[Federal Register Volume 83, Number 39 (Tuesday, February 27, 2018)]
[Rules and Regulations]
[Pages 8576-8603]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-03769]



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Vol. 83

Tuesday,

No. 39

February 27, 2018

Part II





 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; Removing Oenothera avita 
ssp. eurekensis From the Federal List of Endangered and Threatened 
Plants, and Reclassification of Swallenia alexandrae From Endangered to 
Threatened; Final Rule

  Federal Register / Vol. 83 , No. 39 / Tuesday, February 27, 2018 / 
Rules and Regulations  

[[Page 8576]]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R8-ES-2013-0131; FXES11130900000-145-FF09E42000]
RIN 1018-AW04


Endangered and Threatened Wildlife and Plants; Removing Oenothera 
avita ssp. eurekensis From the Federal List of Endangered and 
Threatened Plants, and Reclassification of Swallenia alexandrae From 
Endangered to Threatened

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule and availability of post-delisting monitoring plan.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), are removing 
Oenothera avita ssp. eurekensis, which is now recognized as Oenothera 
californica ssp. eurekensis (with a common name of Eureka Valley 
evening-primrose, Eureka evening-primrose, or Eureka Dunes evening-
primrose) from the Federal List of Endangered and Threatened Plants. We 
are also reclassifying Swallenia alexandrae (with a common name of 
Eureka dune grass, Eureka dunegrass, or Eureka Valley dune grass) from 
an endangered to a threatened species. For Eureka Valley evening-
primrose, this action is based on our evaluation of the best available 
scientific and commercial information, including comments received, 
which indicates that the threats have been eliminated or reduced to the 
point that the subspecies no longer meets the definition of an 
endangered species or a threatened species under the Endangered Species 
Act of 1973, as amended (Act).
    For Eureka dune grass, this reclassification is based on our 
evaluation of the best available scientific and commercial information, 
including comments received. We conclude that the stressors acting upon 
Eureka dune grass are of sufficient imminence, scope, or magnitude to 
indicate that they are continuing to result in impacts at either the 
population or rangewide scales, albeit to a lesser degree than at the 
time of listing, and we find that Eureka dune grass meets the statutory 
definition of a threatened species (i.e., the stressors impacting the 
species or its habitat are of sufficient magnitude, scope, or imminence 
to indicate that the species is likely to become an endangered species 
in the foreseeable future throughout all or a significant portion of 
its range).

DATES: This final rule becomes effective March 29, 2018.

ADDRESSES: Comments, materials received, and supporting documentation 
used in preparation of this final rule are available on the internet at 
http://www.regulations.gov under Docket No. FWS-R8-ES-2013-0131. 
Additionally, comments, materials, and supporting documentation are 
available for public inspection by appointment (see FOR FURTHER 
INFORMATION CONTACT below). The post-delisting monitoring plan for 
Oenothera californica ssp. eurekensis is available on our Endangered 
Species Program's national website (http://endangered.fws.gov) and on 
the internet at http://www.regulations.gov at Docket No. FWS-R8-ES-
2013-0131.

FOR FURTHER INFORMATION CONTACT: Mendel Stewart, Field Supervisor, 
Carlsbad Fish and Wildlife Office, 2177 Salk Avenue, Suite 250, 
Carlsbad, CA 92008; telephone 760-431-9440; facsimile 760-431-5901. If 
you use a telecommunications device for the deaf (TDD), call the 
Federal Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION: 

Executive Summary

    Species addressed. Oenothera californica ssp. eurekensis (Eureka 
Valley evening-primrose) and Swallenia alexandrae (Eureka dune grass) 
are endemic to three dune systems in the Eureka Valley, Inyo County, 
California. Eureka Valley falls within federally designated wilderness 
within Death Valley National Park and is managed accordingly by the 
National Park Service (Park Service).
    Why we need to publish this document. A species that is in danger 
of extinction or likely to become so in the foreseeable future 
throughout all or a significant portion of its range warrants 
protection under the Endangered Species Act. If a species is determined 
to no longer to be a threatened species or an endangered species, we 
may reclassify the species or remove it from the Federal List of 
Endangered and Threatened Wildlife and Plants. Removing a species from 
the List or changing its status on the List can only be completed by 
issuing a rule. We proposed to delist Eureka Valley evening-primrose 
and Eureka dune grass in 2014.
     This document finalizes the delisting of Eureka Valley 
evening-primrose. Our evaluation took into consideration information 
and comments submitted during the public comment period, as well as 
subsequent information that became available. At this time, the best 
available information continues to indicate that there are no longer 
population- or rangewide-level threats impacting Eureka Valley evening-
primrose such that it is in danger of extinction now or is likely to 
become endangered in the foreseeable future. Thus, we conclude that 
Eureka Valley evening-primrose no longer meets the definition of an 
endangered species or threatened species, and we are removing it from 
the Federal List of Endangered and Threatened Plants in title 50 of the 
Code of Federal Regulations at 50 CFR 17.12(h).
     This document finalizes the reclassification of Eureka 
dune grass from an endangered species to a threatened species. Based on 
our evaluation of the best scientific and commercial information 
available, including information and comments submitted during the 
public comment period, we now determine that the stressors identified 
in the proposed rule are more significant than previously thought. 
Although threats identified at the time of listing have been 
substantially removed, Eureka dune grass is currently responding 
negatively to the stressors to which it is exposed. The best available 
scientific and commercial data lead us to conclude that Eureka dune 
grass no longer meets the definition of an endangered species under the 
Act, but it is likely to become an endangered species within the 
foreseeable future throughout all or a significant portion of its 
range. Therefore, we are reclassifying the species from an endangered 
species to a threatened species.
    The basis for our action. Under the Endangered Species Act of 1973, 
a species may be determined to be an endangered species or threatened 
species because of any of 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. We must consider the same factors in 
delisting a species. We may delist a species if the best scientific and 
commercial data indicate the species is neither a threatened species 
nor an endangered species for one or more of the following reasons: (1) 
The species is extinct, (2) the species has recovered and is no longer 
endangered or threatened, or (3) the original scientific data used at 
the time the species was classified were in error.

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    We have determined that stressors to one or more populations of 
Eureka Valley evening-primrose no longer exist, or they are not causing 
significant impacts at either the population or rangewide scales such 
that the species is currently in danger of extinction or is likely to 
become endangered within the foreseeable future throughout all or a 
significant portion of its range. Additionally, we have determined that 
stressors to one or more populations of Eureka dune grass are of 
sufficient imminence, intensity, or magnitude to cause significant 
impacts at either the population or rangewide scales such that the 
species is likely to become an endangered species within the 
foreseeable future throughout all or a significant portion of its 
range.
    Peer review and public comment. We sought comments from independent 
specialists to ensure that our consideration of the status of Eureka 
Valley evening-primrose and Eureka dune grass is based on 
scientifically sound data, assumptions, and analyses. We invited these 
peer reviewers to comment on our proposed delisting rule. We also 
considered all public comments and information received during the 
comment period, and other new information available since publication 
of the proposed rule. The final decisions do not substantially rely on 
information received after the close of the comment period, as this new 
information was supportive of or consistent with information already in 
the record. Comments are addressed at the end of this Federal Register 
document.

Previous Federal Actions

    Please refer to the proposed delisting rule for Eureka Valley 
evening-primrose and Eureka dune grass (79 FR 11053, February, 27, 
2014) or the species' profiles available on the internet at 
www.ecos.fws.gov for a detailed description of the previous Federal 
actions concerning these species prior to the publication of the 
proposed delisting rule. The proposed delisting rule established a 60-
day comment period that closed on April 28, 2014, and we did not 
receive any requests to extend the comment period or hold a public 
hearing.

Background

    For the proposed delisting rule, we conducted a scientific analysis 
as presented in this document and supplemented with additional 
information presented in the Background Information document (Service 
2014, entire; available at http://www.regulations.gov, Docket No. FWS-
R8-ES-2013-0131). The Background Information document was prepared by 
Service biologists to provide additional discussion of the 
environmental setting for the Eureka Valley, and other information on 
the life history, taxonomy, genetics, seed bank ecology, survivorship 
and demography, rangewide distribution, and abundance surveys, as well 
as additional information on the stressors that may be impacting Eureka 
Valley evening-primrose and Eureka dune grass. Also, see the Final 
Species Analysis available under Docket No. FWS-R8-ES-2013-0131 at 
http://www.regulations.gov (Service 2017).

Eureka Dune Ecosystem

    Eureka Valley evening-primrose and Eureka dune grass are endemic 
(unique to a geographic area) to the sand dunes of Eureka Valley 
(Figure 1), which occur within Death Valley National Park, Inyo County, 
California. Three dune systems (collectively referred to as ``the 
Eureka Dunes'') occur in Eureka Valley and are located between the Last 
Chance Mountains to the east, the Saline Mountains to the south, and 
the Inyo Mountains to the west and north (Rowlands 1982, p. 2). The 
Main Dunes (sometimes referred to in literature as ``Eureka Dunes'') 
system parallel the Last Chance Mountains (Service 1982, p. 12) and are 
the largest of the three dunes, covering a total area of about 2,003 
acres (ac) (811 hectares (ha)) (Service 2013 based on Shovik 2010). The 
Saline Spur and Marble Canyon Dunes, two smaller dune systems, cover an 
area of about 238 ac (96 ha) and 610 ac (247 ha), respectively (Service 
2013 based on Shovik 2010). Saline Spur Dunes and Marble Canyon Dunes, 
including a southern extension of Marble Canyon Dunes known as the 
unnamed site, are located approximately 4 miles (mi) (6.4 kilometers 
(km)) and 9 mi (14.4 km) west of the Main Dunes (Bagley 1986, p. 4). 
The southern extension of Marble Canyon Dunes (the unnamed site) was 
previously treated as a separate dune system, but we refer to this area 
and the rest of the dune system as the Marble Canyon Dunes. See 
additional discussion in Service 2014 (pp. 4-7). Temperature regime, 
wind speeds, and precipitation patterns vary among the three dunes 
likely due to their relative position within Eureka Valley. For 
instance, the Main Dunes (labeled as ``Eureka Dunes'' in Figure 1, 
below) has lower daily temperatures than the other two dunes, while 
other patterns, such as rainfall, vary among the three dunes on both a 
temporal and spatial scale (Scoles-Sciulla and DeFalco 2017).

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[GRAPHIC] [TIFF OMITTED] TR27FE18.000

Eureka Valley Evening-Primrose

    See the proposed delisting rule (79 FR 11053) and the Background 
Information document (Service 2014) for a detailed discussion of Eureka 
Valley evening-primrose's description, taxonomy, life history, 
rangewide distribution, abundance surveys, and population estimates, 
which are available under Docket No. FWS-R8-ES-2013-0131 at http://www.regulations.gov.
    Eureka Valley evening-primrose is a short-lived perennial in the 
evening-primrose family (Onagraceae). It forms leaf rosettes for the 
first 1 or 2 years, then develops decumbent or ascending stems to 31.5 
inches (in) (8 decimeters) high. Large individuals have the potential 
to produce tens of thousands of seeds (Pavlik and Barbour 1985, pp. 15, 
21). Eureka Valley evening-primrose has mechanisms for both short- and 
long-distance seed dispersal (Pavlik 1979a, p. 59; 1979b, p. 71; Pavlik 
and Barbour 1985, pp. 27, 41; 1986, pp. 31, 81). Oenothera californica 
ssp. eurekensis is currently the accepted scientific name (Wagner 1993, 
p. 803; Wagner 2002, p. 395; Wagner et al. 2007, p. 180; Wagner 2012, 
p. 952; California Native Plant Society (CNPS) 2013). We have no 
specific information for Eureka Valley evening-primrose indicating the 
level of genetic diversity within or among the populations.
    In general, Eureka Valley evening-primrose individuals spend most 
of the year as a small rosette of leaves (Pavlik 1979a, pp. 47-49, 52; 
1979b, pp. 87-88). However, observations indicate that, under optimal 
conditions, recruits (first-year plants) can bloom in the year in which 
they germinate (Pavlik 1979a, p. 66). In April and May, mature plants 
undergo rapid stem elongation and bloom between April and July. Plants 
sometimes bloom again in the fall with additional summer or fall rains 
(Pavlik 1979a, p. 53; 1979b, p. 89). However, abundance and timing of 
rainfall appear to be important not only for germination, but for 
successful recruitment of individuals into the population; sufficient 
rainfall for germination in the fall months needs to be followed by 
additional rainfall events during the winter months for recruitment to 
occur (Pavlik and Barbour 1986, p. 10).
    In addition to the production of seed through sexual reproduction, 
Eureka Valley evening-primrose reproduces vegetatively through the 
production of clonal rosettes that arise from a branched rootstock 
(Pavlik 1979a, p. 68; Pavlik and Barbour 1986, p. 84; Pavlik and 
Barbour 1988, p. 240). If conditions are favorable, a large individual 
can produce both rosettes and flower in the same year. In years with 
unfavorable climatic conditions, established plants may remain dormant 
and persist underground by their fleshy roots. Therefore, the number of 
above-ground plants observed in any year represents only a portion of 
the population and may consist of multiple individuals of the same 
genetic identity.
    In general, evening-primrose taxa are pollinated by hawkmoths, 
butterflies, and bees (Gregory 1964, pp. 387, 398, 403, 407; Moldenke 
1976, pp. 322, 346, 358). In particular, a hawkmoth known as the white-
lined sphinx moth (Hyles lineata), bees (Haprobroda spp. (no common 
name), Hesperapis spp. (no common name)), and sweat bees (Lasioglossum 
lusoria) have been

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observed on Eureka Valley evening-primrose (Griswold in litt. 2012).
    New information made available during the comment period or since 
publication of the proposed rule is summarized in the next three 
sections below.
Species Description, Taxonomy, and Life History
    New information comprises the following: Over two growing seasons 
(2014, 2015), rooting depth for Eureka Valley evening-primrose was 
observed to be within the top 11.8 in (30 centimeters (cm)) of 
substrate (Scoles-Sciulla and DeFalco 2016, p. 9); compared to Eureka 
dune grass, which roots at a deeper level, Eureka Valley evening-
primrose accesses water that is closer to the surface of the sand. 
Additionally, Eureka Valley evening-primrose seeds buried in all three 
dunes in July of 2014 and retrieved after 3, 6, 9, and 14 months had 
high germination rates, regardless of burial depth or which dune they 
were buried at. By comparison, seeds that were stored indoors starting 
July 2014 had lower total germination after 3 and 6 months, but had 
similar total germination after 14 months (Scoles-Sciulla and DeFalco 
2016, p. 8). Overall, this information suggests that exposure to high 
temperatures during the summer months facilitates after-ripening (the 
period of internal change that is necessary in some apparently mature 
seeds before germination can occur) in this species (Scoles-Sciulla and 
DeFalco 2016, p. 8).
Rangewide Distribution
    New information comprises the following: Continued monitoring for 
visible presence/absence within the rangewide 1-ha grid system resulted 
in documentation of the largest expanse of Eureka Valley evening-
primrose ever recorded at all three dune systems since this monitoring 
effort began in 2007 (Park Service 2015). While the taxon remains tied 
to the sandy soils associated with the three dune systems, in ``good'' 
years such as 2014, individuals may be found farther away from the 
three dunes (Park Service 2014); however, the areas closer to the dunes 
continue to be the ``core'' areas where the taxon is found, even in 
years of lower abundance and productivity (Park Service 2013a, 2014, 
2015). This information indicates that Eureka Valley evening-primrose 
has the ability to withstand years of less-than-favorable climatic 
conditions, and take advantage of years with more favorable climatic 
conditions.
Abundance Surveys and Population Estimates
    New information comprises the following: Based on two additional 
years (2014, 2015) of monitoring Eureka Valley evening-primrose beyond 
the 2008-2013 monitoring period described in the proposed rule, the 
Park Service has continued to observe great annual variability in the 
abundance of the taxon, with 2014 being a ``superbloom'' year with the 
number of individuals estimated at well over 1 million (Park Service 
2014, p. 6). In 2015, the abundance was not as large as in 2014, but 
larger than it had been other years previous to 2014; based on Park 
Service data, we estimated the visible abundance to be in the tens of 
thousands (see Park Service 2015, Figure 12 on p. 16). Overall, this 
information suggests that the visible abundance is only a portion of 
the total number of individuals that are present from year to year 
(with other individuals remaining dormant if climatic conditions are 
less than optimal), and that this characteristic contributes to the 
resiliency of the species.

Eureka Dune Grass

    See the proposed delisting rule (79 FR 11053) and the Background 
Information document (Service 2014) for a detailed discussion of Eureka 
dune grass's description, taxonomy, life history, rangewide 
distribution, abundance surveys, and population estimates, which are 
available under Docket No. FWS-R8-ES-2013-0131 at http://www.regulations.gov.
    Eureka dune grass is a perennial, hummock-forming (development of 
mounds of windblown soil at the base of plants on dune landscapes) 
grass comprising a monotypic genus (genus containing only one single 
species) of the grass family (Poaceae). The coarse, stiff stems reach 
20 in (50 cm) in height, and the lanceolate leaves are tipped with a 
sharp point (DeDecker 1987, p. 2). Flowers are clustered in spike-like 
panicles and produce seeds that are 0.16 in (4 millimeter (mm)) long 
and 0.08 in (2 mm) wide (Bell and Smith 2012, p. 1,496). The root 
system becomes fibrous and extensive over time and can give rise to 
adventitious stems. Based on its morphological characteristics and 
taxonomic affinities, the species is thought to be a relictual species, 
which exists as a remnant of a formerly widely distributed group in an 
environment that is now different from where it originated.
    Eureka dune grass is dormant during the winter and begins to 
produce new shoot growth around February. Growth accelerates in May, 
with flowering from April to June and seed dispersal between May and 
July (Pavlik 1979a, pp. 47-49; Pavlik 1979b, p. 87; Service 1982, pp. 
4-6). Like all grass taxa, the flowers of Eureka dune grass are wind-
pollinated and, therefore, do not rely on insect pollinators. Eureka 
dune grass does not appear to propagate asexually (Pavlik and Barbour 
1985, p. 4); therefore, sexual reproduction is considered to be the 
dominant form of reproduction for this species.
    Individuals have been observed to continue growing for at least 12 
years with no signs of senescence (Henry n.d., pers. comm. in Pavlik 
and Barbour 1986, p. 11), and likely can grow for decades; older 
individuals form large hummocks that can reach on the order of 2,500 
cubic decimeters (88 cubic feet; extrapolated from Pavlik and Barbour 
(1988, p. 229)). Germination of new individuals appears to occur 
infrequently, typically in response to rainfall during the summer 
months (Pavlik and Barbour 1986, pp. 47-59).
    The amount of Eureka dune grass seed produced per individual 
increases with canopy size, which means that larger individuals may 
contribute more seed to the seed bank (Pavlik and Barbour 1985, p. 14). 
Compared to other perennial grass species, Eureka dune grass produces 
low numbers of seeds per individual (Pavlik and Barbour 1986, p. 30); 
this low seed production could be due to the inefficiency of wind 
pollination and the low density of individuals across the dunes (Pavlik 
and Barbour 1985, p. 17).
    New information made available during the comment period or since 
publication of the proposed rule is summarized in the next three 
sections below.
Species Description, Taxonomy, and Life History
    New information comprises the following: Over two growing seasons 
(2014, 2015), rooting depth for Eureka dune grass was observed to be 
35.4 in (90 cm) (Scoles-Sciulla and DeFalco 2016, p. 9).
Rangewide Distribution
    New information comprises the following:
    (1) In 2014 and 2015, the Park Service continued to monitor 
presence/absence of Eureka dune grass across all three dunes. Comparing 
the area (i.e., number of acres/hectares) that contained Eureka dune 
grass in 2015 with the area that contained Eureka dune grass in 2011, 
they found: On the Main Dunes, there was a 20 percent loss (from 1,102 
to 885

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ac (446 to 358 ha)); on Marble Canyon Dunes, there was a 1 percent loss 
(from 195 to 193 ac (79 to 78 ha)); and on Saline Spur Dunes, there was 
a 7 percent gain (from 215 to 230 ac (87 to 93 ha)) (Park Service 2015 
p. 5).
    (2) Since 2012, the Park Service has continued to map individual 
clumps of Eureka dune grass on the Main Dunes with Global Positioning 
System (GPS) (National Park Service 2015). Due to inconsistent 
application of mapping protocols in earlier years, the Park Service 
considers data from 2014 and 2015 to be the most accurate. From 2014 to 
2015, the area covered with dune grass declined by 19.2 percent (from 
69.39 to 56.05 ac (280,799 square meter (m\2\) to 226,846 m\2\)) (Park 
Service 2015). The greatest losses appear to be in the central and 
south-central portions of the Main Dunes.
    (3) Photopoints continued to be monitored by the Park Service in 
2014 and 2015. These photopoints, including some that were established 
in 1974, provide a qualitative assessment of the changes in coverage of 
Eureka dune grass within the viewsheds they include. For the Main 
Dunes, the combined viewshed of all photopoints represents 33.4 percent 
of the dune; for Marble Canyon Dunes, the combined viewshed represents 
21 percent of the dune; all photopoints from these two dunes document a 
substantial loss of Eureka dune grass coverage since the time they were 
established (Park Service 2014). The Park Service also noted that 
between 2014 and 2015, no substantial change was observed (Park Service 
2015), suggesting that the losses occurred prior to 2014. Photopoints 
were not established on the Saline Spur Dunes until 2008 and 2010 (Park 
Service 2014); therefore, data is not available for a long-term 
qualitative evaluation of dune grass coverage in this population.
    While a reduction in visible Eureka dune grass individuals is 
clearly noticeable from a visual inspection, it is difficult to 
quantify this reduction in terms of estimating changes in population 
distribution, densities, or abundance. Without other quantitative data 
to assist in interpretation, it would be difficult to distinguish 
whether visual changes represent local shifts in distribution and 
density or rangewide changes in the population. The additional 
information provided by the presence/absence monitoring, as well as the 
GPS mapping of clumps on the Main Dunes corroborates the observations 
of the loss of Eureka dune grass that has occurred over the last 35 
years.
    The most robust analysis can be made for the Main Dunes, for which 
there are all three sets of data (photopoints, presence/absence 
surveys, and GPS mapping), and all of which show a loss of individuals 
over time. The Main Dunes also represents over half of all the Eureka 
dune grass in Eureka Valley, so the loss from this dune is significant 
for the entire range of the species. Three sets of data (photopoints, 
presence/absence surveys, and GPS mapping), are also available for 
Marble Canyon Dunes, though presence/absence surveys and GPS mapping 
were initiated in both cases a year later than at the Main Dunes. 
Photopoints taken in the northern and northeastern portion of the dune 
show a loss of individuals between 1985 and 2013; presence/absence 
surveys indicate slight gains and losses between 2008 and 2015; and GPS 
mapping was not considered accurate by the Park Service until 2015, and 
therefore comparisons with earlier years cannot be made. Photopoint 
monitoring from the Main Dunes and from Marble Canyon Dunes both 
qualitatively indicate that extensive losses of dune grass occurred 
during the earlier portion of the 28-year monitoring period. More 
frequent photopoint monitoring was not initiated until 2007; by this 
time, most of the loss had already occurred, and more recent photos 
show less change.
    Only presence/absence surveys (initiated in 2008) and GPS mapping 
of individuals (initiated in 2012 but not considered accurate until 
2015) is available for Saline Spur Dunes. These two data sets have 
established that the western edge of Saline Spur Dunes contains the 
largest continuous population of Eureka dune grass at all three dunes 
(Park Service 2015 p. 2). Photopoint monitoring at this dune was only 
established in 2008 and 2010, and as of 2014 did not indicate any 
visible change (Park Service 2014, p. 6).
    On a small scale, the usefulness of comparing recent maps with 
historical maps is limited because of the higher precision that was 
possible in the 2007 to 2015 surveys. Overall and on a large scale, the 
most recent maps indicate that Eureka dune grass populations are still 
present in the same general locations from which they were known at the 
time of our 2007 5-year status review. The precision that has been 
available with the hectare grid surveys and the GPS mapping has 
provided more useful examination of the distribution of Eureka dune 
grass on a smaller scale and a means by which to compare changes in 
distribution over time. The total extent of Eureka dune grass on all 
three dunes as of 2015 (Park Service 2015) is presented in the 
``Swallenia Maps'' document available on the internet at http://www.regulations.gov under Docket No. FWS-R8-ES-2013-0131.
Abundance Surveys and Population Estimates
    For a detailed discussion of the abundance and population estimates 
for Eureka dune grass, see the Background Information Document (Service 
2014), which is available under Docket No. FWS-R8-ES-2013-0131 at 
http://www.regulations.gov. In that previous discussion, we stated that 
developing population estimates for Eureka dune grass is challenging 
because of: Lack of historical information regarding population sizes 
at the time of listing (to establish baseline for comparison), the 
site-specific transects that were done in 1976 and 1986 (e.g., see 
Henry (1976) and Bagley (1986)), and followup surveys conducted by the 
Park Service (Park Service 2008a, pp. 5-6 and 17-18), were too 
spatially limited to be useful for population estimates, and estimating 
numbers of individuals is inherently difficult because of their 
clumping growth form. The Park Service previously attempted estimating 
population size based on the monitoring of the hectare grid at all 
three dunes: For the year 2011, the estimate was 8,014 individuals, and 
for 2013, it was 8,176 individuals (Park Service 2013a, p. 7). The Park 
Service cautions that the true population size could vary greatly due 
to a variety of limitations and assumptions. Even so, we know that, 
based on this information, thousands of Eureka dune grass individuals 
exist, and the number was relatively stable across the 2 years 
compared.
    New information comprises the following: The Park Service has not 
attempted a revised method for estimating population size due to the 
inherent difficulty of doing so. However, because the estimates were 
based on the area occupied by Eureka dune grass in the monitoring of 
the hectare grid, we refer back to that metric (see section on 
Rangewide Distribution for Eureka dune grass, above) as a surrogate.
    The best available data indicate the species continues to occur 
within Eureka Valley at all three dunes within its range (and as stated 
above, we have no information regarding population size at the time of 
listing for comparison, with population surveys prior to listing being 
limited to the northern end of the Main Dunes). Based on the 
combination of all data available (photopoints monitoring, presence/
absence surveys based on the hectare grid, and GPS mapping of 
individual clumps), indications are that, between

[[Page 8581]]

2011 and 2015, the amount of Eureka dune grass has declined at the Main 
Dunes by 20 percent; the changes at Marble Canyon Dunes and Saline Spur 
Dunes have been of a smaller magnitude, with Marble Canyon Dunes 
showing a one percent loss, and with Saline Spur Dunes showing a seven 
percent increase (Park Service 2015, p. 5).

History of Threats Analyses for Eureka Valley Evening-Primrose and 
Eureka Dune Grass

    For a brief history of the threats analyses that we conducted since 
the time Eureka Valley evening-primrose and Eureka dune grass were 
listed in 1978, see our proposed delisting rule (79 FR 11053, February 
27, 2014). For a detailed discussion of the status review initiated 
with our 2011 90-day finding (76 FR 3069, January 19, 2011), see the 
Background Information document (Service 2014, pp. 38-65). Both the 
proposed listing rule and Background Information document are available 
on the internet at http://www.regulations.gov at Docket No. FWS-R8-ES-
2013-0131.

Summary of Changes From the Proposed Rule

    (1) We updated information on annual survey results based on 
monitoring for abundance and distribution undertaken by the Park 
Service in 2014 and 2015 (Park Service 2014, 2015). Also included is 
the Park Service's new subsampling methodology (Park Service 2017).
    (2) We updated information on abiotic characteristics of the dune 
habitat (temperature, wind, and precipitation patterns) within the 
description of the Eureka Dunes Ecosystem in the Background section 
based on observations made by the United States Geological Survey 
(USGS) (Scoles-Sciulla and DeFalco 2017).
    (3) We updated information on life-history characteristics, 
specifically rooting depth, for both species, and seed longevity for 
Eureka Valley evening-primrose, based on observations made by USGS 
(Scoles-Sciulla and DeFalco 2017).
    (4) We added new information to the section on potential 
competition between Salsola spp. (Russian thistle) and Eureka Valley 
evening-primrose, based on research conducted by Chow (2016).
    (5) On July 1, 2014, we published a final policy interpreting the 
phrase ``significant portion of its range'' (79 FR 37578). We have 
revised our discussion of ``significant portion of its range'' as it 
relates to both Eureka Valley evening-primrose and Eureka dune grass in 
the Determinations section below to be consistent with our policy. 
Although the final policy's approach differed slightly from that 
discussed in the proposed rule, applying the policy did not affect the 
outcome of the final status determinations.
    (6) We have revised our determination regarding Eureka dune grass 
based on new information and analyses, and now conclude it best fits 
the definition of a threatened species.

Recovery and Recovery Plan Implementation

    Section 4(f) of the Act directs us to develop and implement 
recovery plans for the conservation and survival of endangered and 
threatened species unless we determine that such a plan will not 
promote the conservation of the species. Under section 4(f)(1)(B)(ii), 
recovery plans must, to the maximum extent practicable, include: 
``Objective, measurable criteria which, when met, would result in a 
determination, in accordance with the provisions of [section 4 of the 
Act], that the species be removed from the list.'' However, revisions 
to the list (adding, removing, or reclassifying a species) must reflect 
determinations made in accordance with sections 4(a)(1) and 4(b) of the 
Act. Section 4(a)(1) requires that the Secretary determine whether a 
species is an endangered species or threatened species (or not) because 
of one or more of five threat factors. Section 4(b) of the Act requires 
that the determination be made ``solely on the basis of the best 
scientific and commercial data available.'' Therefore, recovery 
criteria should help indicate when we would anticipate that an analysis 
of the species' status under section 4(a)(1) would result in a 
determination that the species is no longer an endangered species or 
threatened species.
    Thus, while recovery plans provide important guidance to the 
Service, States, and other partners on methods of minimizing threats to 
listed species and measurable objectives against which to measure 
progress towards recovery, they are not regulatory documents and cannot 
substitute for the determinations and promulgation of regulations 
required under section 4(a)(1) of the Act. A decision to revise the 
status of or remove a species from the Federal List of Endangered and 
Threatened Plants (50 CFR 17.12) is ultimately based on an analysis of 
the best scientific and commercial data then available to determine 
whether a species is no longer an endangered species or a threatened 
species, regardless of whether that information differs from the 
recovery plan. Below, we summarize the recovery plan goals and discuss 
progress toward meeting the recovery objectives and how they inform our 
analyses of the species' status and the stressors affecting them.
    In 1982, we finalized the Eureka Valley Dunes Recovery Plan, which 
included recovery objectives for both Eureka Valley evening-primrose 
and Eureka dune grass (Recovery Plan; Service 1982). While the Recovery 
Plan did not include recovery criteria, the plan followed guidance in 
effect at the time it was finalized and we consider its recovery 
objectives to be similar to what are considered to be recovery criteria 
under current recovery planning guidance. The Recovery Plan identified 
two objectives, each with specific recovery tasks, to consider Eureka 
Valley evening-primrose and Eureka dune grass for downlisting to 
threatened status, and eventually, delisting (Service 1982, pp. 26-41). 
These two objectives are:
    (1) Restore the Eureka dune grass and the Eureka Valley evening-
primrose to threatened status by protecting extant populations from 
existing (i.e., in 1982) and potential human threats.
    (2) Determine the number of individuals, populations, and acres of 
habitat necessary for each species to maintain itself without intensive 
management, in a vigorous, self-sustaining manner within their natural 
historical dune habitat (estimated 6,000 ac (2,428 ha)) and implement 
recovery tasks to attain these objectives.
    Objective 1: Restore the Eureka dune grass and the Eureka Valley 
evening-primrose to threatened status by protecting extant populations 
from existing (i.e., in 1982) and potential human threats.
    Objective 1 is intended to remove existing human threats to 
populations of Eureka Valley evening-primrose and Eureka dune grass 
through enforcement of existing laws and regulations, and management of 
human access to Eureka Valley (Service 1982, p. 26). At the time of 
listing, the primary threat to both species was off-highway vehicle 
(OHV) activity, and a lesser threat was camping on and around the dunes 
(43 FR 17910, April 26, 1978). Since listing, potential human threats 
have included other recreational activities such as sandboarding and 
horseback riding.
    Various land management decisions and activities have been 
implemented by the Bureau of Land Management (BLM; prior to Park 
Service acquisition of the Eureka Valley area in 1994) and the Park 
Service (since 1994). All of the dune systems within Eureka Valley have 
also been designated as Federal

[[Page 8582]]

wilderness areas. A number of land use decisions and management 
activities have been implemented to support the long-term protection of 
Eureka Valley evening-primrose and Eureka dune grass within the Federal 
wilderness area, including (but not limited to): Making OHV activity 
illegal; conducting patrols to enforce laws, regulations, and 
restrictions; closing and restoring unauthorized roads; installing 
interpretative signs, barriers, and wilderness boundary signs; and 
delineating and maintaining campsites (Park Service 2008a, 2009, 2010).
    Additionally, various education and public outreach (e.g., public 
awareness program, interpretive displays) have been conducted to reduce 
overall impacts to both species. Because all three populations occur 
within Federal wilderness areas that are now protected against the 
threats identified as imminent at the time of listing and in the 
Recovery Plan, we conclude that the condition of the habitat for Eureka 
Valley evening-primrose and Eureka dune grass has improved due to 
management activities that have been implemented by BLM and the Park 
Service, and that this recovery objective has been met.
    Objective 2: Determine the number of individuals, populations, and 
acres of habitat necessary for each species to maintain itself without 
intensive management, in a vigorous, self-sustaining manner within 
their natural historical dune habitat (estimated 6,000 ac (2,428 ha)) 
and implement recovery tasks to attain these objectives.
    At the time the recovery plan was developed, our knowledge of the 
demographic characteristics of the two species was limited. The intent 
of this objective was to gather and develop information necessary to 
evaluate the status of both species with regards to demographic 
characteristics to determine at what point they could be considered 
recovered, and more importantly to attain the desired demographic 
levels necessary for recovery. While we have not yet developed precise 
values for all of the various demographic characteristics that help us 
determine whether actions to remove threats have the desired effect 
(e.g., stable populations, positive growth), both species still occupy 
all three dune systems, and the best available monitoring data indicate 
thousands of plants are present at each dune system. Additionally, the 
best available information indicates that the BLM and Park Service have 
sufficiently minimized OHV and other recreation activities that were 
previously impacting the populations and their habitat. Even though the 
precise values of all demographic characteristics are not known, we 
note that many research and monitoring efforts have occurred for both 
species since the time of listing (unless otherwise noted), which have 
provided information on the life-history needs of both Eureka Valley 
evening-primrose and Eureka dune grass, as well as potential impacts to 
both species, including (but not limited to) the following studies:
    (1) Conducting a series of studies on both species to investigate 
effects of pollination on seed set, seed ecology, species' demography, 
and plant and animal interactions (herbivory, seed predation, and 
dispersal) (Pavlik and Barbour 1985, 1986).
    (2) Establishing baseline conditions for monitoring trends of both 
species across all three dune systems (Bagley 1986).
    (3) Studying the genetic diversity of all Eureka dune grass 
populations (Bell 2003).
    (4) Conducting partial distribution surveys of both species on 
portions of various dunes (Beymer in litt. 1997; Peterson in litt. 
1998), as well as documenting the distribution and abundance of Russian 
thistle, a potential competitor, across all three dune systems (Park 
Service 2011a).
    (5) Documenting distribution, abundance, and demography of both 
species (Park Service 2008b, 2008c, 2010a, 2011a, 2011b, 2012, 2013a, 
2014, 2015, 2017).
    (6) Determining if vegetation succession at the northern end of the 
Main Dunes (Eureka dune grass habitat) is associated with changes in 
subsurface hydrology (Park Service 2008c, p. 4).
    (7) Investigating potential competition between Russian thistle and 
Eureka Valley evening-primrose, and the effects of herbivory on Eureka 
Valley evening-primrose (Chow and Klinger 2013a; Chow in litt. 2011; 
Chow 2016).
    (8) Monitoring photopoint stations over time, starting in 1985, and 
retaken at various intervals (Park Service 2008c, 2011b, 2014).
    (9) Investigating the correlations between abiotic factors 
(temperature, wind, and precipitation patterns) and growth response in 
Eureka Valley evening-primrose and Eureka dune grass (Scoles-Sciulla 
and DeFalco 2017).
    As a result of the considerable work that has been undertaken to 
understand the population dynamics and life histories of these two 
species, we have: (1) Established detailed baseline information 
regarding the abundance and distribution of both species with which to 
compare their status in future years, including the documentation of a 
population estimate for over a million individuals of Eureka Valley 
evening-primrose in the ``superbloom'' year of 2014; (2) investigated 
potential stressors more closely and determined that some potential 
stressors are of more concern than others; (3) clarified how the life-
history strategies of the two species are different and lead to 
resiliency for Eureka Valley evening-primrose but not Eureka dune 
grass; and (4) suggested other potential stressors for the two species 
that should be monitored into the future. Overall, we consider the 
intent of Objective 2 has been partially met.
    In summary, based on our review of the Recovery Plan and the 
information obtained from the various management activities, surveys, 
and research that have occurred to date, we conclude that the habitat 
for Eureka Valley evening-primrose and Eureka dune grass has been 
protected and its status improved due to land use decisions and 
management activities that have been implemented by BLM and the Park 
Service to reduce human-caused threats (Objective 1). Further, we 
conclude, as detailed below, that the status of Eureka Valley evening-
primrose has improved substantially as documented by its resiliency and 
elucidated by the surveys and research undertaken since the time of 
listing (Objective 2). Therefore, the intent of both objectives has 
been met for the Eureka Valley evening-primrose. However, Objective 2 
has not been met for the Eureka dune grass because monitoring data 
indicate declining trends at the Main Dunes and Marble Canyon Dunes.

Summary of Factors Affecting the Species

    Section 4 of the Act and its implementing regulations (50 CFR part 
424) set forth the procedures for listing species, reclassifying 
species, or removing species from listed status. ``Species'' is defined 
by the Act as including any species or subspecies of fish or wildlife 
or plants, and any distinct population segment of any species of 
vertebrate fish or wildlife which interbreeds when mature (16 U.S.C. 
1532(16)). A species may be determined to be an endangered or 
threatened species because of any one or a combination of the five 
factors described in section 4(a)(1) of the Act: (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

[[Page 8583]]

human made factors affecting its continued existence. A species may be 
reclassified or removed from the Federal List of Endangered and 
Threatened Plants (50 CFR 17.12) on the same basis.
    Determining whether the status of a species has improved to the 
point that it can be downlisted or delisted requires consideration of 
whether the species is an endangered species or threatened species 
because of the same five categories of threats specified in section 
4(a)(1) of the Act. For species that are already listed as endangered 
species or threatened species, this analysis of threats is an 
evaluation of both the threats currently facing the species and the 
threats that are reasonably likely to affect the species in the 
foreseeable future following the delisting or downlisting and the 
removal or reduction of the Act's protections.
    A species is an ``endangered species'' for purposes of the Act if 
it is in danger of extinction throughout all or a significant portion 
of its range and is a ``threatened species'' if it is likely to become 
an endangered species within the foreseeable future throughout all or a 
significant portion of its range. The word ``range'' in the significant 
portion of its range phrase refers to the range in which the species 
currently exists, and the word ``significant'' refers to the value of 
that portion of the range being considered to the conservation of the 
species. The ``foreseeable future'' is the period of time over which 
events or effects reasonably can or should be anticipated, or trends 
extrapolated. For the purposes of this analysis, we first evaluate the 
status of the species throughout all its range, then consider whether 
the species is in danger of extinction or likely to become so in a 
significant portion of its range.

Summary of Factors Affecting Eureka Valley Evening-Primrose

A. The Present or Threatened Destruction, Modification, or Curtailment 
of Its Habitat or Range
OHV Activity
    For a detailed discussion of the types and amount of OHV activity, 
both at the time of listing and since then, see the proposed delisting 
rule (79 FR 11053, February 27, 2014) and the Background Information 
document (Service 2014), which are available under Docket No. FWS-R8-
ES-2013-0131 at http://www.regulations.gov. OHV activity has not been 
authorized on the dunes in Eureka Valley since 1976, and not anywhere 
off established roads since 1994, when all the lands in Eureka Valley 
were included in a wilderness area designation.
    OHV activity could affect Eureka Valley evening-primrose habitat in 
multiple ways, as evidenced from many studies that have occurred within 
dune ecosystems (such as Wilshire and Nakata 1976, Webb and Wilshire 
1983). Physical impacts on dunes can include compaction or erosion of 
sandy substrates, acceleration of wind erosion (Gillette and Adams 
1983, pp. 97-109), and acceleration of dune drift (Gilberston 1983, pp. 
362-365). OHV activity can also change the unique hydrologic conditions 
of dunes. Because dunes have the capacity to hold moisture for long 
periods of time, disturbance of the surface sands resulting in exposure 
of moist sands underneath can increase moisture loss from the dunes 
(Geological Society of America 1977, p. 4). Changes in physical and 
hydrologic properties of the dunes from heavy OHV activity could in 
turn affect the suitability of the dune habitat for germination and 
recruitment of seedlings, clonal expansion of existing individuals, and 
dispersal of seeds to favorable microsites.
    The same potential OHV impacts that affect dune habitat can also 
affect Eureka Valley evening-primrose individual plants. Normally, 
these types of impacts would be discussed under Factor E (Other Natural 
or Manmade Factors Affecting Its Continued Existence), but are included 
here in the Factor A discussion for ease of analysis. OHV impacts to 
individual plants within dune systems and other desert ecosystems have 
been extensively studied (such as Bury and Luckenbach 1983, Gilbertson 
1983, and Lathrop 1983). Within dunes systems, for instance, while OHV 
activity alters the physical structure and hydrology of the dunes 
(rendering the dune habitat less suitable for supporting individuals 
and populations of the two species), it also affects individuals 
directly by shredding plants or damaging root systems, thereby killing 
or injuring (e.g., reducing the reproduction or survival of 
individuals) the plants.
    Although unauthorized OHV activity has occasionally occurred on the 
Eureka Dunes, it has not approached the levels seen prior to listing 
Eureka Valley evening-primrose as an endangered species. Existing 
regulatory mechanisms (such as through the Park Service's Organic Act 
and other laws guiding management of Park Service lands) in place since 
listing have resulted in beneficial effects to the species (e.g., 
management measures to control OHV and recreational activities) (see 
additional discussion under Factor D, below). The management of OHV 
activity through land use designations (i.e., Area of Critical 
Environmental Concern, Federal wilderness areas) has resulted in the 
near elimination of OHV activity on Eureka Dunes at the current time. 
We anticipate this situation will continue into the future because we 
expect Federal wilderness areas to remain in place indefinitely, and we 
expect the Park Service's current management to be implemented over the 
next 20 years, as well as modified periodically into the future with 
adaptive management strategies (as demonstrated by the Park Service's 
natural resource management strategies to date and anticipated in the 
future per Park Service policies and regulations (see Factor D)). 
Additionally, the remote location, inaccessibility, and wilderness 
status of the Saline Spur and Marble Canyon Dunes appear to be 
providing sufficient protection for dune habitats and plants at these 
locations both currently and in the future. Although the Park Service 
has documented sporadic occurrences of unauthorized OHV activity, these 
occurrences are almost entirely localized to areas on and adjacent to 
the northern end of the Main Dunes (Park Service 2013a, p. 3).
    In response to the publication of the proposed delisting rule, Park 
Service stated that OHV trespass on the dunes still occurs and is 
documented at least annually, and that current staffing and funding 
levels do not allow for a constant park presence at the dunes, which 
would be required to completely prevent OHV trespass (Park Service 
2014, p. 5). Regardless, the best available information indicates that 
OHV trespass activity is no longer causing significant population- or 
rangewide-level impacts to Eureka Valley evening-primrose.
Other Recreational Activities
    In addition to unauthorized OHV activity that may occur currently 
(as described above), other recreational activities have been known 
historically and currently occur (occasionally) within the Eureka 
Dunes, including horseback riding, sandboarding, camping outside of 
designated areas, and creation of access routes. For a detailed 
discussion regarding these recreational activities, both at the time of 
listing and since then, see the proposed delisting rule (79 FR 11053, 
February 27, 2014) and the Background Information document (Service 
2014), which are available under Docket No. FWS-R8-ES-2013-0131 at 
http://www.regulations.gov. Camping and associated access routes were 
identified as a minor threat in the Recovery Plan because their 
proximity to Eureka Dunes

[[Page 8584]]

facilitated unauthorized OHV activity (Service 1982, pp. 22-23). 
Horseback riding and sandboarding were potential threats to Eureka 
Valley evening-primrose and Eureka dune grass identified after listing, 
and were discussed in the 5-year status reviews published in 2007 
(Service 2007a, p. 10; Service 2007b, pp. 7-8). All of these activities 
were discussed in our 5-year review under Factor A because, like OHV 
activity, they have the ability to have physical impacts on the dune 
habitat (such as destabilization and displacement of sands); however, 
these same activities have the potential for damaging individual plants 
through crushing, trampling, and uprooting. Although impacts to 
individual plants are more appropriately discussed under Factor E, for 
ease of analysis we also discuss impacts to individual plants here.
    New information regarding impacts specifically to Eureka Valley 
evening-primrose individual plants (as opposed to habitat) comprises 
the following: In response to the publication of the proposed delisting 
rule, the Park Service referred back to a study conducted by Pavlik 
(1979a), which found that seedlings of both Eureka dune grass and 
Eureka Valley evening-primrose are extremely fragile and cannot 
tolerate even the lightest disturbance by foot traffic. Although the 
Park Service has not been able to measure the amount of foot traffic, 
the potential impacts from such traffic can be qualitatively observed 
on stabilized sand following rain events (Park Service 2014, p. 5). In 
addition, one peer reviewer observed evidence (i.e., tracks) of 
unauthorized OHV activity at the base of the Main Dunes, as well as 
increased visitor use, specifically camping, at the dunes since the 
1980s (McLaughlin in litt. 2014).
    Our current assessment is that, while the Park Service has 
documented some unauthorized activity (e.g., sandboarding, OHV activity 
in closed areas) that may result in minor or occasional impact to 
individual plants, these are infrequent occurrences and affect very 
small areas and are not spread throughout the range of the species. 
Additionally, existing regulatory mechanisms (such as through the Park 
Service's Organic Act and other laws guiding management of Park Service 
lands) in place since listing have resulted in beneficial effects to 
the species (including management measures to control recreational 
activities) (see additional discussion under Factor D, below). 
Therefore, the best available information at this time indicates that 
other recreational activities, if they occur, are not causing 
population-level effects (as compared to pre-listing levels) to Eureka 
Valley evening-primrose currently, nor are they expected to do so in 
the future, in large part due to the extensive protections and 
management provided by the Park Service.
    As discussed in the proposed rule (79 FR 11053, February 27, 2014), 
regulatory provisions of the Wilderness Act, the Park Service Organic 
Act, and the other laws guiding management of Park Service lands are 
adequate to minimize threats to populations of Eureka Valley evening-
primrose from OHV activity, sandboarding, and horseback riding.
B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes
    Utilization for commercial, recreational, scientific, or 
educational purposes was not identified as a threat to Eureka Valley 
evening-primrose in the listing rule. There is no known commercial or 
recreational value that we consider consumptive (that is, based on 
physical use or removal of the plants). Educational groups frequently 
visit Eureka Dunes, but we are unaware of any activities that would be 
considered consumptive use. Since listing, there have been three 
section 10(a)(1)(A) permits issued for studies involving the removal of 
plants, seeds, or plant parts; only two of these permits included 
Eureka Valley evening-primrose. These studies usually involve 
collection of seeds or leaves for laboratory experiments or collection 
of voucher specimens for herbaria; in each case we analyzed potential 
impacts during the permitting process and determined that the 
collection activities would not jeopardize the continued existence of 
the species. We do not consider this level of research and collection 
to pose any potential threat of overutilization for the species. 
Furthermore, the State of California and the Park Service have 
regulatory mechanisms in place to control any potential utilization in 
the future (see also Factor D below). Any collection of plants would 
require permits from the State of California and the Park Service. We 
do not have any new information regarding this factor, and we conclude 
that overutilization for commercial, recreational, scientific, or 
educational purposes are not a short-term or long-term threat to the 
continued existence of Eureka Valley evening-primrose.
C. Disease or Predation
    At the time of listing, disease and predation were not identified 
as a potential threat to Eureka Valley evening-primrose. Since then, 
studies (Pavlik and Barbour 1985, 1986; Scoles-Sciulla and DeFalco 
2013) and observations (Chow in litt. 2011, 2012b) imply that herbivory 
and seed predation may be a potential stressor for the species. For a 
detailed discussion regarding disease and predation, both at the time 
of listing and since then, see the proposed delisting rule (79 FR 
11053, February 27, 2014) and the Background Information document 
(Service 2014), which are available under Docket No. FWS-R8-ES-2013-
0131 at http://www.regulations.gov.
    New information comprises updated results from two studies that 
were ongoing at the time the proposed rule published.
    (1) Chow and Klinger (2014) evaluated the effects of lagomorph 
(taxonomic order of mammals comprising rabbits, hares, and pikas) 
herbivory on Eureka Valley evening-primrose competition, both with 
itself, and with Russian thistle (see discussion of the latter under 
Factor E) in an ex situ setting. While herbivory can result in the 
removal of aboveground vegetative material, it was not found to 
exacerbate intraspecific competition in Eureka Valley evening-primrose 
(Chow and Klinger (2013b, p. 21). However, herbivory can result in 
mortality of plants if individuals are repeatedly consumed or the roots 
are eaten, and it could also impact flower and fruit production (Chow 
and Klinger 2014, pp. 19, 21).
    (2) USGS (Scoles-Sciulla and DeFalco 2013) observed that up to 99 
percent of the surface area of Eureka Valley evening-primrose 
individuals were consumed over the growing season in 2012, contributing 
to low survival rates at all dune sites that year. In subsequent years, 
USGS reported on survival rates over the course of the growing season 
(e.g., 100 percent in 2013 (Scoles-Sciulla and DeFalco 2014, pp. 8-9), 
and between 20 and 70 percent at various dunes in 2014 (Scoles-Sciulla 
and DeFalco 2015, pp. 8-9); however, no other herbivory effects were 
discussed with the findings for these years.
    Seed predation and herbivory are naturally occurring processes. We 
expect that Eureka Valley evening-primrose has adapted to withstand 
some level of herbivory and seed predation. Given that Eureka Valley 
evening-primrose continues to occupy the same general distribution 
identified at the time of listing, it does not appear that herbivory 
and seed predation by themselves are occurring at such a level to cause 
population-level declines or other adverse effects to the species as a 
whole. Based on the best available

[[Page 8585]]

information at this time (including the research observations provided 
by Chow and Klinger (2013b) and USGS (Scoles-Sciulla and DeFalco 2014, 
2015); the expectation that this species has evolved with some level of 
herbivory/seed predation; and the fact that herbivory/seed predation is 
naturally occurring and some level of herbivory/seed predation is 
expected, we conclude that the observed impacts are not causing 
population-level effects for Eureka Valley evening-primrose currently, 
nor are they expected to do so in the future.
D. The Inadequacy of Existing Regulatory Mechanisms
    Under this factor, we evaluate whether the stressors identified 
within the other factors may be ameliorated or exacerbated by any 
existing regulatory mechanisms or conservation efforts. Section 
4(b)(1)(A) of the Act requires that the Service take into account 
``those efforts, if any, being made by any State or foreign nation, or 
any political subdivision of a State or foreign nation, to protect such 
species. . . .'' In relation to Factor D under the Act, we interpret 
this language to require the Service to consider relevant Federal, 
State, and Tribal laws, regulations, and other such binding legal 
mechanisms that may ameliorate or exacerbate any of the threats we 
describe in threat analyses under the other four factors or otherwise 
enhance the species' conservation. Our consideration of these 
mechanisms is described in detail within each of the threats or 
stressors to the species (see discussion under each of the other 
factors).
    The following existing regulatory mechanisms and conservation 
actions were specifically considered and discussed as they relate to 
the stressors, under the applicable factors, affecting Eureka Valley 
evening-primrose: The Wilderness Act, the Park Service Organic Act, and 
the other laws guiding management of Park Service lands are adequate to 
minimize threats to populations of Eureka Valley evening-primrose from 
OHV activity, sandboarding, and horseback riding. Beneficial effects 
for Eureka dune grass include: (1) Management measures to control 
illegal OHV activity (see Factor A discussion, above), including the 
Park Service's management policies (Park Service 2006); (2) the Organic 
Act; (3) the legal and stewardship mandates outlined in the Park 
Service's General Management Plan (Park Service 2002, entire); and (4) 
the Wilderness and Backcountry Stewardship Plan (Park Service 2013b, 
pp. 4, 5, 10, 16), given all areas containing populations of the 
species are within congressionally designated wilderness. The best 
available information indicates that these existing regulatory 
mechanisms have reduced the previously identified significant adverse 
effects to individual plants and populations, especially impacts 
associated with OHV activity (Factors A and E) and other recreational 
activities (i.e., sandboarding, camping, and associated access routes) 
(Factors A and E). There are no existing regulatory mechanisms to 
address other potential stressors, including herbivory, seed predation, 
competition with Russian thistle, effects of climate change, and 
stochastic events.
    While most of these laws, regulations, and policies are not 
specifically directed toward protection of Eureka Valley evening-
primrose, they mandate consideration, management, and protection of 
resources that benefit the species. We expect these laws, regulatory 
mechanisms, and management plans to remain in place into the future.
    For a detailed discussion regarding inadequacy of existing 
regulatory mechanisms, both at the time of listing and since then, see 
the proposed delisting rule (79 FR 11053, February 27, 2014) and the 
Background Information document (Service 2014), which are available 
under Docket No. FWS-R8-ES-2013-0131 at http://www.regulations.gov. 
There is no new information concerning these regulatory mechanisms.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
OHV Activity and Other Recreational Activities
    See the ``OHV Activity'' and ``Other Recreational Activities'' 
sections, above under Factor A, for a complete discussion of realized 
and potential impacts since the time of listing. As stated there, we 
included a complete discussion of potential impacts to both habitat and 
individual plants under Factor A for ease of analysis. We conclude, 
based on the best available information, that the Wilderness Area 
designation, coupled with Park Service management of OHV activity and 
other recreational activity, has significantly reduced potential 
impacts to Eureka Valley evening-primrose individuals, currently and 
into the future. See additional discussion above under Factors A and D.
Competition With Russian Thistle
    Invasive, nonnative plants can potentially affect the long-term 
persistence of endemic species. Salsola spp. (Russian thistle) is the 
only invasive, nonnative species that has spread onto the dunes in the 
Eureka Valley. Previous information (available at the time of our 2007 
5-year reviews) was generally limited to personal observations and 
collections with no specific information regarding the density or 
distribution of Russian thistle. However, due to continuing concerns 
expressed by the Park Service and other parties since 2007, we 
conducted a more thorough review of the life-history characteristics of 
Russian thistle and the potential impacts it could have on Eureka 
Valley evening-primrose, particularly the potential for Russian thistle 
to compete with Eureka Valley evening-primrose for resources such as 
water and nutrients, which would potentially result in fewer or smaller 
individuals of Eureka Valley evening-primrose. We also reviewed 
information provided by the Park Service concerning the distribution of 
Russian thistle on and around the dunes in Eureka Valley and 
preliminary results of an ex situ competition study (Chow and Klinger 
2013b). For a detailed discussion regarding the potential for 
competition between Eureka Valley evening-primrose and Russian thistle, 
both at the time of listing and since then, see the proposed delisting 
rule (79 FR 11053, February 27, 2014) and the Background Information 
document (Service 2014), which are available under Docket No. FWS-R8-
ES-2013-0131 at http://www.regulations.gov.
    New Information comprises the following: A preliminary study 
regarding interspecific competition (competition between individuals of 
different species) and intraspecific competition (competition between 
individuals of the same species) initiated in 2012 was updated by Chow 
and Klinger (2016) and Chow (2016). They found that competition 
(interspecific and intraspecific) reduced the relativized biomass of 
target individuals for both Eureka Valley evening-primrose and Russian 
thistle (Chow and Klinger 2014, p. 16). They were unable to determine 
if competition (inter- and intraspecific) affected the reproductive 
potential of either taxa, although they did observe that Eureka Valley 
evening-primrose produced more vegetative material, whereas Russian 
thistle produced more reproductive material (Chow and Klinger 2014, p. 
20). This is likely the result of the different reproductive strategies 
(annual versus perennial) employed by these two taxa (Chow and Klinger 
2014, p. 20). As in their preliminary study, Chow and Klinger (2013b, 
p. 16) found that Eureka

[[Page 8586]]

Valley evening-primrose tolerated interspecific competition better than 
Russian thistle. However, the effect of intraspecific competition 
between Eureka Valley evening-primrose individuals was less clear. For 
example, the highest number of neighbors (i.e., six individuals) in one 
of the treatments did not result in the greatest impact to the target 
individual (Chow and Klinger 2014, p. 16). This may be because of 
competition occurring below ground.
    Rooting depth of Eureka Valley evening-primrose was observed during 
the course of two different studies. Most of the Eureka Valley evening-
primrose roots examined from a laboratory experiment were located at 
the bottom of pots as opposed to Russian thistle roots, which were more 
concentrated in the mid-section of the pot (Chow and Klinger 2014, pp. 
17-18). This finding suggests the possibility that the spatial 
separation of the roots of Eureka Valley evening-primrose and Russian 
thistle is why the effects of intraspecific competition examined on the 
dunes was greater for Eureka Valley evening-primrose than interspecific 
competition. Rooting depth relative to soil moisture was also observed 
by USGS (Scoles-Sciulla and DeFalco 2015, p. 10); they concluded that 
Eureka Valley evening-primrose likely uses soil moisture within the top 
11.8 in (30 cm) of soil because soil moisture at greater depths varied 
little over the spring and early summer, when primrose individuals were 
actively growing.
    The growing phenologies (timing) of Eureka Valley evening-primrose 
and Russian thistle are likely sufficiently different that competition 
for water resources is minimal. The Park Service (Park Service 2014) 
observed the ``phenological asynchrony'' between these two species and 
noted that, although they share habitat in semi-stabilized sand, they 
do not appear to be stimulated by the same precipitation events and so 
do not reproduce at the same time or compete for the same resources. 
Overall at the present time, the best available information presented 
by Chow and Klinger (2013b) and Chow (2016) suggest that Russian 
thistle does not outcompete the Eureka Valley evening-primrose. 
Additionally, recent reports from the Park Service (2013, 2014) 
indicate that Eureka Valley evening-primrose continues to occupy areas 
where it was known to occur around the time of listing. Therefore, we 
do not consider impacts from Russian thistle to be a threat to the 
continued existence of the Eureka Valley evening-primrose both now and 
in the future.
Climate Change
    For a detailed discussion regarding the potential effects of 
climate change on Eureka Valley evening-primrose, both at the time of 
listing and since then, see the proposed delisting rule (79 FR 11053, 
February 27, 2014) and the Background Information document (Service 
2014), which are available under Docket No. FWS-R8-ES-2013-0131 at 
http://www.regulations.gov.
    Potential effects of climate change may include a variety of 
potential changes, such as the following:
    (1) A decrease in the level of soil moisture that could increase 
evaporation and transpiration rates and thus impact the growth or 
performance of individual plants (Weltzin et al. 2003, p. 943).
    (2) Altered timing and amount of rainfall could influence 
germination and possibly establishment of Eureka dune grass (Pavlik and 
Barbour 1986, p. 47).
    (3) The timing of phenological phases, such as flowering, leafing 
out, and seed release in both Eureka Valley evening-primrose and Eureka 
dune grass, could change, which has been noted in many other plant 
species (Bertin 2008, pp. 130-131). Additionally, pollinator 
availability could become limited (Hegland et al. 2009) during the time 
Eureka Valley evening-primrose is flowering, which in turn could affect 
pollination effectiveness, and consequently the amount of seed it 
produces.
    (4) Lower rainfall could affect survival of individual plants 
(e.g., reproductive adults, seedlings) and result in less frequent 
germination events, both of which could affect recruitment. 
Alternatively, increased rainfall could increase germination and 
survival, but could also increase competition with invasive, nonnative 
plants or increase the population size of herbivores. With respect to 
herbivores, a subsequent decrease in rainfall could result in increased 
herbivory of certain plants due to a decreased availability in the 
variety of vegetation.
    New information comprises the following: The most recent global 
climate models from the Intergovernmental Panel on Climate Change 
(IPCC) fifth assessment (IPCC 2013) do not resolve how two important 
weather patterns (i.e., the El Ni[ntilde]o Southern Oscilliation (ENSO) 
phenomenon and North American monsoon) will change over the next 
century (Cook and Seager 2013). These two weather patterns may be 
important drivers of the Eureka Valley evening-primrose population 
dynamics (Evans in litt. 2014); climate envelope forecasts indicate 
that suitable climate for Eureka Valley evening-primrose will shift to 
the northwest of Eureka Valley dunes by 2050 (Evans in litt. 2014).
    In 2016, USGS completed 3 years of field study at all three dune 
systems to evaluate the influence of rainfall and temperature patterns 
on germination and growth of Eureka Valley evening-primrose and Eureka 
dune grass (Scoles-Sciulla and DeFalco 2017); final analysis will not 
be complete until 2018. Preliminary results indicate that: (1) 
Temperature regime, wind speeds, and precipitation patterns at the 
three dunes show some differences that likely are due to their relative 
position within Eureka Valley (for instance, the Main Dunes has lower 
daily temperatures than the other two dunes, while other patterns, such 
as rainfall, vary among the three dunes on both a temporal and spatial 
scale); (2) soil moisture probes installed near Eureka Valley evening-
primrose individuals suggest that moisture at depths greater than 11.8 
in (30 cm) varied little over the spring and early summer when the 
species was actively growing; and (3) rooting depth for Eureka Valley 
evening-primrose was within the top 11.8 in (30 cm) of substrate 
(Scoles-Sciulla and DeFalco 2017). Although the study is incomplete, 
this information indicates that the extent of the annual expression of 
Eureka Valley evening-primrose may vary between dunes in part due to 
the variation in precipitation between the dunes and that the species 
is accessing soil moisture at a deeper level than Russian thistle, 
which may reduce potential competition.
    In summary, effects of climate change on Eureka Valley evening-
primrose may occur in the future, although we cannot predict what the 
effects will be. Regardless, climate change will be affecting the 
climatic norms with which this species has previously persisted, and it 
is probable that this shift could cause stress to the species. We note 
that, as a short-lived perennial, the ability of this species to shift 
geographically over time in accordance with shifting climatic norms is 
greater than would be for a long-lived perennial plant species. 
However, because of the uncertainty regarding the magnitude and the 
imminence of such a shift, we are unable to determine the extent that 
this may become a stressor in the future. Additionally, while 
uncertainty exists, we expect the Park Service will continue to manage 
and monitor the species so that corrective actions may occur in the 
future.

[[Page 8587]]

Stochastic Events
    For a detailed discussion regarding the potential effects of 
stochastic events on Eureka Valley evening-primrose, both at the time 
of listing and since then, see the proposed delisting rule (79 FR 
11053, February 27, 2014) and the Background Information document 
(Service 2014), which are available under Docket No. FWS-R8-ES-2013-
0131 at http://www.regulations.gov. In those documents, we discussed 
that environmental stochasticity (variation in recruitment and 
mortality rates in response to weather, disease, competition, 
predation, or other factors external to the population) could result 
from such events as drought, windstorms, and timing and amount of 
rainfall. There is no new information regarding the potential effects 
of stochastic events on Eureka Valley evening-primrose.
    Overall, it is possible that environmental stochasticity (in the 
form of extreme weather events) could cause stress to Eureka Valley 
evening-primrose. However, the best available information at this time 
does not indicate the impacts associated with the observed and 
predicted range of stochastic events would affect the long-term 
persistence of Eureka Valley evening-primrose.
    In our proposed rule and supporting documents, we also discussed 
that low genetic diversity theoretically could affect the ability of 
plant species to adjust to novel or fluctuating environments, survive 
stochastic events, or maintain high levels of reproductive performance 
(Huenneke 1991, p. 40). The species-rich genus Oenothera has been used 
as a model for the study of plant evolution, particularly regarding 
reproductive systems (Theiss et al. 2010). DNA analysis has been used 
to clarify phylogenetic relationships; evidence indicates that the 
genus Oenothera is polyphyletic (relating to a taxonomic group that 
does not include the common ancestor of the members of the group, and 
whose members have two or more separate origins) (Levin et al. 2003, 
2004). Despite the number of studies, however, we have no specific 
information for O. californica ssp. eurekensis indicating the level of 
genetic diversity within or among the populations. However, given the 
resiliency exhibited by the species, at this time, the best available 
information does not indicate the species is experiencing any potential 
negative effects of low genetic diversity within and among the Eureka 
Valley evening-primrose populations.
Combination of Factors
    For a detailed discussion regarding the potential effects of a 
combination of factors on Eureka Valley evening-primrose, both at the 
time of listing and since then, see the proposed delisting rule (79 FR 
11053, February 27, 2014) and the Background Information document 
(Service 2014), which are available under Docket No. FWS-R8-ES-2013-
0131 at http://www.regulations.gov. In those documents, we discussed 
that a combination of favorable climatic conditions could lead to an 
increase in food sources for small mammal populations, which could then 
cause additional stress on Eureka Valley evening-primrose through seed 
predation and herbivory. During the comment period, one peer reviewer 
commented that, although boom and bust population cycles of small 
mammals and their impacts on native vegetation are well known, in the 
case of Eureka Valley, there may be another confounding factor: Prior 
to the introduction of Russian thistle to the Valley in the last 
century, lagomorph populations were likely smaller. The spread of 
Russian thistle around the dunes may have increased the size of 
lagomorph populations above historical levels, and thus could 
potentially result in increased herbivory on Eureka Valley evening-
primrose (Thomas in litt. 2014).
    During field studies since the proposed delisting rule was 
published, researchers (Chow and Klinger 2014, pp. 19-20, 46) observed 
evidence of small mammal predation and lagomorph predation on Eureka 
Valley evening-primrose during their field studies. However, no 
quantitative data are available regarding the extent of herbivory on 
Eureka Valley evening-primrose throughout its range, the size of the 
lagomorph population (or other small mammal populations), nor how their 
numbers fluctuate with the presence of Russian thistle. In addition, 
the ``superbloom'' year of 2014 provided a qualitative confirmation 
that, despite the large expression of Russian thistle that occurred in 
2010 and the observations of small mammal herbivory in the intervening 
years, Eureka Valley evening-primrose was sufficiently resilient to 
have an aboveground expression of more than 1 million individuals.
    While the combination of factors could potentially affect Eureka 
Valley evening-primrose, the best available information does not 
indicate that cumulative or synergistic effects are of sufficient 
magnitude or extent that they are affecting the viability of the 
species at this time or into the future.

Summary of Factors Affecting the Species--Eureka Dune Grass

A. The Present or Threatened Destruction, Modification, or Curtailment 
of Its Habitat or Range
OHV Activity
    OHV activity may impact Eureka dune grass and its habitat in the 
same fashion and magnitude as that described above for Eureka Valley 
evening-primrose (see the OHV Activity section under Factor A for 
Eureka Valley evening-primrose, above). This includes 4-wheel drive 
vehicular use of roads and trails, predominantly on public lands, for 
the purpose of touring, hunting, fishing, or other public land use. 
Existing regulatory mechanisms (such as through the Park Service's 
Organic Act and other laws guiding management of Park Service lands) in 
place since listing have resulted in beneficial effects to the species, 
including management measures to control OHV and recreational 
activities) (see additional discussion under Factor D, below). As a 
result, OHV-related impacts to Eureka dune grass have essentially been 
ameliorated, in large part due to the designation of Federal wilderness 
areas throughout the species' range, with the exception of some minor 
unauthorized OHV activity that the Park Service acknowledges, also 
noting that the remote location of the dunes and limited resources make 
enforcing restrictions difficult (Park Service 2011b, p. 17).
    Additional discussion regarding potential impacts and the Park 
Service's management of OHV activity, land use designations, and the 
potential for future adaptive management strategies regarding OHV 
activities that are established to benefit Eureka dune grass and other 
Eureka Dunes ecosystem species are described in detail under the OHV 
Activity section under Factor A for the Eureka Valley evening-primrose, 
above, and in the proposed delisting rule (79 FR 11053, February 27, 
2014).
    Overall, the current level of unauthorized OHV use is sporadic and 
does not occur across the range of the species, and there does not 
appear to be any correlation between OHV recreation and the status of 
the species. Given the management of OHV activity through land use 
designations has resulted in the near elimination of OHV activity on 
Eureka Dunes at the current time, and given the likelihood that these 
protections and adaptive management strategies will continue into the 
future at the remote locations where Eureka

[[Page 8588]]

dune grass occurs, we conclude that OHV activity no longer impacts the 
species or its habitat at the population or rangewide levels currently 
and into the future.
Other Recreational Activities
    In addition to unauthorized OHV activity that may occur currently 
(as described above), other recreational activities have historically 
and currently occur (occasionally) within the Eureka Dunes, including 
horseback riding, sandboarding, camping outside of designated areas, 
and creation of access routes. Potential impacts from these 
recreational activities are described in detail either above in the 
Other Recreational Activities section under Factor A for Eureka Valley 
evening-primrose, or in the associated Other Recreational Activities 
section of the proposed delisting rule. Existing regulatory mechanisms 
(such as through the Park Service's Organic Act and other laws guiding 
management of Park Service lands) in place since listing have resulted 
in beneficial effects to the species (including management measures to 
control recreational activities) (see additional discussion above for 
Eureka Valley evening-primrose, as well as under Factor D, below).
    New information is the same as that presented above for Eureka 
Valley evening-primrose: In response to publication of the proposed 
delisting rule, the Park Service referred back to a study conducted by 
Pavlik (1979a), which found that seedlings of Eureka dune grass are 
extremely fragile and cannot tolerate even the lightest disturbance by 
foot traffic. Although the Park Service has not been able to measure 
the amount of foot traffic, the potential impacts from such traffic can 
be qualitatively observed on stabilized sand following rain events 
(Park Service 2014, p. 5). In addition, one peer reviewer observed 
evidence (i.e., tracks) of unauthorized OHV activity at the base of the 
Main Dunes, as well as increased visitor use, specifically camping, at 
the dunes since the 1980s (McLaughlin in litt. 2014).
    Our current assessment is that, while the Park Service has 
documented some unauthorized activity (e.g., sandboarding, OHV activity 
in closed areas) that may result in minor or occasional impact to 
individual plants, these are infrequent occurrences and affect very 
small areas and are not spread throughout the range of the species. The 
Park Service is aware of the potential for impacts to Eureka dune grass 
from hikers accessing the north end of the Main Dunes and considers 
this a priority area for rangers to patrol and to have visitor contact.
    Given the existing conservation measures in place across the Eureka 
Dunes (i.e., reduction or elimination of impacts associated with 
horseback riding, sandboarding, camping, and establishment of access 
points via implementation of patrols, illegal road closures, 
interpretative signs, barriers, etc.), the best available information 
at this time indicates that unauthorized OHV and other recreational 
activities, if they occur, are not causing population-level effects (as 
compared to pre-listing levels) for Eureka dune grass habitat 
currently, nor are they expected to do so in the future.
B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes
    Given the same scenario and discussion applies, please see the 
Factor B section for Eureka Valley evening-primrose, above, regarding 
collection of seeds or leaves for laboratory experiments or collection 
of voucher specimens for herbaria as a potential stressor to Eureka 
dune grass. Of the three section 10(a)(1)(A) permits issued for studies 
involving the removal of plants, seeds, or plant parts, only two of 
these were for Eureka dune grass. We do not consider this level of 
research and collection to pose any potential threat of overutilization 
for the species. We also do not have any new information regarding this 
factor, and we conclude that collection of seeds or leaves is not a 
short-term or long-term threat to the continued existence of Eureka 
dune grass.
C. Disease or Predation
    At the time of listing, disease and predation were not identified 
as potential threats to Eureka dune grass. Since then, studies imply 
that herbivory and seed predation are a potential stressor to the 
species. For a detailed discussion regarding disease and predation, 
both at the time of listing and since then, see the proposed delisting 
rule (79 FR 11053, February 27, 2014) and the Background Information 
document (Service 2014), which are available under Docket No. FWS-R8-
ES-2013-0131 at http://www.regulations.gov.
    New information comprises the following: Updated results from one 
study on plant growth and reproduction (Scoles-Sciulla and DeFalco 
2015) that was ongoing at the time of the proposed delisting rule. 
Results indicate that in 2014, out of 90 Eureka dune grass individuals 
tagged in 2013, 16 did not grow due to severe herbivore damage in 2013; 
and an additional 4 plants grew but did not reproduce (Scoles-Sciulla 
and DeFalco 2015, p. 8). In 2015, the same 16 individuals still did not 
grow, and 3 of the additional 4 plants grew but did not reproduce 
(Scoles-Sciulla and DeFalco 2016, p. 8). No herbivory effects were 
discussed with the findings for the year 2016 (Scoles-Sciulla and 
DeFalco 2017).
    In their 2015 monitoring report, the Park Service made note of 
rodent herbivory on leaves and stems of Eureka dune grass, most likely 
from kangaroo rats (Dipodomys sp.) that underwent a population surge in 
the previous year (Park Service 2015, pp. 18-19). Additionally, 
abundant rodent tracks were found in the central and southern portions 
of the Main Dunes (Park Service 2015, pp. 18-19). No studies have been 
done to quantify the extent of herbivore damage to the species. 
However, because Eureka dune grass produces seed in low abundance, the 
loss of any of this seed to herbivores could affect the ability of the 
species to bank seed and germinate in abundance when suitable 
conditions arise in the future.
    New information is also noted with regards to potential herbivory 
from lagomorphs. Thomas (in litt. 2014) cited two references that were 
inadvertently excluded in the proposed rule or Background Information 
document (Service 2014, entire). This information indicates that 
Russian thistle is consumed by black-tailed jackrabbits and cottontail 
rabbits (Daniel et al. 1993, p. 5; Fagerstone et al. 1980, pp. 230-231) 
and may be a preferred food source (Fagerstone et al. 1980, p. 230). 
Thomas (in litt. 2014) suggests that it is possible that Russian 
thistle may have increased lagomorph populations above historical 
levels, and thus, increased herbivory on Eureka dune grass. Although 
anecdotal in nature, we also note that the Park Service staff has made 
observations of herbivory by small mammals on Eureka dune grass (Park 
Service 2015, pp. 18-20).
    Seed predation and herbivory are naturally occurring processes. We 
expect that Eureka dune grass can adapt to withstand some level of 
herbivory and seed predation. Given that the species continues to 
occupy the same range as identified at the time of listing, it does not 
appear that herbivory and seed predation by themselves are occurring at 
such a level to cause population-level declines or other adverse 
effects to the species as a whole. Based on the best available 
information at this time (i.e., observations by USGS and the Park 
Service between 2013 and 2015, the expectation that this species

[[Page 8589]]

has evolved with some level of herbivory/seed predation, that 
herbivory/seed predation is naturally occurring, and some level of 
herbivory/seed predation is expected for the species), we conclude that 
the observed impacts in and of themselves are not likely causing 
population-level effects for Eureka dune grass currently. However, 
given that Eureka dune grass is already experiencing low to no 
reproduction, any additional loss of biomass due to herbivory will 
likely place additional stress on individual plants and limit their 
ability to expend resources on reproduction. Therefore, we acknowledge 
that herbivory or seed predation could be a concern for this species 
into the future, and recommend that observations of this stressor 
should continue.
D. The Inadequacy of Existing Regulatory Mechanisms
    Under this factor, we evaluate whether the stressors identified 
within the other factors may be ameliorated or exacerbated by any 
existing regulatory mechanisms or conservation efforts. Section 
4(b)(1)(A) of the Act requires that the Service take into account 
``those efforts, if any, being made by any State or foreign nation, or 
any political subdivision of a State or foreign nation, to protect such 
species. . . .'' In relation to Factor D under the Act, we interpret 
this language to require the Service to consider relevant Federal, 
State, and Tribal laws, regulations, and other such binding legal 
mechanisms that may ameliorate or exacerbate any of the threats we 
describe in threat analyses under the other four factors or otherwise 
enhance the species' conservation. Our consideration of these 
mechanisms is described in detail within each of the threats or 
stressors to the species (see discussion under each of the other 
factors).
    As similarly described above under the Factor D section for Eureka 
Valley evening-primrose, the following existing regulatory mechanisms 
and conservation actions were specifically considered and discussed as 
they relate to the stressors, under the applicable factors, affecting 
Eureka dune grass: The Wilderness Act, the Park Service Organic Act, 
and the other laws guiding management of Park Service lands. We 
concluded they are adequate to minimize and control threats to 
populations of Eureka dune grass from OHV activity, sandboarding, and 
horseback riding. Eureka dune grass and its habitat benefit from 
existing regulatory mechanisms and conservation actions, including: (1) 
Management measures to control illegal OHV activity (see Factor A 
discussion, above), including the Park Service's management policies 
(Park Service 2006); (2) the Organic Act; (3) the legal and stewardship 
mandates outlined in the Park Service's General Management Plan (Park 
Service 2002, entire); and (4) the Wilderness and Backcountry 
Stewardship Plan (Park Service 2013b, pp. 4, 5, 10, 16), given all 
areas containing populations of the species are within congressionally 
designated wilderness. The best available information indicates that 
these existing regulatory mechanisms have reduced the previously 
identified significant adverse effects to individual plants and 
populations, especially impacts associated with OHV activity (Factors A 
and E) and other recreational activities (i.e., sandboarding, camping, 
and associated access routes) (Factors A and E). We also expect the 
Park Service to continue using these mechanisms to assist in reducing 
impacts into the future. At this time, there are no existing regulatory 
mechanisms to address herbivory, seed predation, effects of climate 
change, and stochastic events under Factor E (see below).
    Downlisting Eureka dune grass from an endangered species to a 
threatened species on the Federal List of Endangered or Threatened 
Plants would not significantly change the protections afforded this 
species under the Act. Additionally, while most of the other laws, 
regulations, and policies considered are not specifically directed 
toward protection of Eureka dune grass, they mandate consideration, 
management, and protection of resources that benefit the species. We 
expect these laws, regulatory mechanisms, and management plans to 
remain in place into the future.
    For a more detailed discussion of the various existing regulatory 
mechanisms, both at the time of listing and since then, see the 
proposed delisting rule (79 FR 11053, February 27, 2014) and the 
Background Information document (Service 2014), which are available 
under Docket No. FWS-R8-ES-2013-0131 at http://www.regulations.gov. 
There is no new information concerning these regulatory mechanisms.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
OHV Activity and Other Recreational Activities
    See the OHV Activity and Other Recreational Activities sections, 
above, under Factor A for Eureka dune grass and Eureka Valley evening-
primrose for a complete discussion of realized and potential impacts 
since the time of listing. As stated there, we conclude, based on the 
best available information, that the Wilderness Area designation, 
coupled with Park Service management of OHV activity and other 
recreational activity, has significantly reduced potential impacts to 
Eureka dune grass individuals currently and into the future. Even so, 
there is one portion of the range of this species (and not affecting 
Eureka Valley evening-primrose)--the Main Dunes adjacent to the 
campground area--that is subject to the most impact from recreational 
hiking. The National Park Service has anecdotally documented foot 
traffic in this area when it is most observable, i.e., after a rain 
event (Park Service 2014, p. 5). If the area being trampled overlaps 
with an area where there has been a localized germination event of 
Eureka dune grass, it could result in the loss of those individuals as 
well as potentially prevent the species from recovering (e.g., limiting 
the species' ability to expend resources on growth and establishment 
that would increase abundance of individuals) in the area. We expect 
the Park Service to continue to manage OHV and other recreational 
activities to assist in reducing impacts to Eureka dune grass into the 
future.
Competition With Russian Thistle
    Invasive, nonnative plants can potentially impact the long-term 
persistence of endemic species. Russian thistle is the only invasive, 
nonnative species that has spread onto the dunes in the Eureka Valley. 
Potential impacts associated with Russian thistle are described under 
the Competition with Russian Thistle section under Factor E for Eureka 
Valley evening-primrose, above, and in the associated section of the 
proposed delisting rule (79 FR 11053, February 27, 2014) and the 
Background Information document (Service 2014), which are available 
under Docket No. FWS-R8-ES-2013-0131 at http://www.regulations.gov.
    The potential for Russian thistle to impact Eureka dune grass is 
unlikely because: (1) Eureka dune grass typically occurs on the 
steeper, unstable slopes of the dunes, which appears to limit the 
establishment of Russian thistle; and (2) Russian thistle roots are 
shallower than those of Eureka dune grass, which reduces the likelihood 
of potential competition between the two species.
    New information comprises the following: The Park Service continued 
to note the presence/absence of Russian thistle during the hectare grid 
monitoring in 2014 and 2015; at the Main Dunes, the number of hectares 
in the monitoring grid where Russian thistle and Eureka dune grass both 
occur

[[Page 8590]]

was 19 percent in 2013 (Park Service 2014, pp. 4, 12, 15; 2015, p. 3), 
and 4 percent in 2015 (Hoines in litt. 2017). Due to the steeper 
terrain occupied by Eureka dune grass on the Main Dunes, the percentage 
of hectares of Russian thistle that overlap with dune grass is less 
than that for overlap between Russian thistle and Eureka Valley 
evening-primrose. At the two smaller dunes, there is a greater 
percentage of hectares of Russian thistle that overlap with Eureka dune 
grass than at the Main Dunes (in 2013, 91 percent at Saline Spur Dunes, 
and 76 percent at Marble Canyon Dunes). However, on a finer spatial 
scale, the cover of each of these species (Eureka dune grass and 
Russian thistle) is so low that the opportunity for competition is 
limited. In addition, in their ecological study of Eureka dune grass, 
USGS measured the rooting depth, and found it to be approximately 35 in 
(90 cm) (Scoles-Sciulla and DeFalco 2016, p. 9). The rooting depth for 
annual species of Russian thistle is shallower (in one study, the 
average was 24 in (60 cm) (Padilla and Pugnare 2007)). There are also 
phenological differences in the growing season between Eureka dune 
grass and Russian thistle: During the growing season for Russian 
thistle (summer), adult dune grass individuals are extracting water 
from lower depths (Scoles-Sciulla and DeFalco 2016). Therefore, based 
on the best available information, although competition between 
individuals of Russian thistle and individuals of Eureka dune grass may 
occasionally occur, because of their separation in space and time, we 
conclude that competition with Russian thistle does not pose a 
population-level impact to Eureka dune grass at this time.
Climate Change
    For a detailed discussion of climate change in the Eureka Valley 
and its potential effects to Eureka dune grass and its habitat, please 
see the proposed delisting rule (79 FR 11053, February 27, 2014) and 
the Background Information document (Service 2014), which are available 
under Docket No. FWS-R8-ES-2013-0131 at http://www.regulations.gov. At 
the time we published the proposed rule, we concluded that there is 
considerable uncertainty in local climate projections, and we expected 
Eureka dune grass is adapted to withstand drier climate conditions. We 
also stated that impacts from climate change on Eureka dune grass may 
occur in the future, although we cannot predict what the effects will 
be.
    New information comprises the following: In 2016, USGS completed a 
field study at all three dune systems to evaluate the influence of 
rainfall and temperature patterns on germination and growth of Eureka 
dune grass and Eureka Valley evening-primrose; the results of this 
study are not yet available (Scoles-Sciulla and DeFalco 2017, p. 9). To 
date, they note the following:
    (1) Temperature regime, wind speeds, and precipitation patterns at 
the three dunes show some differences that likely are due to their 
relative position with Eureka Valley. For instance, the Main Dunes has 
lower daily temperatures than the other two sites, while other 
patterns, such as rainfall, vary among the three dunes on both a 
temporal and spatial scale.
    (2) Soil moisture probes installed near dune grass individuals 
suggest that moisture from a summer storm event (11 in (29 cm)) may 
infiltrate the soil near plants more deeply than away from plants. 
Also, soil moisture down to 35 in (90 cm) declined more rapidly near 
the dune grass than in the interspaces during this time when Eureka 
dune grass is actively growing.
    (3) Rooting depth for Eureka dune grass was 35 in (90 cm) during 
the 2014 and 2015 growth seasons, as compared to a ``within top [11 in] 
30 cm'' rooting depth for Eureka Valley evening-primrose (Scoles-
Sciulla and DeFalco 2017, pp. 5-8).
    There are two primary ways in which a shift in local climatic 
conditions could affect the long-term persistence of Eureka dune grass. 
First, because the species taps into water at deeper soil levels in the 
dune sands, a reduction in the availability of this water could affect 
the persistence of mature, established individuals; a loss of these 
mature individuals from the population is significant, because most of 
the seed production for the future of the population is contributed by 
these older individuals. Second, a shift in precipitation patterns 
during the summer and fall season could affect the ability of Eureka 
dune grass to have successful germination events. Water year 
precipitation (i.e., the total annual rainfall between October 1 of one 
year until September 30 of the following year) has been on a declining 
trend between 1896 and 2013 (Willoughby in litt. 2014); summer 
precipitation (April through September) has also been on a declining 
trend between 1896 and 2013 (Willoughby in litt. 2014). It is 
reasonable to assume the lack of summer precipitation is one of the 
parameters affecting the ability of Eureka dune grass to experience 
germination events. Park Service staff had documented a germination 
event in 2014, but none had been observed prior to that since 1984 
(Park Service 2014; Pavlik and Barbour 1986, p. 50). At this time, we 
have no further information regarding the extent to which the 2014 
germinants may have survived or become established within the 
population.
    In summary, impacts from climate change on Eureka dune grass may 
occur in the future. Although we cannot predict what the effects will 
be, they could impact various aspects of the life history of the 
species, including altering germination and establishment success, as 
well as growth, reproduction, and longevity. Regardless, climate change 
will be affecting the climatic norms with which this species has 
previously persisted, and it is probable that this shift could cause 
stress to the species. We note that, as a long-lived perennial, the 
ability of this species to shift geographically over time in accordance 
with shifting climatic norms is less than would be for a short-lived 
perennial (for example, Eureka Valley evening-primrose) or annual plant 
species. The conditions for germination (specifically, late summer/
early fall precipitation) occur less frequently than the typical winter 
precipitation to which most annual and perennial Mojave desert species 
respond. Although several patches of germination were observed by the 
Park Service in 2014, that was the only year since rangewide monitoring 
began in 2008 that they observed such germination. Because of the 
uncertainty regarding the magnitude and the imminence of such a shift 
in climatic norms, we are unable to determine the extent to which this 
will become a stressor in the foreseeable future, and particularly how 
it will affect the interval between successful germination and 
establishment events that the species needs to replace the loss of 
senescent individuals.
Stochastic Events
    For a detailed discussion of the potential impacts of stochastic 
events on Eureka dune grass and its habitat, see the ``Stochastic 
Events'' section of the proposed delisting rule (79 FR 11053, February 
27, 2014) and the Background Information document (Service 2014, pp. 
62-64). At the time we published the proposed rule, we concluded that 
neither windstorms nor a variation in rainfall represent a substantial 
threat to Eureka dune grass. We have no new information regarding the 
potential threat posed by stochastic events.
    With regard to genetic stochasticity, we stated in the proposed 
delisting rule that low genetic diversity may affect the ability of 
plant species to adjust to novel or fluctuating environments, survive

[[Page 8591]]

stochastic events, or maintain high levels of reproductive performance 
(Huenneke 1991, p. 40). Although Bell (2003, p. 6) concluded that there 
was low genetic diversity within and among the three populations of 
Eureka dune grass, there is no past information available regarding the 
level of genetic diversity within and among the three populations of 
Eureka dune grass that would allow us to determine if genetic diversity 
has changed over time or the extent to which low genetic diversity may 
affect the species' fitness or its ability to adapt to changing 
conditions over time. Overall, we concluded in the proposed delisting 
rule that genetic stochasticity does not pose a threat to Eureka dune 
grass currently or in the future.
    Currently, we have no additional information on whether genetic 
diversity has changed over time, or whether genetic stochasticity poses 
a threat to Eureka dune grass in the future.
Combination of Factors
    For a detailed discussion of the combination of various factors and 
potential impacts on Eureka dune grass and its habitat, see the 
``Combination of Factors'' section of the proposed delisting rule (79 
FR 11053, February 27, 2014), and the Background Information document 
(Service 2014), which are available under Docket No. FWS-R8-ES-2013-
0131 at http://www.regulations.gov. We concluded that while the 
combination of factors could potentially impact Eureka dune grass, the 
best available information did not indicate that the magnitude or 
extent of cumulative or synergistic effects was impacting the species 
to the point that they are affecting the viability of the species at 
this time or into the future (although the available information 
indicates some uncertainty about how synergistic effects could impact 
the species in the future).
    The best available information for Eureka dune grass indicates that 
the rangewide distribution (as represented by presence in the grid 
monitoring), as well as the number of large individuals of the dune 
grass, is in decline at two (the Main Dunes and Marble Canyon Dunes) 
out of three of the dune systems. In addition, since most of Eureka 
dune grass occurs at the Main Dunes, the decline in abundance and 
distribution at the Main Dunes represents a larger proportion of the 
decline rangewide for the species. Although we do not know specifically 
what the combination of factors may be contributing to the decline of 
Eureka dune grass, the combination of rangewide distribution 
monitoring, 30 years of photopoints, and trends analysis by three 
different parties (Kendall in litt. 2014; Park Service 2014; and 
Willoughby in litt. 2014) indicate that the status of this species is 
not yet stable or improving. This species exhibits life-history 
characteristics (intrinsic factors) that include low seed production, 
low frequency of germination, and low frequency of establishment of new 
individuals that reach reproductive age. These characteristics 
contribute to the difficultly of maintaining robust populations of 
individuals over time. Any additional external (extrinsic) factors, 
such as trampling, herbivory, or drought, that impact these critical 
life-history stages in Eureka dune grass will reduce its reproductive 
potential, and its ability to persist, in the future.
    Please see the Climate Change section under Factor E, above, for a 
discussion of its potential effect as a stressor to Eureka dune grass. 
At this time, our evaluation of the best available information 
indicates that the combination of stress caused by changing climatic 
norms with other stressors, such as herbivory, are likely exacerbating 
the species' ability to exhibit a stable or increasing population size 
across its range into the future. We also note that the best available 
information suggests this species is physiologically adapted to the 
specific hydrologic and soil conditions on the dunes. However, both 
water year precipitation and summer precipitation have declined in the 
region between 1896 and 2013; these declines could affect the species 
by reducing successful germination events and recruitment in the 
summer-fall months and also by reducing the health and longevity of 
established adults due to lower annual rainfall.
    With respect to herbivory (please see the Factor C section above), 
it is possible that the abundance of lagomorphs (due to presence of 
Russian thistle that it feeds on) has increased greater than historical 
levels, and thus may contribute to elevated levels of herbivory on 
Eureka dune grass (Thomas in litt. 2014). Although anecdotal in nature, 
we also note that the Park Service staff has made observations of 
herbivory by small mammals on Eureka dune grass (Park Service 2015, pp. 
18-20).

Determinations

Introduction

    Under section 4(a)(1) of the Act, we determine whether a species is 
an endangered species or threatened species because of any of the 
following: (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.
    The fundamental question before the Service is whether the species 
meets the definition of ``endangered species'' or ``threatened 
species'' under the Act. To make this determination, we evaluated the 
projections of extinction risk, described in terms of the condition of 
current and future populations and their distribution (taking into 
account the risk factors and their effects on those populations). For 
any species, as population condition declines and distribution shrinks, 
the species' extinction risk increases and overall viability declines.
    The Act defines an endangered species as any species that is ``in 
danger of extinction throughout all or a significant portion of its 
range'' and a threatened species as any species ``which is likely to 
become an endangered species within the foreseeable future throughout 
all or a significant portion of its range.'' On July 1, 2014, we 
published a final policy interpreting the phrase ``significant portion 
of its range'' (SPR) (79 FR 37578). In our policy, we interpret the 
phrase ``significant portion of its range'' in the Act's definitions of 
``endangered species'' and ``threatened species'' to provide an 
independent basis for listing a species in its entirety; thus there are 
two situations (or factual bases) under which a species would qualify 
for listing: A species may be in danger of extinction or likely to 
become so in the foreseeable future throughout all of its range; or a 
species may be in danger of extinction or likely to become so 
throughout a significant portion of its range. If a species is in 
danger of extinction throughout an SPR, it, the species, is an 
``endangered species.'' The same analysis applies to ``threatened 
species.''
    Our final policy addresses the consequences of finding a species is 
in danger of extinction in an SPR, and what would constitute an SPR. 
The final policy states that (1) if a species is found to be endangered 
or threatened throughout a significant portion of its range, the entire 
species is listed as an endangered species or a threatened species, 
respectively, and the Act's protections apply to all individuals of the 
species wherever found; (2) a portion of the range of a species is

[[Page 8592]]

``significant'' if the species is not currently endangered or 
threatened throughout all of its range, but the portion's contribution 
to the viability of the species is so important that, without the 
members in that portion, the species would be in danger of extinction, 
or likely to become so in the foreseeable future, throughout all of its 
range; (3) the range of a species is considered to be the general 
geographical area within which that species can be found at the time 
the Service or the National Marine Fisheries Service makes any 
particular status determination; and (4) if a vertebrate species is 
endangered or threatened throughout an SPR, and the population in that 
significant portion is a valid DPS, we will list the DPS rather than 
the entire taxonomic species or subspecies.
    The SPR policy is applied to all status determinations, including 
analyses for the purposes of making listing, delisting, and 
reclassification determinations. The procedure for analyzing whether 
any portion is an SPR is similar, regardless of the type of status 
determination we are making. The first step in our assessment of the 
status of a species is to determine its status throughout all of its 
range. Depending on the status throughout all of its range, we will 
subsequently examine whether it is necessary to determine its status 
throughout a significant portion of its range. If we determine that the 
species is in danger of extinction, or likely to become so in the 
foreseeable future, throughout all of its range, we list the species as 
an endangered (or threatened) species and no SPR analysis will be 
required. The same factors apply whether we are analyzing the species' 
status throughout all of its range or throughout a significant portion 
of its range.
    As described in our policy, once the Service determines that a 
``species''--which can include a species, subspecies, or distinct 
population segment (DPS)--meets the definition of ``endangered 
species'' or ``threatened species,'' the species must be listed in its 
entirety and the Act's protections applied consistently to all 
individuals of the species wherever found (subject to modification of 
protections through special rules under sections 4(d) and 10(j) of the 
Act).
    For the purpose of these determinations, we note that the 
implementation timeline of Death Valley National Park's Wilderness and 
Backcountry Stewardship Plan (Park Service 2013b) is 20 years. We think 
this is an appropriate timeframe over which events or effects 
reasonably can or should be anticipated, or trends extrapolated, 
because it is the length of time that the Park has planned for managing 
the habitat of Eureka Valley evening-primrose and Eureka dune grass, 
and during which time the Park will be monitoring the status of the 
populations. Although we expect this beneficial management to occur for 
at least the length of this timeframe, we expect management of the 
Eureka Dunes to continue well into the future beyond 20 years. Based on 
the Park Service's track record for natural resource management and 
revisions to management plans, we can reasonably expect such revisions 
to incorporate protective management consistent with the needs of the 
species well into the future and beyond the existing 20-year 
stewardship plan timeframe described above. We expect future revisions 
to be consistent with laws, regulations, and policies governing Federal 
land management planning; however, we cannot predict the exact contents 
of future plans. For additional information used to determine 
foreseeable future for these species, see the discussion of the Park 
Service's responsibilities and a description of Death Valley National 
Park's Wilderness and Backcountry Stewardship Plan in the ``Recovery'' 
and ``Factor D'' sections of the Background Information document 
(Service 2014, pp. 32-38, 48-51).
    In considering what factors might constitute threats to the 
species, we must look beyond the mere exposure of the species to the 
factor to determine whether the exposure causes actual impacts to the 
species. If there is exposure to a factor, but no response, or only a 
positive response, that factor is not a threat. If there is exposure 
and the species responds negatively, the factor may be a threat and we 
then attempt to determine how significant the threat is. If the threat 
is significant, it may drive, or contribute to, the risk of extinction 
of the species such that the species warrants listing as an endangered 
species or a threatened species as those terms are defined by the Act. 
This does not necessarily require empirical proof of a threat. The 
combination of exposure and some corroborating evidence of how the 
species is likely impacted could suffice. The mere identification of 
factors that could impact a species negatively is not sufficient to 
compel a finding that listing is appropriate; we require evidence that 
these factors individually or cumulatively are operative threats that 
act on the species to the point that the species meets the definition 
of an endangered species or threatened species under the Act.

Eureka Valley Evening-Primrose--Determination of Status Throughout All 
of Its Range

    As required by section 4(a)(1) of the Act, we conducted a review of 
the status of this plant and assessed the five factors to evaluate 
whether Eureka Valley evening-primrose is in danger of extinction 
currently or likely to become so in the foreseeable future 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 information presented in the 2010 
petition, information available in our files and gathered through the 
status review initiated with our 90-day finding in response to this 
petition, additional information that became available since the time 
our 2007 5-year status reviews were completed, and other available 
published and unpublished information, including public comments and 
information available after publication of the proposed rule. We also 
consulted with species experts and land management staff with Death 
Valley National Park who are actively managing for the conservation of 
Eureka Valley evening-primrose.
    We examined the following stressors that may be affecting Eureka 
Valley evening-primrose: Unauthorized OHV activity, and other 
unauthorized recreational activities (specifically, horseback riding, 
sandboarding, camping, and access routes) (Factor A); collection for 
scientific research (Factor B); herbivory and seed predation (Factor 
C); the inadequacy of existing regulatory mechanisms (Factor D); and 
other unauthorized recreational activities (i.e., horseback riding, 
sandboarding, camping, and access routes), competition with Russian 
thistle, effects of climate change, and stochastic events (Factor E). 
Our analysis indicates that measures have been put in place since the 
time of listing that have resulted in management and the elimination or 
reduction of the significant impacts to Eureka Valley evening-primrose 
populations identified at the time of listing (i.e., OHV activity, and 
to a lesser extent camping and unauthorized OHV activity) that could 
have resulted in the extirpation of all or parts of populations. These 
impacts have been eliminated or reduced to the extent that they are 
considered negligible currently, and are expected to continue to be 
negligible into the future.
    It is important to acknowledge the significant commitment made 
initially by BLM and subsequently by the Park Service in their efforts 
to provide

[[Page 8593]]

permanent protection to Eureka Valley evening-primrose and its habitat, 
as well as ongoing management, research, and public outreach 
opportunities. Since the publication of the proposed delisting rule in 
2014, the Park Service continued to monitor the species for presence/
absence throughout its range in 2014 and 2015 and developed a new 
subsampling method that was initiated in 2017. In addition, the Park 
Service coordinated with researchers to promote additional studies on 
monitoring methodologies (Chow and Klinger 2016), examine competition 
with Russian thistle (Chow and Klinger 2016), and investigate how 
growth and reproduction are influenced by changes in local climate 
(Scoles-Sciulla and DeFalco 2017). The Park Service worked with us to 
develop a post-delisting monitoring plan for Eureka Valley evening-
primrose, which commits the Park Service to continued monitoring of 
this species for a period of 10 years.
    The recovery criteria in the recovery plan have been achieved and 
the recovery objectives identified in the recovery plan have been met 
for Eureka Valley evening-primrose, based on the information presented 
in this final rule, the proposed rule (79 FR 11053, February 27, 2014), 
and the Background Information document (Service 2014), which are 
available under Docket No. FWS-R8-ES-2013-0131 at http://www.regulations.gov.
    In conclusion, as discussed in the Summary of Factors Affecting the 
Species--Eureka Valley Evening-primrose section above, herbivory, seed 
predation, stochastic events, climate change, and competition with 
Russian thistle during years the thistle is abundant have the potential 
to impact Eureka Valley evening-primrose currently or into the 
foreseeable future. However, the best available information at this 
time indicates a negligible impact or lack of impact to the species 
across its range, although localized impacts may be affecting 
individual Eureka Valley evening-primrose plants in portions of 
populations within the range (e.g., documented herbivory and seed 
predation at the north end of the Main Dunes).
    Therefore, after review and analysis of the information regarding 
stressors as related to the five statutory factors, we find that the 
ongoing stressors are not of sufficient imminence, scope, or magnitude, 
either individually or in combination, to indicate that Eureka Valley 
evening primrose is presently in danger of extinction throughout all of 
its range, nor are any potential stressors described herein expected to 
rise to the level that would likely cause the species to become in 
danger of extinction in the foreseeable future throughout all of its 
range. Thus, we conclude that Eureka Valley evening-primrose is not in 
danger of extinction throughout all of its range nor is it likely to 
become so in the foreseeable future.

Eureka Dune Grass--Determination of Status Throughout All of Its Range

    As required by section 4(a)(1) of the Act, we conducted a review of 
the status of Eureka dune grass and assessed the five factors to 
evaluate whether it is endangered or threatened 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 information presented in the 2010 petition, 
information available in our files and gathered through the status 
review initiated with our 90-day finding in response to this petition, 
additional information that became available since the time our 2007 5-
year status reviews were completed, and other available published and 
unpublished information, including public comments and information 
available after publication of the 2014 proposed delisting rule. We 
also consulted with species experts and land management staff with 
Death Valley National Park who are actively managing for the 
conservation of Eureka dune grass.
    We examined the following stressors that may be affecting Eureka 
dune grass: Unauthorized OHV activity, other unauthorized recreational 
activities (specifically, horseback riding, sandboarding, camping, and 
access routes)) (Factor A); collection for scientific research (Factor 
B); herbivory and seed predation (Factor C); the inadequacy of existing 
regulatory mechanisms (Factor D); and other unauthorized recreational 
activities (i.e., horseback riding, sandboarding, camping, hiking, and 
access routes), competition with Russian thistle, climate change, and 
stochastic events (Factor E). The most significant impacts to Eureka 
dune grass populations at the time of listing (i.e., OHV activity, and 
to a lesser extent camping and unauthorized OHV activity) that placed 
the species in danger of extinction at that time have been eliminated 
or reduced (as a result of the significant commitment made initially by 
BLM and subsequently by the Park Service to implement management 
measures) to the extent that they are considered negligible currently, 
and are expected to continue to be negligible into the future.
    Of the factors identified above, herbivory, seed predation, 
recreational hiking on the Main Dunes, climate change, or potentially a 
combination of these stressors may have the potential to impact Eureka 
dune grass currently or into the foreseeable future. We found that the 
best available information does not indicate that these stressors are 
affecting individual populations or the species as a whole across its 
range to the extent that they currently are of sufficient imminence, 
scope, or magnitude to rise to the level that Eureka dune grass is an 
endangered species (i.e., presently in danger of extinction throughout 
all of its range). However, our review of new information and comments 
received indicate that, while the overall range of the species is 
generally the same as it has been since the time of listing, the 
abundance and density of the species is being reduced across much of 
its range. Specifically, the best available information indicates there 
is a continued decline in abundance and density, low seed production, 
and low recruitment, despite the Park Service's management. Thus, one 
or more stressors are likely still acting on the species at the 
population level, likely contributing to the observed decline in 
abundance and density, and likely contributing to the lack of 
sufficient recruitment necessary for stable or ideally increasing 
populations.
    Although some factors may be causing stress to portions of 
populations within the range of the species (e.g., documented herbivory 
and seed predation at the north end of the Main Dunes), we do not know 
the cause of the reduction in abundance and density rangewide. The 
observed decline does not appear to be an imminent issue for the 
species. Rather, the decline appears to be occurring slowly over time. 
It is likely that, as a long-lived species in which adults have well-
established root systems and are able to persist through short periods 
of stress, it may be difficult to detect the effects of that stress 
until sometime into the future. Furthermore, the existing regulatory 
mechanisms are sufficient to manage the habitat of the species, with 
respect to potential impacts from OHV and other recreation.
    In conclusion, we have carefully assessed the best scientific and 
commercial information available regarding the past, present, and 
future threats faced by Eureka dune grass. After review and analysis of 
the best available information regarding stressors as related to the 
five statutory factors, we find that Eureka dune grass is not currently 
in danger of extinction throughout its range; however, the ongoing 
threats are of sufficient

[[Page 8594]]

imminence, scope, or magnitude to indicate that this species is likely 
to become an endangered species within the foreseeable future 
throughout all of its range.

Significant Portion of the Range

Introduction
    Consistent with our interpretation that there are two independent 
bases for listing species as described above, after examining the 
status of Eureka Valley evening-primrose and Eureka dune grass 
throughout all of their ranges, we now examine whether it is necessary 
to determine their status throughout a significant portion of their 
ranges. Per our final SPR policy, we must give operational effect to 
both the ``throughout all'' of its range language and the SPR phrase in 
the definitions of ``endangered species'' and ``threatened species.'' 
We have concluded that to give operational effect to both the 
``throughout all'' language and the SPR phrase, the Service should 
conduct an SPR analysis if (and only if) a species does not warrant 
listing according to the ``throughout all'' language.
    If the species is neither endangered nor threatened throughout all 
of its range, we determine whether the species is endangered or 
threatened throughout a significant portion of its range. To undertake 
this analysis, we first identify any portions of the species' range 
that warrant further consideration. The range of a species can 
theoretically be divided into portions in an infinite number of ways. 
However, there is no purpose in analyzing portions of the range that 
have no reasonable potential to be significant or in analyzing portions 
of the range in which there is no reasonable potential for the species 
to be endangered or threatened. To identify only those portions that 
warrant further consideration, we determine whether there is 
substantial information indicating that there are any portions of the 
species' range: (1) That may be ``significant'' and (2) where the 
species may be in danger of extinction or likely to become so within 
the foreseeable future. We emphasize that answering these questions in 
the affirmative is not a determination that the species is in danger of 
extinction or likely to become so in the foreseeable future throughout 
a significant portion of its range--rather, it is a step in determining 
whether a more-detailed analysis of the issue is required.
    In practice, one key part of identifying portions for further 
analysis may be whether the threats or effects of threats are 
geographically concentrated in some way. If a species is not in danger 
of extinction or likely to become so in the foreseeable future 
throughout all of its range and the threats to the species are 
essentially uniform throughout its range, then the species is not 
likely to be in danger of extinction or likely to become so in the 
foreseeable future in any portion of its range and 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.
    We evaluate the significance of the portion of the range based on 
its biological contribution to the conservation of the species. For 
this reason, we describe the threshold for ``significant'' in terms of 
an increase in the risk of extinction for the species. We conclude in 
our policy that such a biologically based definition of ``significant'' 
best conforms to the purposes of the Act, is consistent with judicial 
interpretations, and best ensures species' conservation. We determine 
if a portion's biological contribution is so important that the portion 
qualifies as ``significant'' by asking whether, without that portion, 
the status of the species would be so impaired that the species would 
be in danger of extinction or likely to become so in the foreseeable 
future (i.e., would be an ``endangered species'' or a ``threatened 
species''). Conversely, we would not consider the portion of the range 
at issue to be ``significant'' if there is sufficient viability 
elsewhere in the species' range that the species would not be in danger 
of extinction or likely to become so throughout its range even if the 
population in that portion of the range in question became extirpated 
(extinct locally).
    If we identify any portions (1) that may be significant and (2) 
where the species may be in danger of extinction or likely to become so 
in the foreseeable future, we engage in a more-detailed analysis to 
determine whether these standards are indeed met. The identification of 
an SPR does not create a presumption, prejudgment, or other 
determination as to whether the species is in danger of extinction or 
likely to become so in the foreseeable future in that identified SPR. 
We must go through a separate analysis to determine whether the species 
is in danger of extinction or likely to become so in the SPR. To make 
that determination, we will use the same standards and methodology that 
we use to determine if a species is in danger of extinction or likely 
to become so in the foreseeable future throughout all of its range.
    If we have identified portions of the species' range for further 
analysis, we conduct a detailed analysis of the significance of the 
portion and the status of the species in that portion. Depending on the 
biology of the species, its range, and the threats it faces, it might 
be more efficient for us to address the significance question first or 
the status question first. If we address significance first and 
determine that a portion of the range is not ``significant,'' we do not 
need to determine whether the species is in danger of extinction or 
likely to become so in the foreseeable future there; if we address the 
status of the species in portions of its range first and determine that 
the species is not in danger of extinction or likely to become so in a 
portion of its range, we do not need to determine if that portion is 
``significant.''
Eureka Valley Evening-Primrose--Significant Portion of Its Range 
Analyses
    Because we determined that Eureka Valley evening-primrose is not in 
danger of extinction or likely to become so in the foreseeable future 
throughout all of its range, we will consider whether there are any 
significant portions of its range in which Eureka Valley evening-
primrose is in danger of extinction or likely to become so in the 
foreseeable future.
    Applying the process described above to identify whether any 
portions of a species' range warrant further consideration, we 
determine whether there is substantial information indicating that: (1) 
Particular portions may be significant, and (2) the species may be in 
danger of extinction in those portions or likely to become so within 
the foreseeable future. To identify portions where a species may be in 
danger of extinction or likely to become so in the foreseeable future, 
we consider whether there is substantial information to indicate that 
any threats or effects of threats are geographically concentrated in 
any portion of the species' range.
    We consider the ``range'' of Eureka Valley evening-primrose to 
include three populations, all encompassed within the three dune 
systems (Marble Canyon Dunes, Saline Spur Dunes, and the Main Dunes 
(the latter also sometimes referred to as the Eureka Dunes)) that span 
a distance of 9 mi (14.4 km) from west to east within Eureka Valley in 
Death Valley National Park, Inyo County, California. The three 
populations have likely been present since the beginning of the 
Holocene era when pluvial lakes retreated during a warming phase, 
leaving behind the dune systems in Eureka Valley.

[[Page 8595]]

Historical distribution of Eureka Valley evening-primrose beyond the 
three currently recognized populations is unknown. In other words, the 
current distribution of the species is the only known distribution, 
which has remained generally the same since it was first recorded in 
1976.
    We considered whether the factors that could cause stress to Eureka 
Valley evening-primrose individuals or to the populations as a whole 
might be different at any one of the populations relative to each 
other. The factors we identified that could still cause stress to the 
species include: Herbivory, seed predation, stochastic events, climate 
change, and competition with Russian thistle during years the thistle 
is abundant. There are two characteristics of the habitat for the 
species that could influence the extent to which these factors cause 
stress to the species: (1) The type of dune system that supports each 
of the populations, and (2) the extent of the sandy dune habitat that 
supports each of the populations (please see the ``Environmental 
Setting'' section of the Background Information document (Service 2014, 
pp. 4-7) for more information). We compare the three dunes to each 
other as follows.

           Table 1--Comparison of Dune Habitat Characteristics at Three Dune Systems in Eureka Valley
----------------------------------------------------------------------------------------------------------------
                                                                           Extent of dune habitat (acres (ac))
               Dune system                      Type of dune system                  (hectares (ha))
----------------------------------------------------------------------------------------------------------------
1. Marble Canyon Dunes...................  Obstacle dune...............  610 ac (247 ha).
2. Saline Spur Dunes.....................  Obstacle dune...............  238 ac (96 ha).
3. Main Dunes (a.k.a. Eureka Dunes)......  Sand mountain/Transverse....  2,003 ac (811 ha).
----------------------------------------------------------------------------------------------------------------

    The type of dune system is important because of the way each of 
them intercepts, stores, and delivers moisture (from precipitation) to 
a plant at critical times in its life cycle, specifically during seed 
germination (needs moisture closer to the surface where the seeds are), 
and during growth (needs moisture deeper below the surface where the 
roots are). As Park Service monitoring over the last 9 years indicates, 
a ``good'' year for Eureka Valley evening-primrose at one dune system 
is not necessarily a ``good'' year for the species at another dune 
system. Although the mechanisms are complex and not entirely 
understood, it is likely that obstacle dunes have little capacity to 
store water, and thus intercept and deliver moisture over a shorter 
period of time. In comparison, the sand mountain type of dune system 
has a greater capacity to store water, and to deliver moisture to 
plants over a longer period of time. Therefore, if rainfall were 
abundant and equal at all three dune systems, the Main Dunes would 
provide an inherent advantage relative to Marble Canyon Dunes and 
Saline Spur Dunes, with respect to the ability of the dune system to 
provide sustained moisture for germination and growth of Eureka Valley 
evening-primrose.
    The extent of dune habitat is important because, if rainfall were 
abundant and equal at all three dune systems, the greater extent of 
dune habitat at the Main Dunes would provide more space for Eureka 
Valley evening-primrose to germinate and grow than at Marble Canyon 
Dunes and Saline Spur Dunes. While not every hectare of each dune 
provides suitable conditions for germination and growth of Eureka 
Valley evening-primrose, a comparison of the extent of dune habitat is 
still a useful relative measure of potentially suitable habitat: The 
Main Dunes is over three times as large as Marble Canyon Dunes, and 
eight times as large as Saline Spur Dunes. Thus, if rainfall were 
abundant and equal at all three dune systems, the Main Dunes provides 
an inherent advantage to Eureka Valley evening-primrose relative to 
Marble Canyon Dunes and Saline Spur Dunes, both with respect to type of 
dune system and extent of dune habitat, and would theoretically support 
the largest population of the species.
    The factors we identified that could cause stress to Eureka Valley 
evening-primrose currently or in the future are herbivory, seed 
predation, stochastic events, climate change, and competition with 
Russian thistle during years the thistle is abundant. All of these 
factors are known to cause stress in plant species; the extent to which 
they cause stress to Eureka Valley evening-primrose has not been 
studied in detail. Stress in plant populations can manifest in many 
forms, ranging from death of individuals to reduced vigor and growth of 
individuals to reduced reproductive success. In general, small plant 
populations are more vulnerable than large plant populations to factors 
that cause stress because there are fewer numbers of individuals to act 
as a ``reserve'' from which the species can recover. Moreover, once 
populations become small because of stress caused by one factor, they 
are more vulnerable to stress caused by other factors, hence the 
``Combination of Factors'' phenomenon as discussed under the Summary of 
Factors Affecting the Species section. The best available information 
indicates that the factors that cause stress could be equally present 
at all three dunes.
    Because Marble Canyon Dunes and Saline Spur Dunes are obstacle 
dunes with less water-holding capacity than the Main Dunes and comprise 
a smaller extent of dune habitat than the Main Dunes, they likely will, 
over time (under conditions of abundant and equal rainfall), support 
smaller populations of Eureka Valley evening-primrose than the Main 
Dunes. Furthermore, these smaller populations could be more vulnerable 
to factors that cause stress than the population at the Main Dunes; 
therefore, the level of stress to which populations at Marble Canyon 
Dunes and Saline Spur Dunes are subjected could be higher than the 
level of stress to which the populations at the Main Dunes are 
subjected. However, the best available data at this time do not 
indicate a higher level of stress at any of the populations/dunes as 
compared to other populations/dunes (although 2014 had the largest 
abundance for all three dunes, over the monitoring period since 2008, 
each of the dunes has shown increases and decreases over time, with no 
discernible pattern). In addition, we think that the three dune systems 
are close enough in proximity to each other that given Eureka Valley 
evening-primrose's abundant seed production in favorable years, 
migration of propagules from areas of higher concentration to areas of 
lower concentration likely mitigates for the increased vulnerability of 
the populations at Marble Canyon Dunes and Saline Spur Dunes as 
compared to the Main Dunes (Pavlik and Barbour 1985, pp. 24-53; and see 
discussion on seed dispersal and metapopulations in Cain et al. 2000, 
p. 1,220).
    Based on our evaluation of the factors that cause stress to Eureka 
Valley evening-primrose at the three

[[Page 8596]]

populations where it occurs, the factors that may cause stress are 
neither sufficiently concentrated nor of sufficient magnitude to 
indicate that the species is in danger of extinction, or likely to 
become so within the foreseeable future, at any of the areas that 
support populations of the species. Therefore, no portion of Eureka 
Valley evening-primrose's range warrants a detailed SPR analysis.
Eureka Dune Grass--Significant Portion of Its Range Analyses
    Because we found that Eureka dune grass is likely to become in 
danger of extinction in the foreseeable future throughout all of its 
range, per our Service's Significant Portion of its Range (SPR) Policy 
(79 FR 37578, July 1, 2014), no portion of its range can be significant 
for purposes of the definitions of endangered species and threatened 
species. We therefore do not need to conduct an analysis of whether 
there is any significant portion of its range where the species is in 
danger of extinction or likely to become so in the foreseeable future.
    While we conclude an SPR analysis is not necessary, we note that, 
similar to Eureka Valley evening primrose, the type of dune system and 
extent of sandy dune habitat could influence the extent to which 
factors continuing to affect the species could cause stress to Eureka 
dune grass. However, as noted above, all three populations of dune 
grass benefit from management by the National Park Service that has 
eliminated or substantially reduced the impacts associated with OHV and 
other recreational activities, removing the imminent threat of habitat 
destruction or modification. Similar to Eureka Valley evening-primrose, 
the available data do not indicate a higher level of stress at any of 
the populations/dunes as compared to the others and the remaining 
stressors are likely affecting all three populations similarly such 
that none are likely to have a different status or be at greater risk.
    Therefore, we conclude the species is a threatened species because 
of its status throughout all of its range.

Summary of the Determination for Eureka Valley Evening-Primrose

    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
faced by Eureka Valley evening-primrose. After review and analysis of 
the information regarding stressors as related to the five statutory 
factors, we find that the ongoing stressors are not of sufficient 
imminence, intensity, or magnitude to indicate that this species is 
presently in danger of extinction throughout all or a significant 
portion of its range. Additionally, no threats exist currently nor are 
any potential stressors expected to rise to the level that would likely 
cause the species to become in danger of extinction in the foreseeable 
future throughout all or a significant portion of its range. Because 
the species is neither in danger of extinction now nor likely to become 
so in the foreseeable future throughout all or any significant portion 
of its range, the species does not meet the definition of an endangered 
species or threatened species. As a consequence of this determination, 
we find that the Eureka Valley evening-primrose no longer requires the 
protection of the Act, and we are removing Eureka Valley evening-
primrose from the Federal List of Endangered and Threatened Plants.

Summary of the Determination for Eureka Dune Grass

    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
faced by Eureka dune grass. After review and analysis of the 
information regarding stressors as related to the five statutory 
factors, we find that the ongoing stressors are no longer of sufficient 
imminence, intensity, or magnitude to indicate that this species is 
presently in danger of extinction throughout all or a significant 
portion of its range. However, we find that the stressors acting upon 
Eureka dune grass are of sufficient imminence, scope, or magnitude to 
indicate that they are continuing to result in impacts at either the 
population or rangewide scales, albeit to a lesser degree than at the 
time of listing, and we find that Eureka dune grass meets the statutory 
definition of a threatened species (i.e., likely to become an 
endangered species in the foreseeable future throughout all or a 
significant portion of its range). As a consequence of this 
determination, we are reclassifying the species from an endangered 
species to a threatened species on the Federal List of Endangered and 
Threatened Plants.

Effects of the Rule

    This final rule revises 50 CFR 17.11(h) by removing Eureka Valley 
evening-primrose from the List of Endangered and Threatened Plants. The 
prohibitions and conservation measures provided by the Act, 
particularly through sections 7 and 9, no longer apply to this species. 
Federal agencies are no longer required to consult with the Service 
under section 7 of the Act to ensure that any action they authorize, 
fund, or carry out is not likely to jeopardize the continued existence 
of this species.
    This rule also revises 50 CFR 17.11(h) to reclassify Eureka dune 
grass from an endangered species to a threatened species on the Federal 
List of Endangered and Threatened Plants. However, this 
reclassification does not significantly change the protection afforded 
to this species under the Act. Anyone removing and reducing to 
possession the species from areas under Federal jurisdiction, or 
otherwise engaging in activities prohibited under 50 CFR 17.71, is 
subject to a penalty under section 11 of the Act. Pursuant to section 7 
of the Act, Federal agencies must ensure that any actions they 
authorize, fund, or carry out are not likely to jeopardize the 
continued existence of Eureka dune grass. Whenever a species is listed 
as a threatened species, the Act allows promulgation of special rules 
under section 4(d) to prohibit any act prohibited by section 9(a)(1) 
(for wildlife) or section 9(a)(2) (for plants) when it is deemed 
necessary and advisable to provide for the conservation of the species. 
The Service has promulgated a general rule providing standard 
protections for threatened species found under section 9 of the Act and 
Service regulations at 50 CFR 17.31 (for wildlife) and 17.71 (for 
plants). No species-specific special section 4(d) rule is proposed, or 
anticipated to be proposed, for Eureka dune grass, and the general 
prohibitions provided under 50 CFR 17.71 will apply. Recovery actions 
directed toward Eureka dune grass will continue to be implemented, as 
funding allows, and in coordination with the Park Service.

Future Conservation Measures

    Section 4(g)(1) of the Act requires us, in cooperation with the 
States, to implement a system to monitor effectively for not less than 
5 years the status of all species that have been recovered and 
delisted. The purpose of this requirement is to develop a program that 
detects the failure of any delisted species to sustain itself without 
the protective measures provided by the Act. If at any time during the 
monitoring period, data indicate that protective status under the Act 
should be reinstated, we can initiate listing procedures, including, if 
appropriate, emergency listing under section 4(b)(7) of the Act. The 
management practices of, and commitments by, the Park Service under 
existing laws, regulations, and policies should afford adequate 
protection to Eureka Valley evening-primrose into the foreseeable 
future upon delisting, as the entire known

[[Page 8597]]

range of this species occurs within Death Valley National Park.

Post-Delisting Monitoring Plan--Eureka Valley Evening-Primrose

    We have worked cooperatively with the National Park Service, 
California Department of Fish and Wildlife, and other interested 
parties to develop a strategy to implement appropriate monitoring 
activities for Eureka Valley evening-primrose for a term of 10 years. 
The results of such monitoring, if not consistent with a recovered 
status for the species, could trigger additional management actions, 
trigger additional or extended monitoring, or trigger status reviews or 
listing actions. We anticipate coordinating with the Park Service, 
USGS, universities, and other interested entities that may be able to 
contribute funding or resources to assist the Park Service in their 
efforts to monitor this species, thereby providing the information 
necessary to determine whether protections under the Act should be 
reinstated. The post-delisting monitoring plan includes measures to: 
Monitor recreation traffic in Eureka Valley; maintain a Remote 
Automated Weather Station in Eureka Valley; and continue annual 
population monitoring. The annual population monitoring will be based 
on a subsampling methodology, first implemented in the spring of 2017, 
and will also include observations of any damage to Eureka Valley 
evening-primrose resulting from recreation or herbivory.
    Given the mission of the Park Service and its past and current 
stewardship efforts, it is important to note that management for Eureka 
Valley evening-primrose has been effective to date, and it is 
reasonable to expect that management will continue to be effective for 
Eureka Valley evening-primrose and its habitat beyond a post-delisting 
monitoring period, the 20-year timeframe associated with the Wilderness 
and Backcountry Stewardship Plan (Park Service 2013b), and well into 
the future. In addition to post-delisting monitoring, the Park Service 
anticipates continuing to manage the Eureka Valley dunes, including 
such tasks as conducting ranger patrols, maintaining educational signs, 
and making contact with visitors within the range of the species (Cipra 
in litt. 2013). Additional monitoring or research (beyond post-
delisting monitoring requirements) may occur in the future for Eureka 
Valley evening-primrose and other rare endemics within the Park based 
on congressional funding and resource levels (Cipra in litt. 2013). We 
will work closely with the Park Service to ensure post-delisting 
monitoring is conducted and to ensure future management strategies are 
implemented (as warranted) to benefit Eureka Valley evening-primrose.

Summary of Comments and Recommendations

    In the proposed rule published on February 27, 2014, in the Federal 
Register (79 FR 11053), we requested that all interested parties submit 
written comments on the proposal by April 28, 2014. We also contacted 
appropriate Federal and State agencies, scientific experts and 
organizations, and other interested parties and invited them to comment 
on the proposal. We did not receive any requests for a public hearing. 
All substantive information provided during the comment period has 
either been incorporated directly into this final determination or is 
addressed below.

Peer Reviewer Comments

    In accordance with our peer review policy published on July 1, 1994 
(59 FR 34270), we solicited expert opinion from five knowledgeable 
individuals with scientific expertise that included familiarity with 
Eureka Valley evening-primrose, Eureka dune grass, their habitat, 
biological needs and potential threats, or principles of conservation 
biology. We received responses from all five of the peer reviewers.
    We reviewed all comments received from the peer reviewers for 
substantive issues and new information regarding the proposed delisting 
of Eureka Valley evening-primrose and Eureka dune grass. The peer 
reviewers provided additional information, clarifications, and 
suggestions to improve the final rule. Peer reviewer comments are 
addressed in the following summary, and new information was 
incorporated into the final rule as appropriate.
    For Eureka Valley evening-primrose, one peer reviewer cautioned 
that our proposed delisting was based on current and reasonably 
predicted conditions. A second peer reviewer expressed concern related 
to the potential of future rainfall decline and possible competition 
with Russian thistle. A third peer reviewer expressed concerns 
regarding potential climate change effects into the future. And a 
fourth peer reviewer suggested that we need additional information to 
support our conclusions on herbivory, competition with Russian thistle, 
and effects of climate change.
    For Eureka dune grass, three peer reviewers expressed concerns 
based on potential effects related to climate change (changes in 
rainfall), infrequent germination and establishment, declining numbers 
of plants at two of three populations, herbivory, and low genetic 
diversity. Another peer reviewer suggested that herbivory and 
competition with Russian thistle are potential threats to Eureka dune 
grass and that we needed to continue to monitor impacts of these 
stressors as well as the effects of climate change. Overall, peer 
reviewers suggested that stressors to Eureka dune grass were more 
severe than our analysis indicated.
    We have addressed specific peer review comments below in the 
following order: Comments of a general nature or applicable to both 
species, comments specific to Eureka Valley evening-primrose, and 
comments specific to Eureka dune grass.
Peer Reviewer Comments of a General Nature or Applicable to Both 
Species
    (1) Comment: Three peer reviewers commented on competition with 
Russian thistle as a potential threat to Eureka Valley evening-
primrose, Eureka dune grass, or both. Of these three, one expressed 
concern that Russian thistle was a potential threat to Eureka Valley 
evening-primrose. Additionally, one peer reviewer stated there was 
insufficient information to reach a conclusion regarding Eureka Valley 
evening-primrose and Russian thistle, and another suggested we further 
evaluate competition with Russian thistle as a potential stressor for 
both species. The latter peer reviewer provided information concerning 
the spread of Russian thistle over time on another desert dune system 
(in Petrified Forest National Park (PFNP), Arizona (Thomas et al. 
2009)).
    Our Response: Our analysis used the best available information in 
analyzing the potential threat posed to Eureka Valley evening-primrose 
and Eureka dune grass by competition with Russian thistle. In this 
final rule, we provided additional information regarding potential 
competition between the plants and Russian thistle (see ``Competition 
With Russian Thistle'' sections above for both Eureka Valley evening-
primrose and Eureka dune grass for additional discussion). The results 
of one study (Chow and Klinger 2014, 2016) elucidated that, in a 
nursery setting, Eureka Valley evening-primrose was more competitive 
with itself than it was with Russian thistle, and Park staff observed 
differences in growing season phenology that would minimize competition 
in the field between the two species (Park Service 2015). In addition, 
we concluded that Russian thistle is not likely having a population-
level impact on the Eureka Valley evening-primrose, which is a longer 
lived perennial species with a seedbank

[[Page 8598]]

and a means of going into dormancy and lasting through unfavorable 
years. By contrast, Russian thistle is an annual species with a short-
lived seedbank. See the ``Competition with Russian Thistle'' section 
under Eureka Valley evening-primrose, above, for further discussion.
    We are aware of no studies that have focused on potential 
competition between Russian thistle and Eureka dune grass, and there 
are only a few studies that have looked at competition between Russian 
thistle and other grass species. The USGS study (Scoles-Sciulla and 
DeFalco 2016) found that rooting depths for established Eureka dune 
grass individuals were deeper than those typical of Russian thistle, 
which would also serve to minimize competition. In addition, the dune 
grass also occupies a higher elevation compared to where Russian 
thistle occurs. Thus, at this time, we have determined that Russian 
thistle is not a threat to either species (see ``Competition With 
Russian Thistle'' sections, above, for both Eureka Valley evening-
primrose and Eureka dune grass for additional discussion).
    (2) Comment: One peer reviewer asserted we made a premature 
conclusion that Russian thistle was not a threat to Eureka Valley 
evening-primrose and Eureka dune grass, suggesting there may be an 
interaction between Russian thistle and lagomorph abundance. The peer 
reviewer provided additional information regarding lagomorph 
populations and Russian thistle that was not considered in the proposed 
rule (see, for instance, Daniel et al. 1993, and Fagerstone et al. 
1980). The peer reviewer indicated that Russian thistle may have 
increased lagomorph abundance and thus an increased level of herbivory 
on both species. The peer reviewer recommended that we collect 
information on the demography of the black-tailed jackrabbits in 
relationship to Russian thistle infestations and levels of herbivory 
and the reproductive success of Eureka Valley evening-primrose and 
Eureka dune grass.
    Our Response: In both the proposed rule and in response to the 
information provided by the peer reviewer, we considered the 
interaction between Russian thistle and lagomorph populations. Although 
we have no information regarding lagomorph populations on the dunes in 
Eureka Valley and how their abundance may be influenced by Russian 
thistle, we incorporated the new information provided by the peer 
reviewer into the final rule and discussed the combination of Russian 
thistle and lagomorphs as a potential threat to Eureka Valley evening-
primrose and Eureka dune grass (see ``Competition With Russian 
Thistle'' sections, above, for both Eureka Valley evening-primrose and 
Eureka dune grass for additional discussion). We have forwarded the 
recommendation to investigate demography of black-tailed jackrabbits in 
relationship to Russian thistle infestations and levels of herbivory on 
the two plants species to the Park Service.
    (3) Comment: Two peer reviewers suggested we conduct additional 
analyses on the potential effects of climate change on Eureka Valley 
evening-primrose and Eureka dune grass and continue to monitor their 
populations to assess the effects of herbivory and competition with 
Russian thistle. A third peer reviewer suggested that we defer our 
determination until USGS completes its study of these two species.
    Our Response: We appreciate the peer reviewers' recommendations 
regarding additional analyses and monitoring; however, we are unable at 
this time to defer our determination until a later date. Our analysis 
of the various stressors and our final agency action has been guided by 
the Act and its implementing regulations, considering the five listing 
factors and using the best available information, as per our policy on 
Information Standards under the ESA (59 FR 34271, July 1, 1994). 
Although we are not proceeding with a final delisting rule for Eureka 
dune grass at this time, we have shared the peer reviewer's 
recommendations for future monitoring with staff from Death Valley 
National Park for their consideration.
    (4) Comment: One peer reviewer provided recommendations regarding 
future monitoring of both species. The peer reviewer recommended 
monitoring OHV activity, discussed how to improve upon the current 
monitoring strategy, and suggested an appropriate model to analyze 
data.
    Our Response: We appreciate the peer reviewer's recommendations 
regarding future monitoring of Eureka Valley evening-primrose and 
Eureka dune grass, and the suggested model to use for analyzing the 
data. We agree that selecting the appropriate model for data analysis 
is important because even with data gathered over the last 5 years, it 
has been difficult to detect population trends. We shared the peer 
reviewer's recommendations for future monitoring with staff from Death 
Valley National Park for their consideration. The monitoring outlined 
in the post-delisting monitoring plan for the Eureka Valley evening-
primrose will include notation of any observed impacts, including OHV 
activity, to the species if they occur.
Peer Reviewer Comments Specific to Eureka Valley Evening-Primrose
    (5) Comment: One peer reviewer expressed concerns about seed 
predation and herbivory impacts to Eureka Valley evening-primrose, 
stating that if herbivory impacts are high on an individual, the 
individual would not produce seed before succumbing to predation 
impacts, potentially resulting in a net loss of seed bank. 
Alternatively, another peer reviewer asserted that seed predation and 
herbivory were not significant threats to Eureka Valley evening-
primrose, although no information was provided to support this view.
    Our Response: Based on observations made by USGS researchers 
(Scoles-Sciulla and DeFalco 2013) and University of California-Davis 
(Chow and Klinger 2013a), there is information to indicate that 
herbivory, particularly by lagomorphs, is a stressor for Eureka Valley 
evening-primrose, at least in those portions of the dunes where such 
herbivory has been observed. In contrast to Eureka dune grass, Eureka 
Valley evening-primrose has two reproductive strategies that provide 
resilience in the face of herbivory: First, it produces large amounts 
of seed, so that even if the population sustains some impact from seed 
herbivory, it has a mechanism for replacing itself over time through 
the seedbank; second, individuals are able to regenerate vegetatively 
through the development of clonal rosettes. Although we acknowledge 
that any stress caused by loss of biomass due to herbivory could place 
additional stress on individual plants and limit their ability to 
expend resources on reproduction, the best available information 
indicates that the life-history strategies of this species serve to 
counteract the effects of herbivory such that herbivory does not 
significantly affect the viability of the species, or its ability to 
respond to favorable conditions for germination, growth, and 
reproduction when they occur.
    (6) Comment: One peer reviewer stated that the effects of climate 
change was a threat to Eureka Valley evening-primrose, asserting that 
climate change would lead to increased drought stress, and that we did 
not provide evidence to support our conclusion that Eureka Valley 
evening-primrose possesses adaptations that would allow it to persist 
into the future. The peer reviewer also provided climate envelope 
forecasts for Eureka Valley evening-primrose, using species locality 
data, climate layers from the IPCC fifth

[[Page 8599]]

assessment report's Coupled Model Intercomparison Project Phase 5 
(CMIP5), and Maxent. The peer reviewer claimed that the results of this 
information and modeling exercise indicate that the species is 
projected to disappear from the Main Dunes by approximately 2050. The 
peer reviewer also stated that Eureka Valley evening-primrose is a 
microendemic, which, by definition, is found only at one or a very 
small number of locations. Furthermore, the peer reviewer declared that 
when the climate changes at that one or few locations, species are at 
risk of falling outside of their climatic envelope, or are at risk of 
extinction.
    Our Response: We appreciate the work the peer reviewer did to 
develop a climate envelope forecast for this species. With respect to 
adaptations, we discussed in the proposed delisting rule that the 
phenology of Eureka Valley evening-primrose makes it likely to have 
high germination, recruitment, and reproduction in El Ni[ntilde]o years 
when winter rainfall is above average (see the sections on Species 
Description, Taxonomy, and Life History in the proposed rule). In the 
proposed rule to delist, we concluded that a shift in climatic norms 
will likely cause stress to Eureka Valley evening-primrose. 
Furthermore, we stated that the best available information indicated 
that the species is physiologically adapted to the specific hydrologic 
and soil conditions on the dunes, and the stress imposed by projected 
climate change effects currently and in the future is not likely to 
rise to the level that the long-term persistence of Eureka Valley 
evening-primrose would be impacted.
    Based on the new and clarifying information we received, we 
conclude that of all the potential future stressors on Eureka Valley 
evening-primrose, a shift in climatic norms may be important in 
affecting its long-term persistence. We note that, as a short-lived 
perennial, the ability of this species to shift geographically over 
time with shifting climatic norms is greater than would be for a long-
lived perennial plant species. However, because of the uncertainty 
regarding the magnitude and the imminence of such a shift, we are 
unable to determine the extent that this may become a stressor in the 
foreseeable future. Because climate change science is a rapidly 
evolving field, we updated our climate change discussion in this final 
rule to include information from more recent modeling efforts for the 
southwest region. As one of the measures in the post-delisting 
monitoring plan, the Park Service will continue to track seasonal 
rainfall from local weather stations and observe annual patterns of 
correlation between amount of rainfall and expression of Eureka Valley 
evening-primrose.
    (7) Comment: One peer reviewer stated that stochastic events were 
not a significant threat, although no information was provided or 
discussed to support this position. Two other peer reviewers discussed 
how the life history of Eureka Valley evening-primrose affects 
population persistence in response to stochastic events. Both of these 
peer reviewers agreed that the long-lived seed bank of Eureka Valley 
evening-primrose and its ability to form clones help to ensure the 
long-term viability of this species. However, one of these peer 
reviewers thought population persistence could be impacted by mass 
germination events and herbivores through a reduction of the seed bank.
    Our Response: We agree that the ability of Eureka Valley evening-
primrose to persist in the face of stochastic events (in addition to 
other potential stressors) is in part dependent on the life-history 
characteristics of the species (see the ``Life History'' sections on 
Eureka Valley evening-primrose above and in the proposed delisting 
rule). The copious seed production of individuals (and formation of 
seed bank), once they are established, works in favor of long-term 
persistence even in the face of stochastic events, as does the species' 
ability to establish many new individuals (mass establishment) when 
conditions are favorable. The best available information indicates that 
current and projected future impacts associated with stochastic events 
(with the exception of extreme weather events) are not likely to rise 
to the level that the long-term persistence of Eureka Valley evening-
primrose would be impacted. The National Park Service will continue to 
monitor the status of Eureka Valley evening-primrose populations into 
the future (for 10 years) as a means of determining whether any 
potential stressors, including stochastic events, are impacting the 
species (see ``Post-Delisting Monitoring Plan--Oenothera californica 
ssp. eurekensis,'' above).
Peer Reviewer Comments Specific to Eureka Dune Grass
    (8) Comment: Two peer reviewers commented on seed predation and 
herbivory as potential threats to Eureka dune grass. One of these peer 
reviewers provided information on how herbivory could impact sensitive 
plant species by reducing their seed production. The other peer 
reviewer asserted that seed predation and herbivory were not 
significant threats to Eureka dune grass.
    Our Response: Based on observations made by USGS researchers 
(Scoles-Sciulla and DeFalco 2013) and a researcher from the University 
of California-Davis (Chow 2012b), there is information to indicate that 
herbivory, particularly by lagomorphs, is affecting Eureka dune grass, 
at least in those portions of the dunes where such herbivory has been 
observed. Given that Eureka dune grass is already experiencing low to 
no reproduction, any additional loss of biomass due to herbivory will 
likely place additional stress on individual plants and limit their 
ability to expend resources on reproduction. However, based on the best 
available information at this time, we concluded that the observed 
impacts from herbivory, by themselves, are not causing population- or 
rangewide-level effects for the Eureka dune grass. We acknowledge that 
herbivory could be a concern for a species that has low recruitment and 
apparent declines, and recommend that observations on the extent of 
herbivory should continue to be made in the future.
    (9) Comment: Two peer reviewers asserted that climate change is a 
threat to Eureka dune grass. One of these peer reviewers indicated that 
climate change would lead to increased drought stress and stated that 
we did not provide evidence to support our conclusion that Eureka dune 
grass possesses adaptations that allow this species to persist into the 
future. Both peer reviewers also stated that climate change may cause 
reductions in rainfall or changes in rainfall patterns, which could 
affect germination and establishment of Eureka dune grass. For 
instance, one peer reviewer provided summer precipitation data showing 
that over the last 15 years, there were fewer years of above-average 
summer rainfall (required for the germination of Eureka dune grass) as 
compared to the previous 15-year period, and thus indicating that 
current climatic weather patterns are not conducive to the germination 
events needed for long-term persistence of the species.
    Our Response: We appreciate the analysis of summer precipitation 
rainfall data provided by one of the peer reviewers. Previous research 
also indicates that summer precipitation is likely critical for the 
germination of Eureka dune grass (Pavlik and Barbour 1986, pp. 11, 47-
59). Although the correlation shown by the new precipitation data 
provided by the peer reviewer does not prove causation, given what we 
know about the life-history characteristics of this species, we agree 
it is reasonable to assume the lack of summer precipitation is one of

[[Page 8600]]

the parameters affecting the ability of Eureka dune grass to experience 
germination events. Since February 2014 when our proposed rule 
published, Park staff were able to observe several patches of 
germination of Eureka dune grass, particularly on the west side of 
Saline Spur Dunes and the northwest end of Main Dunes in the fall of 
2015. Park staff were unable to monitor these germinants over time, and 
thus, we have no information on whether these germinants may have 
successfully recruited into the population.
    In the proposed rule to delist, we concluded that a shift in 
climatic norms will likely cause stress to Eureka dune grass (79 FR 
11067-11069, February 27, 2014). Furthermore, we stated that the best 
available information currently indicated that this species was 
physiologically adapted to the specific hydrologic and soil conditions 
on the dunes, and the stress imposed by projected climate change 
effects currently and in the future is not likely to rise to the level 
that the long-term persistence of Eureka dune grass would be impacted.
    Based on the new and clarifying information we received, it is 
possible that of all the potential future stressors on Eureka dune 
grass, a shift in climatic norms may be important in affecting its 
long-term persistence. We note that, as a long-lived perennial, the 
ability of this species to shift geographically over time with shifting 
climatic norms is less than would be for a short-lived perennial or 
annual plant species. However, because of the uncertainty regarding the 
magnitude and the imminence of such a shift, we are unable to determine 
the extent that this may become a stressor in the foreseeable future. 
Given the modeled predictions of a continued changing climate in this 
region, this potential stressor should continue to be monitored and 
evaluated in the future. However, we did conclude that climate-related 
impacts may be acting in concert with other stressors to contribute to 
the decrease in population numbers and distribution for Eureka dune 
grass. We also note that continuing to track seasonal and annual 
rainfall from local weather stations will be a part of the ongoing 
population monitoring for this species.
    (10) Comment: Two peer reviewers suggested that the monitoring data 
collected by the Park Service, specifically distribution data and 
repeat photopoints, indicated that Eureka dune grass has experienced a 
decline throughout its range. One peer reviewer thought we should 
extrapolate the results from repeat transects and photopoints rather 
than assume Eureka dune grass has experienced declines only in these 
specific areas. This peer reviewer also noted that Eureka dune grass 
has a small range despite our assertion that it continues to occupy 
almost the same geographic area it did at the time of listing. 
Additionally, the peer reviewer stated that Eureka dune grass has very 
low population numbers, and few, if any, plants have been recruited 
into the population since 1999.
    Our Response: Recent survey information from the Park Service 
indicates that, although the rangewide distribution of Eureka dune 
grass continues to be similar over the years when observed at a large 
scale (e.g., it continues to occur scattered across the entirety of all 
three dunes), the large-scale monitoring (1-ha grid system) has not 
been as effective in detecting changes in abundance in smaller, 
localized areas. Such changes are more readily observed with smaller-
scale monitoring techniques, such as the photopoint monitoring and the 
mapping of individual clumps over time. The declines in the number of 
Eureka dune grass clumps are shown in repeat photopoints at both Eureka 
and Marble Canyon Dunes.
    As of 2017, there are two additional years of Park Service data 
from the rangewide distribution monitoring grid that show continuing 
declines at the Main Dunes and Marble Canyon Dunes. This distribution 
data, combined with recent photopoint survey information from the Park 
corroborates that the declines documented at both Eureka and Marble 
Canyon Dunes are likely representative of rangewide impacts. Because 
the Main Dunes support over half the Eureka dune grass, the decline in 
abundance and density on that dune is relatively more important for the 
species.
    (11) Comment: One peer reviewer stated that there was a low degree 
of evolutionary potential within and between populations of Eureka dune 
grass based on the available genetic information (low levels of allelic 
variation relative to other grass taxa).
    Our Response: We acknowledge the low levels of allelic variation 
found, as per Bell (2013). However, Eureka dune grass has persisted for 
a long evolutionary time. While it is possible that low allelic 
variation may contribute to the demographic characteristics, we do not 
know to what extent that may affect the species' fitness.
    (12) Comment: One peer reviewer stated that stochastic events (for 
instance, a spring wind storm that would desiccate new germinants) are 
a potential threat to Eureka dune grass. The peer reviewer indicated 
that the ability of the Eureka dune grass population to persist was 
dependent upon mass establishment events from seed and the longevity of 
adult plants. Furthermore, based on recent climate analyses, the peer 
reviewer asserted that the frequency of conditions thought to be 
suitable for mass establishment events is apparently decreasing, noting 
that there have not been any mass establishment events since 1984-1985.
    Our Response: We agree with the peer reviewer that the ability of 
Eureka dune grass to persist in the face of stochastic events (in 
addition to other stressors) is in part dependent on the life-history 
characteristics of the species. The longevity of individuals, once they 
are established, works in favor of long-term persistence even in the 
face of stochastic events, as does its ability to establish many new 
individuals (mass establishment) when conditions are favorable. Future 
monitoring of the patches of germination observed by Park staff in fall 
2015 will be useful to add to our knowledge of recruitment potential 
that follows from a germination event.

Comments From the State

    Section 4(b)(5)(A)(ii) of the Act states that the Secretary must 
give actual notice of a proposed regulation under section 4(a) to the 
State agency in each State in which the species is believed to occur, 
and invite the comments of such agency. Section 4(i) of the Act states, 
``the Secretary shall submit to the State agency a written 
justification for his failure to adopt regulations consistent with the 
agency's comments or petition.'' The Service submitted the proposed 
regulation to the State of California but received no formal comments 
from the State regarding the proposal.

Public Comments

    We received five letters from the public that provided comments on 
the proposed rule. All five commenters stated that Eureka dune grass 
did not warrant delisting. Four of these commenters maintained that 
Eureka Valley evening-primrose did not warrant delisting, and cited 
continuing concerns with unauthorized OHV use and competition with 
nonnative species. The fifth suggested the species may warrant either 
downlisting or delisting, stating that the most recent data indicated a 
general increasing trend, albeit episodic, despite significant 
herbivory.

[[Page 8601]]

Public Comments of a General Nature or Applicable to Both Species

    (13) Comment: One commenter indicated that the Park Service's 
monitoring program has demonstrated that threats still exist for Eureka 
Valley evening-primrose and Eureka dune grass. The commenter asserted 
that we were ignoring threats information and proposing to delist the 
Eureka Valley evening-primrose and Eureka dune grass because they were, 
at one time, considered ``Spotlight Species.''
    Our Response: In 2008, as part of a nationwide initiative, we 
identified Eureka Valley evening-primrose and Eureka dune grass as 
``Spotlight Species''; this initiative was intended to set performance 
targets and identify actions to achieve those targets for the 
spotlighted species. We developed 5-year Spotlight Species Action Plans 
for each species and identified specific goals, measures, and actions; 
the goal was to delist or downlist the species. The 2010 Spotlight 
Species Action Plans themselves did not influence our decision when 
evaluating the status of the species. As with all listed species, we 
conduct a thorough review of the best available scientific and 
commercial information and determine whether the threats to the species 
have been eliminated or reduced to the point that the species no longer 
meets the definition of an endangered species or a threatened species 
under the Act.
    (14) Comment: Three commenters suggested that there is inadequate 
information to conclude that Russian thistle is not competing with 
Eureka Valley evening-primrose and Eureka dune grass given the limited 
water and nutrients available; they suggested further study is 
warranted to determine the potential impact. One of these commenters 
cited a study (Cannon et al. 1995) that found Russian thistle impacted 
grassland succession.
    Our Response: Please refer to Comment and Response (1) above.
    (15) Comment: There were numerous comments regarding the potential 
impacts of OHV use on the two plants. For instance, three commenters 
asserted that impacts from unauthorized recreational activities, 
specifically OHV use, continue to represent a threat to Eureka Valley 
evening-primrose and Eureka dune grass. One of these commenters and a 
fourth commenter suggested there is a need for additional interpretive 
and directional signage, as well as ongoing monitoring and enforcement. 
Further, one of these commenters stated that unauthorized OHV activity 
may increase on and around the Eureka Dunes due to decreasing resources 
for Park Service law enforcement. One commenter asserted that we should 
not delist Eureka Valley evening-primrose or Eureka dune grass because 
there remains a low level of unauthorized OHV use in these species' 
habitat, and the Eureka Valley evening-primrose and Eureka dune grass 
populations have failed to respond positively to current management.
    Our Response: In the proposed rule and in this final rule, we 
acknowledge that unauthorized OHV use continues; however, we conclude 
that, based on the best available information, this unauthorized 
activity occurs sporadically, and does not appear to be having a 
population-level impact on either species. We disagree that Eureka 
Valley evening-primrose has not responded positively to BLM's and the 
Park Service's management of the area. Most notably, both agencies have 
taken steps to protect Eureka Valley from unauthorized recreational 
activities, especially OHV use. Prior to these efforts, unrestricted 
OHV use occurred throughout Eureka Valley, concentrated on and around 
the Main Dunes. Additionally, the monitoring program developed by the 
Park Service has demonstrated that, though the Eureka Valley evening-
primrose population fluctuates in above-ground expression, it continues 
to be distributed throughout its known range. For example, in 2014, the 
Park Service documented the largest expression of Eureka Valley 
evening-primrose ever observed.
    Although monitoring the status of Eureka dune grass has been more 
challenging over time, the Park Service has, since 2007, documented a 
larger geographic distribution for the species than was known 
previously. Monitoring also indicates that, while the density of Eureka 
dune grass has declined across much of its range (including the Main 
Dunes that harbor the majority of the species' range), there are 
certain small areas where density has increased. Overall, the current 
level of unauthorized OHV use is sporadic and does not occur across the 
range of the species, and there does not appear to be any correlation 
between OHV recreation and the status of the species. In addition, we 
consider the Park Service's current efforts adequate to monitor and 
enforce closures in the Eureka Valley, and we anticipate that these 
efforts will continue into the future. Therefore, we conclude it is 
likely that there are other factors that are affecting the status of 
Eureka dune grass, rather than management efforts on behalf of the Park 
Service.
    (16) Comment: One commenter stated that the recovery of Eureka 
Valley evening-primrose and Eureka dune grass depends on the long-term 
commitment of the Park Service to conduct monitoring and management, 
including enforcement of closures to OHV use and other recreational 
impacts, management of Russian thistle, continued population 
monitoring, and additional research. Another commenter suggested that 
it was premature to delist Eureka dune grass until USGS completed their 
study. The second commenter noted that despite Eureka dune grass 
occurring within a federally designated wilderness, the population 
continues to decline, and additional research is necessary to determine 
the reasons for this decline.
    Our Response: The Park Service has demonstrated its commitment to 
continue monitoring and protecting the populations of Eureka Valley 
evening-primrose and Eureka dune grass, and has worked with us to 
develop a post-delisting monitoring plan for Eureka Valley evening-
primrose. Additionally, under the Act, we are tasked with using the 
best available information, and at this time, while the information 
generated by the USGS study may be useful, we cannot delay our 
determination until this or additional studies are completed.
    (17) Comment: One commenter stated that we should discuss how the 
removal of either or both species from the Act may impact the 
availability and allocation of funding for enforcement of the Park 
Service regulations and patrols of Eureka Valley under Factor D. The 
commenter stated that the designation under the Act provides a level of 
protection by mandating that the Park Service maintain monitoring, 
patrols, and enforce existing regulations, and also protect the 
ecosystem.
    Our Response: Under the Act, we determine whether a species is an 
endangered species or threatened species because of any of five listing 
factors. We evaluate the impacts of current and future stressors acting 
on the species and habitat where it occurs and any conservation 
measures or regulatory mechanisms that may offset those impacts. The 
Eureka Valley evening-primrose and Eureka dune grass occur entirely 
within Eureka Valley, which is managed by the Park Service. We 
concluded in the proposed rule and reaffirm here that the Park 
Service's laws, policies, and plans will continue to protect the 
habitat of Eureka Valley evening-primrose and Eureka dune grass, and 
effectively minimize those stressors described under Factors A, B, and 
E (specifically in relation to OHV

[[Page 8602]]

activities). Additionally, the Park Service plans to continue 
monitoring both species.
    (18) Comment: One commenter indicated that coyote poaching, 
specifically at the Ash Meadows National Wildlife Refuge, was a 
potential factor affecting lagomorph (Lepus and Sylvilagus) populations 
and leading to increased herbivory of rare plants. However, the 
commenter noted that because Eureka Valley is remote, poaching may not 
be a factor that affects levels of herbivory experienced by Eureka 
Valley evening-primrose or Eureka dune grass.
    Our Response: We acknowledge that a reduction in the number of 
predators such as coyotes could lead to an increase in lagomorph 
numbers, and we appreciate the commenter submitting this information. 
However, our evaluation of the best available information at this time 
does not indicate that coyote poaching has occurred or is occurring in 
Eureka Valley.
Public Comments Specific to Eureka Valley Evening-Primrose
    (19) Comment: One commenter asserted that the evidence provided in 
the proposed delisting rule supported downlisting of Eureka Valley 
evening-primrose. However, the commenter expressed concern that 
herbivory and unauthorized recreational activities still pose a threat 
to important population sites, such as the occurrence located to the 
east of the Main Dunes.
    Our Response: In the proposed rule, we concluded that herbivory and 
unauthorized recreational activities, specifically OHV use, were not 
threats to the Eureka Valley evening-primrose. While we acknowledge 
that unauthorized recreational activities do occur on a sporadic basis, 
we concluded that these activities were limited in extent. We also 
received new information from the Park Service in 2014 indicating there 
was another mass germination of Eureka Valley evening-primrose in the 
sand flats to the east of the Main Dunes, including observations of the 
species in locations that it previously had not been documented (Park 
Service 2014). This new information indicates that Eureka Valley 
evening-primrose maintains a large seedbank, and when conditions are 
favorable, it can result in mass germination events. While we do not 
know how many of these seedlings will be recruited into the population, 
if even a portion of the seedlings survive to become adults, this will 
help to maintain the viability of this population. Finally, we 
acknowledge that herbivory could have significant impacts on 
individuals in certain years when the Eureka Valley evening-primrose 
population is small. However, we anticipate that the life-history 
characteristics of this species (e.g., abundant and precocious seed 
production, production of clones to spread risk, a portion of the 
population remains dormant) help to maintain its viability despite 
years when herbivory is high.
Public Comments Specific to Eureka Dune Grass
    (20) Comment: Four commenters questioned why we proposed to delist 
Eureka dune grass given the Park Service's information indicating 
portions of the populations at Main and Marble Canyon Dunes have 
declined. Some of these commenters acknowledged that recent surveys 
(2008 to 2013) indicated populations at Marble Canyon and Saline Spur 
Dunes were stable. However, all four commenters also noted that none of 
the populations showed a statistically significant net increase in 
population size over the same time period, and that long-term data 
(i.e., repeat photopoints) demonstrated local extirpations have 
occurred at Main and Marble Canyon Dunes. Two commenters argued that 
monitoring by the Park Service indicates that Eureka dune grass 
continues to decline at the Main Dunes, which contains the largest 
segment of the population. Finally, one commenter indicated that we did 
not provide an explanation why the declines we described were not 
significant. This commenter also stated that we did not explain why 
large reproductive plants had died or why they have not been replaced 
by seedlings and young plants.
    Our Response: Please refer to Comment and Response (10) above.
    (21) Comment: One commenter asserted that the low density of Eureka 
dune grass plants is due to several factors, such as water and nutrient 
availability, and inability of individuals to become established on the 
steepest slopes. The commenter also highlighted specifics about the 
Main Dunes that we should take into consideration, i.e., that the Main 
Dunes are much larger than Marble Canyon and Saline Spur Dunes, and 
that the majority of Eureka dune grass individuals occur on the Main 
Dunes.
    Our Response: We added language into this final rule to indicate 
several factors that may limit the distribution of Eureka dune grass 
across its range. We provided population estimates for all three dunes 
in the Abundance Surveys and Population Estimates section, above, for 
Eureka dune grass. The size of the three dunes is also described in 
``Environmental Setting'' section of the Background Information 
document (Service 2014, pp. 4-5), and we noted that the Main Dunes was 
the largest with the largest population of Eureka dune grass. Overall, 
following our evaluation of comments and new information received since 
the time of the proposal, we conclude that a combination of factors are 
likely contributing to Eureka dune grass lowered abundance and density. 
Thus, we have determined that although the species is not currently in 
danger of extinction (endangered), it may become so in the foreseeable 
future (threatened). See the Summary of the Determination for Eureka 
Dune Grass section, above.
    (22) Comment: Two commenters questioned our determination that the 
effects of climate change were not a threat now or in the future to 
Eureka dune grass. The first commenter indicated that prolonged drought 
could impact the Eureka dune grass population due to the loss of adult 
plants, and the failure of seeds to become established. The second 
commenter argued that, while the exact impacts to Eureka dune grass are 
unclear, scientific models indicate that the Mojave Desert will become 
hotter and drier. Additionally, this commenter argued that these 
changing conditions may exceed the physiological tolerance of the 
species, and lead to decreases in plant density and a range 
contraction.
    Our Response: Please refer to Comment and Response (9), above.
    (23) Comment: One commenter argued that the best available 
information indicates Eureka dune grass has low genetic diversity, 
which increases its vulnerability to changes in the environment and 
increases its risk of extinction. The commenter also stated that low 
genetic diversity may be a factor in the low seed production and 
infrequent establishment of Eureka dune grass.
    Our Response: Please refer to Comment and Response (11), above.
    (24) Comment: One commenter referenced recent information collected 
by USGS on the amount of herbivory occurring on Eureka dune grass. The 
commenter acknowledged that the amount of herbivory experienced by 
plants varies with the number of herbivores; however, the commenter 
indicated that a combination of high levels of herbivory (as documented 
by USGS) and Eureka dune grass' life-history characteristics (e.g., low 
annual seed production, no vegetative reproduction, and infrequent 
germination and establishment of

[[Page 8603]]

seedlings) could affect the long-term persistence and recovery of the 
population.
    Our Response: Please refer to Comment and Response (8) above.
    (25) Comment: Three commenters claimed that Recovery Plan 
objectives 1 and 2 (Service 1982, pp. 26-31) have not been met for 
Eureka dune grass, and thus, the species should not be delisted. These 
commenters argued that we failed to consider evidence that indicates 
the population of Eureka dune grass continues to decline at several 
locations throughout its range, especially at the most dense occurrence 
at the northern end of the Main Dunes. One of these commenters 
indicated that despite the reduction in unauthorized OHV activity, the 
Eureka dune grass population continues to decline. This commenter 
suggested the continued population decline may be the result of impacts 
from past OHV activity, or due to other factors. Finally, two 
additional commenters suggested that we postpone making a decision 
until USGS completes its study.
    Our Response: For our discussion of the Recovery Plan Objectives, 
please refer to the Recovery and Recovery Plan Implementation section, 
above. While we agree the information generated by the USGS study may 
be useful, we cannot delay our determination until this study is 
completed. We note that any additional information forthcoming from 
current studies can be incorporated into monitoring efforts that will 
be continued by the Park Service.

Required Determinations

National Environmental Policy Act (42 U.S.C. 4321 et seq.)

    We have determined that environmental assessments and environmental 
impact statements, as defined under the authority of the National 
Environmental Policy Act, need not be prepared in connection with 
listing, delisting, or reclassification of a species as an endangered 
or threatened species under the Endangered Species Act. We published a 
notice outlining our reasons for this determination in the Federal 
Register on October 25, 1983 (48 FR 49244).

References Cited

    A complete list of all references cited in this rulemaking is 
available on the internet at http://www.regulations.gov under Docket 
No. FWS-R8-ES-2013-0131 or upon request from the Deputy Field 
Supervisor, Carlsbad Fish and Wildlife Office (see FOR FURTHER 
INFORMATION CONTACT).

Authors

    The primary authors of this final rule are staff members of the 
Pacific Southwest Regional Office in Sacramento, California, in 
coordination with the Ventura Fish and Wildlife Office in Ventura, 
California, and the Carlsbad Fish and Wildlife Office in Carlsbad, 
California.

List of Subjects in 50 CFR Part 17

    Endangered and threatened species, Exports, Imports, Reporting and 
recordkeeping requirements, Transportation.

Regulation Promulgation

    Accordingly, we hereby amend part 17, subchapter B of chapter I, 
title 50 of the Code of Federal Regulations, as set forth below:

PART 17--ENDANGERED AND THREATENED WILDLIFE AND PLANTS

0
1. The authority citation for part 17 continues to read as follows:

    Authority:  16 U.S.C. 1361-1407; 1531-1544; and 4201-4245, 
unless otherwise noted.

0
2. Amend Sec.  17.12(h), the List of Endangered and Threatened Plants, 
under FLOWERING PLANTS, by:
0
a. Removing the entry for ``Oenothera avita ssp. eurekensis''; and
0
b. Revising the entry for ``Swallenia alexandrae'' to read as set forth 
below.


Sec.  17.12   Endangered and threatened plants.

* * * * *
    (h) * * *

----------------------------------------------------------------------------------------------------------------
                                                                                               Listing citations
        Scientific name            Common name             Where listed             Status       and applicable
                                                                                                     rules
----------------------------------------------------------------------------------------------------------------
       Flowering Plants
 
                                                  * * * * * * *
Swallenia alexandrae..........  Eureka dune        Wherever found..............  T             82 FR [Federal
                                 grass, Eureka                                                  Register page
                                 Valley dune                                                    where the
                                 grass, or Eureka                                               document
                                 dunegrass.                                                     begins],
                                                                                                February 27,
                                                                                                2018.
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------


    Dated: December 3, 2017.
James W. Kurth
Deputy Director for U.S. Fish and Wildlife Service Exercising the 
Authority of the Director for U.S. Fish and Wildlife Service.
[FR Doc. 2018-03769 Filed 2-26-18; 8:45 am]
 BILLING CODE 4333-15-P