulatory 
mechanisms, especially the NPS Organic Act, adequately protect the 
Yellowstone Lake shore habitat of Abronia ammophila from the potential 
threats of development, trampling, and nonnative invasive plants. We 
expect that A. ammophila and its habitat will be generally protected 
from direct human disturbance. Therefore, we conclude that the existing 
regulatory mechanisms are adequate to protect A. ammophila from the 
known potential threat factors.
    We conclude that the best scientific and commercial information 
available indicates that Abronia ammophila is not in danger of 
extinction or likely to become so within the foreseeable future because 
of inadequate regulatory mechanisms.

Factor E. Other Natural or Manmade Factors Affecting Its Continued 
Existence

    Natural and manmade factors with the potential to affect Abronia 
ammophila include: (1) Small population size, (2) pollination, and (3) 
genetic diversity.
Small Population Size
    Small populations can be especially vulnerable to environmental 
disturbances such as habitat loss, nonnative species, grazing, and 
climate change (Barrett and Kohn 1991, p. 7; Oostermeijer 2003, p. 21; 
O'Grady 2004, pp. 513-514). However, plants that are historically rare 
may have certain adaptations to rarity (e.g., early blooming, extended 
flowering, or mixed-mating systems) that enable them to persist 
(Brigham 2003, p. 61).
    Based on herbarium records, extirpation of Abronia ammophila sites 
has occurred (see Distribution and Abundance discussion above). 
However, additional sites also have been recently discovered, and not 
all suitable habitat within YNP has been surveyed (NPS 1999a, pp. 6-7). 
We have no information on whether these new sites represent recent 
expansion of the species or if surveys were not previously conducted in 
these areas.
    We do not have any indication that Abronia ammophila was ever 
present on the landscape over a more extensive range. Existing sites 
are monitored, and surveys have located new occurrences. We have no 
information indicating that random demographic or environmental events 
are a threat to the species now or in the foreseeable future because of 
its small population size.
Pollination
    Small populations may represent an unreliable food source, which 
may be visited by fewer pollinators than larger, less fragmented 
populations (Oostermeijer 2003, p. 23). However, low visitation rates 
may be more of a concern in currently rare species that were 
historically abundant (Brigham 2003, p. 84). We have no information 
suggesting that Abronia ammophila was previously more abundant across 
the landscape. Co-flowering species (species that flower during the 
same timeframe) also may be important to pollination of A. ammophila; 
the pollinators recorded as visiting A. ammophila also were observed 
visiting other dune plants in the vicinity (Saunders and Sipes 2004, p. 
13).
    Only very limited information is available regarding pollination of 
Abronia ammophila. However, A. ammophila is a historically rare species 
that exhibits a mixed-mating system. A mixed-mating system and co-
flowering species may help alleviate negative effects that may occur 
due to low pollination visitation rates. Therefore, we have no 
information indicating that poor pollination is a threat to the species 
now or in the foreseeable future.
Genetic Diversity
    Small population size can decrease genetic diversity due to genetic 
drift (the random change in genetic variation each generation), and 
inbreeding (mating of related individuals) (Antonovics 1976, p. 238; 
Ellstram and Elam 1993, pp. 218-219). Genetic drift can decrease 
genetic variation within a population by favoring certain 
characteristics and, thereby, increasing differences between 
populations (Ellstram and Elam 1993, pp. 218-219). Self-fertilization 
and low dispersal rates can cause low genetic diversity due to 
inbreeding (Antonovics 1976, p. 238; Barrett and Kohn 1991, p. 21). 
This decreased genetic diversity diminishes a species' ability to adapt 
to the selective pressures of a changing environment (Newman and Pilson 
1997, p. 360; Ellstrand 1992, p. 77).
    Limited information is available regarding the genetic diversity of 
the Abronia genus. No information is available regarding the genetic 
diversity exhibited by Abronia ammophila. Therefore, we have no 
information indicating that a lack of genetic diversity is a threat to 
the species now or in the foreseeable future.
Summary of Factor E
    Abronia ammophila is a historically rare species that, as such, has 
adaptations such as a mixed-mating system and prolific flowering, which 
minimize the risks of small population size, low pollinator abundance, 
and genetic diversity. Therefore, we conclude that the best scientific 
and commercial information available indicates that Abronia ammophila 
is not in danger of extinction or likely to become so within the 
foreseeable future because of small population size,

[[Page 33934]]

pollination, or reduced genetic diversity.

Finding for Abronia ammophila

    As required by the Act, we considered the five factors in assessing 
whether Abronia ammophila is threatened or endangered throughout all of 
its range. We examined the best scientific and commercial information 
available regarding the past, present, and future threats faced by A. 
ammophila. We reviewed the petition, information available in our 
files, other available published and unpublished information, and we 
consulted with recognized A. ammophila experts and other Federal and 
State agencies.
    The primary factor potentially impacting Abronia ammophila is human 
disturbance through trampling. However, studies that have sought to 
quantify foot traffic in the habitat of A. ammophila have found that 
there is little foot traffic occurring (NPS 1999a, pp. 2, 5). 
Additionally, A. ammophila prefers open sites and thrives under some 
disturbance. Other factors potentially affecting A. ammophila--
including nonnative invasive plants, drought, small population size, 
limited pollinators, and genetic diversity--are either limited in 
scope, or lacking evidence apparent to us indicating that they 
adversely impact the species. We have no evidence that overutilization, 
disease, or predation are affecting this species. Although climate 
change will likely impact the status of some plant species in the 
future, we do not have enough information to determine that climate 
change will result in a species-level response from A. ammophila. 
Additionally, the existing regulatory mechanisms directing management 
of YNP appear to be adequate to protect the species from potential 
threats.
    Based on our review of the best available scientific and commercial 
information pertaining to the five factors, we find that the threats 
are not of sufficient imminence, intensity, or magnitude to indicate 
that Abronia ammophila is in danger of extinction (endangered) or 
likely to become endangered within the foreseeable future (threatened), 
throughout all of its range. Therefore, we find that listing A. 
ammophila as a threatened or endangered species is not warranted 
throughout its range.

Significant Portion of the Range

    Having determined that Abronia ammophila does not meet the 
definition of a threatened or endangered species, we must next consider 
whether there are any significant portions of the range where A. 
ammophila is in danger of extinction or is likely to become endangered 
in the foreseeable future.
    In determining whether Abronia ammophila is threatened or 
endangered in a significant portion of its range, we first addressed 
whether any portions of the range of A. ammophila warrant further 
consideration. We evaluated the current range of A. ammophila to 
determine if there is any apparent geographic concentration of the 
primary stressors potentially affecting the species including 
trampling, nonnative invasive plants, drought, small population size, 
limited pollinators, and genetic diversity. This species' small range 
suggests that stressors are likely to affect it in a uniform manner 
throughout its range. However, we found the stressors are not of 
sufficient imminence, intensity, magnitude, or geographically 
concentrated such that it warrants evaluating whether a portion of the 
range is significant under the Act. We do not find that A. ammophila is 
in danger of extinction now, nor is likely to become endangered within 
the foreseeable future, throughout all or a significant portion of its 
range. Therefore, listing A. ammophila as threatened or endangered 
under the Act is not warranted at this time.
    We request that you submit any new information concerning the 
status of, or threats to, Abronia ammophila to our Wyoming Ecological 
Services Field Office (see ADDRESSES section) whenever it becomes 
available. New information will help us monitor A. ammophila and 
encourage its conservation. If an emergency situation develops for A. 
ammophila, or any other species, we will act to provide immediate 
protection.

Species Information for Agrostis rossiae

Species Description

    Agrostis rossiae is a small annual grass in the family Poaceae 
(Clark et al. 1989, p. 8; Fertig 1994, unpaginated; 2000c, 
unpaginated). A. rossiae grows as a dense clump about 5 to 15 cm (2.0 
to 5.9 in.) high (Fertig 2000c, unpaginated). The short leaves are 1.0 
to 2.5 cm (0.39 to 0.98 in.) long, and 0.5 to 2.0 millimeters (mm) 
(0.02 to 0.08 in.) wide, with slightly inflated and smooth sheaths (the 
lower part of the leaf that surrounds the stem) (Clark et al. 1989, p. 
8; Clark and Dorn 1981, p. 10; Fertig 1994, unpaginated; 2000c, 
unpaginated). The one-flowered spikelets (flowers) form at the top of 
the stems in a narrow, compact panicle (a structure in which the 
flowers mature from the bottom upwards) that is 2.0 to 6.0 cm (0.79 to 
2.36 in.) long (Dorn 1980, p. 59; Fertig 2000c, unpaginated). The 
panicle remains compact at maturity (Fertig 1994, unpaginated). 
Branches of the panicle are scabrous (rough), purple, and lack 
spikelets at the base (Clark et al. 1989, p. 8; Dorn 1980, p. 59; 
Fertig 2000c, unpaginated).

Discovery and Taxonomy

    Edith A. Ross collected the first recorded specimen of Agrostis 
rossiae in July of 1890 (Vasey 1982, p. 77; Hitchcock 1905, p. 41). The 
genus Agrostis consists of over 100 species occurring in both 
hemispheres, typically in cooler areas of temperate climates (Hitchcock 
1905, p. 5). More recent sources list 150 to 200 species (Harvey 2007, 
unpaginated), or up to 220 species within the Agrostis genus (Watson 
and Dallwitz 1992, unpaginated).
    Species of the Agrostis genus are able to form morphologically 
similar ecotypes (subspecies that survives as a distinct group due to 
environmental pressures and isolation) in response to variations in 
climate, heavy metals in the soil, and other unusual soil conditions 
(Bradshaw 1959, entire; Jowett 1964, p. 78; Aston and Bradshaw 1966, 
entire; Jain and Bradshaw 1966, pp. 415-417). Therefore, morphology of 
Agrostis species is not a reliable indicator of species (Tercek 2003, 
p. 9).
    In the geothermally influenced areas of YNP, thermal Agrostis 
scabra (rough bentgrass) is sympatric (occurs in the same area) with 
Agrostis rossiae (Tercek 2003, pp. 9-10). A. scabra occurs as an annual 
in the thermal areas of YNP; however, this species is typically a 
perennial when it occurs in nonthermal habitats (Fertig 2000c, 
unpaginated; Tercek 2003, pp. 9-10). A. scabra can be distinguished 
from A. rossiae, when mature, by its spreading panicle (Fertig 1994, 
unpaginated; 2000c, unpaginated; Tercek 2003, pp. 9-10). Another 
similar species, although not sympatric, is Agrostis variabilis 
(mountain bentgrass), which is a perennial with panicle branches 
bearing spikelets nearly to the base (whereas A. rossiae lacks 
spikelets at the base) (Fertig 1994, unpaginated; Fertig 2000c, 
unpaginated). Genetic studies have shown that thermal Agrostis species 
occurring in YNP are more closely related to other thermal Agrostis 
species worldwide than to the nonthermal Agrostis scabra (Tercek 2003, 
pp. 17-21). Additionally, A. rossiae and thermal A. scabra are closely 
related to each other (Tercek et al. 2003, p. 1308-1309); however, 
additional genetic studies need to be completed to quantify their 
relationship. We recognize A. rossiae as a valid species and a listable 
entity.

[[Page 33935]]

Biology and Life History

    Agrostis rossiae is a thermal species that takes advantage of the 
warmth from its environment and germinates from December to January, 
when nonthermal areas remain covered in snow (Tercek 2003, pp. 12, 45, 
51). The growing season for A. rossiae is from December 1 to April 1; 
it blooms in May, matures in June, and dies by mid-June when the 
thermal ground temperature reaches between 40 and 45 [deg]C (104 and 
113 [deg]F) (a temperature that kills A. rossiae) (Beetle 1977, p. 40; 
Tercek 2003, pp. 10, 34, 12, 45, 51-52).
    Agrostis rossiae plants do not have a reduced seed set when 
isolated from external pollen sources; this suggests that A. rossiae 
reproduces through apomixis (reproduction that does not involve 
pollination) (Tercek 2003, p. 19). Seeds remain viable for about 100 
years in artificial conditions, but persist for less time in natural 
conditions (Tercek 2010, pers. comm.). Seeds do not disperse very far 
from the parent plant (Whipple 2010a, pers. comm.).

Habitat

    Typically, Agrostis rossiae grows on glacial deposits, which are at 
a slightly higher elevation than nearby hot springs (Tercek 2003, p. 
11). These deposits border active geysers and hot springs at elevations 
of 2,210 to 2,256 m (7,250 to 7,400 ft) (Clark et al. 1989, p. 8; 
Fertig 1994, unpaginated; 2000c, unpaginated). These geothermally 
influenced soils remain moist throughout the year even though they are 
partially isolated from the water table of nearby hot springs by the 
higher elevation or a nonpermeable rock layer (White et al. 1971, p. 
77; Fournier 1989, pp. 20-21; Tercek 2003, pp. 36, 45-46; Tercek and 
Whitbeck 2004, p. 1956).
    The geysers in YNP are vapor-dominated, meaning that steam and 
other gases rise out of the ground (Fournier 1989, pp. 20-21; Tercek 
2003, p. 36). The geysers are important to the soils because the 
elements and chemicals produced from the geysers affect the composition 
of the soil on which this species grows. The accompanying soils are 
rich in silica and calcium, and contain gases such as hydrogen sulfide 
and iron sulfide that are converted into sulfuric acid by bacteria 
(Tercek and Whitbeck 2004, p. 1956; White et al. 1971, p. 77; Fournier 
1989, pp. 20-21; Tercek 2003, p. 36). The sulfuric acid lowers the pH 
(a measure of acidity and alkalinity) of the soil (White et al. 1971, 
p. 77; Fournier 1989, pp. 20-21; Tercek 2003, p. 36). YNP's thermal 
soils are more acidic (pH 3.9-5.6), in general, than the nonthermal 
soils (pH 4.3-6.4) (Tercek and Whitbeck 2004, p. 1964). Agrostis 
rossiae demonstrates peak growth in acidic soils (pH 3.0), whereas the 
optimal growth of both thermal and nonthermal Agrostis scabra occurs at 
a pH of 5.0 (Terceck and Whitbeck 2004, p. 1964). While A. rossiae is 
more tolerant of acidity than other sympatric Agrostis species, its 
growth declines at pH of less than 3.0 (Tercek and Whitbeck 2004, p. 
1964). Many of the thermal features in YNP have a very high acidity 
(Whipple 2011, pers. comm.).
    In addition to Agrostis scabra, a limited number of thermally 
adapted species occur in the same habitat as Agrostis rossiae: 
Racomitrium canescens (Racomitrium moss), several heat-loving soil 
fungi, a heat-tolerant grass--Dichanthelium lanuginosum (panicgrass), 
and a few annual forbs (Tercek and Whitbeck 2004, p. 1956). Annual 
forbs include Conyza canadensis (Canadian horseweed), Gnaphalium 
stramineum (cottonbatting plant), Plantago elongata (Prairie plantain), 
Mimulus guttatus (seep monkeyflower), and Heterotheca depressa (hairy 
false goldenaster) (Fertig 2000c, unpaginated).

Distribution and Abundance

    Agrostis rossiae is endemic to YNP, occurring only in Teton County, 
Wyoming (Beetle 1977, p. 40; Clark and Dorn 1981, p. 10; Clark et al. 
1989, p. 8; Fertig 2000c, unpaginated, Tercek 2003, p. 10). Even though 
there are many thermal areas in YNP, Agrostis rossiae only occurs in 
the west-central portion of YNP (Tercek 2003, p. 10). Specifically, A. 
rossiae only occurs in the Firehole River drainage and the Shoshone 
Geyser Basin (Greater Yellowstone 2010, unpaginated). The reason for 
this restriction is not known. One proposed hypothesis is that the high 
acidity of some of the other thermal areas restricts the species' 
distribution; another is that A. rossiae is a fairly recently evolved 
species that has not had time for successive generations to disperse 
and colonize a wider area (Whipple 2010e, pers. comm.).
    Four known populations of the plant occur in an area of 
approximately 4.86 ha (12 ac); these populations are named Upper Geyser 
Basin, Shoshone, Midway, and Lower Geyser (Whipple 2010a, pers. comm.). 
Many of these occurrences are ephemeral (only persist for a short 
period) subpopulations (Fertig 2000c, unpaginated). Because of the 
changing thermal habitat, subpopulation numbers and locations may 
fluctuate greatly (Fertig 2000c, unpaginated). One small (generally 
less than 50 plants) subpopulation northeast of Infant Geyser in Geyser 
Hill disappeared due to changes in soil temperatures between 1992 and 
2008 (Fertig 2000c, unpaginated; Whipple 2010e, pers. comm.).
    The WNDD has designated Agrostis rossiae as a plant species of 
concern with ranks of G1 and S1 (Heidel 2007, p. 1). This designation 
indicates that A. rossiae is considered to be critically imperiled 
because of extreme rarity. For background information on G1 and S1 
rankings, please refer to the last paragraph under Distribution and 
Abundance in the Species Information for Abronia ammophila section. 
Since A. rossiae is endemic to Wyoming, the Wyoming occurrences 
encompass the entire global range. Additionally, YNP considers A. 
rossiae to be a sensitive species of concern; therefore, it evaluates 
effects to this species in conjunction with any project or action that 
has the potential to affect the plant (Whipple 2011, pers. comm.).

Trends

    Subpopulations can range in size from a solitary plant up to 
several thousand plants, in an area with a diameter of 100 m (328.1 ft) 
(Tercek 2003, p. 10; Tercek and Whitbeck 2004, p. 1956). Surveys 
conducted in 1995 suggest that the total population of all known 
Agrostis rossiae plants is approximately 5,000 to 7,500 individuals 
(Fertig 2000a, p. 36; 2000a, unpaginated). The 1998 survey determined 
the total population consisted of between 5,580 and 7,735 plants 
(Whipple in litt. 2009, entire). The entire population has not been 
surveyed in any additional years (Whipple in litt. 2009, entire). 
Surveys have been completed on a sporadic schedule, with not all 
populations surveyed in a given year (Whipple 2009 in litt., 
unpaginated). All population counts are estimates as A. rossiae is an 
annual with a clumped growth form, and exact counts are unable to be 
obtained without destroying the plants (Whipple 2010d, pers. comm.). 
Overall, there is not enough information to conclusively determine 
rangewide trends; however, the total population numbers appear to be 
stable despite subpopulation fluctuations. Additionally, the known 
populations have expanded in the last 3 years (Whipple 2010a, pers. 
comm.).

Five Factor Evaluation for Agrostis rossiae

    Information pertaining to Agrostis rossiae in relation to the five 
factors provided in section 4(a)(1) of the Act is discussed below.

[[Page 33936]]

Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range

    The following potential factors that may affect the habitat or 
range of Agrostis rossiae are discussed in this section, including: (1) 
Development, (2) trampling, (3) nonnative invasive species, (4) climate 
change, (5) thermal fluctuations, (6) drought, and (7) fire.
Development
    Agrostis rossiae occurs entirely inside YNP, which limits potential 
threats to its habitat from development. As stated above (see Factor D 
under Abronia ammophila), YNP owns both its land and the mineral rights 
so energy development within the YNP's boundary is not a threat (Mazzu 
2010, pers. comm.; Whipple 2010e, pers. comm.).
    In the late 1970s and early 1980s, potential for geothermal energy 
development outside YNP was considered a threat to Agrostis rossiae 
because of the potential to affect the thermal basin that underlies YNP 
(Fertig 2000, unpaginated). Currently, no known applications for 
geothermal leases have this potential (Mazzu 2010, pers. comm.; Whipple 
2010e, pers. comm.). However, applications are occasionally made for 
geothermal leases in the geothermal areas outside of YNP (NPS 2008b, 
unpaginated). The Geothermal Steam Act of 1970 (30 U.S.C. 1001-1027, 
December 24, 1970), as amended in 1977, 1988, and 1993, provides 
protections for the thermal features in YNP (see Factor D. The 
Inadequacy of Existing Regulatory Mechanisms below) (Legal Information 
Institute 2010, unpaginated). This law should protect the species, 
unless high energy costs, such as occurred in the late 1970s and early 
1980s, encourage development interest that results in changes that 
weaken these protections. Therefore, A. rossiae is not threatened by 
geothermal energy development inside or outside of YNP's boundary.
    As stated above, new construction of roads, trails, or structures 
occurring in YNP is rare, with reconstruction of existing features 
occurring occasionally (Whipple 2010e, pers. comm.). When new 
construction or reconstruction occurs in areas where there are 
sensitive species, YNP analyzes and carries out construction in a 
manner that minimizes adverse effects. For example, the reconstruction 
of the Biscuit Basin Boardwalk in the summer of 2010 included rerouting 
the boardwalk and restoration of Agrostis rossiae habitat that had been 
impacted during prior maintenance (Whipple 2010a, pers. comm.; 2010e, 
pers. comm.).
    The majority of YNP remains undeveloped, and we have no information 
that this will change; therefore, we do not view development to be a 
threat to the species now or in the foreseeable future.
Trampling
    Most habitat of Agrostis rossiae is easily accessible to visitors, 
as it is generally located near popular thermal features in YNP 
(Whipple 2010a, pers. comm.). However, visitors are required to stay on 
boardwalks and designated trails around thermal areas (NPS 2006c, 
unpaginated). Human impact to A. rossiae was noted in a survey of the 
Shoshone Geyser Basin area (Whipple 2009 in litt., unpaginated). This 
trampling was partially mitigated by the reroute discussed above; 
surveys in 2000, after the trail was rerouted, documented a healthy A. 
rossiae population (Whipple 2009 in litt., unpaginated). No studies 
have specifically examined disturbance due to trampling or its effects 
on A. rossiae. However, A. rossiae is typically located in the vicinity 
of thermal features that could be detrimental for humans to walk near, 
and any areas that have the potential for trampling are protected by 
YNP's policies.
    For information on impacts of increased visitation to YNP, please 
refer to the ``Trampling'' discussion under Factor A. The Present or 
Threatened Destruction, Modification, or Curtailment of Its Habitat or 
Range in the Five Factor Evaluation for Abronia ammophila section. As 
the plant is located in YNP, it is afforded protections (see Factor D: 
The Inadequacy of Existing Regulatory Mechanisms below).
    Wildlife, also, have the potential to trample Agrostis rossiae. 
American bison (Bison bison) scat (fecal droppings) has been found in 
the vicinity of A. rossiae at several sites; however, no trampling of 
A. rossiae was noted in the survey notes (Whipple 2009 in litt., 
unpaginated). In 1998, a small patch of A. rossiae was highly impacted 
by the actions of a rutting bull elk (Cervus canadensis); however, that 
A. rossiae population was reported to be healthy when resurveyed in 
2000 (Whipple 2009 in litt., unpaginated). We believe that these 
anecdotal observations do not add up to routine impacts on a scale that 
would cause the species to be threatened or endangered. Additionally, 
we believe that trampling by wildlife, as noted above, represents a 
natural ecological interaction in YNP with which the species would have 
evolved and poses no threat to long-term persistence.
    We have no information indicating that trampling by either humans 
or wildlife is a threat to the species now or in the foreseeable 
future.
Nonnative Invasive Plants
    For general background information on nonnative invasive plants, 
please refer to the first paragraph of ``Nonnative Invasive Plants'' 
under Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range in the Five Factor Evaluation for 
Abronia ammophila section.
    As stated above, as of 2010, YNP has documented 218 nonnative plant 
species occurring within its boundaries (NPS 2010e, p. 1). The majority 
of these plants have not been documented in or around Agrostis rossiae 
habitat. Encroachment of nonnative species has the potential to affect 
Agrostis rossiae. However, at this time, none of the nonnative species 
are able to tolerate the hottest of the thermal habitats, where A. 
rossiae primarily grows (Whipple 2010e, pers. comm.). Several nonnative 
species that are considered either invasive or exotic occur near the 
thermal habitats of A. rossiae (Whipple 2009 in litt., entire). In 
order to combat nonnative invasives that can tolerate the transition 
areas closer to the thermal habitat of A. rossiae, YNP is targeting 
Rumex acetosella (common sheep sorrel) around the Shoshone Geyser Basin 
(Schneider 2010 pers. comm.) and Hypericum perforatum (St. John's wort) 
near the Lower Geyser Basin (Whipple 2010f, pers. comm.). Additionally, 
NPS plans to establish trial plots in some of the geyser basins to 
determine the best control mechanisms (Schneider 2010 pers. comm.). 
Nonnative species currently occur only within the transition zones and 
not in the hot thermal habitat of A. rossiae. Additionally, the NPS has 
an exotic plant management plan (see Factor D: The Inadequacy of 
Existing Regulatory Mechanisms in the Five Factor Evaluation for 
Abronia ammophila section), which includes measures to identify and 
treat any new nonnatives; therefore, we believe that A. rossiae will be 
protected from nonnative plant invasions.
    We have no information indicating that nonnative invasive species 
are modifying the habitat of Agrostis rossiae to the extent that they 
represent a threat to the species now or in the foreseeable future.

[[Page 33937]]

Climate Change
    For general background information on climate change, please refer 
to the first paragraphs of ``Climate Change'' under Factor A. The 
Present or Threatened Destruction, Modification, or Curtailment of Its 
Habitat or Range in the Five Factor Evaluation for Abronia ammophila 
section.
    Agrostis rossiae is adapted to an ephemeral habitat subject to 
lethal summer soil temperatures and appears most clearly influenced by 
the condition of thermal features as opposed to other climatic factors. 
Although climate change has the potential to affect the species' 
habitat, it is not clear that climate change has relevance to the 
condition or availability of habitat for this species because we have 
no information that climate change will play a significant role in 
altering geothermal features. Climate change may affect the timing and 
amount of precipitation as well as other factors linked to habitat 
conditions for this species. We are uncertain how these changes will 
affect the geothermal habitat of A. rossiae. At this time the available 
scientific information does not clearly indicate that climate change is 
likely to threaten the species now or in the foreseeable future.
Thermal Fluctuations
    The thermal features in YNP are part of the largest and most varied 
geyser basin in the world; this basin is essentially undisturbed (NPS 
2008b, unpaginated). Few of YNP's thermal features have ever been 
diverted for human use (such as bathing pools or energy), despite the 
proximity of roads and trails (NPS 2008b, unpaginated). Thermal 
features can be affected by nearby ground-disturbing activities; water, 
sewer, and other utility systems adjacent to YNP have likely affected 
the park's features in the past (NPS 2008b, unpaginated). In other 
countries, geothermal drill holes and wells located 4.02 to 9.98 km 
(2.5 to 6.2 mi) from thermal features have reduced geyser activity and 
hot spring discharges (NPS 2008b, unpaginated). Connections between 
YNP's underlying geothermal basins are not fully understood. Therefore, 
if geothermal activities were to occur outside YNP, they could have the 
potential to affect this species.
    Agrostis rossiae tends to follow very subtle geothermal features, 
growing along geothermal cracks and edges of sunken pools (Whipple 
2010e, pers. comm.). For example, in Cathos Springs, A. rossiae 
currently grows along one crack and in a ring around the spring; 
however, when the water level is higher or the ground level hotter, the 
distribution shifts, or the plant may not be present at all in a given 
year (Whipple 2010e, pers. comm.). As discussed above, the Geothermal 
Steam Act of 1970 (30 U.S.C. 1001-1027, December 24, 1970), as amended 
in 1977, 1988, and 1993, prevents significant adverse effects to the 
thermal features in YNP (see Factor D: The Inadequacy of Existing 
Regulatory Mechanisms below) (Legal Information Institute 2010, 
unpaginated). Additionally, the NPS is included in discussions of 
activities that may affect the groundwater or geothermal areas of YNP 
(Mazzu 2010, unpaginated). Therefore, we have no information indicating 
that human-caused changes to the thermal features are likely to 
threaten the species now or in the foreseeable future.
Drought
    For background information, please refer to the first paragraph of 
the ``Drought'' discussion under Factor A. The Present or Threatened 
Destruction, Modification, or Curtailment of Its Habitat or Range in 
the Five Factor Evaluation for Abronia ammophila section. As noted 
above under the Habitat section for this species, the vapor-dominated 
geothermally influenced soils on which Agrostis rossiae typically grows 
remain moist throughout the year (Tercek 2003, pp. 36, 45-46). However, 
these soils are influenced by the amount and timing of the rain that 
falls in the area (Tercek and Whitbeck 2004, p. 1958). Typically around 
May or June, the snow in the surrounding area has melted and rains are 
no longer frequent enough for the soils in the areas surrounding the 
habitat of A. rossiae to remain moist (Tercek and Whitbeck 2004, p. 
1958). This decrease in soil moisture of the surrounding habitat is 
accompanied by a sharp increase in the thermal soil temperatures 
(Tercek and Whitbeck 2004, p. 1958). The typical growing season in the 
hot thermal habitats is approximately 120 days (Tercek and Whitbeck 
2004, p. 1963). A. rossiae requires only 30 to 70 days to complete its 
life cycle (Tercek and Whitbeck 2004, p. 1963). A decrease in the 
growing season of 40 percent could occur prior to drought having a 
detrimental effect on this species. Prediction models indicate that 
areas already affected by drought will suffer greater effects from 
temperature increases caused by climate change and that high 
precipitation effects will become more frequent (IPCC 2007, entire). 
Although we do not fully understand how these changes will affect the 
habitat of A. rossiae, we do know that this species is resilient to 
changes in the thermal basins of its environment. Therefore, we do not 
believe that drought will rise to the level of a threat to the species 
now or in the foreseeable future.
Fire
    As Agrostis rossiae completes its annual life cycle by mid-June, it 
is typically dead by the time fire season occurs (Whipple 2010e, pers. 
comm.); YNP's fire season generally extends from late June to the first 
large rain events in September. The fires in 1988 burned the area where 
A. rossiae occurs; however, the fire did not carry on the ground 
through the A. rossiae populations and, therefore, did not have any 
effect on the population (Whipple 2010e, pers. comm.). We have no 
information indicating that fire is likely to threaten the species now 
or in the foreseeable future.
Summary of Factor A
    YNP offers protection to the populations of Agrostis rossiae from 
all kinds of development, including roads, campgrounds, buildings, 
mining, and energy development. There are currently no plans for any 
further development in YNP near the existing populations or potential 
habitat of A. rossiae. We have no information to show that Agrostis 
rossiae is likely to be threatened by trampling, nonnative species, 
climate change, thermal fluctuations, drought, or fire.
    We conclude that the best scientific and commercial information 
available indicates that Agrostis rossiae is not in danger of 
extinction or likely to become so within the foreseeable future because 
of the present or threatened destruction, modification, or curtailment 
of its habitat or range.

Factor B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    There has been limited use and collection of the leaves of Agrostis 
rossiae for scientific purposes to determine the genetic relationship 
between different Agrostis species (Tercek 2003, p. 12). We have no 
indications of A. rossiae being collected for any other purposes 
(Whipple 2010e, pers. comm.). Therefore, we conclude that the best 
scientific and commercial information available indicates that A. 
rossiae is not in danger of extinction or likely to become so within 
the foreseeable future because of overutilization for commercial, 
recreational, scientific, or educational purposes.

[[Page 33938]]

Factor C. Disease or Predation

    Agrostis rossiae is not known to be affected or threatened by any 
disease. We have no records showing predation by grazing or herbivory 
on A. rossiae. Therefore, we conclude that the best scientific and 
commercial information available indicates that A. rossiae is not in 
danger of extinction or likely to become so within the foreseeable 
future because of disease or predation.

Factor D. The Inadequacy of Existing Regulatory Mechanisms

    All known populations of Agrostis rossiae occur within YNP, which 
is under the jurisdiction of the NPS. Please refer to Yellowstone 
National Park under the Factor D: The Inadequacy of Existing Regulatory 
Mechanisms section in the Five Factor Evaluation for Abronia ammophila 
section for additional information.
    The Geothermal Steam Act of 1970 (30 U.S.C. 1001-1027, December 24, 
1970), as amended in 1977, 1988, and 1993, governs the lease of 
geothermal resources on public lands (Legal Information Institute 2010, 
unpaginated). In addition to preventing the issuance of geothermal 
leases on lands in YNP, it prevents the issuance of any lease that is 
reasonably likely to result in a significant adverse effect on thermal 
features within YNP (Legal Information Institute 2010, unpaginated).
Summary of Factor D
    The existing regulatory mechanisms, especially the NPS Organic Act 
and the Geothermal Steam Act, appear to adequately protect Agrostis 
rossiae and its habitat in YNP. We expect that A. rossiae and its 
habitat will be generally protected from direct human disturbance. 
Therefore, we conclude that the existing regulatory mechanisms are 
adequate to protect A. rossiae from the known potential threat factors.
    We conclude that the best scientific and commercial information 
available indicates that Agrostis rossiae is not in danger of 
extinction or likely to become so within the foreseeable future because 
of the inadequacy of existing regulatory mechanisms, provided the 
existing mechanisms are not weakened or removed.

Factor E. Other Natural or Manmade Factors Affecting Its Continued 
Existence

    Natural and manmade factors with the potential to affect Agrostis 
rossiae include: (1) Competition and hybridization, (2) small 
population size, and (3) genetic diversity.
Competition and Hybridization
    Previously, Agrostis scabra has been listed as a threat to Agrostis 
rossiae, possibly because of competition or hybridization (e.g., Fertig 
2000a; 2000c; NatureServe 2010a, p. 1). However, A. scabra is a native 
species that does not compete with or restrict A. rossiae (Whipple 
2010a, pers. comm.). The thermal areas in which A. rossiae grows have 
lethal summer soil temperatures (greater than 45 [deg]C (113 [deg]F)) 
that preclude the growth of perennial roots and reproduction of any 
plant that requires greater than 120 days to complete its life cycle 
(Tercek 2003, p. 51). Nonthermal A. scabra is able to germinate in 
garden experiments of thermal temperatures; however, nonthermal A. 
scabra seldom occurs in the interior of the thermal habitats where A. 
rossiae occurs (Tercek 2003, p. 53). Additionally, nonthermal A. scabra 
requires a growing season of approximately 160 days in order to flower; 
the typical growing season in the transition zone between thermal and 
nonthermal ground is approximately 105 days (Tercek 2003, p. 52). 
Therefore, even if the nonthermal A. scabra germinated in the 
transition zone, it would be unable to reproduce before desiccation 
occurred.
    Conversely, thermal Agrostis scabra is able to flower at the same 
time as Agrostis rossiae (Tercek 2003, p. 10). However, each thermal 
area is typically populated by only one of these species because of 
differences in microhabitat requirements (e.g., soil temperature, soil 
pH) (Tercek 2003, p. 10). A few thermal areas do support populations of 
both A. rossiae and thermal A. scabra (Whipple 2010e, pers. comm.); 
however, A. rossiae and thermal A. scabra maintain separate 
morphologies in these locations and when they are grown under uniform 
laboratory conditions (Tercek et al. 2003, p. 1311; Whipple 2010e, 
pers. comm.). Additionally, attempts to cross-pollinate A. rossiae and 
thermal A. scabra were unsuccessful; however, experiments that are more 
rigorous are needed to determine conclusively whether these two 
Agrostis species can hybridize (Tercek 2003, p. 19) and to confirm that 
there is not a crossbreeding effect that could be a threat to A. 
rossiae.
Small Population Size
    For general background information on small population size, please 
refer to the first paragraph of ``Small Population Size'' under Factor 
E. Other Natural or Manmade Factors Affecting Its Continued Existence 
in the Five Factor Evaluation for Abronia ammophila section.
    We do not have any indication that Agrostis rossiae was ever 
present on the landscape over a more extensive range. Nor do we have 
any evidence that the populations of A. rossiae are sufficiently small 
to experience the problems that occur in some species because of small 
population size. Additionally, A. rossiae has the potential to expand 
its habitat, although potential habitat may be limited (see 
Distribution and Abundance) (Whipple 2010e, pers. comm.). We have no 
information indicating that random demographic or environmental events 
are a threat to the species because of a small population size. 
Therefore, we do not consider small population size to be a threat to 
A. rossiae now or in the foreseeable future.
Genetic Diversity
    For general background information on genetic diversity, please 
refer to the first paragraph of ``Genetic Diversity'' under Factor E. 
Other Natural or Manmade Factors Affecting Its Continued Existence in 
the Five Factor Evaluation for Abronia ammophila section.
    Decreased genetic diversity diminishes a species' ability to adapt 
to the selective pressures of a changing environment (Newman and Pilson 
1997, p. 360; Ellstrand 1992, p. 77). However, Agrostis rossiae 
continually adapts to the changing thermal conditions of its 
environment and is able to shift its distribution to follow these 
changes (Whipple 2010e, pers. comm.). Therefore, potential decreased 
genetic diversity does not appear to be affecting A. rossiae.
    Gene flow can also have negative effects on a species (Ellstrand 
1992, p. 77). Genes favoring adaptations to a different environment or 
hybridization between two species can result (Ellstrand 1992, p. 77). 
Gene flow between Agrostis populations is low (Tercek 2003, p. 19). 
Therefore, there may be some risk to the species, but we do not fully 
understand this risk based on currently available information.
    Limited information is available about the genetic diversity of 
Agrostis rossiae. We do not have any indication that A. rossiae is at 
risk of suffering from reduced genetic diversity and consider it 
capable of adapting to changes based on our current understanding of 
the species' genetics. Therefore, we do not consider reduced genetic 
diversity to be a threat to A. rossiae now or in the foreseeable 
future.

[[Page 33939]]

Summary of Factor E
    Agrostis scabra is a native species that does not outcompete or 
invade the habitat of Agrostis rossiae. Typically, these two species do 
not occur together. Additionally, we have no information to suggest 
that small population size or reduced genetic diversity limit A. 
rossiae. We conclude that the best scientific and commercial 
information available indicates that Agrostis rossiae is not in danger 
of extinction or likely to become so within the foreseeable future 
because of competition or hybridization, small population size, or 
reduced genetic diversity.

Finding for Agrostis rossiae

    As required by the Act, we considered the five factors in assessing 
whether Agrostis rossiae is threatened or endangered throughout all of 
its range. We examined the best scientific and commercial information 
available regarding the past, present, and future threats faced by A. 
rossiae. We reviewed the petition, information available in our files, 
and other available published and unpublished information, and we 
consulted with recognized A. rossiae experts and other Federal and 
State agencies.
    The primary factors potentially impacting Agrostis rossiae are 
visitor impacts, the invasion of Agrostis scabra, and changing thermal 
activity. However, A. scabra is a native species that typically does 
not compete with A. rossiae, the existing boardwalks and trails offer 
sufficient pathways for visitors to navigate around the thermal areas, 
and sufficient regulatory mechanisms exist to prevent human-caused 
changes to the thermal basin by groundwater or geothermal development. 
Other factors affecting A. rossiae--including nonnative invasive 
plants, drought, small population size, and genetic diversity--are 
either limited in scope, or lacking evidence apparent to us indicating 
that they adversely impact the species as a whole. We have no evidence 
that overutilization, disease, or predation are affecting this species. 
Although climate change may impact the species in the future, we do not 
have enough information to determine that climate change will elicit a 
species-level response from A. rossiae. Based on our knowledge of the 
species, the regulatory mechanisms to protect the species appear 
appropriate.
    Based on our review of the best available scientific and commercial 
information pertaining to the five factors, we find that the threats 
are not of sufficient imminence, intensity, or magnitude to indicate 
that Agrostis rossiae is in danger of extinction (endangered), or 
likely to become endangered within the foreseeable future (threatened), 
throughout all of its range. Therefore, we find that listing A. rossiae 
as a threatened or endangered species is not warranted throughout all 
of its range.

Significant Portion of the Range

    Having determined that Agrostis rossiae does not meet the 
definition of a threatened or endangered species, we must next consider 
whether there are any significant portions of the range where A. 
rossiae is in danger of extinction or is likely to become endangered in 
the foreseeable future.
    In determining whether Agrostis rossiae is threatened or endangered 
in a significant portion of its range, we first addressed whether any 
portions of the range of A. rossiae warrant further consideration. We 
evaluated the current range of A. rossiae to determine if there is any 
apparent geographic concentration of the primary stressors potentially 
affecting the species including visitor-related impacts (trampling), 
changing thermal activity, nonnative invasive plants, drought, small 
population size, and genetic diversity. This species' small range 
suggests that stressors are likely to affect it in a uniform manner 
throughout its range. Furthermore, we found the stressors are not of 
sufficient imminence, intensity, magnitude, or geographically 
concentrated such that it warrants evaluating whether a portion of the 
range is significant under the Act. We do not find that A. rossiae is 
in danger of extinction now, nor is it likely to become endangered 
within the foreseeable future throughout all or a significant portion 
of its range. Therefore, listing A. rossiae as threatened or endangered 
under the Act is not warranted at this time.
    We request that you submit any new information concerning the 
status of, or threats to, Agrostis rossiae to our Wyoming Ecological 
Services Field Office (see ADDRESSES section) whenever it becomes 
available. New information will help us monitor A. rossiae and 
encourage its conservation. If an emergency situation develops for A. 
rossiae, or any other species, we will act to provide immediate 
protection.

Species Information for Astragalus proimanthus

Species Description

    Astragalus proimanthus is a mat-forming, stemless, perennial herb 
measuring 2 to 3 dm (7.9 to 11.8 in.) in diameter (Fertig 2001, 
unpaginated) and up to 4 cm (1.6 in.) in height (Dorn 1979 in litt., 
unpaginated). The densely clustered, 1.0- to 3.5-cm-long (0.39- to 
1.38-in.-long) leaves are divided into three narrow, 5- to 9-mm-long 
(0.2- to 0.4-in.-long) leaflets (small leaflike divisions of a larger 
compound leaf) (Fertig and Welp 2001, p. 7). The plants are covered 
with fine hairs and appear silvery, with leaflets that are equally 
hairy on both sides (Barneby 1964, p. 1153). The 17-mm-long (0.67-in.-
long), asymmetrical, pea-like flowers have five petals: one large broad 
upper petal, two side petals, and two lower petals that form a canoe 
shape (Fertig and Welp 2001, p. 7). The broad upper petal, called the 
banner petal, is constricted along the midline, forming a fiddle shape 
(Roberts 1977, p. 63). The yellow to whitish flowers are often tinged 
with lavender or pink, especially near the center, and occur in pairs 
at the base of the leaves (Fertig and Welp 2001, p. 7). This plant has 
a taproot that is woody and branching (Barneby 1964, p. 1153).

Discovery and Taxonomy

    The first specimens of Astragalus proimanthus were discovered and 
collected 9.7 km (6 mi) north of the town of McKinnon (Sweetwater 
County, Wyoming) on June 13, 1946, by H.C. Ripely and R.C. Barneby 
(Barneby 1964, p. 1154). A second population was located in 1961 
(Barneby 1964, p. 1154). The population discovered in 1961 was 
collected from and revisited multiple times in the decades that 
followed; however, the population discovered in 1946 could not be 
relocated after multiple attempts (Fertig and Welp 2001, p. 8). In 
2000, two populations were discovered, one of which may be the original 
site collected by Barneby in 1946 as this population was found 9.7 km 
(6 mi) north of the town of McKinnon (Fertig and Welp 2001, p. 9).
    The flowering plant genus Astragalus is the largest genus of 
vascular plants (Montana Plant Life 2010, unpaginated). With the common 
names ``milk-vetch'' or ``locoweed'' (family Fabaceae or Leguminosae), 
the genus contains more than 2,000 species, which are distributed 
worldwide, although they are primarily found in the northern hemisphere 
(Barneby 1989, p. 1; Montana Plant Life 2010, unpaginated). Based on 
similar morphological features of the flower, calyx (collective term 
for the sepals, which are the green, leaflike structures that protect 
the delicate inner parts of the flower while it is developing), and 
fruits, Astragalus proimanthus is in a taxonomic grouping within 
Oropahca (subgenus) with Astragalus gilviflorus (Dubois milkvetch) and 
Astragalus hyalinus

[[Page 33940]]

(summer milkvetch), which both occur in Wyoming (Fertig and Welp 2001, 
p. 6). A. proimanthus has been considered a descendant of A. hyalinus 
(Roberts 1977, p. 63). A. proimanthus is similar to A. hyalinus in its 
dwarf habit of growth and short flower with fiddle-shaped banner petal, 
but it is dissimilar in having smooth, hairless petals and an earlier 
flowering period (by a month or so) (Barneby 1964, p. 1154). 
Additionally, A. proimanthus grows in a small, compact form and not in 
a large, highly curved cushion characteristic of A. hyalinus. A. 
proimanthus resembles A. gilviflorus in its growth form and has a 
similar range of numbers of seeds in the fruits; however, unlike A. 
gilviflorus, it has narrow, oval-shaped fruit and short, differently 
shaped banner petals (Barneby 1964, p. 1154). The only other Astragalus 
species in Wyoming with three leaflets have smaller flowers than A. 
proimanthus (Fertig 1994, unpaginated). All species within the subgenus 
Oropahca have 12 chromosomes (Roberts 1977, p. 1), but it is unknown if 
they are interfertile (capable of cross-pollinating or breeding with 
other Astragalus species) (Fertig and Welp 2001, p. 14). No evidence of 
hybridization between A. proimanthus and other Astragalus species has 
been documented (Fertig and Welp 2001, p. 14). Based on this 
information, we recognize A. proimanthus as a valid species and a 
listable entity.

Biology and Life History

    Astragalus proimanthus (precocious milkvetch) is named for its 
early flowering period. It has been observed in flower as early as 
April 28, and it may continue to bloom until mid-June (Fertig and Welp 
2001, p. 14). Astragalus species are typically insect-pollinated; 
however, we have no information specific to A. proimanthus (Heidel 
2003, p. 19). Both insects and birds have been observed visiting the 
flowers of A. proimanthus and may be involved in pollination (Fertig 
and Welp 2001, p. 14). Fruits are continuously produced from mid-May 
through late July (Roberts 1977, pp. 43, 97). The narrow, oval fruit 
pods (7 to 10 mm (0.28 to 0.39 in.) long) are attached to the stems and 
are covered in dense, fine hair (Fertig and Welp 2001, p. 7). The fruit 
pods contain 11 to 14 seeds (Barneby 1964, p. 1154) that are brown and 
2.0 to 3.1 mm (0.08 to 0.12 in.) long (Roberts 1977, p. 64). Fruit 
production may be limited during drought years as evidenced by low 
fruiting rates observed in 2000 (Fertig and Welp 2001, p. 14). Due to 
the absence of seed structures (e.g., winged edges) to enhance 
dispersal, seed dispersal appears passive and limited to short 
distances (Fertig and Welp 2001, p. 14).
    Although Astragalus proimanthus is perennial, its lifespan may be 
shorter than is commonly assumed for mat-forming perennials, as is 
evidenced by shifts in location of plant subpopulations and 
disappearances of previously documented plant occurrences (Fertig and 
Welp 2001, pp. 13-14, 17). Longevity is an important life-history trait 
for the persistence and survival of species occurring in harsh 
environments where recruitment (reproductive success) is variable and 
unpredictable (Garcia et al. 2008, p. 261).

Habitat

    Astragalus proimanthus is a narrow endemic occurring only on the 
shale bluffs of the Henrys Fork River, near the town of McKinnon, which 
is in the southern Green River Basin of southwestern Sweetwater County, 
Wyoming (Fertig and Welp 2001, p. 8). Sparsely vegetated rims and 
gullied upper slopes of benches, bluffs, and mesa-like ridges at 
elevations of 1,950 to 2,195 m (6,400 to 7,200 ft) provide habitat for 
A. proimanthus (Fertig and Welp 2001, p. 11).
    Astragalus proimanthus inhabits cushion plant and bunchgrass 
communities dominated by Phlox hoodii (spiny phlox or carpet phlox), 
Haplopappus nuttallii (rayless aster), Cryptantha sericea (silky 
cryptantha), and Elymus spicatus (bluebunch wheatgrass) in openings 
within Artemisia tridentata (big sagebrush) and grasslands intermixed 
with Juniperus osteosperma (Utah juniper) (Fertig and Welp 2001, p. 
11). A. proimanthus also occurs on gentle slopes at the base of ridges 
within a matrix of Artemisia nova (black sagebrush), Sarcobatus 
vermiculatus (greasewood), J. osteosperma, and Grayia spinosa (spiny 
hopsage) (Fertig and Welp 2001, p. 11). This species grows in fine-
textured limestone shale clays that are dry, shallow, and covered by a 
dense layer of coarse cobbles, whitish flakey shale, and dark volcanic 
rock (Fertig and Welp 2001, pp. 11-12).
    Individual Astragalus proimanthus plants are often separated by 
apparently suitable, nonvegetated habitat, and typically occur in 
densities ranging from 0.18 to 3.4 plants per square meter (m\2\) (0.15 
to 2.8 plants per square yard (yd\2\)) (Fertig and Welp 2001, p. 14). 
The habitat in which A. proimanthus grows typically has less than 5 to 
10 percent vegetative cover (Fertig and Welp 2001, pp. 11-12). The 
absence of plants from seemingly suitable habitat may be the result of 
passive seed dispersal (addressed above) or episodic (occurring at 
irregular intervals) establishment events, such as gully washouts 
(Fertig and Welp 2001, p. 14).
    Average annual precipitation where Astragalus proimanthus occurs is 
25 cm (9.8 in.), with peak precipitation events occurring in May and 
June (Martner 1986 as cited in Fertig and Welp 2001, p. 12). Mean 
annual temperature is 4.4 [deg]C (40 [deg]F), with mean lows of -14.4 
[deg]C (6 [deg]F) in January, and mean highs of 28.9 [deg]C (84 [deg]F) 
in July (Martner 1986 as cited in Fertig and Welp 2001, p. 12). The 
average number of days per year at or below freezing are 225 (Martner 
1986 as cited in Fertig and Welp 2001, p. 12).

Distribution and Abundance

    The distribution of Astragalus proimanthus consists of 3 
populations which are made up of 26 subpopulations (Fertig and Welp 
2001, pp. 12-13; Heidel 2010a, pers. comm.). The largest population 
contains 21 subpopulations and occurs within 3.2 km (2 mi) of the 
Henrys Fork River along an 8-km (5-mi) stretch (WNDD in litt. 2010, 
unpaginated). The second largest population consists of four 
subpopulations and occurs 12.9 km (8 mi) further upstream on the Henrys 
Fork River, near the mouth of Cottonwood Creek (WNDD in litt. 2010, 
unpaginated). The smallest population consists of one subpopulation and 
occurs 2.5 km (1.5 mi) north of the largest population, along Lane 
Meadow Creek--a tributary to the Henrys Fork River (WNDD in litt. 2010, 
unpaginated). The entire distribution of A. proimanthus is limited to 
an area of less than 129.5 ha (320 ac) within an area of 6.4 by 22.5 km 
(4 by 14 mi) (Fertig and Welp 2001, p. 8).
    Population estimates of A. proimanthus have varied widely, probably 
reflecting variability in survey methods and discovery of new 
subpopulations (Fertig and Welp 2001, p. 13). In 1980, prior to the 
discovery of all 26 subpopulations, an estimated 200 plants were 
documented as occurring within 2 populations (Dorn 1980, p. 49). The 
first survey to inventory the entire known distribution was completed 
in May of 1981, with the total number of A. proimanthus plants 
estimated at 22,000 plants occurring on 97.1 ha (240 ac) (Whiskey Basin 
Consultants 1981, p. 5). Conclusions from field studies conducted in 
1989 are that, although the distribution of A. proimanthus was limited, 
subpopulations within that distribution were large, containing 
thousands of individual plants; the total population size was estimated 
at 25,000 to 40,000 individuals (Fertig and Welp

[[Page 33941]]

2001, p. 13). However, the 1989 field studies focused on identifying 
new subpopulations and initiating a monitoring program, not on 
conducting a quantitative census (Fertig and Welp 2001, p. 13). In June 
2000, a survey of 11 subpopulations representing the 3 known 
populations, conducted by the WNDD, resulted in a count of 2,644 
individuals; this was extrapolated to a minimum total population 
estimate of 10,500 to 13,000 individuals (Fertig and Welp 2001, p. 13).
    The distribution of A. proimanthus may be associated with the 
presence of a light-colored shale formation, where it is the uppermost 
soil layer (Whiskey Basin Consultants 1981, p. 9). The Henrys Fork 
River has eroded this shale formation away in some areas, causing it to 
be exposed over a distance of 9 km (5.5 mi) near the river (Whiskey 
Basin Consultants 1981, p. 9). Approximately 95 percent of the known 
occurrences of A. proimanthus have been found on BLM-administered 
lands, with 4 percent occurring on State lands, and 1 percent on 
private lands (Heidel 2010b, pers. comm.).
    The WNDD has designated Astragalus proimanthus as a plant species 
of concern with ranks of G1 and S1 (Heidel 2007, p. 3). For background 
information on G1 and S1 rankings, please refer to the last paragraph 
under Distribution and Abundance in the Species Information for Abronia 
ammophila section. Since A. proimanthus is endemic to Wyoming, the 
Wyoming occurrences encompass this species' entire global range.

Trends

    Population trends for Astragalus proimanthus are difficult to 
determine because survey methodologies have not remained consistent, 
baseline data are lacking, and precipitation has varied significantly 
during survey years (Fertig and Welp 2001, p. 13). Shifts in the 
distribution suggest that A. proimanthus may be shorter-lived than is 
often assumed for mat-forming perennials (Fertig and Welp 2001, p. 14). 
The importance of yearly fluctuations in precipitation and temperature 
to the establishment and survival of this species is unknown (Fertig 
and Welp 2001, p. 14).
    Population counts and distribution of Astragalus proimanthus along 
established transects have varied during the past two decades (Fertig 
and Welp 2001, p. 14). Five transects were established in 1989 to 
evaluate changes in abundance and density of plants (Marriott 1989, 
Appendix D). Surveys from two transects monitored from 1989 to 1998 
showed a long-term increase in numbers and densities of plants (Fertig 
and Welp 2001, pp. 37-47). However, numbers along a third transect 
decreased by 7 percent from 1989 to 1998, and then the transect could 
not be relocated in 2000 possibly due to a local extirpation of plants 
(Fertig and Welp 2001, pp. 14, 37-47). Surveys from the fourth transect 
showed a steady decline in overall plant numbers, reaching a 43 percent 
decrease in numbers by 2000 (Fertig and Welp 2001, pp. 14, 37-47). 
Surveys from the fifth transect revealed short-term oscillations in the 
population size, with numbers increasing between 1989 and 1998 and then 
decreasing 8 percent by 2000 (Fertig and Welp 2001, pp. 37-47). Changes 
in numbers and plant densities may be attributed to the short lifespans 
of individual plants or the lack of new plants becoming established 
(Fertig and Welp 2001, p. 14). Localized increases and decreases in 
population numbers and density may be expected for this species, as 
evidenced by the variable numbers and changes in spatial distributions 
along survey transects (Fertig and Welp 2001, p. 40). However, overall 
monitoring data suggest that the main population along the bluffs of 
the Henrys Fork River was relatively stable from 1998 to 2000 despite 
localized shifts in distribution (Fertig and Welp 2001, p. 14).

Five Factor Evaluation for Astragalus proimanthus

    Information pertaining to Astragalus proimanthus in relation to the 
five factors provided in section 4(a)(1) of the Act is discussed below.

Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range

    The following potential factors that may affect the habitat or 
range of Astragalus proimanthus are discussed in this section, 
including: (1) energy development, (2) road construction, (3) off-road 
vehicle use, (4) range improvements, (5) disposal sites, (6) nonnative 
invasive plants, (7) fire, and (8) climate change and drought.
Energy Development
    Energy development has been identified as a potential threat to 
Astragalus proimanthus (Marriot 1989, p. 8, Fertig and Welp 2001, p. 
16). The distribution of A. proimanthus is limited to Sweetwater 
County, Wyoming (WNDD in litt. 2010, unpaginated). Sweetwater County 
sits atop the coal seams and oil and gas reserves of the Upper Green 
River Basin, which by some estimates contain 10 percent of the nation's 
total onshore natural gas reserves, as well as the largest known trona 
(a source of sodium carbonate) deposit in the world (Headwaters 
Economics 2009, p. 26). Uranium and coal (Headwaters Economics, p. 26) 
as well as oil shale resources (Congressional Research Service 2008, p. 
3) occur throughout the county. There also is the potential for wind 
energy development in Sweetwater County (BLM 2010a, unpaginated).
    Oil and gas exploration and extraction; coal, uranium, and trona 
mining; and oil shale and wind energy development may involve ground-
disturbing actions that have the potential to remove or disturb 
Astragalus proimanthus and its habitat (Marriott 1989, p. 8; Fertig and 
Welp 2001, p. 16). Oil and gas exploration and coal mining may involve 
drilling, using explosives, driving heavy earth-moving equipment off 
road, clearing land for resource extraction or project infrastructures, 
and constructing roads and utility lines. Oil shale development may 
involve converting oil shale into crude oil through a process called 
destructive distillation, which may require land removal (Congressional 
Research Service 2008, p. 4). Wind energy development involves clearing 
land for constructing turbine sites and infrastructure including 
utility lines and roads. Additionally, all energy development may 
result in increased human use and vehicular traffic, which can result 
in trampling and increased erosion in the area.
    In 2000, seismic explorations took place near the mouth of 
Cottonwood Creek, where a population of Astragalus proimanthus occurs 
(Fertig and Welp, 2001, p. 16). Associated road construction may have 
disturbed A. proimanthus habitat, but there is no indication that 
plants were removed by these activities and any population-level 
effects are unknown. Presently, there is no ongoing energy development 
near the known occurrences of A. proimanthus on BLM-administered lands 
(Glennon 2010a, pers. comm.).
    Astragalus proimanthus is a special status species designated by 
the BLM State Director as sensitive (BLM 1997, p. 19). This status 
requires that potential habitat on Federal or split estate (i.e., mixed 
surface and mineral ownership) lands be searched to determine if 
sensitive plants are located in the project area before the project 
occurs (BLM 1997, p. 19). Areas with special status plant populations 
are closed to activities that would adversely affect them, including 
surface disturbances, locating new mining claims, mineral material 
sales, all off-road vehicle (ORV)

[[Page 33942]]

use, and use of explosives and blasting (BLM 1997, p. 19).
    In the Green River Resource Management Plan (RMP), the BLM has 
established a Special Status Plant Species Area of Critical 
Environmental Concern (ACEC) that covers four plant species including 
Astragalus proimanthus (BLM 1997, pp. 19, 34). This ACEC protects 100 
percent of A. proimanthus that occurs on BLM land (BLM 2011, 
unpaginated). This ACEC is closed to energy development activities that 
have the potential to adversely affect A. proimanthus and its habitat. 
Prohibited activities include surface disturbing activities and surface 
occupancy (such as leasable mineral exploration and development or 
construction of long-term facilities or structures), mineral material 
sales, and use of explosives and blasting (BLM 1997, pp. 19, 34). The 
ACEC has provisions by which any newly located A. proimanthus 
individuals and habitat can be added to the ACEC by an amendment to the 
RMP (BLM 1997, pp. 19, 34).
    Additionally, BLM-administered lands under a 48.6-ha (120-ac) 
fenced enclosure around one of the subpopulations of Astragalus 
proimanthus, north of the town of McKinnon, have been withdrawn from 
mineral exploration and mining (BLM 1999, p. 6; Glennon 2010a, pers. 
comm.). The BLM has committed to pursuing the withdrawal of mining 
claims in all areas of the Special Status Plants Species ACEC (BLM 
1997, p. 34).
    Although occurrences of Astragalus proimanthus on BLM-administered 
lands are protected from the impacts of energy development, future 
energy development remains a potential threat to occurrences of A. 
proimanthus that are not located on Federal land. However, this 
potential threat is unlikely to rise to the level of a threat to the 
species as the vast majority of known occurrences (95 percent) of A. 
proimanthus are located on BLM-administered lands (Heidel 2010b, pers. 
comm.; WNDD in litt. 2010, unpaginated). Therefore, we do not consider 
energy development to be a threat to A. proimanthus now or in the 
foreseeable future.
Road Construction
    Roads can destroy or modify habitat and increase human access that 
may lead to trampling or the introduction of nonnative invasive plants 
(discussed below). Additionally, road construction can lead to 
increased erosion, and vehicle traffic on unimproved roads can result 
in increased atmospheric dust and dust deposition on vegetation.
    Habitat for Astragalus proimanthus has been lost at several 
locations due to road construction (Fertig and Welp 2001, p 16). 
Wyoming State Highway 1 intersects two subpopulations (Fertig and Welp 
2001, p. 13). Several two-track vehicle trails are located near 
populations of A. proimanthus (BLM 1997, p. 199). During the summer of 
1993, BLM personnel documented surface disturbance due to traffic; this 
was partially associated with vehicles accessing the unauthorized 
McKinnon Dump, which is no longer in use and has since been reclaimed 
(BLM 1997, p. 199).
    On BLM lands, special status plant populations are closed to 
activities that could adversely affect them or their habitat (BLM 1997, 
p. 19), and the ACEC is closed to all direct surface-disturbing road 
construction (BLM 1997, p. 34). Future road development is a potential 
threat to occurrences of Astragalus proimanthus that are not on BLM-
managed lands. However, future road construction does not rise to the 
level of a threat to A. proimanthus, because the species primarily 
occurs on BLM-administered lands and, therefore, is protected by the 
provisions in the ACEC and its designation as a special status plant 
species (BLM 1997, pp. 19, 34). Therefore, we do not consider road 
construction to be a threat to A. proimanthus now or in the foreseeable 
future.
Off-Road Vehicle Use
    The use of ORVs is both a means of transportation and recreation in 
Wyoming. Approximately 35.5 percent of Wyoming's 506,000 residents use 
ORVs for recreational purposes (Foulke et al. 2006, p. 3). During 2004 
and 2005, Sweetwater County had the fifth highest ORV permit sales in 
the State (Foulke et al. 2006, pp. 8-9).
    The area of BLM-administered land in Sweetwater County, Wyoming, 
where Astragalus proimanthus occurs has not experienced the high level 
of ORV use seen in some other areas of Wyoming (Glennon 2010a, pers. 
comm.). There are no large communities nearby to support local ORV 
recreational activities. The closest town (within 3.2 km (2 mi) of the 
nearest populations of A. proimanthus) is McKinnon, with a population 
of 49 in 2000 (U.S. Census Bureau 2010, unpaginated). The larger 
communities of Green River (estimated population of 12,411 in 2009), 
Rock Springs (estimated population of 20,905 in 2009), and Evanston 
(estimated population of 11,958 in 2009) (U.S. Census Bureau 2009, 
unpaginated) are 78.9, 106.2, and 120.7 km (49, 66, and 75 mi) from 
McKinnon, respectively. There are many ORV opportunities closer to 
these communities than those on the BLM-administered lands near the 
town of McKinnon.
    In addition, Astragalus proimanthus habitat is generally not 
attractive to ORV users. Recreational destinations in the area where A. 
proimanthus occurs are largely limited to a few historic sites and 
trails (BLM 1997, pp. 4-6). Available two-track vehicle trails provide 
access to most common destinations, such as water sources and hunting 
campsites, so that off-road access is not often necessary (Glennon 
2010a, pers. comm.). Additionally, A. proimanthus occurs on slopes and 
ridges (Fertig and Welp 2001, p. 11) that are not conducive to ORV 
travel that is destination-oriented.
    Finally, the ACEC is closed to ORV use (BLM 1997, p. 72). However, 
there are no physical barriers to keep ORVs out of the ACEC, except for 
in the 48.6-ha (120-ac) fenced exclosure (Glennon 2010a, pers. comm.). 
At other locations in southwestern Wyoming, violators of BLM and U.S. 
Forest Service travel restrictions on ORV use have been reported (WGFD 
2010, unpaginated). The potential for impacts from illegal ORV use on 
BLM-administered lands is possible even within the ACEC. However, 
impacts from illegal ORV use are unlikely due to the low human 
populations in the area, the difficulty of traversing the habitats 
occupied by Astragalus proimanthus, and the greater likelihood of 
enforcement of the prohibition of ORV use within an ACEC due to 
critical resource concerns (BLM 1997, p. 110). Therefore, we do not 
consider ORV use to be a threat to A. proimanthus now or in the 
foreseeable future.
Range Improvements
    Habitat modifications due to range improvement projects for 
livestock have been identified as a potential threat to Astragalus 
proimanthus (Marriott 1989, p. 8). However, this was prior to the 
designation of the ACEC that provides special protections for A. 
proimanthus (BLM 1997, p. 34). As stated in the Green River RMP, within 
the ACEC: ``Livestock grazing objectives and management practices will 
be evaluated and, as needed, modified to be consistent with the 
management objectives for this area'' (BLM 1997, p. 34). The plan also 
specifies, ``Grazing systems will be designed to achieve desired plant 
communities and proper functioning conditions of watersheds (upland and 
riparian)'' (BLM 1997, p. 34). Additionally, no wild horse traps will 
be constructed within this area (BLM 1997, p. 34). Movement of

[[Page 33943]]

livestock between areas of known use and range improvements will be 
evaluated and monitored, and locations of range improvements will be 
modified, if necessary, to ensure that the habitat where A. proimanthus 
occurs will not be trampled (Glennon 2010a, pers. comm.). The fact that 
populations from 1989 through 2000 were relatively stable (Fertig and 
Welp 2001, p. 14) suggests that range management did not adversely 
affect A. proimanthus populations during that time. No impacts from 
livestock have been noted recently (Glennon 2010a, pers. comm.). Since 
1997, range management practices also are evaluated pursuant to the 
management objectives of the ACEC (BLM 1997, p. 19). Additionally, 
known locations of A. proimanthus are protected and closed to surface-
disturbing activities or any disruptive activity that could adversely 
affect the plants or their habitat (BLM 1997, p 19). Therefore, we do 
not consider range improvements to be a threat to A. proimanthus now or 
in the foreseeable future.
Disposal Sites
    Disturbance associated with garbage disposal sites (dumps) has been 
identified as a potential threat to Astragalus proimanthus (Marriott 
1989, p. 8). Surveys conducted by the BLM in 1993 and 1994 documented 
disturbances to the habitat of A. proimanthus due to the presence of 
the McKinnon Dump (BLM 1997, p. 199). The McKinnon Dump was an illegal 
dump located on BLM land (Board of County Commissioners of Sweetwater 
County 1992, unpaginated). The BLM and Sweetwater County worked 
together to clean up and reclaim the McKinnon Dump (Board of County 
Commissioners of Sweetwater County 1992, unpaginated; BLM 1997, p. 
199). Since 1997, the ACEC appears to have effectively protected A. 
proimanthus from surface disturbance, such as dumps, on BLM-
administered lands (BLM 1997, p. 34). Therefore, we do not view 
disposal sites to be a threat to A. proimanthus now or in the 
foreseeable future.
Nonnative Invasive Plants
    For general background information on nonnative invasive plants, 
please refer to the first paragraph of ``Nonnative Invasive Plants'' 
under Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range in the Five Factor Evaluation for 
Abronia ammophila section.
    We have no evidence of impacts to Astragalus proimanthus from 
nonnative invasive plants. A. proimanthus grows in shallow, dry soils 
that support only sparse vegetation (Fertig and Welp 2001, pp. 11-12). 
The characteristics of its harsh habitat may explain why no nonnative 
invasive plants have been reported in proximity to the known 
occurrences. Therefore, we do not consider nonnative invasive plants to 
be a threat to this species now or in the foreseeable future.
Fire
    We find the potential impact of wildfire to the species to be 
minimal due to the sparse vegetation cover in habitats occupied by 
Astragalus proimanthus. From 1980 through 2009 (29 years), seven 
wildfires occurred in the area BLM mapped as potential habitat for 
Astragalus proimanthus (Caldwell 2011, pers. comm.). However, no fires 
burned in areas with known occurrences of A. proimanthus; moreover, the 
total acreage burned during this 29-year period was 0.3 ha (0.7 ac) 
(Caldwell 2011, pers. comm.). All seven wildfires were caused by 
lightning strikes to isolated junipers, and only that individual tree 
burned (Stephenson 2011, pers. comm.). Areas of barren ground between 
widely spaced vegetation and low fuel loads prevent fires from 
spreading far beyond points of ignition (Brooks and Pyke 2002, p. 5), 
as the existence of adequate fuels is one of the requirements for a 
fire to start and continue to burn (Moritz Lab 2010, entire). 
Therefore, we do not consider fire to be a threat to this species now 
or in the foreseeable future.
Climate Change and Drought
    For general background information on climate change, please refer 
to the first paragraphs of ``Climate Change'' under Factor A. The 
Present or Threatened Destruction, Modification, or Curtailment of Its 
Habitat or Range in the Five Factor Evaluation for Abronia ammophila 
section.
    Although assessing the magnitude and type of effect climate change 
may have on Astragalus proimanthus is complex, we believe climate 
change has the potential to affect the species given the predictions 
discussed previously of increased springtime temperatures, decreased 
springtime precipitation, and increased drought. The importance of 
yearly fluctuations in precipitation and temperature on the 
establishment and survival of A. proimanthus is unknown (Fertig and 
Welp 2001, p. 14). However, drought is not unusual or unnatural in 
Wyoming. Severe or extreme drought conditions occur more than 20 
percent of the time over the southwestern regions of the State (Curtis 
and Grimes 2004, Chapter 6.2). As noted previously, monitoring data 
suggest that the main population along the bluffs of the Henrys Fork 
River was relatively stable from 1998 to 2000 (Fertig and Welp 2001, p. 
14). During this same period, this species' habitat experienced drought 
conditions, including severe droughts (Curtis 2004, unpaginated). 
Although climate change may affect the duration and severity of drought 
in some locations, we do not have information to suggest A. proimanthus 
is unlikely to be able to respond to this potential stressor. 
Therefore, we do not consider climate change and drought to be a threat 
to this species now or in the foreseeable future.
Summary of Factor A
    Occurrences of Astragalus proimanthus have experienced historical 
impacts from road development and illegal trash dumps. Additionally, 
seismic exploration for oil and gas occurred near one population where 
associated road construction may have disturbed A. proimanthus habitat, 
but there is no indication that plants were destroyed. Currently, the 
habitat disturbance due to the McKinnon dump has effectively been 
addressed. The special species status of A. proimanthus and the 
provisions in the ACEC are adequate to alleviate the threats to A. 
proimanthus from energy development, road construction, ORV use, range 
improvements, and other land uses that have the potential to disturb 
the habitat of A. proimanthus. Although potential threats on State and 
private lands may exist, such as ORV use or range improvements, only 5 
percent of this species' distribution occurs on private lands, and no 
impacts to the species on private lands has been documented.
    In summary, we note that procedural considerations for amending the 
Green River RMP to ensure that all individual Astragalus proimanthus 
plants on BLM-administered lands are protected by the Special Status 
Plant Species ACEC (BLM 1997, pp. 19-20, 34) are lengthy and may not 
accurately delineate the oscillating distributions and new discoveries 
of this species. However, maintenance actions may be used in certain 
situations including new population discoveries and species' range 
shifts (see Factor D: Bureau of Land Management below). Therefore, we 
find that the protections provided by the special status plant species 
designation (BLM 1997, p. 19) in combination with the protections 
provided by the Special Status Plant ACEC, as documented in the Green 
River RMP (BLM 1997, p. 34), provide

[[Page 33944]]

effective protection to 95 percent of the population of A. proimanthus.
    We conclude that the best scientific and commercial information 
available indicates that Astragalus proimanthus is not in danger of 
extinction or likely to become so within the foreseeable future because 
of the present or threatened destruction, modification, or curtailment 
of its habitat or range.

Factor B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    Astragalus proimanthus is not known to be collected for any 
purposes. One species of this genus, Astragalus membranaceus (Huang 
qi), has been used in traditional Chinese medicine for thousands of 
years (University of Maryland 2006, unpaginated). However, this species 
is native to Asia, and Astragalus species that grow in the United 
States do not share similar medicinal properties (University of 
Maryland 2006, unpaginated). We have no information to indicate that A. 
proimanthus is threatened by overutilization for commercial, 
recreational, scientific, or educational purposes.
    We conclude that the best scientific and commercial information 
available indicates that Astragalus proimanthus is not in danger of 
extinction or likely to become so within the foreseeable future because 
of overutilization for commercial, recreational, scientific, or 
educational purposes.

Factor C. Disease or Predation

Disease
    Astragalus proimanthus is not known to be affected or threatened by 
any disease. Therefore, we do not consider disease to be a threat to A. 
proimanthus now or in the foreseeable future.
Predation--Grazing and Herbivory
    Grazing and herbivory effects on Astragalus proimanthus have not 
been studied. Bird or insect predation on many A. proimanthus flowers 
was noted on at least one occasion (Barneby 1964, p. 1154). Most 
occurrence reports do not mention any instances of herbivory (WNDD in 
litt. 2010, unpaginated; Marriot 1989, p. 16). Domestic sheep 
apparently do not graze A. proimanthus (Mutz 1981, p. 6), and direct 
impacts from grazing are thought to be unlikely due to the plant's low 
stature, coarse pubescence (fine, short hairs), and low palatability 
(Mutz 1981, p. 6; Marriott 1989, unpaginated; Fertig and Welp 2001, p. 
14). Therefore, we do not consider predation to be a threat to A. 
proimanthus now or in the foreseeable future.
Summary of Factor C
    We conclude that the best scientific and commercial information 
available indicates that Astragalus proimanthus is not in danger of 
extinction or likely to become so within the foreseeable future because 
of disease or predation.

Factor D. The Inadequacy of Existing Regulatory Mechanisms

    The Act requires us to examine the adequacy of existing regulatory 
mechanisms with respect to threats that may place Astragalus 
proimanthus in danger of extinction or likely to become so in the 
future. Existing regulatory mechanisms that could have an effect on 
potential threats to A. proimanthus include (1) Federal laws and 
regulations; (2) State laws and regulations; and (3) local land use 
laws, processes, and ordinances. Most (95 percent) of A. proimanthus 
occurs on Federal land; therefore, the discussion below focuses on 
Federal laws. Actions adopted by local groups, States, or Federal 
entities that are discretionary, including conservation strategies and 
guidance, are not regulatory mechanisms; however, we may discuss them 
in relation to their effects on potential threats to the species.
Federal Laws and Regulations
Bureau of Land Management
    As discussed previously, the special status species designation and 
the Special Status Plant Species ACEC, as documented in the Green River 
RMP (BLM 1997, pp. 19, 34), have adequate provisions to effectively 
protect 95 percent of the population distribution of Astragalus 
proimanthus. An RMP, the primary management tool that implements 
regulatory mechanisms, goes through revisions approximately every 15 
years, and a revision to the Green River RMP is anticipated by 2013 
(Dana 2010b, pers. comm.). This revision has been started and the 
special status plant designation, based on the BLM State Directors' 
designation, will carry over into the newly revised RMP.
    Astragalus proimanthus was designated by the BLM State Director as 
a BLM State-sensitive species (BLM 2010b, p. 23). The BLM focuses 
sensitive species management on maintaining species habitat in 
functional ecosystems, ensuring the species is considered in land 
management decisions, preventing a need to list the species under the 
Act, and prioritizing conservation that emphasizes habitat (BLM 2010b, 
p. 1). The BLM sensitive species are automatically included as special 
status plant species, along with candidate, threatened, and endangered 
plant species (BLM 1997, p. 19), and locations of special status plant 
species are closed to activities that could adversely affect them or 
their habitat (BLM 1997, p. 19). Additionally, the ACEC delineates 
known distributions of A. proimanthus and its essential habitat, while 
furthering the protection of newly discovered locations on BLM lands 
(BLM 1997, p. 34). The BLM conducts searches to identify additional 
areas where A. proimanthus may be located (BLM 1997 p. 34). In January 
2011, the BLM took a maintenance action on the Green River RMP to 
include all newly discovered locations of A. proimanthus on BLM-
administered lands in the ACEC (BLM 2011, unpaginated). Maintenance 
actions are based on new or changed data, and document or refine 
previously approved decisions incorporated into an RMP (43 CFR 1610.5-
4). A maintenance action does not require formal public involvement and 
interagency coordination as this action is limited to refining or 
documenting a previously approved decision incorporated in the plan (43 
CFR 1610.5-4). As a result of this maintenance action 100 percent of 
the known locations of A. proimanthus occurring on BLM-administered 
lands are protected by the ACEC (BLM 2011, unpaginated).
National Environmental Policy Act
    All Federal agencies are required to adhere to the NEPA for 
projects they fund, authorize, or carry out. For more information about 
NEPA, please refer to Factor D. The Inadequacy of Existing Regulatory 
Mechanisms in the Five Factor Evaluation for Abronia ammophila section.
State and Local Laws and Regulations
    The remaining 5 percent of the distribution of A. proimanthus 
occurs on State and private lands, and are not protected by regulatory 
mechanisms.
Summary of Factor D
    The existing ACEC appears to adequately protect the majority (95 
percent) of the habitat of Astragalus proimanthus. We expect that A. 
proimanthus and its habitat will be generally protected from direct 
human disturbance. We have no evidence of impacts to A. proimanthus 
from inadequate regulatory mechanisms.
    We conclude that the best scientific and commercial information 
available indicates that Astragalus proimanthus is not in danger of 
extinction or likely to become so within the foreseeable future because 
of inadequate regulatory mechanisms.

[[Page 33945]]

Factor E. Other Natural or Manmade Factors Affecting Its Continued 
Existence

    Natural and manmade factors with the potential to affect Astragalus 
proimanthus include: (1) Small population size, (2) pollination, and 
(3) genetic diversity.
Small Population Size
    For background information, please refer to the first paragraph of 
``Small Population Size'' under Factor E. Other Natural or Manmade 
Factors Affecting Its Continued Existence in the Five Factor Evaluation 
for Abronia ammophila section.
    We have no evidence that the populations of Astragalus proimanthus 
are experiencing the problems that occur in some species with small 
population size. We do not have any indication that A. proimanthus was 
ever present on the landscape over a more extensive range. We also have 
no information indicating that random demographic or environmental 
events are a threat to the species because of its small population 
size. Therefore, we do not consider small population size to be a 
threat to A. proimanthus now or in the foreseeable future.
Pollination
    Please refer to the first paragraph of ``Pollination'' under Factor 
E. Other Natural or Manmade Factors Affecting Its Continued Existence 
in the Five Factor Evaluation for Abronia ammophila section for 
background information. Astragalus proimanthus is believed to have been 
historically rare, with populations appearing to be stable (Fertig and 
Welp 2001, p. 13). We have no information indicating that a lack of 
pollinators is a threat to the species. Therefore, we do not consider 
lack of pollinators to be a threat to A. proimanthus now or in the 
foreseeable future.
Genetic Diversity
    For background information, please refer to the first paragraph of 
``Genetic Diversity'' under Factor E. Other Natural or Manmade Factors 
Affecting Its Continued Existence in the Five Factor Evaluation for 
Abronia ammophila section. We have no information indicating that a 
lack of genetic diversity is a threat to the species. Therefore, we do 
not consider lack of genetic diversity to be a threat to A. proimanthus 
now or in the foreseeable future.
Summary of Factor E
    We have no information to suggest that Astragalus proimanthus was 
ever present across the landscape with a broader range. We have no 
indication that A. proimanthus is suffering from any problems 
associated with small population size. We also have no information 
showing that A. proimanthus is suffering from low pollination rates or 
reduced genetic diversity. Therefore, we conclude that the best 
scientific and commercial information available indicates that 
Astragalus proimanthus is not in danger of extinction or likely to 
become so within the foreseeable future because of small population 
size, reduced pollination, or reduced genetic diversity.

Finding

    As required by the Act, we considered the five factors in assessing 
whether Astragalus proimanthus is threatened or endangered throughout 
all of its range. We examined the best scientific and commercial 
information available regarding the past, present, and future threats 
faced by the species. We reviewed the petition, information available 
in our files, other available published and unpublished information, 
and we consulted other Federal and State agencies.
    Occurrences of Astragalus proimanthus experienced historical 
impacts from road development and illegal trash dumps. Additionally, 
seismic exploration for oil and gas occurred near one population, with 
no known impacts to the species. However, the provisions in the ACEC 
now in place are adequately alleviating any potential threats to A. 
proimanthus from energy development, road construction, ORV use, range 
improvements, and other land uses that have potential to disturb A. 
proimanthus and its habitat. Although potential threats on State and 
private lands exist, such as ORV use or range improvements, no impacts 
to the plants on these lands have been documented or are reasonably 
anticipated. We have no information to show that A. proimanthus is 
threatened by overutilization for commercial, recreational, scientific, 
or educational purposes at this time. We conclude that the best 
scientific and commercial information available indicates that 
Astragalus proimanthus is not in danger of extinction or likely to 
become so within the foreseeable future because of climate change, 
drought, nonnative invasive plants, fire, small population size, lack 
of pollinators, or reduced genetic diversity. We have no information 
regarding actual or potential adverse impacts due to overutilization, 
disease, inadequate regulatory mechanisms, reduced genetic diversity, 
or reduced pollination.
    Based on our review of the best available scientific and commercial 
information pertaining to the five factors, we find that the threats 
are not of sufficient imminence, intensity, or magnitude to indicate 
that Astragalus proimanthus is in danger of extinction (endangered), or 
likely to become endangered within the foreseeable future (threatened), 
throughout all of its range. Therefore, we find that listing A. 
proimanthus as a threatened or endangered species is not warranted 
throughout all of its range.

Significant Portion of the Range

    Having determined that Astragalus proimanthus does not meet the 
definition of a threatened or endangered species, we must next consider 
whether there are any significant portions of the range where A. 
rossiae is in danger of extinction or is likely to become endangered in 
the foreseeable future.
    In determining whether Astragalus proimanthus is threatened or 
endangered in a significant portion of its range, we first addressed 
whether any portions of the range of A. proimanthus warrant further 
consideration. We evaluated the current range of A. proimanthus to 
determine if there is any apparent geographic concentration of the 
primary stressors potentially affecting the species including energy 
development, road construction, ORV use, range improvements, and other 
land uses. This species' small range suggests that stressors are likely 
to affect it in a uniform manner throughout its range. However, we 
found the stressors are not of sufficient imminence, intensity, 
magnitude, or geographically concentrated such that it warrants 
evaluating whether a portion of the range is significant under the Act. 
We do not find that A. proimanthus is in danger of extinction now, nor 
is likely to become endangered within the foreseeable future throughout 
all or a significant portion of its range. Therefore, listing A. 
proimanthus as threatened or endangered under the Act is not warranted 
at this time.
    We request that you submit any new information concerning the 
status of, or threats to, Astragalus proimanthus to our Wyoming 
Ecological Services Field Office (see ADDRESSES section) whenever it 
becomes available. New information will help us monitor A. proimanthus 
and encourage its conservation. If an emergency situation develops for 
A. proimanthus, or any other species, we will act to provide immediate 
protection.

[[Page 33946]]

Species Information for Penstemon gibbensii

Species Description

    Penstemon gibbensii is a perennial forb (herbaceous plant that is 
not a grass) averaging approximately 23 cm (9 in.) in height (Dorn 
1990a, p. 3). Its leaves are long and narrow, often folded down the 
length of the mid-rib, pubescent (covered with fine, short hairs) to 
smooth, and typically less than 5 mm (0.2 in.) wide (Fertig and 
Neighbours 1996, p. 4). Populations at lower elevations are 
conspicuously more pubescent, possibly as an adaptation to conserve 
moisture in warmer habitats (Dorn 1990a, p. 6). The bright blue flower 
is tube-shaped, 15 to 20 mm (0.6 to 0.8 in.) long, and may appear from 
early June to September, depending on moisture levels (Fertig 2000d, 
unpaginated).

Taxonomy

    Penstemon, with an estimated 271 species, is the largest plant 
genus endemic to North America, and the Intermountain Region represents 
the center of diversity (Wolfe et al. 2006, p. 1699). In the early 
1970s, Robert Gibbens collected the first specimens of Penstemon 
gibbensii in Sweetwater County, Wyoming (Dorn 1982, p. 334). These 
specimens were sent to a Penstemon specialist for identification and 
subsequently lost (Dorn 1990a, p. 1). In 1981, Robert Dorn resurveyed 
the area and relocated P. gibbensii in the field (Dorn 1982, p. 334; 
Heidel 2009, p. 1). P. gibbensii was determined to be a new, 
undescribed species based on its morphology (Dorn 1982, p. 334; Fertig 
and Neighbours 1996, pp. 4-6). This species has been reproductively 
isolated for some time as each known population of P. gibbensii 
exhibits slight morphological and habitat differences (Dorn 1989 as 
cited in Fertig and Neighbours 1996, pp. 3-4).
    Penstemon gibbensii is a member of the Scrophulariaceae (figwort or 
snapdragon) family (Dorn 1982, p. 334; Fertig and Neighbours 1996, p. 
2). Similar species include Penstemon cyananthus (Wasatch beardtongue), 
Penstemon fremontii (Fremont's beardtongue), Penstemon saxosorum 
(upland beardtongue), and Penstemon scariosus (White River beardtongue) 
(Fertig 2000d, unpaginated). P. gibbensii, which occurs at a lower 
elevation than P. saxosorum, can be distinguished by stems that are 
pubescent nearly to the base, narrower leaves, and corollas (all the 
petals of the flower) that are pubescent inside and out (Dorn 1982, p. 
334). P. gibbensii is more pubescent than P. cyananthus, and has much 
narrower leaves (Dorn 1982, p. 334). The current taxonomic status of P. 
gibbensii is accepted (Integrated Taxonomic Information System 2010b, 
unpaginated). We recognize P. gibbensii as a valid species and a 
listable entity.

Biology and Life History

    Reproduction of Penstemon gibbensii is by seed, with no evidence of 
vegetative reproduction (Fertig and Neighbours 1996, p. 16). Based upon 
flower color and shape, this species is probably insect pollinated 
(Fertig and Neighbours 1996, p. 16). Bees have been seen visiting 
flowers at sites in Colorado and Utah (Langton 2010, pers. comm.). 
Fruits are oval, light-brown capsules (Fertig 2000d, unpaginated). 
Seeds are probably dispersed primarily by gravity or wind (Fertig and 
Neighbours 1996, p. 16). P. gibbensii appears to have minimal 
reproductive success, as evidenced by below-normal seedling numbers in 
most years due to dry conditions (Heidel 2009, p. 21). In 1985, 1988, 
and 1991, at three transects in the Cherokee Basin occurrence, 0 to 56 
percent of P. gibbensii plants were seedlings (Warren in litt. 1992, 
Table 2). Seedling establishment is probably episodic and dependent on 
occasional years with adequate summer moisture (Fertig and Neighbours 
1996, p. 16). P. gibbensii is able to take advantage of summer 
precipitation, as it is a warm-season species (Warren in litt. 1992, 
unpaginated).
    No information was available regarding chilling requirements for 
seeds of P. gibbensii. However, close relatives (i.e., Penstemon 
cyananthus, Penstemon fremontii, and Penstemon scariosus) have seeds 
that are largely dormant at harvest and require a long chilling period 
prior to germination (Meyer and Kitchen 1994, p. 354). These species 
have evolved seed germination mechanisms that permit the carryover of 
seeds between years as a persistent seed bank, which maximizes the 
probability of seedling survival in favorable years (Meyer and Kitchen 
1994, p. 363). Recognizing the similarities between these Penstemon 
species and their climatic conditions, we assume that P. gibbensii also 
requires a chilling period and has a persistent seed bank.

Habitat

    Penstemon gibbensii occurs in a cold steppe climate on barren shale 
or sandy-clay slopes (Dorn 1990a, p. 6). Habitat is often located on 
steep upper or middle slopes eroding below a more resistant caprock 
(Heidel 2009, p. 13). Slopes are generally 20 to 30 degrees and 
predominately south- or west-facing (Dorn 1990a, p. 8). These 
conditions reduce percolation (water seeping into the ground) and 
increase evaporation (Heidel 2009, p. 20). P. gibbensii has been 
reported at elevations from 1,634 to 2,347 m (5,360 to 7,700 ft) (Dorn 
1990a, p. 5; CNHP 2010a, unpaginated). Soils are typically highly 
erodible, with low nutrient levels, low soil moisture, and high 
selenium content (Spackman and Anderson 1999, p. 3).
    Biological soil crusts are well-developed in Penstemon gibbensii 
habitat in Colorado and Utah, but were not noted at any sites in 
Wyoming (Heidel 2009, p. 14). Biological soil crusts are commonly found 
in semiarid and arid environments such as the Great Basin and Colorado 
Plateau, and are formed by a community of living organisms that can 
include cyanobacteria, green algae, microfungi, mosses, liverworts, and 
lichens (USGS 2006, unpaginated). These crusts provide many positive 
benefits for the larger biotic community including decreased erosion, 
improved water infiltration, increased seed germination, and improved 
plant growth (Spackman and Anderson 1999, p 3; USGS 2006, p. 2).
    Penstemon gibbensii exploits a largely barren, challenging 
environment (Dorn 1990a, p. 3). This species is generally not tolerant 
of competition from other species or other Penstemon plants; individual 
plants are usually spaced one to several meters (3 or more ft) apart 
(Dorn 1990a, pp. 8-9). Total vegetative cover is typically 5 to 10 
percent (Fertig 2000, p. 2). Associated species include Elymus spicatus 
(bluebunch wheatgrass), Achnatherum hymenoides (Indian ricegrass), 
Herperostipa comata (needle-and-thread grass), Eriogonum brevicaule 
(shortstem wild buckwheat), Eremogone hookeri (Hooker's sandwort), and 
Minuartia nuttallii (Nuttall's stitchwort) (Heidel 2009, p. 13). 
Adjacent vegetative communities may include pinyon-juniper woodlands, 
sagebrush shrublands, or greasewood-saltbush shrublands (Dorn 1990a, p. 
9).

Distribution

    Penstemon gibbensii is a regional endemic, with a range that 
includes Carbon and Sweetwater Counties in Wyoming, Moffat County in 
Colorado, and Daggett County in Utah (Dorn 1990a, p. 6; Heidel 2009, p. 
31). P. gibbensii was not recognized as a new species until 1981 (Dorn 
1982, p. 334; Fertig and Neighbours 1996, pp. 4-6). Consequently, its 
historical range is unknown. However, P. gibbensii was possibly always 
uncommon (Heidel 2009, pp. 5, 8). The species is currently known from 
nine occurrences including: Cherokee Basin, Sand Creek,

[[Page 33947]]

Flat Top Mountain, T84N R18W, Willow Creek, and Red Creek Rim in 
Wyoming; Spitzie Draw and Sterling Place in Colorado; and Dagget 
County, Utah. These nine occurrences are spread across 193 km (120 mi) 
and occupy approximately 109 ha (270 ac) in Wyoming, 10 ha (25 ac) in 
Colorado, and 2 ha (5 ac) in Utah (Heidel 2009, p. 31). Three of the 
six Wyoming occurrences and the Colorado and Utah occurrences are 
within 5 to 8 km (3 to 5 mi) of each other (Heidel 2009, p. 9). In 
Wyoming, surveys for additional occurrences have been conducted in over 
100 sections (each section is 259 ha (640 ac)), primarily along the 
Carbon-Sweetwater County line (Heidel 2009, p. 12). Additional 
potential habitat also has been searched in Moffat County, Colorado, 
and in Daggett County, Utah; no new populations have been found in 
these areas (Dorn 1990a, p. 6; Spackman and Anderson 1999, p. 31).
    Most known Penstemon gibbensii (approximately 77 percent) occur on 
State and Federal land. All Wyoming occurrences, with the exception of 
the T84N R18W occurrence and a small portion of the Sand Creek 
occurrence are on land managed by BLM (Heidel 2009, p. 27). The Nature 
Conservancy (TNC) manages the T84N R18W occurrence, which is on State 
and private land (Heidel 2009, p. 31). A small portion of the Sand 
Creek occurrence also is on State land (Heidel 2009, p. 27). In 
Colorado, the Spitzie Draw occurrence is on Browns Park National 
Wildlife Refuge (NWR) (managed by the Service) and BLM land, and the 
Sterling Place occurrence is on BLM land. The Daggett County, Utah, 
occurrence is on State land (Heidel 2009, p. 27). Management 
responsibilities are described in Table 2 below.

Abundance

    Table 2 presents available information regarding the known 
occurrences of Penstemon gibbensii. The plant numbers and occupied 
habitat do not sum to the exact current total due to slight differences 
between references. Most estimates are based on walking surveys through 
occupied habitat; two sites (Cherokee Basin and Flat Top Mountain) also 
have permanent transects for trend monitoring (Heidel 2009, Appendix 
B).

                                Table 2--Known Occurrences of Penstemon Gibbensii
----------------------------------------------------------------------------------------------------------------
                                       Estimated plant numbers
Species occurrence  (year identified)      (year surveyed)          Occupied habitat            Management
----------------------------------------------------------------------------------------------------------------
Cherokee Basin, WY (1981)............  450 (1985).............  6.2 ha (15.2 ac).......  BLM-Rawlins Field
                                                                                          Office.
                                       1,400 (1988)
                                       2,766 (1991)...........
                                       1,000 (1995)...........
                                       50-100 (2007)..........
Sand Creek, WY (1987)................  2,000 (1989)...........  48.1 ha (118.7 ac).....  BLM-Rawlins Field
                                       1,900-2,000 (1995).....                            Office and State of
                                       3,000 (2005)...........                            WY.
 
Flat Top Mountain, WY (1987).........  300 (1989).............  7.2 ha (17.9 ac).......  BLM-Rawlins Field
                                       1,000-1,200 (1995).....                            Office.
                                       300 (2008).............
 
T84N R18W, WY (1997).................  4,500-5,000 (1999).....  28.8 ha (71.2 ac)......  TNC.
                                       500-1,000 (2008).......
Willow Creek, WY (2004)..............  2,200 (2008)...........  15.6 ha (38.5 ac)......  BLM-Rawlins Field
                                                                                          Office.
Red Creek Rim, WY (2008).............  120 (2008).............  3.3 ha (8.1 ac)........  BLM-Rawlins Field
                                                                                          Office.
Spitzie Draw, CO (1982)..............  263 (2009).............  ~5 ha (12 ac)..........  Service-Browns Park
                                                                                          NWR.
                                                                                         BLM-Little Snake Field
                                                                                          Office.
Sterling Place, CO (1984)............  656 (2010).............  ~4 ha (9 ac)...........  BLM-Little Snake Field
                                                                                          Office.
Daggett County, UT (1989)............  300 (2010).............  5 ha (12 ac)...........  State of UT.
                                      --------------------------------------------------
    Current Total....................  ~11,000-14,000.........  ~122 ha (300 ac)
----------------------------------------------------------------------------------------------------------------
Table 2 References: Heidel 2009, pp. 22, 31; CNHP in litt. 2009a, p. 2; in litt. 2009b, p. 2; in litt. 2010a, p.
  2.

    The Colorado Natural Heritage Program (CNHP) has designated 
Penstemon gibbensii as a plant species of special concern (CNHP 2010b, 
unpaginated). The WYNDD also has designated P. gibbensii as a plant 
species of concern (Heidel 2007, p. 18). The Utah Native Plant Society 
ranks P. gibbensii as a rare plant of ``extremely high priority'' (Utah 
Rare Plants 2010, unpaginated). These designations are typically based 
on TNC's natural heritage State rank. P. gibbensii is ranked S1 in all 
three States because of its extreme rarity. These designations indicate 
that particular consideration may be taken by the States with regard to 
management decisions potentially affecting P. gibbensii, but do not 
result in any regulatory protection for the species.

Trends

    Long-term population trend data for Penstemon gibbensii is not 
available. Short-term trends can be examined at four of the nine 
occurrences, where population estimates are available for more than 1 
year (see Table 1). Only a single population estimate is available from 
the two most recently discovered sites in Wyoming and the three sites 
in Colorado and Utah. Short-term trends for the three Wyoming 
populations of P. gibbensii that have been surveyed more frequently 
were described as stable to slightly increasing in 2000; this was 
attributed to favorable climatic conditions in the preceding years 
(Fertig 2000d, unpaginated). Since 2000, populations appear to be 
stable to increasing at the Sand Creek occurrence and declining at the 
other three Wyoming sites. Seedling establishment is probably episodic 
(occurring at irregular intervals) and dependent on rare years of 
adequate summer moisture (Fertig and Neighbours 1996, p. 16; Heidel 
2009, p. 22). The resultant uneven survival of seedlings may account 
for short-term population fluctuations in this species (Fertig and 
Neighbours 1996, p. 16). Survey results from 1995 may represent peak

[[Page 33948]]

population estimates due to ideal climatic conditions, rather than mean 
or low estimates (Heidel 2009, p. 23). Overall, there is not enough 
information to conclusively determine rangewide trends for the species.

Five Factor Evaluation for Penstemon gibbensii

    Information pertaining to Penstemon gibbensii in relation to the 
five factors provided in section 4(a)(1) of the Act is discussed below.

Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range

    The following potential factors that may affect the habitat or 
range of Penstemon gibbensii are discussed in this section: (1) Energy 
development, (2) roads, (3) trampling, (4) nonnative invasive plants, 
and (5) climate change and drought.
Energy Development
    As previously discussed, many activities associated with energy 
development can destroy or modify habitat. Since 1989, energy 
exploration has increased in the Wyoming portion of the range of 
Penstemon gibbensii (Heidel 2009, p. 28). However, most occurrences of 
P. gibbensii are on unstable slopes that are unlikely to be developed 
for roads, pipelines, or well pads (Fertig and Neighbours 1996, pp. 19-
20; Heidel 2009, p. 28). However, the Sand Creek occurrence, which is 
on flatter terrain, is located in an active oil and gas field, with one 
pipeline passing through a subpopulation of P. gibbensii and an 
accompanying access road intersecting a limited portion (does not 
impact a lot of potential habitat of P. gibbensii) of another 
subpopulation (Heidel 2009, p. 43). A well pad also is located nearby 
(Heidel 2009, p. 28).
    While this development has destroyed some P. gibbensii habitat, 
some of the land disturbances at Sand Creek have provided additional 
habitat by exposing appropriate substrate for plant establishment (Dorn 
1990a, p. 13; Heidel 2009, p. 43). Two pipelines have been laid at the 
Willow Creek occurrence, one adjacent to a subpopulation and the other 
through a subpopulation that may have destroyed plants (Heidel 2009, p. 
55). However, these developments dissect limited areas of occupied 
habitat at Willow Creek, and the current impacts are likely not severe 
as most of P. gibbensii is located on unstable slopes (Heidel 2009, p. 
28). The sale of leases for oil and gas development continues in Carbon 
and Sweetwater Counties in Wyoming (BLM 2010c, pp. 51-63, 75-77, 83). 
Consequently, further energy development is possible within the 
foreseeable future; however, potential impacts from it are unknown.
    In addition to oil and gas development, uranium is mined near the 
Red Creek Rim occurrence (Heidel 2009, p. 28). No impacts to Penstemon 
gibbensii have been documented as a result of uranium mining. Sub-
bituminous coal underlies portions of the range of Penstemon gibbensii; 
however, this coal is not suitable for strip mining (Heidel 2009, p. 
28). Oil shale rock also is present (Heidel 2009, p. 28). Wind energy 
development and gravel quarry development are possible, but have not 
occurred to date (Heidel 2009, p. 28).
    In conclusion, minimal impacts to Penstemon gibbensii were noted 
from oil and gas development, no impacts have been documented from 
uranium mining, and the other types of development are currently only 
speculative. Therefore, we do not consider energy development to be a 
threat to P. gibbensii now or in the foreseeable future.
Roads
    Roads can destroy or modify habitat. Roads also can increase 
access, leading to trampling or the introduction of nonnative invasive 
plants (discussed below). A few roads cross or are adjacent to 
occurrences of Penstemon gibbensii. As mentioned under energy 
development, one access road intersects a limited portion of a 
subpopulation at the Sand Creek occurrence, but also may provide 
additional habitat as P. gibbensii is able to colonize the margins of 
disturbed areas (Heidel 2009, pp. 28, 43). Another road crosses the 
edge of the Willow Creek occurrence (Heidel 2009, p. 43). At the 
Spitzie Draw occurrence, State Route 318 passes within 0.4 km (0.25 
mi), and an access road passes within 200 m (656 ft) (Spackman and 
Anderson 1999, p. 23). State Route 318 also passes within 50 m (164 ft) 
of a portion of the Sterling Place occurrence (CNHP in litt. 2010a, p. 
3). A steep road is adjacent to the Flat Top Mountain occurrence 
(Fertig and Neighbours 1996, p. 35). The Flat Top Mountain road is 
experiencing erosion that, if unchecked, could eventually encroach on 
P. gibbensii occupied habitat (Fertig and Neighbours 1996, p. 35; 
Heidel 2009, p. 59). We have no information on the building of future 
roads, but do not anticipate any based on the topography and isolated 
nature of most of P. gibbensii's distribution. Although some roads 
occur in and near the habitat of P. gibbensii, we do not have any 
indication that they have significant negative effects to the species. 
Additionally, we have no information on dust or levels of travel on 
these roads impacting P. gibbensii or its habitat.
    In conclusion, only minimal impacts to Penstemon gibbensii were 
noted from roads. Therefore, we do not consider roads to be a threat to 
P. gibbensii now or in the foreseeable future.
Trampling
    Trampling by livestock, ORVs, or human foot traffic can destroy 
plants and increase soil erosion, especially at sites with steep, loose 
soils. It has been mentioned as a potential concern at seven of nine 
occurrences (Warren in litt. 1992, unpaginated; Fertig and Neighbours 
1996, p. 20; Spackman and Anderson 1999, p. 31; Fertig 2000d, 
unpaginated; Heidel 2009, p. 28; CNHP in litt. 2010a, p. 4). Penstemon 
gibbensii may colonize the margins of disturbed areas, but cannot 
become established within an area of active use (Heidel 2009, p. 28). 
Soil disturbance has been noted at the Sterling Place occurrence from 
cattle bedding down (CNHP in litt. 2010a, p. 4) and at the Cherokee 
Basin occurrence from humans (Warren in litt. 1992, unpaginated). 
Survey activities at Cherokee Basin in 1988 left distinct footprints 
that were still distinguishable in places 3 years later (Warren in 
litt. 1992, unpaginated).
    As stated above, biological soil crusts have been noted at 
occurrences in Colorado and Utah, but not in Wyoming (Spackman and 
Anderson 1999, pp. 22, 26; Heidel 2009, pp. 14, 20; CNHP 2010a, 
unpaginated; in litt. 2010d, p. 2). The absence of biological soil 
crusts in Wyoming may reflect the effects of trampling from 
historically heavy sheep (Ovis aries) grazing (Heidel 2009, p. 27).
    In summary, trampling is a potential concern at most sites and has 
been documented at two sites. However, we have no information regarding 
whether any Penstemon gibbensii plants were actually trampled. 
Additionally, P. gibbensii is able to colonize the margins of disturbed 
habitats and is able to live in Wyoming where there is no evidence of 
biological crusts in their habitat. We have no information indicating 
that trampling is a threat to the species. Therefore, we do not 
consider trampling to be a threat to P. gibbensii now or in the 
foreseeable future.
Nonnative Invasive Plants
    For general background information on nonnative invasive plants, 
please refer to the first paragraph of ``Nonnative Invasive Plants'' 
under Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range in the Five Factor

[[Page 33949]]

Evaluation for Abronia ammophila section.
    Encroachment of nonnative invasive plants may potentially impact 
Penstemon gibbensii. However, P. gibbensii is typically restricted to 
bare, sparsely vegetated slopes with large areas of exposed soil where 
competition with other plant species, including nonnative invasive 
species, is minimal (Heidel 2009, p. 26). Nonnative invasive plant 
numbers are generally low in, and adjacent to, P. gibbensii 
occurrences, and are most common near roads (Spackman and Anderson 
1999, p. 23; Heidel 2009, p. 29). Alyssum desertorum (desert madwort) 
has been documented at or near Cherokee Basin and Red Creek Rim; Bromus 
tectorum, at or near Cherokee Basin, Red Creek Rim, Sand Creek, 
Sterling Place, and Dagget County; Halogeton glomeratus (halogeton), at 
or near Cherokee Basin, Red Creek Rim, Spitzie Draw, and Sterling 
Place; and Salsola australis (Russian thistle), at or near Spitzie Draw 
and Sterling Place (Heidel 2009, p. 29; CNHP 2010a, p. 2; in litt 
2010d, p. 2). These species have been occasionally noted for at least 
10 years (Spackman and Anderson 1999, pp. 23, 27; Heidel 2009, p. 29; 
CNHP 2010a, unpaginated; CNHP 2010e, unpaginated), but there is no 
evidence of increasing trends regarding their numbers at these sites. 
There is no evidence that any of these nonnative invasive species have 
had a negative impact on P. gibbensii.
    Nonnative invasive plants are present at or near six occurrences of 
Penstemon gibbensii. However, their numbers are generally low, and 
there is no evidence that they are problematic. We have no information 
indicating that nonnative invasive plants are a threat to the species. 
Therefore, we do not consider nonnative invasive plants to be a threat 
to P. gibbensii now or in the foreseeable future.
Climate Change and Drought
    For general background information on climate change, please refer 
to the first paragraphs of ``Climate Change'' under Factor A. The 
Present or Threatened Destruction, Modification, or Curtailment of Its 
Habitat or Range in the Five Factor Evaluation for Abronia ammophila 
section.
    Plant species with restricted ranges that also are climatically 
limited may experience population declines as a result of climate 
change (Schwartz and Brigham 2003, p. 11). Whether Penstemon gibbensii 
would be positively impacted by an increase in barren land due to 
drought that provided potential habitat, or negatively impacted by a 
loss of current marginal habitat, cannot be predicted. Dorn (1990a, p. 
6) noted that P. gibbensii has fewer and smaller flowers than most 
species of Penstemon and hypothesized that this species may have once 
grown under moister conditions and could be in long-term decline due to 
climatic change. However, no additional supporting data were provided. 
He also noted that populations at lower, hotter elevations are more 
pubescent, a possible adaptation to conserve moisture (Dorn 1990a, p. 
6).
    Drought is a natural and common phenomenon within the range of 
Penstemon gibbensii (Dorn 1990a, p. 6). Average annual precipitation 
ranges from approximately 26 cm (10 in.) at Wyoming occurrences to 
about 41 cm (16 in.) at Colorado and Utah occurrences (Heidel 2009, pp. 
19-20). As discussed above, P. gibbensii appears to have minimal 
reproductive success in most years because of dry conditions, but 
responds favorably to late-summer moisture that occurs infrequently 
(Fertig and Neighbours 1996, p. 16; Heidel 2009, p. 22). Penstemon 
gibbensii is a warm-season plant that remains succulent through the 
summer; therefore, it can take advantage of summer thunderstorms after 
other species have stopped growing or completed their life cycle 
(Warren in litt. 1992, unpaginated). Morphological adaptations 
discussed above (pubescent, narrow leaves in hotter climes) also 
indicate that the species is not limited by variations in the regional 
climate to a great degree.
    We believe that Penstemon gibbensii has evolved to adapt to 
recurring drought conditions. Short-term population fluctuations, in 
response to varying climatic conditions from year to year, appear to be 
typical for the species. We have no information indicating that climate 
change or drought is a threat to the species. Therefore, we do not 
consider climate change or drought to be a threat to P. gibbensii now 
or in the foreseeable future.
Summary of Factor A
    Two occurrences (Sand Creek and Willow Creek) have experienced 
minor impacts from energy development. Five occurrences (Sand Creek, 
Willow Creek, Spitzie Draw, Sterling Place, and Flat Top Mountain) have 
roads that are nearby or cross a portion of the occurrence. The Sand 
Creek occurrence, which appears to be experiencing more disturbances 
from energy development and road usage than the other sites, has had an 
increase in P. gibbensii numbers according to survey results despite 
these disturbances. We are not aware of any future energy development 
projects being planned in or near any of the P. gibbensii occurrences. 
Furthermore, the topography at most occurrences does not lend itself to 
energy development or road construction (Fertig and Neighbours 1996, 
pp. 19-20; Heidel 2009, p. 28). Therefore, we do not anticipate 
substantial habitat disturbance in the future. Trampling has been 
documented at two sites, but there is no information indicating that 
plants have been destroyed. Nonnative invasive plants are present at or 
near six occurrences of P. gibbensii. However, nonnative invasive plant 
numbers are generally low, and there is no evidence that they are 
problematic. Climate change and drought could potentially modify 
habitat at all occurrences. However, the species appears to have 
adapted to recurrent drought and variations in climatic conditions. 
Adverse impacts due to habitat destruction, modification, or 
curtailment appear minimal at the present time.
    We conclude that the best scientific and commercial information 
available indicates that Penstemon gibbensii is not in danger of 
extinction or likely to become so within the foreseeable future because 
of the present or threatened destruction, modification, or curtailment 
of its habitat or range.

Factor B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    We are not aware of any adverse impacts to Penstemon gibbensii from 
overutilization for commercial, recreational, scientific, or 
educational purposes at this time. We conclude that the best scientific 
and commercial information available indicates that P. gibbensii is not 
in danger of extinction or likely to become so within the foreseeable 
future because of overutilization for commercial, recreational, 
scientific, or educational purposes.

Factor C. Disease or Predation

Disease
    We are not aware of any adverse impacts to Penstemon gibbensii from 
disease at this time. Therefore, we do not consider disease to be a 
threat to P. gibbensii now or in the foreseeable future.
Predation--Grazing and Herbivory
    Penstemon gibbensii is relatively succulent and may be grazed by 
mule deer (Odocoileus hemionus), pronghorn (Antilocapra americana), 
domestic cattle (Bos taurus), and other herbivores

[[Page 33950]]

during late summer when green vegetation is sparse (Heidel 2009, p. 
26). Currently, there is no sheep grazing in the habitat of P. 
gibbensii (Fertig and Neighbours 1996, p. 19); as discussed above, 
historical sheep use may have been heavy in Wyoming (Heidel 2009, p. 
14). Grazing appears to be restricted almost entirely to flowering 
stems, which could impact seed production, seed bank replenishment, and 
long-term viability (Fertig and Neighbours 1996, p. 19). However, steep 
slopes, unstable footing, and overall low forage production in P. 
gibbensii habitat may limit use by wildlife and livestock (Warren in 
litt. 1992, unpaginated; Heidel 2009, p. 27).
    Grazing intensity often varies between years and between sites and 
does not appear to negatively affect Penstemon gibbensii. At the 
Spitzie Draw occurrence, variable levels of browsing by mule deer were 
noted in 2009 (CNHP in litt. 2009a, unpaginated; in litt. 2009b, 
unpaginated), but little evidence of grazing or browsing was found in 
2010 (CNHP in litt. 2010c, p. 2). At the Sterling Place occurrence, 
there was little evidence of damage to P. gibbensii from mule deer or 
elk (Cervus canadensis), but there was moderate to heavy cattle grazing 
(CNHP in litt. 2010a, p. 2). At the Daggett County occurrence, there 
was little evidence of any grazing (CNHP in litt. 2010b, p. 2). P. 
gibbensii numbers at Flat Top Mountain were high in 1995 and low in 
2008 (see Table 2). However, plants experienced low levels of herbivory 
(approximately 5 percent) in both years (Heidel 2009, p. 24). Cattle 
grazing also was observed at the Sand Creek occurrence in 2005 (Heidel 
2009, p. 43).
    The Cherokee Basin occurrence is the only site that is fenced. In 
1985, the BLM fenced 95 percent of the site to exclude cattle, and 5 
percent or less was left unfenced (Warren in litt. 1992, unpaginated). 
The allotment, an area larger than the P. gibbensii occurrence, was 
monitored to compare the effects of grazing pressure (Warren in litt. 
1992, unpaginated). In 1992, the overall level of livestock use in the 
allotment was low to moderate, the range was in good to excellent 
condition with an improving trend, and a reduced stocking rate was not 
recommended (Warren in litt. 1992, unpaginated). The Cherokee Basin 
exclosure has been critical in ruling out grazing as the cause of 
recent declines at this occurrence, where plant numbers have declined 
since the early 1990s (see Table 1) (Heidel 2009, p. 30).
    No specific information regarding grazing is available for the T84N 
R18W, Willow Creek, or Red Creek Rim occurrences, other than general 
observations regarding the potential for grazing by livestock and 
wildlife.
    Grazing intensity is variable between years and sites, but appears 
to have minimal impact to Penstemon gibbensii, possibly because of 
steep slopes, unstable footing, and overall low forage production in 
the species' habitat. Fluctuations in plant numbers have occurred at 
Flat Top Mountain, despite consistent levels of grazing, and at 
Cherokee Basin, in the absence of grazing, which supports the 
conclusion that grazing causes minimal adverse impacts to P. gibbensii. 
Therefore, we do not consider grazing to be a threat to P. gibbensii 
now or in the foreseeable future.
Summary of Factor C
    We have no evidence of adverse impacts to Penstemon gibbensii from 
disease. P. gibbensii is relatively succulent and may be grazed by both 
wildlife and livestock, particularly in late summer when most sympatric 
vegetation has dried. However, the typical habitat of P. gibbensii 
(steep slopes, loose substrate, and sparse vegetative cover) appears to 
limit heavy grazing at most sites and minimize impacts from grazing.
    We conclude that the best scientific and commercial information 
available indicates that Penstemon gibbensii is not in danger of 
extinction or likely to become so within the foreseeable future because 
of disease or predation.

Factor D. The Inadequacy of Existing Regulatory Mechanisms

    The Act requires us to examine the adequacy of existing regulatory 
mechanisms with respect to threats that may place Penstemon gibbensii 
in danger of extinction or likely to become so in the future. Existing 
regulatory mechanisms that could have an effect on potential threats to 
P. gibbensii include (1) Federal laws and regulations; (2) State laws 
and regulations; and (3) local land use laws, processes, and 
ordinances. Actions adopted by local groups, States, or Federal 
entities that are discretionary, including conservation strategies and 
guidance, are not regulatory mechanisms; however, we may discuss them 
in relation to their effects on potential threats to the species.
Federal Laws and Regulations
Bureau of Land Management
    Most known Penstemon gibbensii occurrences are on BLM land (see 
Table 2). The BLM recognizes P. gibbensii as a sensitive species 
throughout its range (Heidel 2009, p. 6). Sensitive species designation 
requires that the species is: (1) Native, (2) at risk or populations 
trending downward throughout all or a significant portion of its range, 
and (3) dependent on special or unique habitat on BLM lands (Sierra 
2009, in litt.). As discussed above, these species are managed to 
promote their conservation and minimize the likelihood and need for 
listing under the Act. The oldest known occurrence at Cherokee Basin 
was fenced by the BLM for added protection (see Factor C). Four 
occurrences (Cherokee Basin, Flat Top Mountain, Spitzie Draw, and 
Sterling Place) were recommended by the BLM for designation as ACECs 
(Heidel 2009, pp. 30-31). However, the final records of decision for 
the Rawlins RMP in Wyoming and the Little Snake River RMP in Colorado 
did not designate any of these occurrences as ACECs (Heidel 2009, pp. 
30-31). Designation as an ACEC would have protected these sites from 
surface disturbances associated with energy and road development. 
Nevertheless, as discussed under Factor A, additional energy 
development is not anticipated, and the steep slopes found at these 
sites render them ill-suited for most road construction.
National Wildlife Refuge
    Browns Park National Wildlife Refuge maintains a variety of native 
habitats and wildlife, with emphasis on migratory birds, threatened and 
endangered species, and species of special concern. The NWR has a 
portion of one occurrence of Penstemon gibbensii, which is protected by 
refuge regulations that require all vehicles to remain on developed 
roads and prohibit the collection, possession, or destruction of any 
plant (Service 2010, unpaginated).
National Environmental Policy Act
    Most known Penstemon gibbensii (approximately 77 percent) occur on 
Federal and State land (Heidel 2009, pp. 22, 27). All Federal agencies 
are required to adhere to the NEPA for projects they fund, authorize, 
or carry out. Please refer to the NEPA discussion under Factor D. The 
Inadequacy of Existing Regulatory Mechanisms in the Five Factor 
Evaluation for Abronia ammophila section for additional information.
State Regulatory Mechanisms
    The Penstemon gibbensii occurrence in Daggett County, Utah, and a 
portion of the T84N R18W, Wyoming occurrence are on State lands. P. 
gibbensii is designated as a rare plant in Utah and a species of 
concern in Wyoming (WNDD 2007, p. 2; Utah Rare Plants 2010, p. 2). 
These designations

[[Page 33951]]

signify recognition by the States regarding the rarity of the species, 
but do not confer any specific protection.
Local Land Use Laws, Ordinances, and Contracts
The Nature Conservancy
    TNC has a conservation easement on the private land portion of the 
T84N R18W occurrence that protects the area from many development 
activities (Heidel 2009, p. 31). This is a permanent easement that 
includes surface rights, but not mineral rights (Browning 2010, pers. 
comm.).
Summary of Factor D
    We have no evidence of impacts to Penstemon gibbensii from 
inadequate regulatory mechanisms. All but a portion of one occurrence 
are on Federal or State lands. The portion on private land is largely 
protected by a conservation easement. Seven of the nine known 
occurrences are managed all or in part by BLM, which promotes the 
conservation of sensitive species and minimizes the likelihood and need 
for their listing under the Act. The Service has refuge regulations 
that protect P. gibbensii occurring on their lands.
    We conclude that the best scientific and commercial information 
available indicates that Penstemon gibbensii is not in danger of 
extinction or likely to become so within the foreseeable future because 
of inadequate regulatory mechanisms.

Factor E. Other Natural or Manmade Factors Affecting Its Continued 
Existence

    Natural and manmade factors with the potential to affect Penstemon 
gibbensii include: (1) Small population size, (2) pollination, and (3) 
genetic diversity.
Small Population Size
    For general background information on small population size, please 
refer to the first paragraph of ``Small Population Size'' under Factor 
E. Other Natural or Manmade Factors Affecting Its Continued Existence 
in the Five Factor Evaluation for Abronia ammophila section.
    No information exists regarding the historical range or population 
numbers of Penstemon gibbensii, but experts familiar with the species 
conclude that it was likely historically rare (Dorn 1990a, p. 6; Fertig 
and Neighbours 1996, p. 4; Spackman and Anderson 1999, p. 32; Heidel 
2009, p. 5). P. gibbensii is a local endemic that has evolved to 
exploit a barren, erodible habitat (Dorn 1990a, p. 3). The slight 
morphological differences, different substrates, and widely separated 
distribution suggest that the species is a paleoendemic (has been in 
existence for a long period of time in a single region) (Dorn 1990a, p. 
6; Heidel 2009, p. 5). Detailed descriptions of the species' abundance 
and trends are provided under the Abundance and Trends sections for 
this species. No occurrences have been extirpated since the species was 
first identified in 1981, indicating some resilience to perturbation.
    New occurrences of Penstemon gibbensii continue to be documented 
including Willow Creek in 2004 and Red Creek Rim in 2008 (Heidel 2009, 
p. 9). P. gibbensii is presently known from nine occurrences that span 
a distance of 193 km (120 mi) (Heidel 2009, p. 31). Some potentially 
suitable areas have not yet been surveyed (Heidel 2009, pp. 10-12), and 
more occurrences may be located.
    Penstemon gibbensii is likely a historically rare plant that has 
nonetheless persisted. Existing sites are monitored, and surveys have 
located new occurrences. No occurrences have been extirpated. We have 
no information indicating that random demographic or environmental 
events are a threat to the species because of its small population 
size. Therefore, we do not consider small population size to be a 
threat to P. gibbensii now or in the foreseeable future.
Pollination
    Penstemons are pollinated by a variety of insects and hummingbirds, 
but most commonly by insects from the Order Hymenoptera (Wolfe et al. 
2006, pp. 1699, 1709). Bees have been seen visiting flowers at sites in 
Colorado and Utah (Langton 2010, pers. comm.). As discussed above, 
pollinators may regard small populations as inferior or unreliable food 
sources, leading to low visitation rates (Oostermeijer 2003, p. 23). 
Low visitation rates may be more of a concern in currently rare species 
that were historically abundant (Brigham 2003, p. 84). However, as 
identified above, Penstemon gibbensii is believed to have been 
historically rare (Dorn 1990a, p. 6; Fertig and Neighbours 1996, p. 4; 
Spackman and Anderson 1999, p. 32; Heidel 2009, p. 5).
    Only very limited information is available regarding pollination of 
Penstemon gibbensii. However, we have no information indicating that 
poor pollination is a threat to the species. Therefore, we do not 
consider lack of pollinators to be a threat to P. gibbensii now or in 
the foreseeable future.
Genetic Diversity
    For general background information on genetic diversity, please 
refer to the first paragraph of ``Genetic Diversity'' under Factor E. 
Other Natural or Manmade Factors Affecting Its Continued Existence in 
the Five Factor Evaluation for Abronia ammophila section.
    The risk of negative consequences to rare plants from reduced 
genetic diversity varies (Brigham 2003, p. 88). Penstemon gibbensii is 
one of several plant species being studied in a comparative population 
genetics analysis. Initial results from a study of two Wyoming 
populations document high variation of DNA sequences within populations 
examined to date; however, between-population differentiation analysis 
has not yet been conducted (Heidel 2009, p. 5). These results are 
preliminary and limited in scope, but indicate that an adequate level 
of genetic diversity exists in these populations. Genetic exchange 
could be possible as three of the Wyoming occurrences and the three 
occurrences in Colorado and Utah are within 5 to 8 km (3 to 5 mi) of 
each other (Heidel 2009, p. 9).
    Only very limited information regarding the genetic diversity 
exhibited by Penstemon gibbensii is available. However, we have no 
information indicating that a lack of genetic diversity is a threat to 
the species. Therefore, we do not consider reduced genetic diversity to 
be a threat to P. gibbensii now or in the foreseeable future.
Summary of Factor E
    We conclude that the best scientific and commercial information 
available indicates that Penstemon gibbensii is not in danger of 
extinction or likely to become so within the foreseeable future because 
of small population size, reduced pollination, or reduced genetic 
diversity.

Finding

    As required by the Act, we considered the five factors in assessing 
whether Penstemon gibbensii is threatened or endangered throughout all 
of its range. We examined the best scientific and commercial 
information available regarding the past, present, and future threats 
faced by the species. We reviewed the petition, information available 
in our files, other available published and unpublished information, 
and we consulted other Federal and State agencies.
    Five occurrences (Sand Creek, Willow Creek, Spitzie Draw, Sterling 
Place, and

[[Page 33952]]

Flat Top Mountain) have experienced some minimal adverse impacts to the 
habitat of Penstemon gibbensii due to oil and gas development and road 
construction. The topography at most occurrences does not lend itself 
to energy development or road construction; therefore, we do not 
anticipate substantial habitat disturbance in the future. All 
occurrences could experience increased temperatures and precipitation 
changes from climate change. Whether this would result in a net gain or 
net loss in potential habitat cannot be predicted. However, differing 
morphological adaptations at the various occurrences indicate that the 
species can adapt to variable climate conditions.
    Five occurrences (Sand Creek, Flat Top Mountain, Spitzie Draw, 
Sterling Place, and Daggett County) have documentation of grazing. 
However, the typical habitat of P. gibbensii (steep slopes, loose 
substrate, and sparse vegetative cover) appears to limit heavy grazing. 
Two occurrences (Cherokee Basin and Sterling Place) have experienced 
some trampling by humans and livestock. However, we are not aware of 
any loss of P. gibbensii at either of these sites from trampling.
    All occurrences experience drought as a natural and regular 
phenomenon, which likely results in short-term population fluctuations. 
However, P. gibbensii has evolved to adapt to recurring drought 
conditions. Six occurrences (Cherokee Basin, Sand Creek, Red Creek Rim, 
Spitzie Draw, Sterling Place, and Daggett County) have nonnative 
invasive plants at or near the site. However, the typical habitat of P. 
gibbensii is sparsely vegetated slopes with large areas of bare soil 
where competition with other plant species, including nonnative 
invasive plants, is minimal.
    All occurrences have relatively small populations. However, P. 
gibbensii is considered historically rare. No occurrences have been 
extirpated since the species was first identified, and new occurrences 
continue to be documented. We have no information regarding actual or 
potential adverse impacts due to overutilization, disease, inadequate 
regulatory mechanisms, reduced genetic diversity, or reduced 
pollination.
    Based on our review of the best available scientific and commercial 
information pertaining to the five factors, we find that the threats 
are not of sufficient imminence, intensity, or magnitude to indicate 
that Penstemon gibbensii is in danger of extinction (endangered), or 
likely to become endangered within the foreseeable future (threatened), 
throughout all of its range. Therefore, we find that listing P. 
gibbensii as a threatened or endangered species is not warranted 
throughout all of its range.

Significant Portion of the Range

    Having determined that Penstemon gibbensii does not meet the 
definition of a threatened or endangered species, we must next consider 
whether there are any significant portions of the range where P. 
gibbensii is in danger of extinction or is likely to become endangered 
in the foreseeable future.
    In determining whether Penstemon gibbensii is threatened or 
endangered in a significant portion of its range, we first addressed 
whether any portions of the range of P. gibbensii warrant further 
consideration. We evaluated the current range of P. gibbensii to 
determine if there is any apparent geographic concentration of the 
primary stressors potentially affecting the species including energy 
development, roads, climate change, grazing, trampling, drought, 
nonnative invasive plants, and small population size. P. gibbensii is 
likely a historically rare endemic plant known from nine occurrences 
spanning a distance of 193 km (120 mi) (Heidel 2009, p. 31). This 
species' small range suggests that stressors are likely to affect it in 
a uniform manner throughout its range. All stressors occur at or near 
most sites, with the exception of energy development, which has been 
documented at or near three occurrences. However, the sale of oil and 
gas leases is ongoing; consequently, it is a potential stressor at most 
sites. Effects to P. gibbensii from these stressors are not 
disproportionate in any portion of the species' range. As we explained 
in detail in our analysis of the status of the species, none of the 
stressors faced by the species are sufficient to place it in danger of 
extinction now (endangered) or in the foreseeable future (threatened). 
Therefore, no portion is likely to warrant further consideration, and a 
determination of significance is not necessary.
    We do not find that Penstemon gibbensii is in danger of extinction 
now, nor is it likely to become endangered within the foreseeable 
future throughout all or a significant portion of its range. Therefore, 
listing P. gibbensii as threatened or endangered under the Act is not 
warranted at this time.
    We request that you submit any new information concerning the 
status of, or threats to, Penstemon gibbensii to our Wyoming Ecological 
Services Field Office (see ADDRESSES section) whenever it becomes 
available. New information will help us monitor P. gibbensii and 
encourage its conservation. If an emergency situation develops for P. 
gibbensii, or any other species, we will act to provide immediate 
protection.

Species Information for Boechera pusilla

Species Description

    Boechera pusilla (Fremont County rockcress or small rockcress) is a 
perennial herb with several decumbent (lying down), unusually slender 
stems up to 17 cm (6.7 in.) long. The plant has basal leaves that are 
linear (at least 10 times longer than wide) and erect, with relatively 
sparse forked spreading hairs located on the leaves. Plants generally 
have three to five stem leaves that are nonclasping (not encircling the 
stem) and widely spaced. Flowers are small, light lavender, four-
petaled, and blossom from May to mid-June. The fruits, which are 
present from mid-June to July, are hairless linear siliques (narrow 
elongated seed capsule) that spread at right angles from the drooping 
main stem on pedicels (small stalks) less than 3 mm (0.12 in.) 
(Marriott 1986, p. 3; Dorn 1990b, pp. 2-3; Fertig 1994, unpaginated; 
Heidel 2005, p. 3).

Discovery and Taxonomy

    Boechera pusilla was first collected near South Pass in Fremont 
County, Wyoming, in 1981 (Dorn 1990b, p. 1). B. pusilla is a member of 
the Brassicaceae (mustard) family and was formerly classified as Arabis 
pusilla (Fertig 1994, unpaginated), which was the name used in the 
petition (Forest Guardians 2007, p. 23). However, studies in 2003 
suggest that most North American Arabis species should be placed in the 
Boechera genus (Al-Shehbaz 2003, entire). This determination was based 
on their distinct chromosome numbers and on molecular data indicating 
that American and Eurasian species that were classified as Arabis have 
more dissimilarities between them than they do with many other widely 
recognized genera in the mustard family (Al-Shehbaz 2003, pp. 382-383). 
Although some botanists do not fully support the change (Murray and 
Elven 2009, unpaginated), reclassification to the Boechera genus has 
been widely accepted (Holmgren et al. 2005, p. 537; Flora of North 
America 2010b, unpaginated). For the purposes of this finding, we 
primarily refer to the species as Boechera pusilla, but consider Arabis 
pusilla to be the same species.
    Boechera pusilla is genetically closely related to Boechera demissa 
var. languida (nodding rockcress), Boechera

[[Page 33953]]

pendulina var. russeola (Daggett rockcress), and Boechera oxylobula 
(Glenwood Springs rockcress) and occurs in a similar geographic area as 
B. demissa var. languida and B. pendulina var. russeola (Dorn 1990b, p. 
5; Heidel 2005, p. 2). Five additional species of rockcress occur in or 
near B. pusilla habitat, representing a high amount of diversity within 
the genus (Heidel 2005, p. 2). B. pusilla requires a highly specialized 
habitat (discussed below under Habitat) that is newly formed, which 
suggests the species is relatively recently derived from a common 
ancestor (Dorn 1990b, p. 5). Based on morphological evidence, B. 
pusilla may be a hybrid of B. pendulina and B. lemmonii (Lemmon's 
rockcress) (Flora of North America 2010b, unpaginated). We recognize B. 
pusilla as a valid species and a listable entity.

Biology and Life History

    Due to the short growing season (approximately 30 days) in the 
areas that Boechera pusilla occupies, the plant only flowers in May and 
June with fruits maturing several weeks later (Dorn 1990b, p. 9; Fertig 
1994, unpaginated; Heidel 2005, pp. 3, 15). Fruits are only evident 
during the short frost-free period during the middle of summer 
(primarily July) and shatter thereafter (Heidel 2005, p. 15). Remnant 
flower stalks persist through the winter and into the next flowering 
season (Heidel 2005, p. 15).
    Not all plants produce fruit in a particular year (Heidel 2005, pp. 
15-16), which is thought to be caused by freezing conditions in spring 
or possibly drought (Heidel 2005, pp. 15-16). All Boechera pusilla 
reproduction is apparently by seed (Dorn 1990b, p. 9; Heidel 2005, p. 
15), and the species is apomictic (i.e., reproduces by seed with no 
fertilization, resulting in offspring that are essentially clones) 
(Flora of North America 2010b, unpaginated). However, similar Boechera 
species have variation in the amount of sexual and asexual reproduction 
(Roy 1995, pp. 874-876), and we are unsure whether B. pusilla exhibits 
a mixed-mating system. We do not have information about how long the 
species' seeds remain viable or under what conditions they germinate. 
Apomictic species within the Boechera genus result from hybridization 
of sexual Boechera species (Flora of North America 2010b, unpaginated). 
Reproduction of B. pusilla is by (nonwinged) seeds that likely drop 
near the parent plant, with some seeds dispersed via wind or water 
(Dorn 1990b, p. 9). It has relatively few seeds per fruit compared to 
some other Boechera species (Dorn 1990b, p. 9). Dispersal vector 
information is unknown at this time (Heidel 2005, p. 15).

Habitat

    Boechera pusilla occupies sparsely vegetated, coarse granite soil 
pockets in exposed granite-pegmatite outcrops, with slopes generally 
less than 10 degrees, at an elevation between 2,438 to 2,469 m (8,000 
to 8,100 ft) (Dorn 1990b, pp. 3, 6). A pegmatite is a very coarse-
grained igneous (formed from magma or lava) rock that usually occurs in 
dikes (sheet-like body of magma) (Heidel 2005, p. 8). The soils are 
sandy to loamy (mixture of clay, silt and sand), poorly developed, very 
shallow, and possibly subirrigated by runoff from the adjacent exposed 
bedrock (solid consolidated rock) (Dorn 1990b, pp. 6-8). B. pusilla is 
likely restricted in distribution by the limited occurrence of 
pegmatite in the area (Heidel 2005, p. 8). A distribution model shows 
potential habitat could occur in an area no greater than two townships 
(186.5 km\2\; 72 mi\2\) (Heidel 2005, p. 7). The dense nature of 
pegmatite does not allow for fertile soil, therefore restricting 
vegetation growth (Heidel 2005, p. 15). The specialized habitat 
requirements of B. pusilla have allowed the plant to persist without 
competition from other herbaceous plants or sagebrush-grassland species 
that are present in the surrounding landscape (Dorn 1990b, pp. 6, 8).
    Although the surrounding vegetation is sparse (less than 10 percent 
cover), Boechera pusilla is associated with numerous mat-forming 
perennial herbs (e.g., Erigeron caespitosus (tufted fleabane)), 
perennial grasses (e.g., Achnatherum hymenoides (Indian ricegrass)), 
and shrubs (e.g., Artemesia arbuscula (dwarf sagebrush)) (Heidel 2005, 
p. 9). Rolling hills with a gradual sloping impediment are the 
predominant landscape features in the area, which is a transition zone 
between the montane conifer forests and the high sagebrush desert 
(Heidel 2005, pp. 8-9). The adjacent vegetation consists primarily of 
sagebrush-grassland or open Pinus flexilis (limber pine) habitat (Dorn 
1990b, p. 8).
    Annual precipitation in the area averages 30.5 cm (12 in.), with 
the majority falling in the form of winter snow (Marriott 1986, p. 9). 
Average minimum and maximum temperatures in this area range between -
16.1 and -3.9 [deg]C (3 and 25 [deg]F) in January and 4.6 and 24.4 
[deg]C (42 and 76 [deg]F) in July (Dorn 1990b, p. 6), with strong, 
frequent winds present year-round (Heidel 2005, p. 10). This area has a 
very short growing season; approximately 30 frost-free days occur 
between mid-June and mid-July (Marriott 1986, p. 9). Boechera pusilla 
may be adapted to wide fluctuations in available moisture as the soil 
goes through cycles of rapid drying and saturation (Dorn 1990b, p. 6).

Distribution and Abundance

    The distribution of Boechera pusilla is extremely limited due to 
its very specific habitat requirements (Dorn 1990b, p. 8). The only 
known population of B. pusilla is located on lands administered by the 
BLM Rock Springs Field Office in the southern foothills of the Wind 
River Range (Fertig 2000a, p. 39; Heidel 2005, pp. ii, 6). The species' 
range is approximately 64.8 ha (160 ac), with occupied habitat 
estimates ranging from 2.4 to 6.5 ha (6 to 16 ac) (Dorn 1990b, p. 8; 
Heidel 2005, p. 15). Botanists have surveyed for B. pusilla 
systematically in other areas and discovered no additional populations, 
but some areas with potential habitat have not been surveyed (Marriott 
1986, p. 8; Heidel 2005, p. 6).
    To explain the trend of Boechera pusilla numbers, we use the 
estimates of total flowering plants in the entire population (i.e., 
total for the species) and the total flowering plants in a plot located 
in the largest subpopulation. These two indicators are the most 
consistently documented information we could find. The number of 
flowering plants is used, at least in part, to ensure identification of 
the species (Heidel 2010d, pers. comm.). In 1988, the total population 
estimate was 800 to 1,000 flowering individuals (Heidel 2005, p. 14). 
This was an increase from the 50 plants found in 1986; however, only 1 
subpopulation was discovered that year (Marriott 1986, p. 15). In 1990, 
numbers were down to about 600 flowering plants for the entire 
population (Dorn 1990b, p. 8). Although the 1988 survey indicated no 
evidence that B. pusilla was affected by the 1988 drought (Marriott and 
Horning in litt. 1988, p. B2), drought impacts, such as reduced seed 
fecundity or germination, may not be immediately apparent (Heidel 
2010c, pers. comm.; 2010d, pers. comm.). The decrease to 600 flowering 
plants documented in 1990 may be due to a pattern of short-term decline 
under drought conditions that occurred in this area between 1988 and 
1990 (Heidel 2005, p. 14).
    In 2003, WYNDD estimated total flowering plants for the entire 
population at 150 to 250 (Heidel 2005, p. 14). The mean density of 
flowering plants derived from the 1988 and 2003 surveys indicate that 
the density dropped from 1.68 down to 0.33 flowering plants per m\2\ 
(0.156 down to 0.031 flowering plants per ft\2\) during

[[Page 33954]]

this 15-year period (Heidel 2005, p. 14). Declines in 2003 may be 
attributed to severe drought conditions recorded in the Wind River 
Range between 2000 and 2003 (NOAA 2005 as cited in Heidel 2005, p. 14). 
Flowering plants for the entire population in 2010 were estimated at 
approximately 350 individuals (Heidel 2010d, pers. comm.).
    The subpopulation plot, where the largest number of plants is 
found, had 671 individual flowering Boechera pusilla plants in 1988 
(Heidel 2005, p. 14). This area had 87 flowering plants when it was 
counted again in 2003 (Heidel 2005, p. 14). In 2010, the plot had 56 
flowering plants (Heidel 2010c, pers. comm.). Flowering plant numbers 
in the subpopulation plot has consistently declined. However, numbers 
of flowering plants for the entire subpopulation where the plot is 
located increased from between 100 and 150 in 2003 (Heidel 2005, p. 14) 
to 283 in 2010 (Heidel 2010c, pers. comm.). The decrease of plants in 
the plot but increase in the subpopulation over this period suggests 
the distribution of the subpopulation shifted over that period of time 
(Heidel 2010c, pers. comm.).
    Boechera pusilla has at least eight subpopulations (Amidon 1994, in 
litt., unpaginated), the largest of which has been surveyed 
periodically as described above (Heidel 2005, p. 14; Heidel 2010c, 
pers. comm.). Additional subpopulations are small; in 2003, 1 
subpopulation had 30 to 50 flowering plants, another had 10 to 15 
flowering plants, and 5 of the subpopulations had less than 5 flowering 
plants each (Heidel 2005, p. 14).
    Based on a limited number of surveys, the plant appears to have an 
overall pattern of decline documented since estimates were first 
provided in 1988 (Heidel 2005, p. 17; Heidel 2010c, pers. comm.; 
Windham 2010, pers. comm.). Boechera pusilla numbers increased in 2010 
compared to 2003, but the overall trend is downward, with 2010 
population numbers at 350 compared to 800 to 1000 in 1988.
    Reproductive success may vary considerably from year to year 
depending on climate conditions, leading to wide fluctuations in 
populations (Dorn 1990b, p. 10). Possible evidence of these 
fluctuations is low levels of fruit production in 2003 that visibly 
increased in 2010 (Heidel 2010c, pers. comm.). However, 2010 plant 
numbers are low compared to those documented in 1988 and 1990.

Five Factor Evaluation for Boechera pusilla

    Information pertaining to Boechera pusilla in relation to the five 
factors provided in section 4(a)(1) of the Act is discussed below.

Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range

    The following potential factors that may affect the habitat or 
range of Boechera pusilla are discussed in this section: (1) 
Recreational activities, (2) energy development, (3) nonnative invasive 
plants, (4) climate change, and (5) drought.
Recreational Activities
    Boechera pusilla's current known range is highly restricted. All 
known occurrences are on BLM land, which is public land managed for 
multiple use (Dorn, 1990, p. 10; Heidel 2005, p. 6). Prior to the 
development of a Habitat Management Plan (BLM 1994, entire) and the 
closure of vehicle access in 1994 (59 FR 37258), B. pusilla was more 
readily exposed to recreation activity from ORV use associated with 
fishing and camping, unauthorized ORV use, horse boarding and feeding, 
plant collecting, mountain biking and pedestrian use. In addition, a 
nearby quarry, that is now inactive, may have destroyed potential 
habitat (Dorn 1990b, p. 11; Heidel 2005, p. 17). Previously, ORV use 
has been identified as a potential threat; however, conservation 
measures, such as the habitat management plan, have been implemented to 
eliminate this threat. Currently, the only access to the area occupied 
by B. pusilla is by foot, but due to the rocky substrate associated 
with the habitat, recreational use in the area primarily occurs on 
adjacent riparian areas, away from occupied habitat (Dana 2010a, pers. 
comm.). Therefore, recreational activities are not considered a threat 
now or in the foreseeable future.
Energy Development
    The extraction of natural gas occurs in several developments in 
southwest Wyoming, which could be a potential threat to the habitat of 
Boechera pusilla (USGS 2010, p. 3). However, the area occupied by B. 
pusilla is incorporated into a Special Recreation Management Area 
(SRMA), which is closed to mineral and energy development (BLM 1997, 
pp. 17-18). Currently the nearest gas development occurs approximately 
10.1 km (6.3 mi) from the location of B. pusilla (Kile 2010, pers. 
comm.) and does not appear to be a threat to the plant.
    In addition, on February 23, 1998, the Secretary of the Interior 
issued Public Land Order No. 7312, the Withdrawal of Public Land for 
the Protection of Arabis Pusilla Plant Habitat. This order pursuant to 
Section 204 of the Federal Land Policy and Management Act of 1976, 43 
U.S.C. 1714 (1994), withdrew from ``settlement, sale, location, or 
entry under the general land laws, including the United States mining 
laws (30 U.S.C. Ch. 2 (1994)), but not from leasing under the mineral 
leasing laws'' on 412.8 ha (1,020 ac) to protect Boechera pusilla 
habitat (63 FR 9012). This withdrawal expires in 50 years (2048) unless 
the Secretary determines that the withdrawal shall be extended. 
Therefore, we do not consider energy development to be a threat to B. 
pusilla now or in the foreseeable future.
Nonnative Invasive Plants
    For general background information on nonnative invasive plants, 
please refer to the first paragraph of ``Nonnative Invasive Plants'' 
under Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range in the Five Factor Evaluation for 
Abronia ammophila section.
    The habitat adjacent to the area occupied by Boechera pusilla is 
primarily sagebrush steppe, which is highly vulnerable to nonnative 
invasive species (Anderson and Inouye 2001, pp. 531-532); however, 
surveys conducted by WNDD in 2003 found the area generally free of 
nonnative invasive species (Heidel 2005, p. 10). As noted previously, 
the restrictive habitat occupied by B. pusilla may limit the potential 
for competition from other herbaceous plants (Dorn 1990b, pp. 6, 8). We 
have no information that nonnative invasive plants are a threat to B. 
pusilla. Therefore, we do not consider nonnative invasive plants to be 
a threat to B. pusilla now or in the foreseeable future.
Climate Change
    For general background information on climate change, please refer 
to the first paragraphs of ``Climate Change'' under Factor A. The 
Present or Threatened Destruction, Modification, or Curtailment of Its 
Habitat or Range in the Five Factor Evaluation for Abronia ammophila 
section.
    Plant species with restricted ranges may experience population 
declines as a result of climate change. The habitat for Boechera 
pusilla appears to be exposed to variation in moisture, and B. pusilla 
may be adapted to some variation in moisture availability (Dorn 1990b, 
p. 6). Climate change has the

[[Page 33955]]

potential to affect the species' habitat, but we lack scientific 
information on what those changes may ultimately mean for B. pusilla. 
Climate change may affect the timing and amount of precipitation as 
well as other factors linked to habitat conditions for this species. 
However, at this time the available scientific information does not 
indicate that climate change is likely to threaten the species. 
Therefore, we do not consider climate change to be a threat to B. 
pusilla now or in the foreseeable future.
Drought
    Limited evidence shows there may be some response of Boechera 
pusilla to drought conditions, but those effects may be delayed (Heidel 
2010c, pers. comm.). As discussed above, a 1988 survey, conducted 
during a drought year, found increased abundance of plants from 1986 
(Marriott and Horning in litt. 1988, p. B2), but surveys conducted in 
1990 found reduced numbers (Dorn 1990b, p. 8) that may have been caused 
by continued drought conditions (Heidel 2005, p. 14). Reproductive 
success may vary considerably from year to year depending on climate 
conditions, leading to wide fluctuations in populations (Dorn 1990b, p. 
10). Overall reductions in population size since 1988 may be linked to 
periods of drought conditions that have occurred between 1988 and 2010, 
but B. pusilla monitoring efforts are not sufficient during this period 
to understand the role of drought in population decline. Therefore, 
because of lack of evidence, we do not consider drought to be a threat 
to B. pusilla now or in the foreseeable future.
Summary of Factor A
    In summary, we found that numerous management actions taken 
previously by the BLM alleviated several potential threats to Boechera 
pusilla and its habitat. These potential threats included ORV use, 
heavy foot traffic, and mining. The ORV use and mining are no longer 
permitted in the area due to the implementation of numerous regulatory 
mechanisms (see Factor D. Inadequacy of existing regulatory mechanisms 
below) in addition to the construction of an exclosure. We have no 
information that nonnative invasive plants are a threat to the species. 
Other activities in the area, such as limited foot traffic, are not 
considered threats. Although climate change may be a potential long-
term stressor to B. pusilla, the limited information available 
regarding climate change impacts on B. pusilla and the species' 
adaptations to an already-variable climate do not suggest that climate 
change currently, or in the foreseeable future, will threaten this 
species' existence. We do not fully understand the response of B. 
pusilla to drought conditions, but limited evidence indicates that 
drought may be contributing to this species' reduced population size 
(see Factor E. Other Natural Or Manmade Factors Affecting Its Continued 
Existence discussion below). However, we do not have sufficient 
information to say that drought alone, or in combination with other 
factors, threatens the species currently or is likely to do so in the 
foreseeable future.
    We conclude that the best scientific and commercial information 
available indicates that Boechera pusilla is not in danger of 
extinction or likely to become so within the foreseeable future because 
of the present or threatened destruction, modification, or curtailment 
of its habitat or range.

Factor B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    Field notes from 1993 suggest that some Boechera pusilla seed had 
been collected and sent to the DBG; however, they do not have a record 
of receiving any B. pusilla seeds (Neale 2010b, pers. comm.). Some 
specimens collected in the 1980s were provided to the Gray Herbarium of 
Harvard University, the New York Botanical Garden, and the Rocky 
Mountain Herbarium at the University of Wyoming (Dorn 1990b, p. 5, 14). 
We have no other indication that any collections or utilization have 
been made of B. pusilla. Therefore, we find that B. pusilla is not in 
danger of extinction or likely to become so within the foreseeable 
future because of overutilization for commercial, recreational, 
scientific, or educational purposes.

Factor C. Disease or Predation

Disease
    Boechera pusilla is not specifically known to be affected or 
threatened by any disease. Systemic rust disease is known to affect 
many Boechera species (Ladyman 2005, p. 26), but we have no information 
that it is found in B. pusilla. Therefore, we do not consider disease 
to be a threat to B. pusilla now or in the foreseeable future.
Predation--Grazing and Herbivory
    Prior to conservation measures taken by the BLM, the habitat of 
Boechera pusilla was grazed by cattle. Prior to 1982, cattle grazing 
may have formed a threat, but the establishment of an ACEC that covers 
all known locations of B. pusilla (BLM 1997, p. 34) and the presence of 
an exclosure fence that encloses all of the occupied habitat (Dunder 
1984, unpaginated; Marriott 1986, p. 14) have resolved this potential 
threat. These protections are described in additional detail under 
Factor D. Inadequacy of Existing Regulatory Mechanisms below. Insects, 
such as caterpillars, do not appear to favor B. pusilla over other 
vegetation (Heidel 2005, p. 10), and no known observations suggest that 
herbivory from wild ungulates or small mammals is a threat. Therefore, 
we do not consider predation to be a threat to B. pusilla now or in the 
foreseeable future.
Summary of Factor C
    We do not have any information to suggest that disease or predation 
are a threat to this species. We conclude that the best scientific and 
commercial information available indicates that Boechera pusilla is not 
in danger of extinction or likely to become so within the foreseeable 
future because of disease or predation.

Factor D. Inadequacy of Existing Regulatory Mechanisms

    The Act requires us to examine the adequacy of existing regulatory 
mechanisms with respect to threats that may place Boechera pusilla in 
danger of extinction or likely to become so in the future. Existing 
regulatory mechanisms that could have an effect on potential threats to 
B. pusilla include (1) Federal laws and regulations; (2) State laws and 
regulations; and (3) local land use laws, processes, and ordinances. 
Because the entire population of Boechera pusilla occurs on BLM lands, 
we focus our discussion on Federal laws. Actions adopted by local 
groups, States, or Federal entities that are discretionary, including 
conservation strategies and guidance, are not regulatory mechanisms; 
however, we may discuss them in relation to their effects on potential 
threats to the species.
Federal Laws and Regulations
Bureau of Land Management
    Several regulatory mechanisms are in place to protect Boechera 
pusilla, some of which were mentioned under Factor A. The Present or 
Threatened Destruction, Modification, or Curtailment of Its Habitat or 
Range above. The BLM has excluded grazing from the habitat area, 
developed a habitat management plan for the species, designated the 
habitat area as an ACEC, incorporated the habitat area into a SRMA, and 
designated B. pusilla as a sensitive species. Additionally, the

[[Page 33956]]

Secretary of the Interior removed essentially the entire area with 
occupied habitat from mineral development. The Service previously 
published a notice of review in 2000 removing B. pusilla as a candidate 
species, largely based on protections provided by these regulatory 
mechanisms and land management approaches.
    The BLM designated the Pine Creek Special Management Area in 1978 
(Heidel 2005, p. 16) and built an exclosure fence in 1982 to keep 
cattle out of the 35.6-ha (88-ac) area where recreational activities 
occur (Dunder 1984, unpaginated). Boechera pusilla occurs within this 
management area (Marriott 1986, p. 14). The fenced portion of the area 
is smaller than that of the known species range, but protects much of 
the occupied habitat. As described under Factor A. The Present or 
Threatened Destruction, Modification, or Curtailment of Its Habitat or 
Range above, the BLM provided a Habitat Management Plan for B. pusilla 
(BLM 1994, entire) and processed an emergency closure of vehicle access 
to 202.3 ha (500 ac) in a Habitat Management Area for the species in 
1994 (59 FR 17718).
    The BLM 6840 Manual requires that RMPs should address sensitive 
species, and that implementation ``should consider all site-specific 
methods and procedures needed to bring species and their habitats to 
the condition under which management under the Bureau sensitive species 
policies would no longer be necessary'' (BLM 2008, p. 2A1). The Federal 
Land Policy and Management Act of 1976 mandates Federal land managers 
to develop and revise land use plans. The RMPs are the basis for all 
actions and authorizations involving BLM-administered lands and 
resources (43 CFR 1601.0-5(n)). The 1997 RMP for the area that includes 
Boechera pusilla habitat provided designation of a Special Status Plant 
ACEC that closed the area to: (1) Direct surface-disturbing activities, 
(2) mining claims, (3) surface occupancy and surface-disturbance 
activities, (4) mineral material sales, and (5) use of explosives and 
blasting (BLM 1997, p. 34). B. pusilla habitat also fits within an SRMA 
designated in the RMP, which: (1) Prohibited major facilities (e.g., 
power lines), (2) closed the area to mineral leasing, (3) closed the 
ACEC to ORV use, and (4) required avoidance and extensive planning of 
long, linear facilities (e.g., roads) (BLM 1997, pp 17-18). All 
activities concerning B. pusilla in the RMP have been implemented 
(Glennon 2010b, pers. comm.). The next RMP revision for the area is 
currently underway, with an estimated completion date of 2013 (Dana 
2010b, pers. comm.). Existing protections for the species will likely 
remain in place in the revised RMP as a no-action alternative under 
NEPA, but we are uncertain whether additional protections for B. 
pusilla will be developed.
National Environmental Policy Act
    The entire known population of Boechera pusilla occurs on Federal 
land. All Federal agencies are required to adhere to the NEPA for 
projects they fund, authorize, or carry out. Please refer to the NEPA 
discussion under Factor D. The Inadequacy of Existing Regulatory 
Mechanisms in the Five Factor Evaluation for Abronia ammophila section 
for additional information.
Public Land Order No. 7312
    On February 23, 1998, the Secretary of the Interior issued Public 
Land Order No. 7312 to withdraw public land from certain uses for 50 
years as a measure to protect Boechera pusilla. This order withdrew 
412.8 ha (1,020 ac) from settlement, sale, location of minerals, or 
entry under the general land laws, including mining laws; this did not 
eliminate the area from being leased under the mineral leasing laws (63 
FR 9012). In addition to these measures, B. pusilla was listed as a BLM 
sensitive species in 2002 (BLM 2002, p. 9).
Summary of Factor D
    Because the entire population of Boechera pusilla occurs on BLM 
lands, this agency has responsibility for the land management decisions 
that protect B. pusilla and its habitat. B. pusilla receives adequate 
protection from the BLM in the form of regulatory mechanisms, 
designations, and the construction of animal exclosures. These 
protections greatly limit the amount of disturbance that can occur 
within the plant's limited range. Although these mechanisms do not 
entirely exclude the area from foot traffic, they have adequately 
reduced this potential threat. Various regulatory mechanisms are in 
place to address potential threats over which the BLM has control. We 
expect that B. pusilla and its habitat will be generally protected from 
direct human disturbance.
    We have no evidence of impacts to Boechera pusilla from inadequate 
regulatory mechanisms. We recognize that the existing regulatory 
mechanisms have not been able to stem the decline of the species, but 
we are not able to identify that regulatory mechanisms are inadequate. 
We are uncertain what is causing reduced population levels and consider 
the reduction to be an indicator that a threat is present; however, we 
are not able to fully describe this threat at this time (see Factor E. 
Other Natural Or Manmade Factors Affecting Its Continued Existence 
discussion below). The current small population size creates a 
vulnerability that may work in combination with the threat that we are 
not able to explain. Since the primary management tool that implements 
regulatory mechanisms, the RMP, goes through revisions approximately 
every 15 years (Dana 2010b, pers. comm.), it will be important for the 
BLM to ensure that the protective measures are sustained in future 
revisions to the Green River RMP and that measures be taken to 
alleviate any potential vulnerabilities created by small population 
size.
    We conclude that the best scientific and commercial information 
available indicates that Boechera pusilla is not in danger of 
extinction or likely to become so within the foreseeable future because 
of inadequate regulatory mechanisms. We recognize that the existing 
regulatory mechanisms do not appear to have protected the species from 
decline; however, we are unable to conclude that regulatory mechanisms 
are inadequate since the cause for decline is unidentified.

Factor E. Other Natural or Manmade Factors Affecting Its Continued 
Existence

    Natural and manmade factors with the potential to affect Boechera 
pusilla include: (1) Small population size, and (2) threats not yet 
fully identified.
Small Population Size
    For general background information on small population size, please 
refer to the first paragraph of ``Small Population Size'' under Factor 
E. Other Natural or Manmade Factors Affecting Its Continued Existence 
in the Five Factor Evaluation for Abronia ammophila section.
    In order for a population to sustain itself, there must be enough 
reproducing individuals and habitat to ensure its survival. 
Conservation biology defines this as the ``minimum viable population'' 
requirement (Grumbine 1990, pp. 127-128). This requirement may be 
between 500 and 5,000 individuals for other species of Boechera 
depending on variability among species, demographic constraints, and 
evolutionary history (Ladyman 2005, p. 26). Boechera pusilla occurs in 
relatively small numbers, with the total population size no greater 
than

[[Page 33957]]

1,000 flowering plants in the past (Heidel 2005, p. 14) and at 350 
flowering plants in 2010 (Heidel 2010d, pers. comm.). Plant numbers are 
at levels that may not ensure this species' continued existence over 
the long term. As noted above, botanists who have studied B. pusilla 
note an overall declining trend of the species (Heidel 2005, p. 14; 
Heidel 2010c, pers. comm.; Windham 2010, pers. comm.). This decline has 
been rapid compared to declines observed in other rare species and has 
continued after habitat protections were put in place (Windham 2010, 
pers. comm.). As established in an earlier section, the number of 
flowering plants in the population in 2010 was approximately 350, an 
increase from 2003 estimates of 150 to 250. However, if a decline 
similar to the significant decrease between 1988 (800 to 1,000 
flowering plants) and 2003 (150 to 250 flowering plants) occurs again, 
the species may have difficulty perpetuating itself into the future.
    Boechera pusilla relies on soils formed from a certain type of 
granitic outcrop that is limited in extent, so the range of the species 
is not likely to expand beyond this area in the future. The relatively 
small area that B. pusilla occurs within also may predispose the 
species to be more sensitive to stochastic events that might occur 
(Menges 1990, p. 53; Boyce 1992, pp. 482-484), such as climate shift 
that the species is not adapted to or factors that lead to reduced 
reproductive success (Ladyman 2005, pp. 30-31). A single unforeseen 
event in a relatively small area could eliminate the species.
    Boechera pusilla is apomictic, so when it uses this reproductive 
process, the species essentially clones itself. We are uncertain how 
long the species' apomictic seeds remain viable or under what 
conditions they germinate. This reproductive process may reduce some of 
the risks associated with small population size for species that only 
sexually reproduce. If the species reproduces only asexually, risks 
related to lack of genetic variability may increase, but we are 
uncertain if B. pusilla also reproduces sexually as do some other 
species of Boechera. Apomixis has been shown to reduce extinction risk 
if certain other variables are present, such as high levels of biomass 
and no soil acidity (Freville et al. 2007, p. 2666). However, 
information on what apomixis means for conservation of a species 
remains limited (Freville et al. 2007, p. 2669).
Threats Not Yet Fully Identified
    In addition to the small population size of Boechera pusilla, an 
unknown threat or threats may be present that is causing reduced 
numbers of the plant. The species was removed from the candidate list 
in 2000 based on the regulatory protections that were in place. Based 
on our current understanding of the species, these regulatory 
protections appear appropriate and sufficient. However, the species 
still has small population numbers that have declined overall since the 
implementation of these protections. We do not understand the nature of 
the threat or threats, but the reduced population numbers demonstrate 
that some type of threat is present. We have limited data to inform our 
understanding of what this threat could be. The decline could be linked 
to drought cycles, but we do not have sufficient data to correlate 
numbers of B. pusilla with drought. A disease could be present in the 
species, but we have no information to indicate disease is reducing the 
number of plants.
Summary of Factor E
    Boechera pusilla has a small population size that is confined to a 
small area because of habitat requirements. The species may be 
vulnerable to stochastic events due to its small population size. B. 
pusilla reproduces itself asexually, which may reduce some risks of a 
small population size, but does not fully eliminate this threat. 
Declines have occurred in the species, even after habitat protection 
measures were put in place. Although the population numbers increased 
from 2003 (150-250 flowering plants) to 2010 (350 flowering plants), 
numbers remain low, the plant appears to have an overall trend of 
decline, and this overall trend may continue in the foreseeable future. 
A viable population for the species may be 500 to 5,000 plants (Ladyman 
2005, p. 26), and species numbers are below that level. We are 
uncertain what is causing reduced population levels and consider the 
reduction to be an indicator that a threat is present for the species. 
We are not able to fully describe this threat. Some of the decline may 
be attributable to drought conditions, but we do not fully understand 
the cause of the decline. Additionally, disease may be present but has 
not been documented. The small population size creates a vulnerability 
that may work in combination with the threat that we are not able to 
explain. Therefore, the species appears likely to be in danger of 
extinction or likely to become so within the foreseeable future because 
of the combination of small population size and a threat that we cannot 
fully identify but that is manifest by an overall declining population.

Five Factor Evaluation Summary for Boechera pusilla

    Boechera pusilla has a threat that is not identified, but that is 
indicated by the small and declining population size. The population 
size may be declining from a variety of unknown causes, with drought or 
disease possibly contributing to the trend. The trend may have been 
reversed somewhat, but without improved population numbers, the species 
may reach a population level at which other stressors become threats. 
The species may already be below the minimum viable population, so 
other stressors may begin to present threats to the species. We are 
unable to determine how climate change may affect the species in the 
future. To the extent that we understand the species, other potential 
habitat-related threats have been removed through the implementation of 
Federal regulatory mechanisms and associated actions. Overutilization, 
predation, and the inadequacy of regulatory mechanisms are not viewed 
as threats to the species.

Finding

    As required by the Act, we considered the five factors in assessing 
whether Boechera pusilla is threatened or endangered throughout all of 
its range. We examined the best scientific and commercial information 
available regarding the past, present, and future threats faced by B. 
pusilla. We reviewed the petition, information available in our files, 
other available published and unpublished information, and we consulted 
with recognized B. pusilla experts and other Federal agencies.
    This status review identified threats to Boechera pusilla 
attributable to Factor E. The primary threat to the species is from a 
threat that is not fully identified, but is indicated by the species' 
small, declining population size. This threat to B. pusilla is not 
fully understood, but may be connected with drought conditions, 
disease, or other factors. Protective measures have been taken 
previously to maintain the species' habitat, but the species continues 
to experience declines. B. pusilla has only one population, with most 
of the individuals occurring in a single subpopulation. The range of 
the species is small due to limitations of a highly specialized 
habitat. Although population levels increased in 2010, the species is 
experiencing an overall pattern of decline that we anticipate will 
continue. B. pusilla numbers already may be below the minimum viable 
population requirement, so other vulnerabilities associated with the 
small population may now present threats to

[[Page 33958]]

the species. Therefore, the species appears likely to be in danger of 
extinction currently, or in the foreseeable future, as result of a 
threat that is not fully identified, but is manifest by an ongoing 
declining population trend.
    On the basis of the best scientific and commercial information 
available, we find that the petitioned action to list Boechera pusilla 
under the Act is warranted. We will make a determination on the status 
of the species as threatened or endangered when we do a proposed 
listing determination. However, as explained in more detail below, an 
immediate proposal of a regulation implementing this action is 
precluded by higher priority listing actions, and progress is being 
made to add or remove qualified species from the Lists of Endangered 
and Threatened Wildlife and Plants.
    We reviewed the available information to determine if the existing 
and foreseeable threats render the species at risk of extinction now 
such that issuing an emergency regulation temporarily listing the 
species under section 4(b)(7) of the Act is warranted. We determined 
that issuing an emergency regulation temporarily listing the species is 
not warranted for this species at this time, because threats to the 
species would not be further controlled with a change in status. 
Additionally, the most recent survey information suggests that, while 
the population has not rebounded to previous highs, the population 
declines also have not continued. However, if at any time we determine 
that issuing an emergency regulation temporarily listing Boechera 
pusilla is warranted, we will initiate this action at that time.

Listing Priority Number

    The Service adopted guidelines on September 21, 1983 (48 FR 43098), 
to establish a rational system for utilizing available resources for 
the highest priority species when adding species to the Lists of 
Endangered or Threatened Wildlife and Plants or reclassifying species 
listed as threatened to endangered status. These guidelines, titled 
``Endangered and Threatened Species Listing and Recovery Priority 
Guidelines'' address the immediacy and magnitude of threats, and the 
level of taxonomic distinctiveness by assigning priority in descending 
order to monotypic genera (genus with one species), full species, and 
subspecies (or equivalently, distinct population segments of 
vertebrates).
    As a result of our analysis of the best available scientific and 
commercial information, we have assigned Boechera pusilla a Listing 
Priority Number (LPN) of 8, based on our finding that the species faces 
threats that are of moderate magnitude and are imminent. These threats 
include a threat that is not fully identified that may work in 
combination with the small population. Our rationale for assigning B. 
pusilla an LPN of 8 is outlined below.
    Under the Service's guidelines, the magnitude of threat is the 
first criterion we look at when establishing a listing priority. The 
guidance indicates that species with the highest magnitude of threat 
are those species facing the greatest threats to their continued 
existence. These species receive the highest listing priority. We 
consider the threats that Boechera pusilla faces to be moderate in 
magnitude. Although the threat, as described in Factor E. Other Natural 
or Manmade Factors Affecting Its Continued Existence under Five Factor 
Evaluation for Boechera pusilla, is not fully understood, we know it 
exists as indicated by the declining population. Because we have not 
detected the source or nature of the threat, we consider the threat to 
be moderate in magnitude. The population levels have decreased 
significantly from the recorded high in 1988 (800 to 1,000), but they 
also increased between 2003 (150 to 250) and 2010 (350), so we do not 
consider the magnitude of the threat to be high. The threat is not 
fully understood, but is manifest by a declining population that may 
have stabilized somewhat; therefore, we consider the magnitude of the 
threat to be moderate.
    Under our LPN guidelines, the second criterion we consider in 
assigning a listing priority is the immediacy of threats. This 
criterion is intended to ensure that the species facing actual, 
identifiable threats are given priority over those for which threats 
are only potential or that are intrinsically vulnerable but are not 
known to be presently facing such threats. We consider the threat to 
Boechera pusilla as described in Factor E. Other Natural or Manmade 
Factors Affecting Its Continued Existence under Five Factor Evaluation 
for Boechera pusilla to be imminent because, although not fully 
identified, we have evidence that the species is currently facing a 
threat indicated by reduced population size. The threat appears to be 
ongoing, although we are unsure of the extent and timing of its effects 
on B. pusilla. The threat is occurring in the only known population in 
the United States, and the population may already be below the minimum 
viable population requirement, which may allow population reductions 
and increases in population vulnerability to occur more quickly in the 
future. We expect some additional declines will occur in the future, 
and if declines occur at rates similar to those in the past, population 
levels could be precariously low. Therefore, we consider the threat to 
be imminent.
    The third criterion in our Listing Priority Number guidance is 
intended to devote resources to those species representing highly 
distinctive or isolated gene pools as reflected by taxonomy. Boechera 
pusilla is a valid taxon at the species level and, therefore, receives 
a higher priority than subspecies, but a lower priority than species in 
a monotypic genus. Therefore, we assigned B. pusilla an LPN of 8.
    We will continue to monitor the threats to Boechera pusilla and the 
species' status on an annual basis, and should the magnitude or the 
imminence of the threats change, we will revisit our assessment of the 
LPN.
    While we conclude that listing Boechera pusilla is warranted, an 
immediate proposal to list this species is precluded by other higher 
priority listings, which we address in the Preclusion and Expeditious 
Progress section below. Because we have assigned B. pusilla an LPN of 
8, work on a proposed listing determination for the species is 
precluded by work on higher priority listing actions with absolute 
statutory, court-ordered, or court-approved deadlines and final listing 
determinations for those species that were proposed for listing with 
funds from Fiscal Year (FY) 2010. This work includes all the actions 
listed in the tables below under Preclusion and Expeditious Progress.

Preclusion and Expeditious Progress

    Preclusion is a function of the listing priority of a species in 
relation to the resources that are available and the cost and relative 
priority of competing demands for those resources. Thus, in any given 
FY, multiple factors dictate whether it will be possible to undertake 
work on a listing proposal regulation or whether promulgation of such a 
proposal is precluded by higher priority listing actions.
    The resources available for listing actions are determined through 
the annual Congressional appropriations process. The appropriation for 
the Listing Program is available to support work involving the 
following listing actions: Proposed and final listing rules; 90-day and 
12-month findings on petitions to add species to the Lists of 
Endangered and Threatened Wildlife and Plants (Lists) or to change the 
status

[[Page 33959]]

of a species from threatened to endangered; annual ``resubmitted'' 
petition findings on prior warranted-but-precluded petition findings as 
required under section 4(b)(3)(C)(i) of the Act; critical habitat 
petition findings; proposed and final rules designating critical 
habitat; and litigation-related, administrative, and program-management 
functions (including preparing and allocating budgets, responding to 
Congressional and public inquiries, and conducting public outreach 
regarding listing and critical habitat).
    The work involved in preparing various listing documents can be 
extensive and may include, but is not limited to: Gathering and 
assessing the best scientific and commercial data available and 
conducting analyses used as the basis for our decisions; writing and 
publishing documents; and obtaining, reviewing, and evaluating public 
comments and peer review comments on proposed rules and incorporating 
relevant information into final rules. The number of listing actions 
that we can undertake in a given year also is influenced by the 
complexity of those listing actions; that is, more complex actions 
generally are more costly. The median cost for preparing and publishing 
a 90-day finding is $39,276; for a 12-month finding, $100,690; for a 
proposed rule with critical habitat, $345,000; and for a final listing 
rule with critical habitat, the median cost is $305,000.
    We cannot spend more than is appropriated for the Listing Program 
without violating the Anti-Deficiency Act (see 31 U.S.C. 
1341(a)(1)(A)). In addition, in FY 1998 and for each FY since then, 
Congress has placed a statutory cap on funds which may be expended for 
the Listing Program, equal to the amount expressly appropriated for 
that purpose in that FY. This cap was designed to prevent funds 
appropriated for other functions under the Act (for example, recovery 
funds for removing species from the Lists), or for other Service 
programs, from being used for Listing Program actions (see House Report 
105-163, 105th Congress, 1st Session, July 1, 1997).
    Since FY 2002, the Service's budget has included a critical habitat 
subcap to ensure that some funds are available for other work in the 
Listing Program (``The critical habitat designation subcap will ensure 
that some funding is available to address other listing activities'' 
(House Report No. 107-103, 107th Congress, 1st Session, June 19, 
2001)). In FY 2002 and each year until FY 2006, the Service had to use 
virtually the entire critical habitat subcap to address court-mandated 
designations of critical habitat, and consequently none of the critical 
habitat subcap funds were available for other listing activities. In 
some FYs since 2006, we have been able to use some of the critical 
habitat subcap funds to fund proposed listing determinations for high-
priority candidate species. In other FYs, while we were unable to use 
any of the critical habitat subcap funds to fund proposed listing 
determinations, we did use some of this money to fund the critical 
habitat portion of some proposed listing determinations so that the 
proposed listing determination and proposed critical habitat 
designation could be combined into one rule, thereby being more 
efficient in our work. In FY 2011 we anticipate that we will be able to 
use some of the critical habitat subcap funds to fund proposed listing 
determinations.
    We make our determinations of preclusion on a nationwide basis to 
ensure that the species most in need of listing will be addressed first 
and also because we allocate our listing budget on a nationwide basis. 
Through the listing cap, the critical habitat subcap, and the amount of 
funds needed to address court-mandated critical habitat designations, 
Congress and the courts have in effect determined the amount of money 
available for other listing activities nationwide. Therefore, the funds 
in the listing cap, other than those needed to address court-mandated 
critical habitat for already listed species, set the limits on our 
determinations of preclusion and expeditious progress.
    Congress identified the availability of resources as the only basis 
for deferring the initiation of a rulemaking that is warranted. The 
Conference Report accompanying Pub. L. 97-304, which established the 
current statutory deadlines and the warranted-but-precluded finding, 
states that the amendments were ``not intended to allow the Secretary 
to delay commencing the rulemaking process for any reason other than 
that the existence of pending or imminent proposals to list species 
subject to a greater degree of threat would make allocation of 
resources to such a petition [that is, for a lower-ranking species] 
unwise.'' Although that statement appeared to refer specifically to the 
``to the maximum extent practicable'' limitation on the 90-day deadline 
for making a ``substantial information'' finding, that finding is made 
at the point when the Service is deciding whether or not to commence a 
status review that will determine the degree of threats facing the 
species, and therefore the analysis underlying the statement is more 
relevant to the use of the warranted-but-precluded finding, which is 
made when the Service has already determined the degree of threats 
facing the species and is deciding whether or not to commence a 
rulemaking.
    In FY 2010, $10,471,000 is the amount of money that Congress 
appropriated for the Listing Program (that is, the portion of the 
Listing Program funding not related to critical habitat designations 
for species that are already listed). Therefore, a proposed listing is 
precluded if pending proposals with higher priority will require 
expenditure of at least $10,471,000, and expeditious progress is the 
amount of work that can be achieved with $10,471,000. Since court 
orders requiring critical habitat work will not require use of all of 
the funds within the critical habitat subcap, we used $1,114,417 of our 
critical habitat subcap funds in order to work on as many of our 
required petition findings and listing determinations as possible. This 
brings the total amount of funds we had for listing actions in FY 2010 
to $11,585,417.
    The $11,585,417 was used to fund work in the following categories: 
Compliance with court orders and court-approved settlement agreements 
requiring that petition findings or listing determinations be completed 
by a specific date; section 4 (of the Act) listing actions with 
absolute statutory deadlines; essential litigation-related, 
administrative, and listing program-management functions; and high-
priority listing actions for some of our candidate species. For FY 
2011, on September 29, 2010, Congress passed a continuing resolution 
which provides funding at the FY 2010 enacted level. Until Congress 
appropriates funds for FY 2011, we will fund listing work based on the 
FY 2010 amount. In 2009, the responsibility for listing foreign species 
under the Act was transferred from the Division of Scientific 
Authority, International Affairs Program, to the Endangered Species 
Program. Therefore, starting in FY 2010, we use a portion of our 
funding to work on the actions described above as they apply to listing 
actions for foreign species. This has the potential to further reduce 
funding available for domestic listing actions. Although there are 
currently no foreign species issues included in our high-priority 
listing actions at this time, many actions have statutory or court-
approved settlement deadlines, thus increasing their priority. The 
budget allocations for each specific listing action are identified in 
the Service's FY 2011 Allocation Table (part of our administrative 
record).

[[Page 33960]]

    Based on our September 21, 1983, guidance for assigning an LPN for 
each candidate species (48 FR 43098), we have a significant number of 
species with a LPN of 2. Using this guidance, we assign each candidate 
an LPN of 1 to 12, depending on the magnitude of threats (high or 
moderate to low), immediacy of threats (imminent or nonimminent), and 
taxonomic status of the species (in order of priority: monotypic genus 
(a species that is the sole member of a genus); species; or part of a 
species (subspecies, distinct population segment, or significant 
portion of the range)). The lower the listing priority number, the 
higher the listing priority (that is, a species with an LPN of 1 would 
have the highest listing priority).
    Because of the large number of high-priority species, we have 
further ranked the candidate species with an LPN of 2 by using the 
following extinction-risk type criteria: International Union for the 
Conservation of Nature and Natural Resources (IUCN) Red list status/
rank, Heritage rank (provided by NatureServe), Heritage threat rank 
(provided by NatureServe), and species currently with fewer than 50 
individuals, or 4 or fewer populations. Those species with the highest 
IUCN rank (critically endangered), the highest Heritage rank (G1), the 
highest Heritage threat rank (substantial, imminent threats), and 
currently with fewer than 50 individuals, or fewer than 4 populations, 
originally comprised a group of approximately 40 candidate species 
(``Top 40''). These 40 candidate species have had the highest priority 
to receive funding to work on a proposed listing determination. As we 
work on proposed and final listing rules for those 40 candidates, we 
apply the ranking criteria to the next group of candidates with an LPN 
of 2 and 3 to determine the next set of highest priority candidate 
species. Finally, proposed rules for reclassification of threatened 
species to endangered are lower priority, since as listed species, they 
are already afforded the protection of the Act and implementing 
regulations. However, for efficiency reasons, we may choose to work on 
a proposed rule to reclassify a species to endangered if we can combine 
this with work that is subject to a court-determined deadline.
    We assigned Boechera pusilla an LPN of 8. This is based on our 
finding that the species faces immediate and moderate magnitude threats 
from a threat we do not fully understand but is manifest by reduced 
population levels that may be below the minimum viable population 
requirement. Under our 1983 Guidelines, a ``species'' facing imminent 
moderate-magnitude threats is assigned an LPN of 7, 8, or 9 depending 
on its taxonomic status. Because B. pusilla is a species, we assigned 
it an LPN of 8. Therefore, work on a proposed listing determination for 
B. pusilla is precluded by work on higher priority candidate species 
(i.e., species with LPN of 7); listing actions with absolute statutory, 
court ordered, or court-approved deadlines; and final listing 
determinations for those species that were proposed for listing with 
funds from previous FYs. This work includes all the actions listed in 
the tables below under expeditious progress.
    With our workload so much bigger than the amount of funds we have 
to accomplish it, it is important that we be as efficient as possible 
in our listing process. Therefore, as we work on proposed rules for the 
highest priority species in the next several years, we are preparing 
multi-species proposals when appropriate, and these may include species 
with lower priority if they overlap geographically or have the same 
threats as a species with an LPN of 2. In addition, we take into 
consideration the availability of staff resources when we determine 
which high-priority species will receive funding to minimize the amount 
of time and resources required to complete each listing action.
    As explained above, a determination that listing is warranted but 
precluded also must demonstrate that expeditious progress is being made 
to add and remove qualified species to and from the Lists of Endangered 
and Threatened Wildlife and Plants. As with our ``precluded'' finding, 
the evaluation of whether progress in adding qualified species to the 
Lists has been expeditious is a function of the resources available for 
listing and the competing demands for those funds. (Although we do not 
discuss it in detail here, we also are making expeditious progress in 
removing species from the list under the Recovery program in light of 
the resource available for delisting, which is funded by a separate 
line item in the budget of the Endangered Species Program. During FY 
2010, we have completed two proposed delisting rules and two final 
delisting rules.) Given the limited resources available for listing, we 
find that we made expeditious progress in FY 2010 in the Listing 
Program and are making expeditious progress in FY 2011. This progress 
included preparing and publishing the following determinations:

                                  FY 2010 and FY 2011 Completed Listing Actions
----------------------------------------------------------------------------------------------------------------
     Publication date                 Title                   Actions                      FR pages
----------------------------------------------------------------------------------------------------------------
10/08/2009................  Listing Lepidium           Final Listing         74 FR 52013-52064.
                             papilliferum (Slickspot    Threatened.
                             Peppergrass) as a
                             Threatened Species
                             Throughout Its Range.
10/27/2009................  90-day Finding on a        Notice of 90-day      74 FR 55177-55180.
                             Petition To List the       Petition Finding,
                             American Dipper in the     Not substantial.
                             Black Hills of South
                             Dakota as Threatened or
                             Endangered.
10/28/2009................  Status Review of Arctic    Notice of Intent to   74 FR 55524-55525.
                             Grayling (Thymallus        Conduct Status
                             arcticus) in the Upper     Review for Listing
                             Missouri River System.     Decision.
11/03/2009................  Listing the British        Proposed Listing      74 FR 56757-56770.
                             Columbia Distinct          Threatened.
                             Population Segment of
                             the Queen Charlotte
                             Goshawk Under the
                             Endangered Species Act:
                             Proposed rule.
11/03/2009................  Listing the Salmon-        Proposed Listing      74 FR 56770-56791.
                             Crested Cockatoo as        Threatened.
                             Threatened Throughout
                             Its Range with Special
                             Rule.
11/23/2009................  Status Review of Gunnison  Notice of Intent to   74 FR 61100-61102.
                             sage-grouse                Conduct Status
                             (Centrocercus minimus).    Review for Listing
                                                        Decision.
12/03/2009................  12-Month Finding on a      Notice of 12-month    74 FR 63343-63366.
                             Petition to List the       petition finding,
                             Black-tailed Prairie Dog   Not warranted.
                             as Threatened or
                             Endangered.
12/03/2009................  90-Day Finding on a        Notice of 90-day      74 FR 63337-63343.
                             Petition to List           Petition Finding,
                             Sprague's Pipit as         Substantial.
                             Threatened or Endangered.

[[Page 33961]]

 
12/15/2009................  90-Day Finding on          Notice of 90-day      74 FR 66260-66271.
                             Petitions To List Nine     Petition Finding,
                             Species of Mussels From    Substantial.
                             Texas as Threatened or
                             Endangered With Critical
                             Habitat.
12/16/2009................  Partial 90-Day Finding on  Notice of 90-day      74 FR 66865-66905.
                             a Petition to List 475     Petition Finding,
                             Species in the             Not substantial &
                             Southwestern United        Substantial.
                             States as Threatened or
                             Endangered With Critical
                             Habitat.
12/17/2009................  12-month Finding on a      Notice of 12-month    74 FR 66937-66950.
                             Petition To Change the     petition finding,
                             Final Listing of the       Warranted but
                             Distinct Population        precluded.
                             Segment of the Canada
                             Lynx To Include New
                             Mexico.
01/05/2010................  Listing Foreign Bird       Proposed Listing      75 FR 605-649.
                             Species in Peru &          Endangered.
                             Bolivia as Endangered
                             Throughout Their Range.
01/05/2010................  Listing Six Foreign Birds  Proposed Listing      75 FR 286-310.
                             as Endangered Throughout   Endangered.
                             Their Range.
01/05/2010................  Withdrawal of Proposed     Proposed rule,        75 FR 310-316.
                             Rule to List Cook's        withdrawal.
                             Petrel.
01/05/2010................  Final Rule to List the     Final Listing         75 FR 235-250.
                             Galapagos Petrel &         Threatened.
                             Heinroth's Shearwater as
                             Threatened Throughout
                             Their Ranges.
01/20/2010................  Initiation of Status       Notice of Intent to   75 FR 3190-3191.
                             Review for Agave           Conduct Status
                             eggersiana & Solanum       Review for Listing
                             conocarpum.                Decision.
02/09/2010................  12-month Finding on a      Notice of 12-month    75 FR 6437-6471.
                             Petition to List the       petition finding,
                             American Pika as           Not warranted.
                             Threatened or Endangered.
02/25/2010................  12-Month Finding on a      Notice of 12-month    75 FR 8601-8621.
                             Petition To List the       petition finding,
                             Sonoran Desert             Not warranted.
                             Population of the Bald
                             Eagle as a Threatened or
                             Endangered Distinct
                             Population Segment.
02/25/2010................  Withdrawal of Proposed     Withdrawal of         75 FR 8621-8644.
                             Rule To List the           Proposed Rule to
                             Southwestern Washington/   List.
                             Columbia River Distinct
                             Population Segment of
                             Coastal Cutthroat Trout
                             (Oncorhynchus clarki
                             clarki) as Threatened.
03/18/2010................  90-Day Finding on a        Notice of 90-day      75 FR 13068-13071.
                             Petition to List the       Petition Finding,
                             Berry Cave salamander as   Substantial.
                             Endangered.
03/23/2010................  90-Day Finding on a        Notice of 90-day      75 FR 13717-13720.
                             Petition to List the       Petition Finding,
                             Southern Hickorynut        Not substantial.
                             Mussel (Obovaria
                             jacksoniana) as
                             Endangered or Threatened.
03/23/2010................  90-Day Finding on a        Notice of 90-day      75 FR 13720-13726.
                             Petition to List the       Petition Finding,
                             Striped Newt as            Substantial.
                             Threatened.
03/23/2010................  12-Month Findings for      Notice of 12-month    75 FR 13910-14014.
                             Petitions to List the      petition finding,
                             Greater Sage-Grouse        Warranted but
                             (Centrocercus              precluded.
                             urophasianus) as
                             Threatened or Endangered.
03/31/2010................  12-Month Finding on a      Notice of 12-month    75 FR 16050-16065.
                             Petition to List the       petition finding,
                             Tucson Shovel-Nosed        Warranted but
                             Snake (Chionactis          precluded.
                             occipitalis klauberi) as
                             Threatened or Endangered
                             with Critical Habitat.
04/05/2010................  90-Day Finding on a        Notice of 90-day      75 FR 17062-17070.
                             Petition To List           Petition Finding,
                             Thorne's Hairstreak        Substantial.
                             Butterfly as threatened
                             or Endangered.
04/06/2010................  12-month Finding on a      Notice of 12-month    75 FR 17352-17363.
                             Petition To List the       petition finding,
                             Mountain Whitefish in      Not warranted.
                             the Big Lost River,
                             Idaho, as Endangered or
                             Threatened.
04/06/2010................  90-Day Finding on a        Notice of 90-day      75 FR 17363-17367.
                             Petition to List a         Petition Finding,
                             Stonefly (Isoperla         Not substantial.
                             jewetti) & a Mayfly
                             (Fallceon eatoni) as
                             Threatened or Endangered
                             with Critical Habitat.
04/7/2010.................  12-Month Finding on a      Notice of 12-month    75 FR 17667-17680.
                             Petition to Reclassify     petition finding,
                             the Delta Smelt From       Warranted but
                             Threatened to Endangered   precluded.
                             Throughout Its Range.
04/13/2010................  Determination of           Final Listing         75 FR 18959-19165.
                             Endangered Status for 48   Endangered.
                             Species on Kauai &
                             Designation of Critical
                             Habitat.
04/15/2010................  Initiation of Status       Notice of Initiation  75 FR 19591-19592.
                             Review of the North        of Status Review
                             American Wolverine in      for Listing
                             the Contiguous United      Decision.
                             States.
04/15/2010................  12-Month Finding on a      Notice of 12-month    75 FR 19592-19607.
                             Petition to List the       petition finding,
                             Wyoming Pocket Gopher as   Not warranted.
                             Endangered or Threatened
                             with Critical Habitat.
04/16/2010................  90-Day Finding on a        Notice of 90-day      75 FR 19925-19935.
                             Petition to List a         Petition Finding,
                             Distinct Population        Substantial.
                             Segment of the Fisher in
                             Its United States
                             Northern Rocky Mountain
                             Range as Endangered or
                             Threatened with Critical
                             Habitat.
04/20/2010................  Initiation of Status       Notice of Initiation  75 FR 20547-20548.
                             Review for Sacramento      of Status Review
                             splittail (Pogonichthys    for Listing
                             macrolepidotus).           Decision.
04/26/2010................  90-Day Finding on a        Notice of 90-day      75 FR 21568-21571.
                             Petition to List the       Petition Finding,
                             Harlequin Butterfly as     Substantial.
                             Endangered.
04/27/2010................  12-Month Finding on a      Notice of 12-month    75 FR 22012-22025.
                             Petition to List Susan's   petition finding,
                             Purse-making Caddisfly     Not warranted.
                             (Ochrotrichia susanae)
                             as Threatened or
                             Endangered.

[[Page 33962]]

 
04/27/2010................  90-day Finding on a        Notice of 90-day      75 FR 22063-22070.
                             Petition to List the       Petition Finding,
                             Mohave Ground Squirrel     Substantial.
                             as Endangered with
                             Critical Habitat.
05/04/2010................  90-Day Finding on a        Notice of 90-day      75 FR 23654-23663.
                             Petition to List Hermes    Petition Finding,
                             Copper Butterfly as        Substantial.
                             Threatened or Endangered.
06/01/2010................  90-Day Finding on a        Notice of 90-day      75 FR 30313-30318.
                             Petition To List           Petition Finding,
                             Castanea pumila var.       Substantial.
                             ozarkensis.
06/01/2010................  12-month Finding on a      Notice of 12-month    75 FR 30338-30363.
                             Petition to List the       petition finding,
                             White-tailed Prairie Dog   Not warranted.
                             as Endangered or
                             Threatened.
06/09/2010................  90-Day Finding on a        Notice of 90-day      75 FR 32728-32734.
                             Petition To List van       Petition Finding,
                             Rossem's Gull-billed       Substantial.
                             Tern as Endangered or
                             Threatened.
06/16/2010................  90-Day Finding on Five     Notice of 90-day      75 FR 34077-34088.
                             Petitions to List Seven    Petition Finding,
                             Species of Hawaiian        Substantial.
                             Yellow-faced Bees as
                             Endangered.
06/22/2010................  12-Month Finding on a      Notice of 12-month    75 FR 35398-35424.
                             Petition to List the       petition finding,
                             Least Chub as Threatened   Warranted but
                             or Endangered.             precluded.
06/23/2010................  90-Day Finding on a        Notice of 90-day      75 FR 35746-35751.
                             Petition to List the       Petition Finding,
                             Honduran Emerald           Substantial.
                             Hummingbird as
                             Endangered.
06/23/2010................  Listing Ipomopsis          Proposed Listing      75 FR 35721-35746.
                             polyantha (Pagosa          Endangered Proposed
                             Skyrocket) as Endangered   Listing Threatened.
                             Throughout Its Range, &
                             Listing Penstemon
                             debilis (Parachute
                             Beardtongue) & Phacelia
                             submutica (DeBeque
                             Phacelia) as Threatened
                             Throughout Their Range.
06/24/2010................  Listing the Flying Earwig  Final Listing         75 FR 35990-36012.
                             Hawaiian Damselfly &       Endangered.
                             Pacific Hawaiian
                             Damselfly As Endangered
                             Throughout Their Ranges.
06/24/2010................  Listing the Cumberland     Proposed Listing      75 FR 36035-36057.
                             Darter, Rush Darter,       Endangered.
                             Yellowcheek Darter,
                             Chucky Madtom, & Laurel
                             Dace as Endangered
                             Throughout Their Ranges.
06/29/2010................  Listing the Mountain       Reinstatement of      75 FR 37353-37358.
                             Plover as Threatened.      Proposed Listing
                                                        Threatened.
07/20/2010................  90-Day Finding on a        Notice of 90-day      75 FR 42033-42040.
                             Petition to List Pinus     Petition Finding,
                             albicaulis (Whitebark      Substantial.
                             Pine) as Endangered or
                             Threatened with Critical
                             Habitat.
07/20/2010................  12-Month Finding on a      Notice of 12-month    75 FR 42040-42054.
                             Petition to List the       petition finding,
                             Amargosa Toad as           Not warranted.
                             Threatened or Endangered.
07/20/2010................  90-Day Finding on a        Notice of 90-day      75 FR 42059-42066.
                             Petition to List the       Petition Finding,
                             Giant Palouse Earthworm    Substantial.
                             (Driloleirus americanus)
                             as Threatened or
                             Endangered.
07/27/2010................  Determination on Listing   Final Listing         75 FR 43844-43853.
                             the Black-Breasted         Endangered.
                             Puffleg as Endangered
                             Throughout its Range;
                             Final Rule.
07/27/2010................  Final Rule to List the     Final Listing         75 FR 43853-43864.
                             Medium Tree-Finch          Endangered.
                             (Camarhynchus pauper) as
                             Endangered Throughout
                             Its Range.
08/03/2010................  Determination of           Final Listing         75 FR 45497-45527.
                             Threatened Status for      Threatened.
                             Five Penguin Species.
08/04/2010................  90-Day Finding on a        Notice of 90-day      75 FR 46894-46898.
                             Petition To List the       Petition Finding,
                             Mexican Gray Wolf as an    Substantial.
                             Endangered Subspecies
                             With Critical Habitat.
08/10/2010................  90-Day Finding on a        Notice of 90-day      75 FR 48294-48298.
                             Petition to List           Petition Finding,
                             Arctostaphylos             Substantial.
                             franciscana as
                             Endangered with Critical
                             Habitat.
08/17/2010................  Listing Three Foreign      Final Listing         75 FR 50813-50842.
                             Bird Species from Latin    Endangered.
                             America & the Caribbean
                             as Endangered Throughout
                             Their Range.
08/17/2010................  90-Day Finding on a        Notice of 90-day      75 FR 50739-50742.
                             Petition to List Brian     Petition Finding,
                             Head Mountainsnail as      Not substantial.
                             Endangered or Threatened
                             with Critical Habitat.
08/24/2010................  90-Day Finding on a        Notice of 90-day      75 FR 51969-51974.
                             Petition to List the       Petition Finding,
                             Oklahoma Grass Pink        Substantial.
                             Orchid as Endangered or
                             Threatened.
09/01/2010................  12-Month Finding on a      Notice of 12-month    75 FR 53615-53629.
                             Petition to List the       petition finding,
                             White-Sided Jackrabbit     Not warranted.
                             as Threatened or
                             Endangered.
09/08/2010................  Proposed Rule To List the  Proposed Listing      75 FR 54561-54579.
                             Ozark Hellbender           Endangered.
                             Salamander as Endangered.
09/08/2010................  Revised 12-Month Finding   Notice of 12-month    75 FR 54707-54753.
                             to List the Upper          petition finding,
                             Missouri River Distinct    Warranted but
                             Population Segment of      precluded.
                             Arctic Grayling as
                             Endangered or Threatened.
09/09/2010................  12-Month Finding on a      Notice of 12-month    75 FR 54822-54845.
                             Petition to List the       petition finding,
                             Jemez Mountains            Warranted but
                             Salamander (Plethodon      precluded.
                             neomexicanus) as
                             Endangered or Threatened
                             with Critical Habitat.
09/15/2010................  12-Month Finding on a      Notice of 12-month    75 FR 56028-56050.
                             Petition to List           petition finding,
                             Sprague's Pipit as         Warranted but
                             Endangered or Threatened   precluded.
                             Throughout Its Range.
09/22/2010................  12-Month Finding on a      Notice of 12-month    75 FR 57720-57734.
                             Petition to List Agave     petition finding,
                             eggersiana (no common      Warranted but
                             name) as Endangered.       precluded.

[[Page 33963]]

 
09/28/2010................  Determination of           Final Listing         75 FR 59645-59656.
                             Endangered Status for      Endangered.
                             the African Penguin.
09/28/2010................  Determination for the      Notice of 12-month    75 FR 59803-59863.
                             Gunnison Sage-grouse as    petition finding,
                             a Threatened or            Warranted but
                             Endangered Species.        precluded.
09/30/2010................  12-Month Finding on a      Notice of 12-month    75 FR 60515-60561.
                             Petition to List the       petition finding,
                             Pygmy Rabbit as            Not warranted.
                             Endangered or Threatened.
10/06/2010................  Endangered Status for the  Proposed Listing      75 FR 61664-61690.
                             Altamaha Spinymussel &     Endangered.
                             Designation of Critical
                             Habitat.
10/7/2010.................  12-month Finding on a      Notice of 12-month    75 FR 62070-62095.
                             Petition to list the       petition finding,
                             Sacramento Splittail as    Not warranted.
                             Endangered or Threatened.
10/28/2010................  Endangered Status &        Proposed Listing      75 FR 66481-66552.
                             Designation of Critical    Endangered
                             Habitat for Spikedace &    (uplisting).
                             Loach Minnow.
11/2/2010.................  90-Day Finding on a        Notice of 90-day      75 FR 67341-67343.
                             Petition to List the Bay   Petition Finding,
                             Springs Salamander as      Not substantial.
                             Endangered.
11/2/2010.................  Determination of           Final Listing         75 FR 67511-67550.
                             Endangered Status for      Endangered.
                             the Georgia Pigtoe
                             Mussel, Interrupted
                             Rocksnail, & Rough
                             Hornsnail & Designation
                             of Critical Habitat.
11/2/2010.................  Listing the Rayed Bean &   Proposed Listing      75 FR 67551-67583.
                             Snuffbox as Endangered.    Endangered.
11/4/2010.................  12-Month Finding on a      Notice of 12-month    75 FR 67925-67944.
                             Petition to List Cirsium   petition finding,
                             wrightii (Wright's Marsh   Warranted but
                             Thistle) as Endangered     precluded.
                             or Threatened.
----------------------------------------------------------------------------------------------------------------

     Our expeditious progress also includes work on listing actions 
that we funded in FY 2010 and FY 2011 but have not yet been completed 
to date. These actions are listed below. Actions in the top section of 
the table are being conducted under a deadline set by a court. Actions 
in the middle section of the table are being conducted to meet 
statutory timelines, that is, timelines required under the Act. Actions 
in the bottom section of the table are high-priority listing actions. 
These actions include work primarily on species with an LPN of 2, and, 
as discussed above, selection of these species is partially based on 
available staff resources, and when appropriate, include species with a 
lower priority if they overlap geographically or have the same threats 
as the species with the high priority. Including these species together 
in the same proposed rule results in considerable savings in time and 
funding, as compared to preparing separate proposed rules for each of 
them in the future.

                           Actions Funded in FY 2010 and FY 2011 but Not Yet Completed
----------------------------------------------------------------------------------------------------------------
                Species                                                   Action
----------------------------------------------------------------------------------------------------------------
                               Actions Subject to Court Order/Settlement Agreement
----------------------------------------------------------------------------------------------------------------
6 Birds from Eurasia...................  Final listing determination.
Flat-tailed horned lizard..............  Final listing determination.
Mountain plover \4\....................  Final listing determination.
6 Birds from Peru......................  Proposed listing determination.
Pacific walrus.........................  12-month petition finding.
Wolverine..............................  12-month petition finding.
Solanum conocarpum.....................  12-month petition finding.
Desert tortoise--Sonoran population....  12-month petition finding.
Thorne's Hairstreak butterfly \3\......  12-month petition finding.
Hermes copper butterfly \3\............  12-month petition finding.
Utah prairie dog (uplisting)...........  90-day petition finding.
----------------------------------------------------------------------------------------------------------------
                                        Actions With Statutory Deadlines
----------------------------------------------------------------------------------------------------------------
Casey's june beetle....................  Final listing determination.
7 Bird species from Brazil.............  Final listing determination.
Southern rockhopper penguin--Campbell    Final listing determination.
 Plateau population.
5 Bird species from Colombia and         Final listing determination.
 Ecuador.
Queen Charlotte goshawk................  Final listing determination.
5 species southeast fish (Cumberland     Final listing determination.
 darter, rush darter, yellowcheek
 darter, chucky madtom, and laurel
 dace) \4\.
Ozark hellbender \4\...................  Final listing determination.
Altamaha spinymussel \3\...............  Final listing determination.
3 Colorado plants (Ipomopsis polyantha   Final listing determination.
 (Pagosa Skyrocket), Penstemon debilis
 (Parachute Beardtongue), and Phacelia
 submutica (DeBeque Phacelia)) \4\.
Salmon crested cockatoo................  Final listing determination.
Loggerhead sea turtle (assist National   Final listing determination.
 Marine Fisheries Service) \5\.
2 mussels (rayed bean (LPN = 2),         Final listing determination.
 snuffbox No LPN) \5\.
Mt Charleston blue \5\.................  Proposed listing determination.
CA golden trout \4\....................  12-month petition finding.
Black-footed albatross.................  12-month petition finding.

[[Page 33964]]

 
Mount Charleston blue butterfly........  12-month petition finding.
Mojave fringe-toed lizard \1\..........  12-month petition finding.
Kokanee--Lake Sammamish population \1\.  12-month petition finding.
Cactus ferruginous pygmy-owl \1\.......  12-month petition finding.
Northern leopard frog..................  12-month petition finding.
Tehachapi slender salamander...........  12-month petition finding.
Coqui Llanero..........................  12-month petition finding/Proposed listing.
Dusky tree vole........................  12-month petition finding.
3 MT invertebrates (mist                 12-month petition finding.
 forestfly(Lednia tumana), Oreohelix
 sp.3, Oreohelix sp. 31) from 206
 species petition.
5 UT plants (Astragalus hamiltonii,      12-month petition finding.
 Eriogonum soredium, Lepidium ostleri,
 Penstemon flowersii, Trifolium
 friscanum) from 206 species petition.
2 CO plants (Astragalus microcymbus,     12-month petition finding.
 Astragalus schmolliae) from 206
 species petition.
5 WY plants (Abronia ammophila,          12-month petition finding.
 Agrostis rossiae, Astragalus
 proimanthus, Boechere (Arabis)
 pusilla, Penstemon gibbensii) from 206
 species petition.
Leatherside chub (from 206 species       12-month petition finding.
 petition).
Frigid ambersnail (from 206 species      12-month petition finding.
 petition) \3\.
Platte River caddisfly (from 206         12-month petition finding.
 species petition) \5\.
Gopher tortoise--eastern population....  12-month petition finding.
Grand Canyon scorpion (from 475 species  12-month petition finding.
 petition).
Anacroneuria wipukupa (a stonefly from   12-month petition finding.
 475 species petition) \4\.
Rattlesnake-master borer moth (from 475  12-month petition finding.
 species petition) \3\.
3 Texas moths (Ursia furtiva,            12-month petition finding.
 Sphingicampa blanchardi, Agapema
 galbina) (from 475 species petition).
2 Texas shiners (Cyprinella sp.,         12-month petition finding.
 Cyprinella lepida) (from 475 species
 petition).
3 South Arizona plants (Erigeron         12-month petition finding.
 piscaticus, Astragalus hypoxylus,
 Amoreuxia gonzalezii) (from 475
 species petition).
5 Central Texas mussel species (3 from   12-month petition finding.
 475 species petition).
14 parrots (foreign species)...........  12-month petition finding.
Berry Cave salamander \1\..............  12-month petition finding.
Striped Newt \1\.......................  12-month petition finding.
Fisher--Northern Rocky Mountain Range    12-month petition finding.
 \1\.
Mohave Ground Squirrel \1\.............  12-month petition finding.
Puerto Rico Harlequin Butterfly \3\....  12-month petition finding.
Western gull-billed tern...............  12-month petition finding.
Ozark chinquapin (Castanea pumila var.   12-month petition finding.
 ozarkensis) \4\.
HI yellow-faced bees...................  12-month petition finding.
Giant Palouse earthworm................  12-month petition finding.
Whitebark pine.........................  12-month petition finding.
OK grass pink (Calopogon oklahomensis)   12-month petition finding.
 \1\.
Ashy storm-petrel \5\..................  12-month petition finding.
Southeastern pop snowy plover &          90-day petition finding.
 wintering pop. of piping plover \1\.
Eagle Lake trout \1\...................  90-day petition finding.
Smooth-billed ani \1\..................  90-day petition finding.
32 Pacific Northwest mollusks species    90-day petition finding.
 (snails and slugs) \1\.
42 snail species (Nevada & Utah).......  90-day petition finding.
Red knot roselaari subspecies..........  90-day petition finding.
Peary caribou..........................  90-day petition finding.
Plains bison...........................  90-day petition finding.
Spring Mountains checkerspot butterfly.  90-day petition finding.
Spring pygmy sunfish...................  90-day petition finding.
Bay skipper............................  90-day petition finding.
Unsilvered fritillary..................  90-day petition finding.
Texas kangaroo rat.....................  90-day petition finding.
Spot-tailed earless lizard.............  90-day petition finding.
Eastern small-footed bat...............  90-day petition finding.
Northern long-eared bat................  90-day petition finding.
Prairie chub...........................  90-day petition finding.
10 species of Great Basin butterfly....  90-day petition finding.
6 sand dune (scarab) beetles...........  90-day petition finding.
Golden-winged warbler \4\..............  90-day petition finding.
Sand-verbena moth......................  90-day petition finding.
404 Southeast species..................  90-day petition finding.
Franklin's bumble bee \4\..............  90-day petition finding.
2 Idaho snowflies (straight snowfly &    90-day petition finding.
 Idaho snowfly) \4\.
American eel \4\.......................  90-day petition finding.
Gila monster (Utah population) \4\.....  90-day petition finding.
Arapahoe snowfly \4\...................  90-day petition finding.
Leona's little blue \4\................  90-day petition finding.
Aztec gilia \5\........................  90-day petition finding.
White-tailed ptarmigan \5\.............  90-day petition finding.
San Bernardino flying squirrel \5\.....  90-day petition finding.

[[Page 33965]]

 
Bicknell's thrush \5\..................  90-day petition finding.
Sonoran talussnail \5\.................  90-day petition finding.
2 AZ Sky Island plants (Graptopetalum    90-day petition finding.
 bartrami & Pectis imberbis) \5\.
I'iwi \5\..............................  90-day petition finding.
                                        ------------------------------------------------------------------------
                                          High-Priority Listing Actions
----------------------------------------------------------------------------------------------------------------
19 Oahu candidate species \2\ (16        Proposed listing.
 plants, 3 damselflies) (15 with LPN =
 2, 3 with LPN = 3, 1 with LPN =9).
19 Maui-Nui candidate species \2\ (16    Proposed listing.
 plants, 3 tree snails) (14 with LPN =
 2, 2 with LPN = 3, 3 with LPN = 8).
Dune sagebrush lizard (formerly Sand     Proposed listing.
 dune lizard) \4\ (LPN = 2).
2 Arizona springsnails \2\ (Pyrgulopsis  Proposed listing.
 bernadina (LPN = 2), Pyrgulopsis
 trivialis (LPN = 2)).
New Mexico springsnail \2\ (Pyrgulopsis  Proposed listing.
 chupaderae (LPN = 2).
2 mussels \2\ (sheepnose (LPN = 2),      Proposed listing.
 spectaclecase (LPN = 4),).
8 Gulf Coast mussels (southern           Proposed listing.
 kidneyshell (LPN = 2), round
 ebonyshell (LPN = 2), Alabama
 pearlshell (LPN = 2), southern
 sandshell (LPN = 5), fuzzy pigtoe (LPN
 = 5), Choctaw bean (LPN = 5), narrow
 pigtoe (LPN = 5), and tapered pigtoe
 (LPN = 11)) \4\.
Umtanum buckwheat (LPN = 2) \4\........  Proposed listing.
Grotto sculpin (LPN = 2) \4\...........  Proposed listing.
2 Arkansas mussels (Neosho mucket (LPN   Proposed listing.
 =2) & Rabbitsfoot (LPN = 9)) \4\.
Diamond darter (LPN = 2) \4\...........  Proposed listing.
Gunnison sage-grouse (LPN =2) \4\......  Proposed listing.
Miami blue (LPN = 3) \3\...............  Proposed listing.
4 Texas salamanders (Austin blind        Proposed listing.
 salamander (LPN = 2), Salado
 salamander (LPN = 2), Georgetown
 salamander (LPN = 8), Jollyville
 Plateau (LPN = 8)) \3\.
5 SW aquatics (Gonzales Spring Snail     Proposed listing.
 (LPN = 2), Diamond Y springsnail (LPN
 =2), Phantom springsnail (LPN = 2),
 Phantom Cave snail (LPN = 2),
 Diminutive amphipod (LPN = 2)) \3\.
2 Texas plants (Texas golden gladecress  Proposed listing.
 (Leavenworthia texana) (LPN = 2),
 Neches River rose-mallow (Hibiscus
 dasycalyx) (LPN = 2)) \3\.
FL bonneted bat (LPN =2) \3\...........  Proposed listing.
Kittlitz's murrelet (LPN = 2) \5\......  Proposed listing.
Umtanum buckwheat (LPN = 2) \3\........  Proposed listing.
21 Big Island (HI) species \5\           Proposed listing.
 (includes 8 candidate species--5
 plants & 3 animals; 4 with LPN = 2, 1
 with LPN = 3, 1 with LPN = 4, 2 with
 LPN = 8).
Oregon spotted frog (LPN = 2) \5\......  Proposed listing.
2 TN River mussels (fluted kidneyshell   Proposed listing.
 (LPN = 2), slabside pearlymussel (LPN
 = 2) \5\.
Jemez Mountain salamander (LPN = 2) \5\  Proposed listing.
----------------------------------------------------------------------------------------------------------------
\1\ Funds for listing actions for these species were provided in previous FYs.
\2\ Although funds for these high-priority listing actions were provided in FY 2008 or 2009, due to the
  complexity of these actions and competing priorities, these actions are still being developed.
\3\ Partially funded with FY 2010 funds and FY 2011 funds.
\4\ Funded with FY 2010 funds.
\5\ Funded with FY 2011 funds.

    We have endeavored to make our listing actions as efficient and 
timely as possible, given the requirements of the relevant law and 
regulations, and constraints relating to workload and personnel. We are 
continually considering ways to streamline processes or achieve 
economies of scale, such as by batching related actions together. Given 
our limited budget for implementing section 4 of the Act, these actions 
described above collectively constitute expeditious progress.
    Boechera pusilla will be added to the list of candidate species 
upon publication of this 12-month finding. We will continue to evaluate 
this species as new information becomes available. Continuing review 
will determine if a change in status is warranted, including the need 
to make prompt use of emergency listing procedures.
    We intend that any proposed listing determination for Boechera 
pusilla will be as accurate as possible. Therefore, we will continue to 
accept additional information and comments from all concerned 
governmental agencies, the scientific community, industry, or any other 
interested party concerning this finding.

References Cited

    A complete list of references cited is available on the Internet at 
http://www.regulations.gov and upon request from the Wyoming Ecological 
Services Field Office (see ADDRESSES section).

Author(s)

    The primary authors of this notice are the staff members of the 
Wyoming Ecological Services Field Office.

    Authority:  The authority for this section is section 4 of the 
Endangered Species Act of 1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: May 16, 2011.
Rowan W. Gould,
Acting Director, Fish and Wildlife Service.
[FR Doc. 2011-13910 Filed 6-8-11; 8:45 am]
BILLING CODE 4310-55-P