[Federal Register Volume 76, Number 138 (Tuesday, July 19, 2011)]
[Proposed Rules]
[Pages 42654-42658]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-17864]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R2-ES-2011-0044; MO 92210-0-0008-B2]


Endangered and Threatened Wildlife and Plants; Petition To List 
Grand Canyon Cave Pseudoscorpion

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of 12-month petition finding.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 
12-month finding on a petition to list the Grand Canyon cave 
pseudoscorpion (Archeolarca cavicola) as threatened or endangered with 
critical habitat under the Endangered Species Act of 1973, as amended 
(Act). After review of the best scientific and commercial information 
available, we find that listing the Grand Canyon cave pseudoscorpion is 
not warranted at this time. However, we ask the public to submit to us 
any new information that becomes available concerning the threats to 
the Grand Canyon cave pseudoscorpion or its habitat at any time.

DATES: The finding announced in this document was made on July 19, 
2011.

ADDRESSES: This finding is available on the Internet at http://www.regulations.gov at Docket Number FWS-R2-ES-2011-0044. Supporting 
documentation we used in preparing this finding is available for public 
inspection, by appointment, during normal business hours by contacting 
the U.S. Fish and Wildlife Service, Arizona Ecological Services Field 
Office, 2321 W. Royal Palm Road, Suite 103, Phoenix, AZ 85021; 
telephone (602) 242-0210; facsimile (602) 242-2513. If you use a 
telecommunications device for the deaf (TDD), please call the Federal 
Information Relay Service (FIRS) at (800) 877-8339. Please submit any 
new information, comments, or questions concerning this finding to the 
above address.

FOR FURTHER INFORMATION CONTACT: Steve Spangle, Field Supervisor, U.S. 
Fish and Wildlife Service, Arizona Ecological Services Field Office, 
2321 W. Royal Palm Road, Suite 103, Phoenix, AZ 85021; telephone (602) 
242-0210; facsimile (602) 242-2513. If you use a telecommunications 
device for the deaf (TDD), please call the Federal Information Relay 
Service (FIRS) at (800) 877-8339.

SUPPLEMENTARY INFORMATION:

Background

    Section 4(b)(3)(B) of the Endangered Species Act of 1973, as 
amended (Act) (16 U.S.C. 1531 et seq.), requires that, for any petition 
containing substantial scientific or commercial information indicating 
that listing the species may be warranted, we make a finding within 12 
months of the date of receipt of the petition. In this finding we 
determine that the petitioned action is: (a) Not warranted, (b) 
warranted, or (c) warranted, but immediate proposal of a regulation 
implementing the petitioned action is precluded by other pending 
proposals to determine whether species are threatened or endangered, 
and expeditious progress is being made to add or remove qualified 
species from the Lists of Endangered and Threatened Wildlife and 
Plants. Section 4(b)(3)(C) of the Act requires that we treat a petition 
for which the requested action is found to be warranted but precluded 
as though resubmitted on the date of such finding, that is, requiring a 
subsequent finding to be made within 12 months. We must publish these 
12-month findings in the Federal Register.

Previous Federal Actions

    The Grand Canyon cave pseudoscorpion was formerly a candidate 2 
species, a taxon for which information in our possession indicated that 
proposing to list was possibly appropriate, but for which persuasive 
data on biological vulnerability and threats were not available to 
support a proposed listing rule (54 FR 554; January 6, 1989). The 
designation of candidate 2 species was discontinued in

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1996; therefore, the species has no candidate status.
    On June 25, 2007, we received a formal petition dated June 18, 
2007, from Forest Guardians (now WildEarth Guardians), requesting that 
we do the following: (1) Consider all full species in our Southwest 
Region ranked as G1 or G1G2 by the organization NatureServe for 
listing, except those that are currently listed, proposed for listing, 
or candidates; and (2) list each species under the Act as either 
endangered or threatened with critical habitat. The petitioners 
presented two tables that collectively listed 475 species for 
consideration and requested that the Service incorporate all analyses, 
references, and documentation provided by NatureServe in its online 
database http://www.natureserve.org/ into the petition. The petition 
clearly identified itself as a petition and included the appropriate 
identification information, as required in 50 CFR 424.14(a). We 
acknowledged the receipt of the petition in a letter to WildEarth 
Guardians dated July 11, 2007.
    On December 16, 2009, we made a 90-day finding that the petition 
presented substantial scientific information indicating that listing 67 
of the 475 species may be warranted; the Grand Canyon cave 
pseudoscorpion (incorrectly referenced as the Grand Canyon cave 
scorpion) was in that group of 67 species. Based on the evaluation of 
the information provided in the petition, we determined that the 
petition presented substantial information to indicate that listing the 
Grand Canyon cave pseudoscorpion may be warranted due to the present or 
threatened destruction, modification, or curtailment of its habitat or 
range resulting from groundwater pollution and recreational impacts, 
and to the inadequacy of existing regulatory mechanisms resulting from 
unregulated visitation. The 90-day finding and our initiation of a 
status review was published in the Federal Register on December 16, 
2009 (74 FR 66866). This notice constitutes the 12-month finding on the 
June 18, 2007, petition to list the Grand Canyon cave pseudoscorpion as 
threatened or endangered.

Species Information

Species Description

    In 1978 W. Calvin Welbourn collected one female specimen of the 
Grand Canyon cave pseudoscorpion (Class Arachnida, Order 
Pseudoscorpionida, Family Garypidae) in Grand Canyon National Park's 
Cave of the Domes. This specimen was first described by Muchmore (1981, 
p. 55). Welbourn's unpublished report (1978, p. 40) stated that the 
specimen was an undescribed troglophile. A troglophile is a species 
that can spend its entire life within caves, does not exhibit 
adaptations for living in caves, but can also be found in suitable 
habitats outside of caves, such as mines or animal burrows. This is in 
comparison to troglobites, which are species that are found exclusively 
in caves and have developed adaptations for cave life, such as 
heightened sense of hearing, touch, and smell. The Grand Canyon cave 
pseudoscorpion was recognized within the genus Archeolarca and was 
given the species name cavicola in recognition of its subterranean 
habitat where it was collected by Welbourn (1981, p. 55). The specimen 
collected in 1978 is the only one known to exist. No other individuals 
are known to have been collected since 1978, although very little 
effort has been made to collect this or other species in the genus 
(Service 1991, p. 3).
    Pseudoscorpions are tiny arachnids bearing large chelae, or claws, 
but lacking a telson, or stinger, that true scorpions possess. The 
specimen of Grand Canyon cave pseudoscorpion, when compared to other 
species of pseudoscorpions, such as Archeolarca welbourni and 
Archeolarca guadalupensis, was considered large (0.12 inches (in) or 
3.03 millimeters (mm)), had longer appendages, more reduced posterior 
eyes, and fewer setae (stiff bristles present on the body) on its upper 
dorsal section (Muchmore 1981, p. 56). Muchmore (1981, pp. 52-56) 
described three new species of Archeolarca, and concluded that the 
Grand Canyon cave pseudoscorpion showed the greatest overall adaption 
to the cave environment. Welbourn (1978, p. 40) noted that the specimen 
appeared to be similar to the pseudoscorpions from earth cracks in 
Wupatki National Mountain, Arizona, approximately 75 miles (121 
kilometers (km)) south of Grand Canyon National Park. Other species in 
the genus Archeolarca have been reported in California, Utah, Texas, 
and Oregon (Muchmore 1981, p. 56; Peck 1998, p. 23).

Distribution

    The Cave of the Domes in Grand Canyon National Park is currently 
the only known location for the Grand Canyon cave pseudoscorpion. 
Welbourn (1978, pp. 36-41) conducted a regional study of cave fauna on 
Horseshoe Mesa of the Grand Canyon from 1977 to 1978. Eight caves were 
examined including Babylon Cave, Crystal Forest Cave, Land's End Cave, 
Middle Cave, Scorpion Cave, Tse An Cho Cave, Tuning Fork Cave, and Cave 
of the Domes. All caves except Land's End Cave and Scorpion Cave were 
visited twice. On each visit, Welbourn (1978, p. 36) describes 
examining the walls, ceilings, and floors for animals and 
invertebrates. He identified 12 invertebrates from the 8 caves. The 
Grand Canyon cave pseudoscorpion was found only in the Cave of the 
Domes (Welbourn 1978, pp. 38-41).
    Wynne et al. (2008a, pp. 235-246) summarized all published and 
unpublished literature on cave-dwelling invertebrates within Grand 
Canyon National Park, as well as cave trip reports on file at Grand 
Canyon National Park Museum Collections. The literature review examined 
9 studies conducted between 1975 and 2001 representing surveys of 15 
caves in Grand Canyon National Park. Wynne et al. (2008a, pp. 237-238) 
reported 37 cave-dwelling invertebrates with the Grand Canyon cave 
pseudoscorpion referenced only in the Cave of the Domes. This species 
may possibly be endemic to Cave of the Domes. In fact, a study of 
patterns of endemism of eastern North American cave fauna reported that 
within the Pseudoscorpionida is a high level of single-cave endemism 
compared to other cave taxa (Christman et al. 2005, pp. 1444, 1447). 
However, cave biological research in Grand Canyon National Park is 
quite limited (Wynne 2010, pers. comm.; Drost 2010, pers. comm.) and 
more invertebrate surveys need to be conducted before we can conclude 
that the Grand Canyon cave pseudoscorpion is endemic to the Cave of the 
Domes. Further, because many cave-dwelling organisms are hard to find, 
cave inventories cannot be considered complete without intensive 
invertebrate trapping, baiting of the entity, and multiple site visits 
(Wynne 2010, pers. comm.). We cannot describe the distribution based on 
a single specimen; therefore, we are not able to determine the 
distribution of the Grand Canyon cave pseudoscorpion.

Habitat and Biology

    Most species of pseudoscorpions occur in tropical and subtropical 
areas throughout the world, although pseudoscorpions can also be found 
in temperate zones (Weygoldt 1969, pg. 108). They are found in a great 
variety of habitats, but one essential feature appears to be the 
presence of small crevices where they can retreat. All pseudoscorpion 
species spend most of their lives within these crevices and seldom 
appear on open ground. These small crevices can be found in rocks, tree 
bark, leaf litter, nests of birds and other small mammals, and 
buildings.

[[Page 42656]]

Another important habitat factor is humidity; most pseudoscorpions 
prefer high humidity, although some species are found in arid 
conditions, such as deserts (Weygoldt 1969, pp. 108-111).
    There are few studies on the ecology and habitat preferences of 
specific species of pseudoscorpions. We have no specific information 
about the habitat and biology of the Grand Canyon cave pseudoscorpion 
because the species is known from only one specimen. Accordingly, we 
can only speculate about their habitat requirements and biology based 
on the scant general information known about pseudoscorpions.
    Welbourn (1978, p. 37) observed that the single most important 
limiting factor for the cave fauna on Horseshoe Mesa, which includes 
Cave of the Domes, was the lack of moisture. Welbourn (1978, p. 37) 
reported that most of the caves surveyed were dry and dusty with low 
relative humidity, and that most of the caves examined, including Cave 
of the Domes, received moisture from rainfall that percolates through 
the limestone above. Welbourn (1978, p. 40) reported collecting the 
species ``in the Cross passage of Cave of the Domes in some organic 
material (grass).'' According to the Grand Canyon National Park's 
hydrologist, the Cave of the Domes is considered to be a dry cave with 
no discharge or pools, but that the Cave of the Domes has some small 
ephemeral drip zones (Rice 2010, pers. comm.). We do not know if the 
location where the Grand Canyon cave pseudoscorpion was found was 
optimal habitat or an accidental find, but if pseudoscorpions prefer 
humid locations, this location may not represent optimal habitat.
    Some species of pseudoscorpions are known to be phoretic (use 
another species for transportation) on other arthropods such as flies, 
beetles, and wasps. Pseudoscorpions will attach themselves (not as 
parasites) to the legs and appendages of the adult arthropod, which 
permits them to ``hitchhike.'' According to Poinar et al. (1998, p. 
79), the principal benefit of pseudoscorpion phoresy is dispersal; that 
is, to reach a new habitat with an adequate supply of food. We can only 
speculate on the presence of the one specimen of Grand Canyon cave 
pseudoscorpion in Cave of the Domes, but perhaps it was carried there 
and deposited by an arthropod.
    The Park Service's biological report (Hill et al. 1998, pg. 16) 
from Cave of the Domes indicated that packrat middens (nests) were 
observed inside Cave of the Domes. The report stated that a packrat 
midden was found ``in the second room of the cave''. Pseudoscorpions 
are often present in rodent nests (Francke and Villegas-Guzm[aacute]n 
2006, p. 289). Muchmore (1991, pers. comm.) stated that the genus 
Archeolarca does not usually inhabit caves but rather is found in 
packrat nests, although packrat middens are sometimes found in caves. 
Francke and Villegas-Guzm[aacute]n (2006, p. 297) conclude that 
pseudoscorpions most likely coexist with a particular rodent species in 
a mutualistic association (a relationship between two species where 
both species derive benefits) in which pseudoscorpions feed on adult 
and larval fleas, which reduces the parasite load within the host nest. 
The benefits to the pseudoscorpion include the host nest providing 
suitable microclimate, especially in semiarid regions, as well as food 
(i.e., mites, fleas, flies and their larvae). It is possible that this 
species may be associated with packrat middens or other small mammal 
nests within Cave of the Domes, but we cannot draw that conclusion 
based on one specimen.
    In summary, we lack sufficient information on the species to reach 
conclusions about the biology or the habitat needs of the Grand Canyon 
cave pseudoscorpion. This is primarily because we know of only one 
specimen, and we cannot make scientifically sound conclusions regarding 
habitat characteristics and biology based on a single specimen.

Factors Affecting the Grand Canyon Cave Pseudoscorpion

    Section 4 of the Act (16 U.S.C. 1533) and implementing regulations 
(50 CFR part 424) set forth procedures for adding species to, removing 
species from, or reclassifying species on the Federal Lists of 
Endangered and Threatened Wildlife and Plants. Under section 4(a)(1) of 
the Act, a species may be determined to be endangered or threatened 
based on any of the following five factors:
    (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range;
    (B) Overutilization for commercial, recreational, scientific, or 
educational purposes;
    (C) Disease or predation;
    (D) The inadequacy of existing regulatory mechanisms; or
    (E) Other natural or manmade factors affecting its continued 
existence.
    In making this finding, information pertaining to the Grand Canyon 
cave pseudoscorpion in relation to the five factors provided in section 
4(a)(1) of the Act is discussed below.

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

    The Arizona Game and Fish Department (2003, p. 2) stated that a 
threat to the Grand Canyon cave pseudoscorpion was groundwater 
pollution. Our previous discussion in the Habitat and Biology section 
indicates that Cave of the Domes, where the species was collected, is 
considered dry and has very little ephemeral water (i.e., small drip 
zones). Further, the specimen was found associated with dry, organic 
material (grass) in Cave of the Domes. This description of the site 
where the Grand Canyon cave pseudoscorpion was collected seems unlikely 
to be affected by groundwater pollution because it is relatively dry, 
and based on a single specimen we are unable to determine the type of 
cave habitat associated with this species. Additionally, we have no 
specific information regarding the presence or introduction of 
contaminants or pollutants in water sources on Horseshoe Mesa, which 
could percolate into the Cave of the Domes. Therefore, we are unable to 
determine if groundwater pollution is a threat.
    Cave of the Domes is the only cave in Grand Canyon National Park 
for which visitation is allowed. It is unknown whether recreation is 
modifying or destroying the Grand Canyon cave pseudoscorpion's habitat. 
A report from the Grand Canyon National Park (Western Speleological 
Institute 1954, pp. 1-2) stated that the cave has been badly vandalized 
and floor deposits have been marred by trampling. However, it is 
unknown if this damage affects the pseudoscorpion's habitat because 
that habitat is unknown. We note that vandalism and trampling have been 
identified as potential threats to other pseudoscorpion species, such 
as the Empire cave pseudoscorpion (Microcreagris imperialis) (Muchmore 
and Cokendolpher 1995, pp. 174-175) and the Tooth cave pseudoscorpion 
(Tartarocreagris texana) (Service 1994, pp. 62-63). If the Grand Canyon 
cave pseudoscorpion occupies packrat middens, as do other 
pseudoscorpions in the genus Archeolarca, then recreational foot 
traffic may be a discountable impact; however, we are lacking 
sufficient information on the habitat for this species. As such, we are 
unable to determine if recreational activity is affecting the Grand 
Canyon cave pseudoscorpion or its habitat.
    In summary, given the paucity of biological information regarding 
the Grand Canyon cave pseudoscorpion and its habitat, we cannot 
determine or

[[Page 42657]]

conclude that habitat degradation due to groundwater pollution or 
recreational activities in the Cave of the Domes is a threat to the 
species now or in the foreseeable future.

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

    Any commercial, recreational, scientific, or educational collection 
activities, including the collection of pseudoscorpions, would require 
a permit by the National Park Service. Because of this regulation, 
there is no data suggesting that overutilization for commercial, 
recreational, scientific, or educational purposes pose a threat to the 
species. There are no known commercial or recreational uses for Grand 
Canyon cave pseudoscorpions. Therefore, we find that the Grand Canyon 
cave pseudoscorpion is not threatened by overutilization now or in the 
foreseeable future.

Factor C. Disease or Predation

    We have no information to indicate that the Grand Canyon cave 
pseudoscorpion is subject to disease or predation. We have not 
encountered any information that indicates the contrary; however, in 
the absence of evidence that this factor may constitute a threat to the 
species, we cannot determine or conclude that the Grand Canyon cave 
pseudoscorpion is threatened by disease or predation now or in the 
foreseeable future.

Factor D. The Inadequacy of Existing Regulatory Mechanisms

    Under the current National Park Service policy, all caves in Grand 
Canyon National Park are closed to visitation by recreational users 
except for the Cave of the Domes. The Park Service has the authority, 
under the Federal Cave Resources Protection Act of 1988, to close areas 
to visitors if there is significant degradation of a resource or the 
threat of degradation or damage. On Park Service lands, all caves are 
deemed ``significant,'' and the Park Service protects the caves, 
including biological, cultural, and paleontological resources within 
the caves. The decision to regulate visitors or close the cave to 
recreational use is made by the Park Superintendent with supporting 
documentation from resource managers. Official criteria for determining 
recreational access to Grand Canyon National Park caves has not been 
established, but the initiation of a Cave Management Plan is planned.
    Cave of the Domes is located beneath Horseshoe Mesa and is well 
known to hikers and cavers. The Web site http://www.birdandhike.com 
provides a detailed overview of the cave, including photos and 
directions to the trailhead and to the mouth of the cave. The Web site 
http://www.kaibab.org also provides information about Cave of the Domes 
and states that many formations have been damaged by careless 
individuals and asks visitors to treat the cave with respect. As stated 
above, we lack data to assess the effect of recreation on the 
petitioned species. Therefore, due to the lack of information regarding 
impacts of recreational visitors and the Park Service's ability to 
close the area if additional information comes to light, we find that 
the Grand Canyon cave pseudoscorpion is not threatened by inadequacy of 
regulatory mechanisms now or in the foreseeable future.

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

    Model predictions are that temperatures in the Southwestern United 
States will continue to increase, with extreme weather events (such as 
heat waves, drought, and flooding) occurring with more frequency due to 
global climate change (Archer and Predick 2008, p. 24). It is unknown 
how cave-adapted taxa will respond to global climate change. Baseline 
information on ecosystem structure and community structure is lacking 
for many caves, and we do not know how cave-dwelling species will 
respond to rising temperatures. Different layers of a cave may be 
affected differently, depending on their depth. (Wynne et al. 2008b, p. 
241). There will most likely be a lag effect; caves with shallow 
vertical depth are predicted to have a more immediate response than 
caves with deeper vertical depth (Wynne 2010, pers. comm.). We have no 
information on the geophysical properties of Cave of the Domes. 
Researchers are currently attempting to understand the geophysical 
properties of caves as they relate to cave depth, the potential effects 
of rising surface temperatures on cave temperatures, and how the 
physiological requirements of cave-dwelling and cave-adapted species 
are affected by climate change (Drost 2010, pers. comm.). Based on the 
best available information, we cannot determine or conclude that 
climate change is a threat to the Grand Canyon cave pseudoscorpion now 
or in the foreseeable future.

Finding

    As required by the Act, we considered the five factors in assessing 
whether the Grand Canyon cave pseudoscorpion is threatened or 
endangered throughout all or a significant portion of its range. We 
examined the best scientific and commercial information available 
regarding the past, present, and future threats faced by the Grand 
Canyon cave pseudoscorpion. We reviewed the petition, information 
available in our files, other available published and unpublished 
information, and we consulted with recognized invertebrate experts and 
the Grand Canyon National Park biologist and hydrologist.
    In considering what factors might constitute threats, we must look 
beyond the mere exposure of the species to the factor to determine 
whether the species responds to the factor in a way that 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 a threat 
it 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 threatened or endangered 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 are operative threats that act on the species to the 
point that the species meets the definition of threatened or endangered 
under the Act.
    Based on our review of the best available scientific and commercial 
information pertaining to the five factors, we found no evidence to 
indicate that there are threats to the species or its habitat, from any 
of the five factors. For this reason, we conclude that the Grand Canyon 
cave pseudoscorpion does not meet the definition of a threatened or 
endangered species and are, therefore, recommending a finding of ``not 
warranted.''
    We request that you submit any new information concerning the 
distribution and status of, or threats to, the Grand Canyon cave 
pseudoscorpion to our U.S. Fish and Wildlife Service Office (see 
ADDRESSES) whenever it becomes available. New information will help us 
monitor the Grand Canyon cave pseudoscorpion and encourage its 
conservation. If an emergency situation develops for the Grand Canyon 
cave pseudoscorpion or any other species, we will act to provide 
immediate protection.

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References Cited

    A complete list of references cited is available on the Internet at 
http://www.regulations.gov and upon request from the U.S. Fish and 
Wildlife Service, Arizona Ecological Services Field Office (see 
ADDRESSES).

Author(s)

    The primary authors of this finding are the staff members of the 
Arizona Ecological Services Field Office.

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

    Dated: June 21, 2011.
Rowan W. Gould,
Acting Director, Fish and Wildlife Service.
[FR Doc. 2011-17864 Filed 7-18-11; 8:45 am]
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