[Federal Register: August 9, 2005 (Volume 70, Number 152)]
[Rules and Regulations]               
[Page 46303-46333]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[[Page 46303]]


Part III

Department of the Interior


Fish and Wildlife Service


50 CFR Part 17

Endangered and Threatened Wildlife and Plants; Listing Roswell 
springsnail, Koster's springsnail, Noel's amphipod, and Pecos assiminea 
as Endangered With Critical Habitat; Final Rule

[[Page 46304]]



Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AI15

Endangered and Threatened Wildlife and Plants; Listing Roswell 
springsnail, Koster's springsnail, Noel's amphipod, and Pecos assiminea 
as Endangered With Critical Habitat

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.


SUMMARY: We, the U.S. Fish and Wildlife Service (Service), list the 
Roswell springsnail (Pyrgulopsis roswellensis), Koster's springsnail 
(Juturnia kosteri), and Noel's amphipod (Gammarus desperatus) as 
endangered and the Pecos assiminea (Assiminea pecos) as endangered with 
critical habitat under the Endangered Species Act of 1973, as amended 
(Act). These four invertebrates occur at sinkholes, springs, and 
associated spring runs and wetland habitats. They are found at one site 
in Chaves County, New Mexico, and Pecos assiminea is also found at one 
site in Pecos County, Texas, and one site in Reeves County, Texas.
    These three snails and one amphipod have an exceedingly limited 
distribution, low mobility, and fragmented habitat. They are imperiled 
by introduced species, surface and groundwater contamination, oil and 
gas extraction activities within the supporting aquifer and watershed, 
local and regional groundwater depletion, severe drought, and direct 
loss of their habitat (e.g., through burning or removing marsh 
vegetation, or flooding of habitat). This final rule will implement the 
Federal protection and recovery provisions of the Act for these 
invertebrate species. We are also designating critical habitat for the 
Pecos assiminea in Texas.

DATES: This final rule is effective September 8, 2005.

ADDRESSES: Supporting documentation for this rulemaking is available 
for public inspection, by appointment, during normal business hours at 
the U.S. Fish and Wildlife Service, New Mexico Ecological Services 
Field Office, 2105 Osuna Road NE., Albuquerque, New Mexico 87113.

FOR FURTHER INFORMATION CONTACT: Susan MacMullin, Field Supervisor, New 
Mexico Ecological Services Field Office (telephone, 505-761-4706; 
facsimile, 505-346-2542).



    It is our intent to discuss only those topics directly relevant to 
this final listing determination. For more information on the four 
invertebrates, refer to the February 12, 2002, proposed rule (67 FR 
6459). However, some of this information is discussed in our analyses 
below, such as the summary of factors affecting the species.


    The Permian Basin of the southwestern United States contains one of 
the largest carbonate (limestone) deposits in the world (New Mexico 
Department of Game and Fish (NMDGF) 1998). Within the Permian Basin of 
the Southwestern United States lies the Roswell Basin. Located in 
southeastern New Mexico, this Basin has a surface area of around 31,080 
square kilometers (km) (12,000 square miles [mi]) and generally begins 
north of Roswell, New Mexico, and runs to the southeast of Carlsbad, 
New Mexico. The Roswell Basin contains a deep artesian aquifer and a 
shallow surficial aquifer. The action of water on soluble rocks (e.g., 
limestone and dolomite) has formed abundant ``karst'' features such as 
sinkholes, caverns, springs, and underground streams (White et al. 
1995). These hydrogeological formations create unique settings 
harboring diverse assemblages of flora and fauna. The isolated 
limestone and gypsum springs, seeps, and wetlands located in and around 
Roswell, New Mexico, and Pecos and Reeves Counties, Texas, provide the 
last known habitats in the world for several endemic species of fish, 
plants, mollusks, and crustaceans. These species include the Roswell 
springsnail and Koster's springsnail of the freshwater snail family 
Hydrobiidae, Pecos assiminea of the snail family Assimineidae, and 
Noel's amphipod (Gammaridae). These species are distributed in 
isolated, geographically separate populations, and likely evolved from 
parent species that once enjoyed a wide distribution during wetter, 
cooler climates of the Pleistocene. Such divergence has been well-
documented for aquatic and terrestrial macroinvertebrate groups within 
arid ecosystems of western North America (e.g., Taylor 1987; Metcalf 
and Smartt 1997; Bowman 1981; Cole 1985).
    North American snails of the family Hydrobiidae inhabit a great 
diversity of aquatic systems from surface to cave habitats, small 
springs to large rivers, and high energy riffles to slack water pools 
(Wu et al. 1997). Snails of the family Assimineidae are typically found 
in coastal brackish waters or along tropical and temperate seacoasts 
worldwide (Taylor 1987). Inland species of the genus Assiminea are 
known from around the world, and in North America they occur in 
California (Death Valley National Monument), Utah, New Mexico, Texas 
(Pecos and Reeves Counties), and Mexico (Bols[oacute]n de Cuatro 
    The Roswell springsnail and Koster's springsnail are aquatic 
species. These snails have lifespans of 9 to 15 months and reproduce 
several times during the spring through fall breeding season (Taylor 
1987; Pennak 1989; Brown 1991). Snails of the family Hydrobiidae are 
sexually dimorphic (there are characteristic differences between males 
and females), with females being characteristically larger and longer-
lived than males. As with other snails in the family, the Roswell 
springsnail and Koster's springsnail are completely aquatic but can 
survive in seepage areas, as long as flows are perennial and within the 
species' physiological tolerance limit. These two snails occupy spring 
heads and runs with variable water temperatures (10 to 20 [deg] Celsius 
[C] (50 to 68 [deg] Fahrenheit [F])) and slow-to-moderate water 
velocities over compact substrate ranging from deep organic silts to 
gypsum sands and gravel and compact substrate (NMDGF 1998). Conversely, 
the Pecos assiminea seldom occurs immersed in water, but prefers a 
humid microhabitat created by wet mud or beneath vegetation mats, 
typically within a few centimeters (cm) (inches (in)) of running water.
    Gastropods (snails) are a class of mollusks with a body divided 
into a foot and visceral mass and a head that usually bears eyes and 
tentacles. Like most gastropods, the Roswell springsnail, Koster's 
springsnail, and Pecos assiminea feed on algae, bacteria, and decaying 
organic material (NMDGF 1988). They will also incidentally ingest small 
invertebrates while grazing on algae and detritus (dead or partially 
decayed plant materials or animals).
    These snails are fairly small; Koster's springsnail is the largest 
of the three snails, and is about 4 to 4.5 millimeters (mm) (0.16 to 
0.18 in) long with a pale tan shell that is narrowly conical with up to 
4\1/4\ to 5\3/4\ whorls or twists. The Roswell springsnail is 3 to 3.5 
mm (0.12 to 0.14 in) long with a narrowly conical tan shell with up to 
5 whorls. Pecos assiminea is the smallest of the three, with a shell 
length of 1.55 to 1.87 mm (0.06 to 0.07 in) and a thin, nearly 
transparent chestnut-brown shell that is regularly conical with up to 
4\1/2\ strongly incised (shouldered) whorls and a broad oval opening. 
Although their shells are

[[Page 46305]]

similar, the Roswell springsnail is distinguished from Koster's 
springsnail by a dark, amber operculum (a lid which closes the shell 
opening when the animal is retracted) with white spiral streaks, while 
that of Koster's springsnail is nearly colorless. The genus Assiminea 
can be determined from other snail genera by an almost complete lack of 
tentacles, leaving the eyes within the tips of short eye stalks (Taylor 
    Taylor (1987) first described the Roswell springsnail from a 
``seepage'' along the west side of an impoundment in Area 7 at Bitter 
Lake National Wildlife Refuge (BLNWR, Refuge), Chaves County, New 
Mexico. Since then, Mehlhop (1992, 1993) has documented the species on 
the BLNWR and in March 1995 also found it in a spring on private land 
(i.e., North Spring) east of Roswell (NMDGF 1998). In 2004, the Roswell 
springsnail was determined to have been extirpated from this private 
land through habitat alteration (NMDGF 2005b). Monitoring efforts at 
BLNWR (1995 to 1998) led to the discovery of Roswell springsnail 
populations in Bitter Creek, the Sago Springs Complex, and a drainage 
canal along the west shoreline of Area 6. The Roswell springsnail is 
currently known only from BLNWR with the core population in the Sago 
Springs Complex and Bitter Creek. The Sago Springs complex is 
approximately 0.3 km long (1,000 linear feet), half of which is 
subterranean with flow in the upper reaches restricted to sinkholes. 
Bitter Creek is six times longer than the Sago Springs Complex and has 
a total length of 1.8 km (1.1 miles). Monthly monitoring and ecological 
studies of the Roswell springsnail initiated at BLNWR in June 1995 are 
ongoing (NMDGF 2005b, 2005c).
    Roswell springsnail formerly occurred in several other springs in 
the Roswell area, but these habitats have dried up apparently due to 
groundwater pumping and no longer contain the species (Cole 1981; 
Taylor 1983, 1987). As noted, the Roswell springsnail historically 
occurred on private land at North Spring, but could not be found during 
surveys in 2004 (NMDGF 2005b). Pleistocene fossils of the Roswell 
springsnail are known from Berrendo Creek and the Pecos River in Chaves 
County (Taylor 1987). No populations are currently known from these 
    Taylor (1987) first reported Koster's springsnail from Sago Spring 
at BLNWR. Another population was documented in 1995 at North Spring on 
private land east of Roswell and a second population was found at BLNWR 
on the west side of Area 3 during extensive surveys conducted between 
1998 and 2001 (Warrick 2005). The species formerly occurred in several 
other springs in the Roswell area, but these habitats have since dried 
up due to groundwater pumping and no longer contain the species (Cole 
1981; Taylor 1983, 1987; NMDGF 2005b). Pleistocene fossils of Koster's 
springsnail are known from North Spring River and South Spring Creek in 
Chaves County (Taylor 1987). Monthly monitoring and ecological studies 
of Koster's springsnail initiated at BLNWR in 1995 indicate the species 
is most abundant in the deep organic substrates of Bitter Creek (NMDGF 
1998, 2005b). It also occurs at the Sago Springs Complex, but in lower 
numbers. The species has not been found in recent times along the 
western boundary of Area 3 in BLNWR (NMDGF 2005b). Koster's springsnail 
has recently been extirpated at North Spring east of Roswell (NMDGF 
    Pecos assiminea is presently known from two sites at BLNWR, Chaves 
County, New Mexico, from a large population at Diamond Y Spring and its 
associated drainage (Diamond Y Springs Complex), Pecos County, Texas, 
and at East Sandia Spring, Reeves County, Texas. It was thought that 
Pecos assiminea occurred sporadically throughout the Bolson de Cuatro 

Cinegas, Coahuila, Mexico (Taylor 1987); however, recent investigations 
indicate that the population in Mexico might be a different species 
(Hershler 2005). Investigations are currently underway to determine 
whether the animals found in the vicinity of Coahuila, Mexico, are 
Pecos assiminea (Hershler 2005).
    Monitoring and ecological studies of Pecos assiminea initiated at 
BLNWR in 1995 showed the snail to be typically absent from substrate 
samples. Populations of Pecos assiminea occur sporadically along Bitter 
Creek, and a dense population was confirmed on moist vegetation and on 
muddy surfaces within 1 cm (0.39 in) of water in 1999 in an emergent 
marsh plant community around the perimeter of a sinkhole within the 
Sago Springs Complex (NMDGF 1999).

Noel's amphipod

    Noel's amphipod, in the family Gammaridae, is a small freshwater 
crustacean. Inland amphipods are sometimes referred to as freshwater 
shrimp. Noel's amphipod is brown-green in color with elongate, kidney-
shaped eyes, and flanked with red bands along the thoracic and 
abdominal segments, often with a red dorsal stripe. Males are slightly 
larger than females, and individuals range from 8.5 to 14.8 mm (0.33 to 
0.58 in) long (Cole 1981, 1985).
    Gammarids commonly inhabit shallow, cool, well-oxygenated waters of 
streams, ponds, ditches, sloughs, and springs (Holsinger 1976; Pennak 
1989). Because they are light-sensitive, these bottom-dwelling 
amphipods are active mostly at night and feed on algae, submergent 
vegetation, and decaying organic matter (Holsinger 1976; Pennak 1989). 
Young amphipods depend on microbial foods, such as algae and bacteria, 
associated with aquatic plants (Covich and Thorp 1991). Most amphipods 
complete their life cycle in one year and breed from February to 
October, depending on water temperature (Pennak 1978). Amphipods form 
breeding pairs that remain attached for 1 to 7 days at or near the 
substrate while continuing to feed and swim (Bousfield 1989). They can 
produce from 15 to 50 offspring, forming a ``brood.'' Most amphipods 
produce one brood but some species produce a series of broods during 
the breeding season (Pennak 1978).
    Noel's amphipod is one of three species of endemic amphipods of the 
Pecos River Basin occurring from Roswell, New Mexico, south to Fort 
Stockton, Texas, known collectively as the Gammarus-pecos complex (Cole 
1985). Noel's amphipod is currently known from the following sites at 
BLNWR: Sago Springs Complex, Bitter Creek, along the western boundary 
of Area 6, Area 7 spring-ditch, and Hunter Marsh. It is also found in a 
spring just outside the BLNWR boundary on private property owned by the 
City of Roswell (G. Warrick 2005). Noel's amphipod was first described 
by Cole (1981) from a 1967 collection of amphipods taken from North 
Spring, east of Roswell. Based on morphological similarities, specimens 
collected from Lander Springbrook near Roswell were also identified as 
Noel's amphipod (Cole 1981). The amphipod was extirpated from Lander 
Springbrook between 1951 and 1960, and the North Spring population was 
lost between 1978 and 1988. The extirpations were attributed to 
regional groundwater depletions and habitat alterations (spring 
channelization) respectively (Cole 1981, 1985).

Previous Federal Actions

    On November 22, 1985, we received a petition from Mr. Harold F. 
Olson, Director of the NMDGF, to add 11 species of New Mexican mollusks 
to the Federal list of endangered and threatened wildlife. Roswell 
springsnail (Pyrgulopsis roswellensis, formerly Fontelicella 
roswellensis (Hershler

[[Page 46306]]

1994)), Koster's springsnail (Juturnia kosteri, formerly Durangonella 
kosteri and Tryonia kosteri (Hershler et al. 2002)), and Pecos 
assiminea were among the 11 species. We determined that the petition 
presented substantial information that the requested action may be 
warranted and published a positive 90-day petition finding in the 
Federal Register on August 20, 1986 (51 FR 29671). A subsequent 12-
month finding published in the Federal Register on July 1, 1987 (52 FR 
24485), concluded that the petitioned action was warranted but 
precluded by other higher priority listing actions.
    On August 29, 2001, the Service announced a settlement agreement in 
response to litigation by the Center for Biological Diversity, the 
Southern Appalachian Biodiversity Project, and the California Native 
Plant Society. Terms of the agreement required that we submit to the 
Federal Register, on or by February 6, 2002, a 12-month finding and 
accompanying proposed listing rule and proposed critical habitat 
designation for the four invertebrates addressed in this final rule. 
This agreement was entered by the court on October 2, 2001 (Center for 
Biological Diversity, et al. v. Norton, Civ. No. 01-2063 (JR) 
(D.D.C.)). A proposed rule to list the four invertebrates as endangered 
with critical habitat was published in the Federal Register on February 
12, 2002 (67 FR 6459). On May 31, 2002, we reopened the public comment 
period for 90 days (67 FR 6459). In addition, we published newspaper 
notices inviting public comment and announcing the public hearing in 
the following newspapers in New Mexico: the Carlsbad Current-Argus, the 
Artesia Daily Press, the Roswell Daily Record, and the Albuquerque 
Journal. On June 18, 2002, we held a public hearing in Carlsbad, New 
Mexico, to solicit comments on the proposed rule.
    On May 4, 2005, we announced the availability of the draft economic 
analysis and draft environmental assessment for the proposal to 
designate critical habitat for the four invertebrates (70 FR 23083). 
Section 4(b)(2) of the Act requires that we consider economic impacts, 
impacts to national security, and other relevant impacts prior to 
making a final decision on what areas to designate as critical habitat. 
We solicited data and comments from the public on these draft 
documents, as well as on all aspects of our proposal, so that we could 
consider these in this final determination.

Summary of Comments and Recommendations

    In the notices announcing the public comment periods, we requested 
that all interested parties submit comments on the proposed listings 
and critical habitat designation, as well as on the associated draft 
economic analysis and draft environmental assessment, and we also 
requested information pertaining to any actions that affect the four 
invertebrates; their current status, ecology, distribution, and 
threats; and management or conservation efforts in place. We requested 
this information in order to make a final listing determination based 
on the best scientific and commercial data currently available. We also 
solicited four independent experts who are familiar with these species 
to peer review the proposed listing and critical habitat designation. 
Two of the peer reviewers submitted substantial comments, but did not 
support or oppose the proposal. During the public comment periods, we 
also received 967 written comments (952 written comments were 
identical, in the form of automatically generated emails), and 7 
speakers gave verbal comments at the public hearing. Of those oral 
comments, one supported the proposal, two were opposed to the proposal, 
and four provided additional information. Of the written comments, 956 
supported the proposal, 8 were opposed, and 3 were neutral but provided 
information. All substantive information provided during the public 
comment periods, written and verbal, either has been incorporated 
directly into this final determination or is addressed below. Similar 
comments are grouped together by issue.

Issue 1: Biological Concerns

    (1) Comment: It is unlikely that Melanoides tuberculata, a fully 
aquatic animal, competes with Pecos assiminea, a semi-terrestrial 
species. On the other hand, the presence of introduced Melanoides 
tuberculata could pose a serious threat to aquatic species such as 
Koster's springsnail, Roswell springsnail, or Noel's amphipod.
    Our Response: The commenter is correct. It is unlikely that 
Melanoides would be a competitor with Pecos assiminea and it is very 
likely that it may be a serious threat to Koster's springsnail, Roswell 
springsnail, and Noel's amphipod. We have a more complete discussion of 
the threat of introduced species under the section, ``Summary of 
Factors Affecting the Species'' below.
    (2) Comment: The NMDGF concluded in 1999 that all four invertebrate 
species are stable on the BLNWR. There is no evidence that these 
species are at risk.
    Our Response: All four invertebrates are classified as Endangered 
by the NMDGF under the Wildlife Conservation Act of 1974 (i.e., State 
Endangered Species Act) (19 NMAC 33.6.8). As such, the NMDGF supports 
the listing and critical habitat designation for these species. They 
report that recent (1992 to present) population and habitat monitoring 
on BLNWR has documented the persistence of these species; however, they 
still face significant threats (Lang 2002, NMDGF 2005a). Our current 
understanding of the threats to the four invertebrates and their 
habitat are fully described under the ``Summary of Factors Affecting 
the Species'' section below.
    (3) Comment: Oil and gas development activities in the vicinity of 
BLNWR pose no threat to the four invertebrates because the New Mexico 
Oil Conservation Division regulations for installation of oil and gas 
wells provide protections to limit impacts.
    Our Response: The New Mexico Interstate Stream Commission (NMISC) 
and NMDGF submitted information that is consistent with the proposed 
rule, which indicated oil and gas, residential, or industrial 
development on the private lands immediately west of BLNWR may 
constitute a threat to spring water quality (Balleau et al. 1999; 
McCord et al. 2005; NMDGF 2005a) (see ``Summary of Factors Affecting 
the Species'' section below). The NMDGF also presented an overview of 
oil and gas production and potential risk to the four invertebrates 
(NMDGF 2005a). They note that, although there are no known cases of 
groundwater contamination by leaking oil or gas wells in the source-
water capture zone for the Middle Area of BLNWR (discussed further 
under ``Water Quality'' section below), groundwater contamination from 
petroleum products has been documented north of Roswell (NMDGF 2005a).
    There is a history of oil and gas industry operations on and 
adjacent to BLNWR, which have resulted in the spillage of oil and brine 
onto the BLNWR. For example, annual reports from 1994 to 1998 document 
four oil and gas related accidents on and immediately adjacent to BLNWR 
(NMDGF 2002; NMISC 2002). In May 1993, a private corporation began 
drilling a well on adjacent Bureau of Land Management (BLM) lands when 
they hit a water flow with a high chloride content (6,000 parts per 
million). The salt water was eventually contained, but serves as an 
example of

[[Page 46307]]

potential issues from oil and gas development (Service 2002). 
Additionally, in 1996, about 70 to 80 barrels of oil spilled within a 
berm on an adjacent oil well located on BLM lands (Service 2002). In 
1997, an additional 11 barrels of crude oil leaked into the BLNWR 
boundary (Service 2002). In 1998, BLNWR personnel documented probable 
violations of New Mexico Oil Conservation Division regulations (e.g., a 
substandard pit for drilling cuttings, fire hazards, lack of spillage 
notification) (Service 2002; NMISC 2002). In 2000, there was an 
additional oil spill on adjacent BLM lands (NMISC 2002).
    Development of another 91 natural gas and oil wells has been 
anticipated on lands managed by the BLM within the source-water capture 
zone (NMDGF 2005a). Contamination of groundwater from underground leaks 
has the potential to occur in the future, but existing drilling and 
casing regulations by the State of New Mexico's Oil Conservation 
Division and requirements of the BLM for oil and gas drilling and 
operation in cave and karst areas (BLM 1997) are likely to 
substantially reduce this probability. The NMDGF indicates that a more 
likely pathway for petroleum-product contamination of groundwater is 
from leaking storage and transport facilities from the well site 
downstream to processing facilities (NMDGF 2005a). These may include 
leaking pipelines, overflowing storage tanks, leaking valves, and other 
sources. These data indicate that oil and gas production and 
distribution continue to threaten the four invertebrates.
    (4) Comment: Contamination threats to the four invertebrates are 
not limited to oil and gas development, but also include fire effects. 
Immediate and short-term adverse effects have been demonstrated from 
the March 2000 Sandhill Fire (NMISC 2002).
    Our Response: NMDGF recently reviewed the effects of fire on the 
invertebrates (NMDGF 2005a). We agree with their assessment and 
summarize much of the information below. We recognize that populations 
of these four invertebrates have the potential to be eliminated or 
habitat may be rendered unsuitable if fire results in complete 
combustion of vegetation and litter, high soil temperatures, 
significant amounts of ash flow, large changes in water chemistry 
(e.g., dissolved oxygen), or extensive vegetation removal resulting in 
soil and litter drying. As such, we have also revised the ``Summary of 
Factors Affecting the Species'' section below to include a more 
detailed analysis on the threat of wildfire.
    (5) Comment: Much of the literature is overly general in nature and 
is not site-or species-specific. Including such citations leaves 
readers to conclude that a particular author made a statement or 
presented data that specifically applies to the threats you believe 
exist for these invertebrates.
    Our Response: In determining and evaluating threats to the four 
invertebrates, we used the best scientific and commercial data 
available. This included articles published in peer-reviewed journals, 
data collected by NMDGF, and comments received on the proposed rule, 
draft economic analysis, and environmental assessment. You are correct 
that some of our citations are not specific to these species or the 
geographic area. Nevertheless, the citations offer evidence that 
certain threats are real for the species because similar examples have 
been documented elsewhere.
    (6) Comment: The allegation that fire caused significant decreases 
in invertebrate populations implies that quantitative sampling was 
conducted. The Service and NMDGF rarely conduct quantitative sampling, 
and the case may be overstated in your proposal.
    Our Response: Extensive quantitative pre- and post-fire monitoring 
was conducted by the NMDGF (NMDGF 2005c). Immediately following the 
Sandhill fire, Lang (2001) documented a decrease in species richness of 
localized populations of aquatic macroinvertebrates. For example, in 
1996 densities of Noel's amphipod at Dragonfly Spring were estimated at 
11,625 per square meter (m\2\). Out of 74 post-fire monitoring 
collections conducted from March 2000 to August 2004, only four Noel's 
amphipod were found (NMDGF 2005c).
    (7) Comment: Does non-native vegetation such as saltcedar (Tamarix 
sp.) threaten the invertebrates? Will New Mexico's ability to eradicate 
or manage saltcedar be restricted if these species are listed?
    Our Response: Saltcedar management or eradication activities would 
be subject to section 7 consultation requirements if a proposed project 
has the potential to affect the four invertebrate species or designated 
critical habitat. However, the environmental assessment found that some 
activities may be considered to be of benefit to the four invertebrate 
species (Service 2005). Examples of such beneficial actions could 
include removal and control of non-native vegetation, restoration of 
wetlands, and removal of non-native species.
    Non-native saltcedar is present on BLNWR and The Nature Conservancy 
(TNC) lands at the Diamond Y Spring and East Sandia Springs preserves 
(Service 2005). This non-native species is currently being controlled 
where possible by BLNWR and TNC staff. Control and removal of non-
native vegetation was identified as a factor responsible for 
extirpation of localized populations of Pecos assiminea in Mexico and 
New Mexico (Taylor 1987). However, it is possible that removal and 
control of saltcedar will improve habitat and hydrologic conditions at 
springs and seeps (Service 2005). See also ``Factor C'' under the 
``Summary of Factors Affecting the Species'' section below.
    (8) Comment: Have laboratory toxicity tests been conducted to 
determine the four invertebrates' sensitivity to low oxygen, sediments, 
or contaminants?
    Our Response: To our knowledge, laboratory tests have not been 
conducted specifically on these species to determine their sensitivity 
to low oxygen, sediments, or contaminants.
    (9) Comment: Equating the springsnails with Higgin's eye mussel is 
inappropriate. Clearly, clams and mussels are very different creatures 
than springsnails.
    Our Response: The commenter is correct that mussels that live in 
the substrate and filter water to obtain nutrition are very different 
from springsnails that crawl on the substrate and scrape periphyton 
(various forms of algae and diatoms) off the substrate. Unfortunately, 
very little research has been done specifically on the effects of 
contaminants on springsnails and mussels are one of the most closely 
related groups available for comparison. However, this reference has 
been removed from this final rule.
    (10) Comment: The relevance of South Spring River is not apparent 
in your discussion of Noel's amphipod. The South Spring River has been 
dry for many years.
    Our Response: The discussion of Noel's amphipod and the dry South 
Spring River was included to document that this previously known 
population has likely been extirpated.
    (11) Comment: Are crayfish known predators of springsnails?
    Our Response: Crayfish are known to consume aquatic macrophytes and 
algae that springsnails rely on for grazing and egg laying (Service 
2004b). In addition, crayfish have been cited as a threat and are known 
to directly prey upon aquatic invertebrates such as springsnails (e.g., 
Three Forks springsnail (Pyrgulopsis trivialis)) (Arizona Game and Fish 
Department 2003; Service 2004b). Nevertheless, we have not observed any 
crayfish within habitat occupied by

[[Page 46308]]

these four invertebrates, with the exception of Diamond Y Springs 
Complex where an undescribed native crayfish occurs. See also ``Factor 
C'' under the ``Summary of Factors Affecting the Species'' section 
    (12) Comment: Effects to these species from prolonged drought, 
nutrient enrichment, and sedimentation are all unsubstantiated.
    Our Response: There is no doubt that prolonged drought leading to 
spring diminishment or drying would have a negative impact on the 
invertebrates. Little research has been done specifically on 
springsnails to document their response to elevated nutrients, 
contaminants, or sedimentation. However, based on biological principles 
and effects observed in other related invertebrates, we can draw 
reasonable conclusions about what we would expect to happen to these 
    (13) Comment: Have surveys for these species been conducted at 
Bottomless Lakes State Park?
    Our Response: Surveys were conducted on Bottomless Lakes State Park 
during the 1990s by the NMDGF and during the 1980s by D.W. Taylor. 
Perennial sinks west-northwest of Lea Lake and its outflow to the 
south, which eventually flows to the BLM Overflow Wetlands, were also 
surveyed for these invertebrates (Lang 2005). Although potentially 
suitable habitat for the four invertebrates is available at Bottomless 
Lakes State Park, these surveys failed to document their occurrence 
(New Mexico Energy Minerals and Natural Resources Department 2000; 
NMDGF 2005b).
    (14) Comment: A new population of Noel's amphipod has been recently 
discovered on BLNWR.
    Our Response: The commenter is correct. Noel's amphipod currently 
persists on BLNWR at the Sago Spring wetland complex (including 
Sinkhole No. 31), Bitter Creek, and along the western boundary of Area 
6, in the west ditch along Area 7, and along the northwest fenceline of 
Hunter Marsh (NMDGF 2005c). A new population was discovered in 2004 in 
a spring belonging to the City of Roswell that borders BLNWR. This 
population is included in the listing portion of this final rule, but 
is not within the designation of critical habitat. The critical habitat 
designation does not include these private lands because section 
4(b)(4) of the Act and the Administrative Procedure Act (5 U.S.C. 551 
et seq.) requires that areas designated as critical habitat must first 
be proposed as such. Thus, we cannot make additions in this final rule 
to include areas that were not included in the proposed rule. 
Designation of such areas would require a new or revised proposal and 
subsequent final rule. Should critical habitat be considered in the 
future for the Noel's amphipod, we will consider this area in any such 
    (15) Comment: The ongoing drought appears to be more of a threat to 
these species than groundwater pumping.
    Our Response: We agree. Please refer to the ``Summary of Factors 
Affecting the Species'' for further discussion of this issue.
    (16) Comment: The proposed rule lacks documentation of groundwater 
or surface contamination threats to the four invertebrates.
    Our Response: Based upon public comments and information received, 
we have updated our analysis to include our current understanding of 
the threats from groundwater or surface contamination to the four 
invertebrates. Please see the ``Summary of Factors Affecting the 
Species'' section.
    (17) Comment: The Pleistocene Era was mentioned several times in 
the proposed rule. Does the Service intend to recover these species to 
levels that were present during this historic era?
    Our Response: No, section 4 of the Act and its implementing 
regulations (50 CFR part 424) set forth the procedures for adding 
species to the List of Endangered and Threatened Wildlife and Plants. A 
species may be determined to be endangered or threatened due to one or 
more of the five factors described in section 4(a)(1) of the Act. As 
detailed below in our analysis, we examine the listing factors and 
their application to the four invertebrates. The discussion of these 
species in relation to the Pleistocene Era was presented as evidence of 
an apparent historical decline in the numbers, range, and distribution. 
We did not intend to suggest that the four invertebrates need to be 
restored to Pleistocene Era levels to be considered recovered.
    (18) Comment: Is there a plan to control introduced or exotic 
snails or other species that may prey upon or compete with the four 
    Our Response: BLNWR is managed for wildlife conservation, which 
includes restoration and maintenance of biological integrity, 
diversity, and environmental health. Major land management activities 
on BLNWR include water level management in impoundments to provide 
habitat for waterfowl, shorebirds, and other groups of species, habitat 
restoration, prescribed burning, control of saltcedar, and management 
of noxious weeds (Service 2005a). Management or removal of exotic 
species that compete with these invertebrates will be evaluated in the 
development of a recovery plan, but this management is currently 
conducted as appropriate. For example, removal of non-native fishes 
from Diamond Y Springs Complex using antimycin, netting, and trapping 
was conducted in the past for conservation of Leon Springs pupfish 
(Service 2005a). For further information and analysis concerning exotic 
species, please refer to the ``Factor C'' under the ``Summary of 
Factors Affecting the Species'' section.

Issue 2: Procedural and Legal Compliance

    (19) Comment: In the proposed rule for the four invertebrate 
species, restrictions are proposed on groundwater pumping within the 
Pecos Basin, which would have serious effects on the water supply and 
use of water by the citizens of New Mexico.
    Our Response: We disagree, the proposed rule did not propose 
restrictions on groundwater pumping. Consistent with our Interagency 
Cooperative Policy for Endangered Species Act Section 9 Prohibitions, 
published in the Federal Register on July 1, 1994 (59 FR 34272), we 
identified in the proposed rule those activities that we believe would 
or would not constitute a violation of the prohibitions identified in 
section 9 of the Act. The final Federal listing of these four 
invertebrates under the Act requires that Federal agencies consult with 
the Service on activities involving Federal funding, a Federal permit, 
Federal authorization,or other Federal actions. Consultation (under 
section 7 of the Act) is required when activities have the potential to 
affect the four invertebrates or designated critical habitat. The 
consultation will analyze and determine to what degree the species are 
impacted by the proposed action. Section 7 of the Act prohibits actions 
funded, authorized, or carried out by Federal agencies from 
jeopardizing the continued existence of a listed species or destroying 
or adversely modifying the listed species' critical habitat. This final 
Federal listing does not restrict groundwater pumping or any other 
    The environmental assessment found that spring flows within the 
proposed critical habitat on BLNWR are already protected by existing 
water rights afforded by the New Mexico Office of the State Engineer's 
administration of the Roswell Basin. In 1967, water rights were 
adjudicated in the Roswell Basin, wells were metered, and pumping rates 
administered by the Office of the State Engineer (OSE). Currently, any

[[Page 46309]]

proposed change in use of water (underground or surface depletion) in 
the Roswell Basin will undergo analysis by OSE to determine if there 
would be impairment to existing water rights (McCord et al. 2005). The 
OSE will not allow such change if it impairs the Federal water right in 
any respect (NMISC 2005). Thus the spring flows on BLNWR should be 
protected from any changes in groundwater pumping near the refuge in 
the future.
    In Texas, Pecos assiminea currently has no State or other 
regulatory protection. Some protection for the habitat of this species 
is provided with the ownership of the springs by TNC (Karges 2003). 
Groundwater pumping that could affect spring flows is subject to 
limited regulation in Texas. State agencies do not control groundwater 
pumping, and Texas courts have held that, with few exceptions, 
landowners have the right to take all the water that can be captured 
under their land (rule of capture), regardless of impacts to neighbors 
or natural resources. As noted in the economic analysis, within Texas 
further hydrological studies are necessary to determine the impact of 
groundwater pumping on surface and groundwater levels at Units 3 and 4. 
The TNC has stated that additional research on the delineation of 
watersheds is crucial to the sustainable, long-term conservation of the 
springs. If hydrological studies determine a link between the various 
aquifers, we would work with private landowners on a volunteer basis to 
minimize impacts to the Pecos assiminea from groundwater withdrawals.
    (20) Comment: The groundwater depletion analysis fails to rely upon 
the best available science, does not utilize an accurate and reliable 
model, and mischaracterizes effects of groundwater pumping.
    Our Response: Based upon new information we received during the 
comment periods, we revised our analysis from the proposed rule to 
reflect our current understanding regarding the threat of groundwater 
depletion on the four invertebrates and their habitat in New Mexico. 
Please refer to the ``Summary of Factors Affecting Species'' section.
    (21) Comment: The status of these species will not improve if they 
are listed.
    Our Response: Federal listing in and of itself does not improve the 
status of the species. Listing these species authorizes the development 
of a recovery plan. The recovery plan will likely identify both State 
and Federal efforts for conservation of these species and establish a 
framework for agencies and stakeholders to coordinate activities and 
cooperate with each other in conservation efforts. The plan will set 
recovery priorities and describe site-specific management actions 
necessary to achieve conservation and survival of the four 
invertebrates. See also response to comment 22 below for related 
information about the five factors described in section 4(a)(1) of the 
Act. Also note the discussion on section 7 consultation requirements in 
our response to comment 19 above.
    (22) Comment: Why does the Service want to list these four 
invertebrates when they are already within protected areas?
    Our Response: We have analyzed the threats to these species based 
upon the five factors described in section 4(a)(1) of the Act. Although 
these species occur on areas that are currently managed for 
conservation purposes, we have determined based on our analysis of the 
threats discussed below in the section ``Summary of Factors Affecting 
the Species,'' that these four invertebrate species are in danger of 
extinction throughout all or a significant portion of their respective 
ranges. Our analysis determined that these species are threatened by 
activities such as oil and gas production and development, groundwater 
pumping, and introduction of non-native species that are beyond the 
boundaries and/or the management protected areas where the species are 
found. Thus, the four invertebrates meet the definition of endangered 
    (23) Comment: If these species are listed, is there a possible 
effect to the U.S. Bureau of Reclamation with respect to delivery of 
irrigation water?
    Our Response: Federal listing will require the Bureau of 
Reclamation (Reclamation) to consult with us on activities that have 
the potential to adversely affect the four invertebrates or designated 
critical habitat. None of Reclamation's current projects will be 
affected by the listing of the invertebrates and we are not aware of 
any future projects that may be affected by the listing. Delivery of 
irrigation water occurs via the Pecos River and we do not anticipate 
that listing these species will affect that activity.
    (24) Comment: Will the listing of these species impede the ability 
of the State of New Mexico to meet Pecos Compact River obligations?
    Our Response: No, the NMISC has been actively acquiring and leasing 
water rights to meet the State's delivery obligations to Texas as 
specified in the Pecos River Compact and pursuant to an Amended Decree 
entered by the U.S. Supreme Court. For example, between 1991 and 1999, 
$27.8 million was spent on the Pecos River water rights acquisition 
program. We do not anticipate that the listing of these species or the 
designation of critical habitat will alter the ability of the NMISC to 
meet Pecos River Compact delivery obligations. The amount of water 
being pumped from the Roswell Basin should not change; however, the use 
of water will change. For example, instead of being applied to fields, 
the water may be delivered to the Pecos River directly to meet Compact 
delivery obligations.
    (25) Comment: Will oil and gas exploration be further restricted in 
areas designated as critical habitat?
    Our Response: No, the Service does not anticipate that the 
designation of critical habitat will restrict oil and gas exploration. 
Section 7 consultation, when required, would analyze any impacts to the 
species and their designated critical habitat. The environmental 
assessment found that oil and gas projects with Federal involvement in 
the BLNWR and the surrounding area are already subject to stipulations 
for protecting groundwater (Service 2005). The Oil Conservation 
Division of the New Mexico Energy, Minerals, and Natural Resources 
Department regulates oil and gas well drilling and casing in part to 
prevent contamination of groundwater (19 NMAC 15.3).
    BLNWR is excluded from the designation of critical habitat for the 
four invertebrate species, and critical habitat would not result in 
additional section 7 consultations on federally supported oil and gas 
projects. Oil and gas well development in the vicinity of Diamond Y 
Springs Complex and East Sandia Spring occurs on private lands with no 
Federal involvement. Therefore, section 7 consultations on the effects 
to designated critical habitat would likely not occur for these 
projects. For this reason, we do not believe there would be any 
additional restrictions to oil and gas exploration activities.

Issue 3: National Environmental Policy Act (NEPA) Compliance and 
Economic Analysis

    (26) Comment: What has regulation or policy of Federal actions cost 
State and County governments before listing and critical habitat 
    Our Response: Since the proposed listing of the four invertebrates 
species, there have been specific conservation actions implemented that 
have taken into account the protection of the species. An estimated 
$366,000 to $494,000 in costs have been incurred by Federal and State 
agencies for the four invertebrates (Service 2005b). These

[[Page 46310]]

costs are related to developing the New Mexico State recovery plan and 
have included monitoring the four invertebrates' habitat, consultant 
fees, staff time devoted to developing the plan, administrative costs 
related to past conferences under section 7 of the Act, and associated 
monitoring of invertebrate habitat. We did not find that County 
governments have incurred any costs related to the conservation of 
these species.
    (27) Comment: Does the Service have an estimate of the costs 
required to recover the four invertebrates?
    Our Response: The costs of actions to recover the four 
invertebrates will be estimated during the development of a recovery 
    (28) Comment: The economic analysis should consider benefits of the 
critical habitat designation.
    Our Response: In the context of a critical habitat designation, the 
primary purpose of the rulemaking (i.e., the direct benefit) is to 
designate areas that have the features on which the species depend and 
that are in need of special management.
    The designation of critical habitat may result in two distinct 
categories of benefits to society: (1) Use benefits; and (2) non-use 
benefits. Use benefits are simply the social benefits that accrue from 
the physical use of a resource. Visiting critical habitat to see 
endangered species in their natural habitat would be a primary example. 
Non-use benefits, in contrast, represent welfare gains from ``just 
knowing'' that a particular listed species'' natural habitat is being 
specially managed for the survival and recovery of that species. Both 
use and non-use benefits may occur unaccompanied by any market 
    A primary reason for conducting an economic analysis is to provide 
information regarding the economic impacts associated with a proposed 
critical habitat designation. Section 4(b)(2) of the Act requires the 
Secretary to designate critical habitat based on the best scientific 
data available after taking into consideration the economic impact, 
impact to national security, and any other relevant impact, of 
specifying any particular area as critical habitat. Economic impacts 
can be both positive and negative and by definition, are observable 
through market transactions.
    Where data are available, the economic analysis attempts to 
recognize and measure the net economic impact of the proposed 
designation. For example, if the fencing of a species' habitat to 
restrict motor vehicles results in an increase in the number of 
individuals visiting the site for wildlife viewing, then the analysis 
would recognize the potential for a positive economic impact and 
attempt to quantify the effect (e.g., impacts that would be associated 
with an increase in tourism spending by wildlife viewers). In this 
particular instance, however, the economic analysis did not identify 
estimates or measures of positive economic impacts that could offset 
some of the negative economic impacts analyzed earlier in this 
    While the Act requires the Service to specifically consider the 
economic impact of a designation, it does not require the Service to 
explicitly consider any broader social benefits (or costs) that may be 
associated with the designation. In fact, the Service believes that 
this is by Congressional design, because the Act explicitly states that 
it is the Federal government's policy to conserve all threatened and 
endangered species and the ecosystems upon which they depend. While 
section 4(b)(2) of the Act gives the Secretary discretion to exclude 
certain areas from the final designation, she is authorized to do so 
only if an exclusion does not result in the extinction of the species. 
Thus, the Service believes that explicit consideration of broader 
social values for the species and its habitat, beyond economic impacts, 
is not necessary as Congress has already clarified the importance our 
society places on conserving all threatened and endangered species and 
their natural habitats upon which they depend. In terms of carrying out 
its responsibilities under section 4(b)(2) then, the Service need only 
consider whether the economic impacts (both positive and negative) are 
significant enough to merit exclusion of any particular area without 
causing the species to go extinct.
    (29) Comment: The economic analysis overstates costs by including 
past costs that occurred before the species was listed, costs that 
would result from the listing alone, and costs that derive from 
conservation efforts for other listed species. Similarly, the economic 
analysis includes costs of consultation with the Environmental 
Protection Agency (EPA) regarding Concentrated Animal Feeding 
Operations (CAFOs), which should be primarily associated with other 
listed species, and the listing of the four invertebrates, and not 
critical habitat designation.
    Our Response: This analysis identifies those economic activities 
believed to most likely threaten the four invertebrates and their 
habitat and, where possible, quantifies the economic impact to avoid, 
mitigate, or compensate for such threats within the boundaries of the 
critical habitat determination. The economic analysis considers past 
impacts associated with species conservation efforts that have been 
incurred since the proposed listing and critical habitat determination 
in 2002. The impact of these efforts is considered relevant to 
understanding the potential impact of the listing and critical habitat 
determination. Further, due to the difficulty in making a distinction 
between listing and critical habitat effects within critical habitat 
boundaries, this analysis considers all future conservation-related 
impacts to be coextensive with the designation.
    The consideration of co-extensive costs was mandated by the 10th 
Circuit Court of Appeals ruling in the New Mexico Cattle Growers 
Association case (248 F.3d at 1285), which directed us to consider all 
impacts, ``regardless of whether those impacts are attributable co-
extensively to other causes.'' As explained in the economic analysis, 
due to possible overlapping regulatory schemes and other reasons, there 
are also some elements of the analysis which may overstate some costs.
    Conversely, the 9th Circuit has recently ruled (``Gifford 
Pinchot,'' 378 F.3d at 1071) that the Service's regulations defining 
``adverse modification'' of critical habitat are invalid because they 
define adverse modification as affecting both survival and recovery of 
a species. The Court directed us to consider that adverse modification 
should be focused on impacts to recovery. While we have not yet 
proposed a new definition for public review and comment, changing the 
adverse modification definition to respond to the Court's direction may 
result in additional costs associated with critical habitat definitions 
(depending upon the outcome of the rulemaking).
    As described in section 1.2 of the economic analysis, coextensive 
effects may also include impacts associated with overlapping protective 
measures of other Federal, State, and local laws that aid habitat 
conservation in the areas proposed for designation, including 
protections for other listed species. These measures may be in part 
precipitated by the consideration of the presence of the species and 
impending critical habitat determination. Because the quantified 
habitat conservation efforts, regardless of their primary impetus, 
afford protection to the four invertebrates, they likely contribute to 
the efficacy of the critical habitat determination efforts. The impacts 
of these actions are therefore considered relevant for understanding 
the full effect of the proposed critical habitat determination. 
Enforcement actions

[[Page 46311]]

taken in response to violations of the Act, however, are not included.
    (30) Comment: The economic analysis inappropriately includes costs 
of delays in proposed drilling operations associated with industry 
appeals on applications for drilling permits. The oil and gas industry, 
however, is appealing environmental protections associated with their 
permits and burdening themselves. This should not be included as a cost 
of the critical habitat designation.
    Our Response: Industry appeals regarding drilling applications are 
a result of the implementation of environmental regulations, including 
the Act, that recommend additional species and habitat conservation 
efforts be undertaken with the drilling activity. The economic impacts 
of these delays are therefore considered relevant in understanding the 
impact of conservation efforts for the four invertebrates.
    (31) Comment: It is unclear from the economic analysis what 
additional protections from oil and gas activities may be provided by 
the Service for the four invertebrates as the economic analysis 
includes costs associated with the listing and with protections for 
other species, but no additional costs associated specifically with the 
critical habitat designation.
    Our Response: This analysis identifies the types of modifications 
to economic activities that may be undertaken to avoid, mitigate, or 
compensate for threats to the species and habitat. The draft economic 
analysis acknowledges the difficulty in distinguishing between listing 
and critical habitat effects and therefore considers all future 
conservation-related impacts to be coextensive with the critical 
habitat designation. Further, the relative level to which multiple 
considerations, including that of other species, contribute to the 
undertaking of a conservation effort is unclear. The impacts quantified 
in the analysis are assumed to be in some part precipitated by the 
critical habitat designation for the four invertebrates. Absent 
information on the specific increment by which critical habitat 
designation contributes to the undertaking of these efforts, the total 
impact of the effort is quantified, and not a fraction solely due to 
critical habitat designation.
    (32) Comment: The draft economic analysis relies on information 
provided by impacted industries to quantify the costs to those 
industries. These costs are inflated. For example, environmentally 
protective project modifications such as closed-loop systems can result 
in cost savings to the oil and gas industry. The draft economic 
analysis, however, only includes the costs to the industry of modifying 
projects to incorporate conservation measures for the species.
    Our Response: As the commenter notes, the potential for cost 
savings associated with implementing environmentally protective 
technologies, such as closed-loop systems, is acknowledged in the draft 
economic analysis on page 4-7. However, the level of benefit these 
modifications may generate is unclear. Additionally, application of 
closed-loop systems is not ubiquitous. As the industry indicates, it is 
not always the most beneficial operations alternative. The draft 
economic analysis therefore includes the full cost of this modification 
to oil and gas operations as a high-end estimate of the impact of 
conservation efforts.
    (33) Comment: The NMDGF's 2004 Biennial Review of threatened and 
endangered species in the State indicated that off-refuge land use 
practices within areas of the Roswell Artesian Basin (RAB), such as 
regional groundwater pumping for agriculture, municipal water supplies, 
and the oil and gas industries, threaten the invertebrate species. In 
contrast, a recent report prepared by the New Mexico Office of the 
State Engineer (OSE) provides the most recent information regarding the 
hydrology of the RAB. The report concludes that ``* * * an extended, 
extreme drought, and not groundwater depletion through human activity, 
would potentially threaten the future supply of water for the proposed 
critical habitat located within the BLNWR.''
    Our Response: Paragraph 77 and section 4.2.2 of the draft economic 
analysis state that no hydrologic models currently exist to determine 
the impact of groundwater pumping of the RAB on the springs at the 
BLNWR. The revised economic analysis acknowledges recent information 
resulting from the OSE report. As the draft economic analysis does not 
quantify impacts of critical habitat designation to groundwater 
pumping; however, the quantitative results of this analysis are 
unchanged as a result of this comment.

Summary of Changes From the Proposed Rule

    Based upon our review of the public comments, the economic 
analysis, environmental assessment, issues addressed at the public 
hearing, and any new relevant information that may have become 
available since the publication of the proposal, we reevaluated our 
proposed listing and critical habitat designation and made changes as 
appropriate. Other than minor clarifications and incorporation of 
additional information on the species' biology, this final rule differs 
from the proposal by:
    (1) The exclusion of critical habitat on BLNWR because special 
management considerations are currently provided to the four 
invertebrates through current BLNWR management; and
    (2) Changes to the primary constituent elements of critical habitat 
for the Pecos assiminea.

Summary of Factors Affecting the Species

    Section 4 of the Act and implementing regulations (50 CFR 424) set 
forth the procedures for adding species to the Federal lists. A species 
may be determined to be threatened or endangered due to one or more of 
the five factors described in section 4(a)(1) of the Act. These factors 
and their application to the Roswell springsnail, Koster's springsnail, 
Pecos assiminea, and Noel's amphipod are as follows.
    A. The present or threatened destruction, modification, or 
curtailment of its habitat or range.
    Several biological traits of a population have been identified as 
putting a species at risk of extinction (McKinney 1997; O'Grady 2004). 
Some of these characteristics include having a localized range, limited 
mobility, and fragmented habitat (McKinney 1997; O'Grady 2004). The 
four invertebrates have all of these characteristics. Having a small, 
localized range means that any perturbation, either natural (e.g., 
drought) or anthropogenic (e.g., water contamination) can eliminate 
many or all of the existing populations. Having a high number of 
individuals at a site provides no protection against extinction. Noel 
(1954) noted that the amphipod in Lander Spring was the most abundant 
animal present. It was extirpated from that site when the spring dried 
up (Cole 1985). The range reduction trend in these snail species (e.g., 
by extirpation of once widely distributed but localized populations) is 
supported by the Pleistocene fossil record in conjunction with re-
inventory of known site occurrences in which no individuals were 
detected (Noel 1954; Taylor 1987; Mehlhop 1992, 1993; NMDGF 1999). 
Fossil records indicate that at least one or more of these snail 
species were historically found at Berrendo Creek, North Spring, and 
South Spring Rivers, and along the Pecos River (NMDGF 1999). This 
evidence suggests an apparent historical decline in the numbers, range, 
and distribution of these species.

[[Page 46312]]

    Limited mobility restricts the ability of the invertebrates to find 
and disperse to other suitable habitats or to move out of habitat that 
becomes unsuitable. Consequently, their range remains restricted and 
they are unable to avoid contaminants or other unfavorable changes to 
their habitat. Fragmented (unconnected) habitat restricts gene flow 
among populations and limits the ability of the invertebrates to 
recolonize habitats that have been disturbed but then recover. For 
example, three springs once contributed to Berrendo Creek in the 
Roswell Basin. If the population of springsnails in one of the springs 
was eliminated because of a toxic spill, after the habitat had 
recovered, the spring could have been colonized naturally by dispersal 
of animals from the other springs. In the currently fragmented 
habitats, dispersal is highly unlikely and if a population is 
extirpated the habitat probably will not be recolonized, further 
restricting the range.
    In addition to the characteristics listed above that may put 
species at greater risk of extinction, habitat loss, introduced 
species, and habitat degradation can also lead to extinction (Meffe et 
al. 1994; Frankham et al. 2002). Each of these topics is discussed in 
detail. Curtailment of range and habitat of the four invertebrates has 
occurred primarily through the loss of suitable spring habitat. These 
species were most likely much more widely distributed throughout the 
Pecos River Basin during the wetter climatic period of the Pleistocene. 
As the climate became warmer and drier, the invertebrates were 
restricted to the remaining free-flowing springs. Fossil records 
indicate that two of the snail species were found at Berrendo Creek and 
along the Pecos River (Taylor 1987).
    In addition, in the late 1800s, flow at North Spring, South Spring, 
and Berrendo Creek was 85 cubic feet per second (cfs) (2.4 cubic meters 
per second [cms], 60 cfs (1.7 cms), and 66 (1.9 cms) cfs, respectively 
(Fiedler and Nye 1933). These systems each provided abundant habitat 
for the invertebrates. Lander Spring, a tributary spring of South 
Spring, harbored Noel's amphipod (Noel 1954). The historic connection 
of these spring systems to the Pecos River most likely facilitated 
dispersal of the invertebrates throughout the basin downstream of this 
    In the 1880s, irrigated agriculture in the Roswell and Artesia 
Basins was limited to a few small farms (Fielder and Nye 1933). By the 
end of 1905, 485 artesian wells had been drilled and by 1927, 1,424 
wells were pumping water (Fiedler and Nye 1933). One well, drilled for 
the Oasis Cotton Company, is estimated to have produced 9,000 gallons/
minute (20 cfs) (Fiedler and Nye 1933, Jones and Balleau 1996). As a 
result of extensive groundwater pumping, the artesian head in the basin 
declined (Fiedler and Nye 1933). The amount of decline depended on 
location within the basin and ranged from 32 to 204 feet (9.7 to 62.2 
meters) from original levels by 1927, and led to a decrease in area 
within the basin that had artesian flow (Fiedler and Nye 1933). 
Groundwater depletion continued until the mid-1970s, when it reached 
its maximum (McCord et al. 2005).
    By 1926, South Spring was dry (Jones and Balleau 1996). Berrendo 
Spring still produced 8.3 cfs, about 12 percent of the original 1880s 
flow (Jones and Balleau 1996). Today, Berrendo Well produces less than 
1 cfs (McCord et al. 2005). Lander Spring went dry in the late 1950s or 
early 1960s (Cole 1981), extirpating the population of Noel's amphipod, 
which in the early 1950s had been described by Noel (1954) as the most 
abundant animal in the spring. Discharge at North Spring is unknown. 
Jones and Balleau (1996) list its flow as 0 in 1926, but Cole (1981) 
described 3 small separate brooks that entered a pond on a private golf 
course in 1967. Surveys in 1995 at the site indicated that Roswell 
springsnail and Koster's springsnail were still present at the location 
(Noel's amphipod once occupied the site). Surveys in 2004 found none of 
the species, most likely due to habitat modification from pond 
enlargement (NMDGF 2005a). Surface flow at BLNWR was also diminished by 
artesian pumping. Springs adjacent to Salt Creek no longer flow, and 
surface flow from the Middle Area of BLNWR (sum of flow in upper Bitter 
Creek and Middle Area springs) was 15 cfs (0.4 cms) in 1937 and 5 cfs 
(0.14 cms) in 1995 (Jones and Balleau 1996). Aerial photos which show a 
larger, meandering channel for Bitter Creek are also evidence that 
discharge from Bitter Creek was once greater.
    Groundwater pumping in the Roswell Basin led to the drying of 
several springs, many of which are known to have harbored one or more 
of the four invertebrates. It is not possible to determine the extent 
of the loss of invertebrate populations because many springs went dry 
long before these species were described or surveys could be conducted. 
Members of the family Hydrobiidae (including Pyrgulopsis) are 
susceptible to extirpation or extinction because they often occur in 
isolated desert springs (Hershler 1989; Hershler and Pratt 1990; 
Hershler 1994; Lydeard et al. 2004). At least three species in this 
genus have gone extinct (Hershler 1994). In addition, loss can not be 
measured simply by the number of artesian springs that are now not 
flowing. Many of these springs were large enough to form rivers that 
flowed for several miles and creeks such as Bitter Creek, while still 
flowing, are reduced in length. Most likely there was suitable habitat 
available for the invertebrates throughout the length of the streams.
    Groundwater pumping in the Roswell Basin increased through the 
1950s, when approximately 450,000 acre feet/year were extracted (McCord 
et al. 2005). Rates remained fairly stable through 1966 (McCord et al. 
2005). In 1967, water rights were adjudicated in the Roswell Basin, 
wells were metered, and pumping rates administered by the Office of the 
State Engineer (OSE). Currently, any proposed change in use of water 
(underground or surface depletion) in the Roswell Basin will undergo 
analysis by OSE to determine if there would be impairment to existing 
water rights (McCord et al. 2005). The OSE will not allow such change 
if it impairs the Federal water right in any respect (NMISC 2005). Thus 
the spring flows on BLNWR should be protected from any changes in 
groundwater pumping near the Refuge in the future.
    There was a drought in the 1950s that most likely affected the 
recharge of the groundwater in the Roswell Basin. In spite of controls 
on pumping initiated in 1968 and increased precipitation near Roswell 
in the 1960s and 1970s, artesian groundwater levels continued to 
decline until 1975 (McCord et al. 2005). Thus, it appears that there 
was a lag between the time of the drought and recovery in the artesian 
groundwater. Since 1999, New Mexico has been in a drought (Piechota et 
al. 2004). The current drought may also affect groundwater recharge but 
there may be a lag before the effect of the current drought is seen. 
However, through the drought of the 1950s, when pumping was at a 
maximum, several of the springs on BLNWR continued to flow (McCord et 
al. 2005). Groundwater pumping is currently about 100,000 acre feet/
year less than it was during the drought of the 1950s and artesian 
groundwater levels have recovered to the levels they were at in 1950s 
(McCord et al. 2005). Consequently, we expect that there is some added 
margin of protection for the springs through this current drought.
    However, the length or severity of the current drought cycle is not 
known and the Southwest may be entering a period of prolonged drought 
(MaCabe et al. 2004). Droughts of the twentieth century were eclipsed 
in severity by droughts in the last 2000 years, with some

[[Page 46313]]

characterized by longer duration (multidecadal) and greater spatial 
extent (Woodhouse and Overpeck 1998; Piechota et al. 2004). Certainly, 
without groundwater pumping or with pumping at reduced volume there 
would be a greater margin of safety for the springs. But the evidence 
suggests that the springs at BLNWR will flow in spite of relatively 
intense drought (i.e., comparable to the drought of the 1950s) (McCord 
et al. 2005). It is unknown how the springs in Texas would respond to 
extended drought and the current level of groundwater pumping.
    Drought could affect the springs through decreased flow. The 
springs do not have to dry out completely to have an adverse effect on 
populations. Droughts impact both surface and groundwater resources and 
can lead to diminished water quality and disturbed riparian habitats 
(Woodhouse and Overpeck 1998; MacRae et al. 2001). Decreased flow could 
lead to a decrease in habitat availability, increased water 
temperatures, lower dissolved oxygen levels, and an increase in 
salinity (MacRae et al. 2001). Any of these factors, alone or in 
combination, could lead either to the reduction or extirpation of a 
    The primary threat to Pecos assiminea in Texas is the potential 
failure of spring flow due to excessive groundwater pumping and/or 
drought, which would result in total habitat loss for the species. 
Diamond Y Spring is the last major spring still flowing in Pecos 
County, Texas (Service 2005c). Pumping of the regional aquifer system 
for agricultural production of crops has resulted in the drying of most 
other springs in this region (Brune 1981). Other springs that have 
already failed include Comanche Springs, which was once a large spring 
in Fort Stockton, Texas, about 12.9 km (8 mi) from Diamond Y. Comanche 
Springs flowed at more than 142 cfs (4.0 cms) (Brune 1981) and 
undoubtedly provided habitat for rare species of fishes and 
invertebrates, including springsnails. The spring ceased flowing by 
1962 (Brune 1981) except for brief periods (Small and Ozuna 1993). Leon 
Springs, located upstream of Diamond Y in the Leon Creek watershed, was 
measured at 18 cfs (0.5 cms) in the 1930s and was also known to contain 
rare fish, but ceased flowing in the 1950s following significant 
irrigation pumping (Brune 1981). There have been no continuous records 
of spring flow discharge at Diamond Y Spring by which to determine any 
trends in spring flow.
    Studies by Veni (1991) and Boghici (1997) indicate that the spring 
flow at Diamond Y Spring may come from the Rustler aquifers located 
west of the spring outlets. One significant factor that influences 
flows at the spring is the large groundwater withdrawals for 
agricultural irrigation of farms to the southwest in the Belding-Fort 
Stockton areas. Although TNC of Texas owns and manages the property 
surrounding the Diamond Y Springs Complex, it has no control over 
groundwater use that affects spring flow.
    East and West Sandia Springs are at the base of the Davis Mountains 
just east of Balmorhea, Texas, and are part of the San Solomon-
Balmorhea Spring Complex, the largest remaining desert spring system in 
Texas where the Pecos assiminea is found. The springs are included in a 
97-hectare (ha) (240-acre (ac)) preserve owned and managed by TNC 
(Karges 2003). East Sandia Spring discharges at an elevation of 977 
meters (3,224 feet) from alluvial sand and gravel (Schuster 1997). 
Brune (1981) noted that flows from Sandia Springs were declining. East 
Sandia may be very susceptible to over pumping in the area of the local 
aquifer that supports the spring. Measured discharges in 1995 and 1996 
ranged from 0.45 to 4.07 cfs (0.013 to 0.11 cms) (Schuster 1997). The 
small outflow channel from East Sandia Spring has not been 
significantly modified and water flows into an irrigation system 
approximately 100 to 200 meters (328 to 656 feet) after surfacing. West 
Sandia Spring also occurs on the TNC preserve, but it ceased flowing in 
the past 10 years (Schuster 1997).
    Phantom Lake Spring , another spring near the Sandia Springs, has 
experienced a longterm, consistent decline in flow. Discharge data have 
been recorded from the spring six to eight times per year since the 
1940s by the U.S. Geological Survey (Schuster 1997). The record shows a 
steady decline of flows, from greater than 10 cfs (0.28 cms) in the 
1940s to 0 cfs in 2000. The exact causes for the decline in flow from 
Phantom Lake Spring are unknown. Some of the obvious reasons are 
groundwater pumping of the supporting aquifer and decreased recharge of 
the aquifer from drought (Sharp et al. 1999; Sharp et al. 2003). The 
Texas Water Development Board (2005) concluded that because of the 
uncertainties of the regional flow system, it is difficult to assess 
why spring flow in Phantom Lake Spring has declined. Ashworth et al. 
(1997) noted the improper placement of new wells could have a 
detrimental effect on the springs. The Texas Water Development Board 
(2005) agreed with this conclusion. Because of the regional scale of 
the base flow, slow travel time, and the age of the waters issuing from 
the spring system, it is anticipated that any substantial pumping in 
the regional flow system will cause a decline in the spring flow in the 
San Solomon Springs system (including Phantom Lake, San Solomon, 
Giffin, and East Sandia springs) (Texas Water Development Board 2005).

Introduced Species

    One threat not thoroughly explored in our proposed listing is that 
of introduced species. Introduced species are one of the primary 
threats contributing to species' extinction (Pimentel et al. 2000; 
Frankham et al. 2002) and are one of the most serious threats to native 
aquatic species (Williams et al. 1989; Lodge et al. 2000), especially 
in the Southwest (Miller et al. 1989; Minckley and Douglas 1991). It is 
estimated that approximately 50,000 non-native species have been 
introduced into the United States (Pimentel et al. 2000). While some of 
these introductions have been beneficial, many have caused dramatic 
declines in populations of native plants and animals (Pimentel et al. 
2000). Because the distribution of the four invertebrates is so 
limited, and their habitat so restricted, introduction of a non-native 
species into their habitat could be devastating. Several non-native 
species have been very successful in invading spring ecosystems in the 
Southwest. For that reason, we discuss several invasive terrestrial and 
aquatic animal species that are present in the invertebrates' habitat 
or are not yet present but have caused problems in other similar 
habitats in the Southwest and would pose a threat to the four 
invertebrates if they were introduced.
    Several invasive terrestrial plant species that may affect the 
invertebrates are present at BLNWR: saltcedar (Tamarix ramossisima), 
common reed (Phragmites australis), and Russian thistle (tumbleweeds) 
(Salsola spp.). In addition, one non-native, terrestrial snail species 
(Rumina decollata) will be discussed. These plants present unique 
challenges and threats to the habitat the four invertebrates occupy. 
Eradication of saltcedar is an ongoing management effort at BLNWR and 
on TNC property at Diamond Y Spring and East Sandia Springs preserves 
(Service 2005). The species is removed mechanically by hand (young 
sprouts), with heavy equipment for large trees, by cutting and burning, 
or by spraying with herbicides. Control and removal of non-native 
vegetation has previously been identified as a factor responsible for 
extirpation of localized populations of

[[Page 46314]]

Pecos assiminea in Mexico and New Mexico (Taylor 1987).
    Saltcedar is seen as a threat to the spring habitats primarily 
through the amount of water it consumes and from the chemical 
composition of the leaves it drops on the ground and into the springs. 
Invertebrates in small spring ecosystems depend on food from two 
sources: that which grows in or on the substrate (aquatic plants, 
algae, and periphyton) and that which falls or is blown into the system 
(primarily leaves). Leaves from non-native plants that fall into the 
water are often less suitable food sources for invertebrates because of 
either their resins or their physical structure (Bailey et al. 2001). 
Saltcedar leaves add salt to the soil through its leaf litter (the 
leaves contain salt glands) (DiTomosoa 1998). Because saltcedar grows 
along the edge of water courses, it is possible that this could affect 
the soil chemistry of areas inhabited by Pecos assiminea. However, no 
research has been conducted specifically on the effect of saltcedar on 
Pecos assiminea.
    The concentration of common reed at BLNWR has been increasing over 
the last few years and was seen to increase significantly in Bitter 
Creek after the Sandhill fire in 2000 (NMDGF 2005b, 2005c). It is 
unknown if the common reed present at BLNWR is of native origin or if 
it is introduced. Common reed grows in dense patches and reproduces 
primarily through an underwater rhizome (an elongated, horizontal 
stem). Dense stands of the plant choke the channel, slowing water 
velocity and creating more pool-like habitat. Pool-like habitat is less 
suitable for the Roswell and Koster's springsnails, which prefer 
flowing water. In addition, the dense stands of the plant can 
completely shade the water, inhibiting algal growth, one of the food 
items for the springsnails.
    Russian thistle (tumbleweed) is another introduced plant species 
that can create problems within the spring ecosystem. Russian thistle 
is not a riparian species like saltcedar and common reed; however, it 
often ends up in the springs because wind blows the tumbleweeds into 
the spring channels. Noel (1954) noted that she had to pull Russian 
thistle out of Lander Spring so that she could take samples. In 2005, 
BLNWR conducted an emergency Intra-Service section 7 consultation for 
the removal of tumbleweeds from the Area 6 spring ditch. Wind had blown 
the tumbleweeds into the channel to a depth of 0.9 to 1.2 meters (3-4 
feet), completely shading the water and over-loading the small channel 
with organic material. While some amount of organic material from 
outside the spring ecosystem is necessary and desirable, it is not 
desirable to overload the system with so much organic material that it 
cannot be processed. In such situations, dissolved oxygen can drop to 
dangerously low levels as the material decomposes. Primary productivity 
(growth of algae and native aquatic plants like watercress) would be 
greatly reduced or prevented because of shading. Control of introduced 
terrestrial plant species is an on-going management activity at BLNWR 
that will have to be conducted carefully to have the least impact on 
the four invertebrates and their habitat.

Water Quality

    These four species depend upon water for their survival. Therefore, 
water contamination is one of the most serious threats to these 
species. In order to assess the potential for water quality 
contamination, a study was completed in September 1999 to determine the 
sources of water for the springs at BLNWR. This study (Balleau et al. 
1999) reported that the source of water that will reach the BLNWR 
springs over time periods ranging from 10 to 500 years includes a broad 
area beginning west of Roswell near Eightmile Draw, extending to the 
northeast to Salt Creek, and southeast to the BLNWR. Since this area 
delineates the groundwater source area of surface water on the BLNWR, 
it likewise represents pathways for contaminants to enter the species' 
habitat. This broad area sits within a portion of the Roswell Basin and 
contains a mosaic of Federal, State, and private lands with multiple 
land uses, including expanding urban development.
    Contamination of groundwater sources from industry and commercial 
operations in and around Roswell is well documented. For example, 
perchloroethylene (PCE) was discovered in the McGaffey and Main 
groundwater plume in Roswell in 1994 (Environmental Protection Agency 
(EPA) 2001a, 2001b). It is suspected that a dry cleaning facility that 
operated from 1956 to 1963 is the source of the PCE. The New Mexico 
Environment Department subsequently detected PCE in 13 of 16 
groundwater wells in a 1995 investigation (EPA 2001a, 2001b). 
Trichloroethylene was detected in alluvial and artesian aquifers on the 
south side of Roswell, at the former site of the Walker Air Force Base, 
beginning in 1991 (U.S. Army Corps of Engineers, http://www.spa.usace.army.mil/ec/walker-rab/projectinfo.html
). Although there 

is no indication that either of these contaminants will enter springs 
occupied by the four invertebrates, these examples demonstrate that 
groundwater contamination can easily occur and have long-lasting 
    Sediments and fish from Hunter Marsh, located on BLNWR, which 
received municipal wastewater from the City of Roswell, have elevated 
concentrations of polychlorinated biphenyl (PCB), polycyclic aromatic 
hydrocarbons (PAHs), selenium, copper, lead, zinc, and mercury (MacRae 
et al. 2001; Lusk 2005). Fish collected from Hunter Marsh and Hunter 
Oxbow contained PCB concentrations as high as 5 parts per million (ppm) 
(MacRae et al. 2001; Lusk 2005). A diet that contains more than 0.1 ppm 
total PCBs can have adverse effects on wildlife (MacRae et al. 2001). 
PAHs were found at concentrations as high as 7 ppm in sediment and 
fish, which exceeds criteria known to cause adverse effects to aquatic 
organisms (MacRae et al. 2001). Values of PCBs in sediment collected 
from Hunter Marsh are at levels associated with approximately 30 
percent mortality to invertebrates (amphipods) (MacDonald et al. 2000; 
Ingersoll et al. 2000; Lusk 2005).
    Urban development on the west side of BLNWR poses a risk to ground 
and surface water quality from sewage contamination (i.e., septic 
discharge). The largest source of groundwater contamination in New 
Mexico is from household septic tanks and leach fields (NM Water 
Quality Control Commission 2002). Common pollutants associated with 
septic tank contamination include total dissolved solids, iron, 
manganese, sulfides, nitrate, organic chemicals, and microbiological 
contaminants such as bacteria viruses and parasites (NM Water Quality 
Control Commission 2002). Septic leachate is known to have contaminated 
groundwater resources in New Mexico (McQuillan et al. 1989); however, 
specific events have not been documented near BLNWR. Sinkholes west of 
BLNWR have been used for unregulated domestic refuse dumping. Refuse in 
the sinkholes has included domestic contaminants such as pesticides, 
herbicides, and waste oil (Lang 2002). The extent of groundwater 
contaminants generated from residences and illegal dumps near the BLNWR 
is unknown.
    Wastewater from concentrated animal areas (e.g., dairies, feed 
lots, chicken farms), septic tanks, and agricultural uses is a known 
contributor of nitrates to surface and underground water sources (Boyer 
and Pasquarell 1995). Nitrate levels in the underground aquifer near 
Roswell are known to be high. A significant source of the nitrates 
comes from surrounding dairy farms

[[Page 46315]]

(Sarah McGrath, New Mexico State Ground Water Bureau, pers. comm. 
2001). The effects of nitrates on aquatic species are not entirely 
known because several outcomes may result from high-level nitrate 
contamination in aquatic systems. One outcome includes increased growth 

of algae resulting from increased nutrients in the aquatic system. Too 
much algae in an aquatic environment could result in periods of low 
dissolved oxygen and in extreme cases this could be lethal to the 
snails and the amphipod. At least two dairy farms are currently 
required to do remediation for their contribution of nitrates to water 
pollution, both surface and underground (Sarah McGrath, New Mexico 
State Ground Water Bureau, pers. comm. 2001).

Oil and Gas Operations

    Oil drilling occurs throughout the Roswell Basin. This activity and 
associated actions can threaten the water quality of the aquifer on 
which these species depend. For example, oil and other contaminants 
from drilling activities throughout the basin could enter the aquifer 
supplying the springs inhabited by all four species when the limestone 
layers are pierced by drilling activities.
    There are 196 natural gas and oil wells in the 12-township area 
encompassing the source-water capture zone for the Middle Area of BLNWR 
that are potential sources of contamination (New Mexico Petroleum 
Research Center 2002). Of these, 17 oil and gas leases are currently 
within the habitat protection zone, which encompasses 12,585 ac (5,093 
ha) of Federal mineral estate within the water resource area for BLNWR 
(Service 2005a). A total of 20 natural gas wells currently exist on 
these leases. BLM has estimated a maximum potential development of 66 
additional wells within the habitat protection zone, according to well 
spacing requirements established by the New Mexico Oil Conservation 
Division. 48 (Service 2005a). There were 200 (59 on State, 33 on 
Private, and 108 on Federal lands) ``intentions to drill'' (pursuit of 
required permits has been initiated by an applicant) filed for oil or 
natural gas on Federal lands in Chavez County, from 2002 through the 
last update in June 2004 (Go-Tech 2005).
    There are numerous examples in which oil and gas operations have 
employed regulatory standards within the karst lands of the Permian 
Basin in New Mexico and other states, but these measures failed to 
protect groundwater resources and aquifer drawdown (NMISC 2002). To 
remediate (clean) the aquifer would be extremely difficult should it 
become contaminated by oil, chemicals, or organics such as nitrates. In 
most cases contamination of an underground aquifer by agricultural, 
industrial, or domestic sources is treated at the source. When a 
contamination site is discovered, techniques are used to address the 
source of the contamination. Rarely do remediation efforts pump water 
from the aquifer and treat it before sending it back. This is largely 
because these techniques are very costly and difficult to apply (Sarah 
McGrath, New Mexico State Ground Water Bureau, pers. comm. 2001). 
Because these invertebrate species are sensitive to contaminants, 
efforts to clean up pollution source sites after the aquifer has been 
contaminated may not be sufficient to protect these species and the 
aquatic habitat on which they depend.
    Operations associated with oil and gas drilling such as 
exploration, storage, transfer, and refining are also potential threats 
to these species (Jercinovic 1982, 1984; Longmire 1983; Quarles 1983; 
Boyer 1986; Green and Trett 1989; Service 1997). Such extractive 
processes and industry operations are known to contaminate ground and 
surface waters (Jercinovic 1982, 1984; Longmire 1983; Quarles 1983; 
Boyer 1986; Richard 1988a, 1988b; Rail 1989; Richard and Boehm 1989a, 
1989b; Jones and Balleau 1996). Moreover, large volumes of water (about 
12 billion gallons (39,000 acre feet) in 1985) are produced 
concurrently with oil and gas extraction, especially in southeastern 
New Mexico (Boyer 1986). For example, in southeastern New Mexico, the 
average water-to-oil ratio produced in 1985 was 4.5 to 1 (Boyer 1986). 
This water may be injected into the ground in some areas to recover 
more oil, but can also be disposed of in permitted surface pits (Boyer 
1986). This groundwater depletion and ground and surface water 
contamination can adversely impact aquatic mollusks (Eisler 1987, Green 
and Trett 1989) and threaten Roswell springsnail, Koster's springsnail, 
Pecos assiminea, and Noel's amphipod populations at BLNWR (Service 
    Oil and gas activities also threaten the Pecos assiminea because of 
the potential groundwater or surface water contamination from 
pollutants (Veni 1991). The Diamond Y Springs Complex is within an 
active oil and gas extraction field. At this time there are still many 
active wells and pipelines located within a hundred meters of surface 
waters. In addition, a natural gas refinery is located within 0.8 km 
(0.5 mi) upstream of Diamond Y Spring. There are also old brine pits 
associated with previous drilling within feet of surface waters. Oil 
and gas pipelines cross the spring outflow channels and marshes where 
the species occurs, creating a constant potential for contamination 
from pollutants from leaks or spills. These activities pose a threat to 
the habitat of the Pecos assiminea by creating the potential for 
pollutants to enter underground aquifers that contribute to spring flow 
or by point sources from spills and leaks of petroleum products on the 
    As an example of this threat, in 1992 approximately 10,600 barrels 
of crude oil were released from a 6-in (15.2 cm) pipeline that 
traverses Leon Creek above its confluence with Diamond Y Draw. The oil 
was from a ruptured pipeline at a point several hundred feet away from 
the Leon Creek channel. The site itself is about 1 mile (1.6 km) 
overland from Diamond Y Spring. The distance that surface runoff of oil 
residues must travel is about 2 miles (3.2) down Leon Creek to reach 
Diamond Y Draw. The pipeline was operated at the time of the spill by 
the Texas-New Mexico Pipeline Company, but ownership has since been 
transferred to several other companies. Texas Railroad Commission has 
been responsible for overseeing cleanup of the spill site. Remediation 
of the site initially involved aboveground land farming of contaminated 
soil and rock strata to allow microbial degradation. In recent years, 
remediation efforts have focused on vacuuming oil residues from the 
surface of groundwater exposed by trenches dug at the spill site. To 
date, no impacts on the rare fauna of Diamond Y Springs Complex have 
been observed, but no specific monitoring of the effects of the spill 
was undertaken (Service 2005b).
    B. Overutilization for commercial, recreational, scientific, or 
educational purposes. Roswell springsnail, Koster's springsnail, Pecos 
assiminea, and Noel's amphipod may occasionally be collected as 
specimens for scientific study, but these uses probably have a 
negligible effect on total population numbers. These species are 
currently not known to be of commercial value, and overutilization has 
not been documented. However, as their rarity becomes known, they may 
become more attractive to collectors. Although scientific collecting is 
not presently identified as a threat, unregulated collecting by private 
and institutional collectors could pose a threat to these locally 
restricted populations. We are aware of overcollection being a 
potential threat with other snails (e.g., armored snail (Pyrgulopsis 
(Marstonia) pachyta) (65 FR 10033, February 25, 2000); Bruneau hot 
springsnail (P.

[[Page 46316]]

bruneauensis) (58 FR 5938, January 25, 1993); and Socorro springsnail 
(P. neomexicana) and Alamosa springsnail (Tryonia alamosae) (56 FR 
49646, September 30, 1991)), due to their rarity, restricted 
distribution, and generally well known locations. Due to the small 
number of localities for the snails and the amphipod, these species are 
vulnerable to unrestricted collection, vandalism, or other disturbance. 
There is no documentation of collection as a significant threat to any 
of the species. Therefore, we believe that collection of the animals is 
a minor but present threat.
    C. Disease or predation. Springsnails and amphipods are a food 
source for other aquatic animals. Juvenile springsnails appear 
vulnerable to a variety of predators. Damselflies (Zygoptera) and 
dragonflies (Anisoptera) were observed feeding upon snails in the wild 
(Mladenka 1992). Damselflies and dragonflies are native to and abundant 
at BLNWR and most likely prey upon both the springsnails and Noel's 
    Springsnails are vulnerable to predation by fish (Kennedy 1977; 
Winemiller and Anderson 1997). Mladenka (1992) observed guppies feeding 
on springsnails in the laboratory. The non-native fish present at BLNWR 
(carp and mosquitofish) most likely also prey upon the springsnails and 
Noel's amphipod when they occur in the same habitats. The extent to 
which predation from non-native fish affects population size of the 
three aquatic invertebrates is not known. Predation pressure on Pecos 
assiminea is also unknown. However, if the land snail Rumina becomes 
established at BLNWR, the potential exists for it to predate on Pecos 
    Infestation by trematodes (a flatworm or fluke, phylum 
Platyhelminthes) was noted by Taylor (1987) in populations of Koster's 
springsnail at Sago Spring, BLNWR. Digenetic trematodes (trematodes in 
the order Digenera) are parasitic and have the most complicated life 
histories in the animal kingdom involving two to four intermediate 
(vertebrate and/or invertebrate) hosts (Hickman et al. 1974). The first 
larval stage of the trematode nearly always uses a mollusk (snail or 
bivalve) as the first intermediate host (Hickman et al. 1974). Larval 
trematode parasites reduce or completely inhibit snail reproduction 
through castration (Minchella et al. 1985). The effect of the 
trematodes on the springsnail population is not known.
    The terrestrial land snail (Rumina decollate) was introduced to the 
United States in the early 1800s in South Carolina and spread westward 
(Selander and Kaufman 1973). It was reported in Arizona in 1952 and 
California in 1966 but was well-established by the time it was 
discovered (Selander and Kaufman 1973). It is common in Texas (Selander 
and Kaufman 1973) and has been reported from the Roswell area in New 
Mexico (Lang 2005b). It inhabits gardens and agricultural areas but has 
also invaded riparian and other native habitats (Selander and Kaufman 
1973). It is used in California as a biological control agent against 
the brown garden snail (Helix aspera) (Cowie 2001). It will consume 
native snails (Cowie 2001) as well as vegetation (Dundee 1984). For 
these reasons, Rumnia is a potential threat to Pecos assiminea.
    Non-native aquatic species such as crayfish, fish, and aquatic 
snails are also a potential threat to the four invertebrates. There is 
only one species of crayfish native to New Mexico, but its distribution 
does not overlap with that of the four invertebrates (Hobbs 1991). 
Crayfish are typically opportunistic generalists (they will eat 
anything and everything) (Hobbs 1991). Predation on invertebrates is 
well-documented (Hobbs 1991; Lodge et al. 1994; Charlebois and Lamberti 
1996; Strayer 1999). However, because they also feed on organic debris 
and vegetation and reduce algal biomass (Charlebois and Lamberti 1996), 
they could potentially compete with Roswell springsnail, Koster's 
springsnail, and Noel's amphipod for food resources. Currently non-
native crayfish are not present at BLNWR or the sites in Texas. Diamond 
Y Springs Complex does have an undescribed native crayfish which we do 
not believe to be a concern for Pecos assiminea. However, crayfish have 
created major problems in aquatic systems in Arizona, and there is no 
physiological reason why some species of crayfish could not survive in 
the habitats that now support the four invertebrates. Eradication of 
crayfish once they are established is extremely difficult (Hyatt 2004). 
Diamond Y Springs Complex has an undescribed native crayfish which we 
do not believe to be a concern for Pecos assiminea.
    Non-native fish have had a major impact on native aquatic fauna in 
the Southwest (Minckley and Douglas 1991; Desert Fishes Team 2003). 
Communities of animals evolved together and developed adaptations to 
deal with competition and predation from other members of the community 
(Meffe et al. 1994). When a non-native species is introduced into this 
community the native members often do not have defenses against 
predation or they may be less successful competitors. As a result, the 
non-native species can have a major impact on native populations 
(Minckley and Douglas 1991; Meffe et al. 1994). One species of non-
native fish, common carp (Cyprinus carpio), is known to co-occur with 
the three aquatic invertebrates at BLNWR. Native to Asia, common carp 
was introduced into the United States in 1831, has become widely 
distributed (Sublette et al. 1990), and is present at BLNWR in habitats 
occupied by the invertebrates. Through spawning and feeding behavior it 
uproots vegetation and increases turbidity (Sublette et al. 1990). It 
is an omnivore feeding on aquatic invertebrates, fish eggs, algae, 
plants, and organic matter (Sublette et al. 1990). Because of its non-
discriminatory diet and habitat disturbance, it could have an impact on 
the three aquatic invertebrate species.
    Mosquitofish (Gambusia affinis) is also present in some of the 
spring systems at BLNWR, but it is not known if it is native to the 
area or not. The species is native to portions of New Mexico but it has 
also been widely introduced to control mosquitoes (Sublette et al. 
1990). However, it has negatively affected or extirpated many species 
of fish and invertebrates (e.g., through predation) (Meffe et al. 
1994). It is not known if mosquitofish are affecting the three species 
of aquatic invertebrates.
    Non-native mollusks have affected the distribution and abundance of 
native mollusks in the United States. Of particular concern for three 
of the invertebrates (Noel's amphipod, Roswell springsnail, and 
Koster's springsnail) are Melanoides tuberculata (red-rim melania) and 
Potamopyrgus antipodarum (New Zealand mudsnail). Both of these snails 
are excellent colonizers that reach tremendous population sizes and 
have been found in isolated springs in the West. Melanoides has caused 
the decline and local extirpation of native snail species, and it is 
considered a threat to endemic aquatic snails that occupy springs and 
streams in the Bonneville Basin of Utah (Rader et al. 2003). It is 
easily transported on gear or aquatic plants, and because it reproduces 
asexually (individuals can develop from unfertilized eggs), a single 
individual is capable of founding a new population. It has become 
established in isolated desert spring ecosystems such as Ash Meadows, 
Nevada, and Cuatro Cinegas, Mexico, and within the last 10 years, 
Melanoides has become established in Diamond Y Springs Complex (Echelle 
2001; McDermott 2000). It has become the most abundant snail in the 
upper watercourse of the Diamond Y Springs

[[Page 46317]]

Complex (Echelle 2001). In many locations, this exotic snail is so 
numerous that it essentially is the substrate in the small stream 
channel. The effect Melanoides is having on native snails is not known; 
however, because it is aquatic it probably has less effect on Pecos 
assiminea than on the other endemic aquatic snails present in the 
    Potampyrgus is also a potential threat to the endemic aquatic 
snails at BLNWR and the spring systems in Texas. It was discovered in 
the Snake River, Idaho, in the mid-1980s and has quickly spread to 
every Western state except New Mexico (Montana State University http://www.esg.montana.edu/aim/mollusca/nzms/status.html
, accessed on June 16, 

2005). Like Melanoides, Potamopyrgus has an operculum (a lid to close 
off the shell opening), can withstand periods of drying up to 8 days 
(thereby facilitating transport) and can reproduce either sexually or 
asexually. Thus, new populations can be established with transport of a 
single individual. In addition, Potampyrgus is tiny (3 mm in height 
[0.12 in]), is easily overlooked on gear or shoes, and can be 
transported unknowingly by people visiting various recreational sites. 
Considering its current rate of expansion, and the availability of 
suitable habitat, it is highly likely that Potampyrgus will soon be 
discovered in New Mexico.
    Potampyrgus tolerates a wide range of habitats, including brackish 
water. Densities are usually highest in systems with high primary 
productivity, constant temperatures, and constant flow (typical of 
spring systems). It has reached densities exceeding 500,000 
m2 (Richards et al. 2001) to the detriment of native 
invertebrates. Not only can it dominate the invertebrate assemblage (97 
percent of invertebrate biomass), it can also eat nearly all of the 
algae and diatoms growing on the substrate, altering ecosystem function 
at the base of the food web (food is no longer available for native 
animals) (Hall et al. 2003). If Potampyrgus is introduced into the 
spring systems harboring the proposed invertebrates, control would most 
likely be impossible because the snails are so small and because any 
chemical treatment would also affect the native species. The impact 
could be devastating.
    D. The inadequacy of existing regulatory mechanisms. One primary 
cause of decline of the Roswell springsnail, Koster's springsnail, 
Pecos assiminea, and Noel's amphipod is the loss, degradation, and 
fragmentation of habitat due to human activities. Federal and State 
laws have been insufficient to prevent past and ongoing losses of the 
limited habitat of the four invertebrates, and are unlikely to prevent 
further declines of the species.


    Clean Water Act. Pursuant to section 404 of the Clean Water Act 
(CWA) (33 U.S.C. 1344), the U.S. Army Corps of Engineers (Corps) 
regulates the discharge of dredged or fill material into all Waters of 
the United States, including wetlands. In general, the term 
``'wetland''' refers to areas meeting the Corps criteria of having 
hydric soils, hydrology (either a defined minimum duration of 
continuous inundation or saturation of soil during the growing season), 
and a plant community that is predominantly hydrophytic vegetation 
(plants specifically adapted for growing in a wetland environment). The 
spring complexes occupied by these four invertebrates qualify as 
    Any discharge of dredged or fill material into waters of the United 
States, including wetlands, requires a permit from the Corps. These 
include individual permits which would be issued following a review of 
an individual application, and general permits that authorize a 
category or categories of activities in a specific geographical 
location or nationwide (33 CFR parts 320-330). General and special 
permit conditions may vary among individual Corps Districts and the 
various general permits. However, the use of any individual or general 
permit requires compliance with the Act.
    While the CWA provides a means for the Corps to regulate the 
discharge of dredged or fill material into waters and wetlands of the 
United States, it does not provide complete protection. Many applicants 
are required to provide compensation for wetlands losses (i.e., no net 
loss) and many smaller impact projects remain largely unmitigated 
unless specifically required by other environmental laws such as the 
Act. Moreover, we are not aware of any Corps permits that have been 
issued for the spring complexes where these species occur or 
historically occurred, indicating that there is little protection 
provided to these species through the CWA.
    Recent court cases limit the Corps' ability to utilize the CWA to 
regulate the discharge of fill or dredged material into the aquatic 
environment within the current range of the Roswell springsnail, 
Koster's springsnail, Pecos assiminea, and Noel's amphipod (Solid Waste 
Agency of Northern Cook County v. U.S. Army Corps of Engineers, 531 
U.S. 159 (2001) (SWANCC)). There may be instances where seasonal 
wetlands used by California tiger salamander lack sufficient connection 
to waters of the United States for the Corps to assert jurisdiction 
under the authority of the Clean Water Act. For example, the Corps 
frequently cites the SWANCC decision as their reason for not taking 
jurisdiction over waterbodies that do not meet the definition of waters 
of the United States. For these reasons, we conclude that regulation of 
wetlands filling by the Corps under Section 404 of the CWA is 
inadequate to protect the Roswell springsnail, Koster's springsnail, 
Pecos assiminea, and Noel's amphipod from further decline.
    Revisions to the Roswell Approved Resource Management Plan made by 
BLM in 1997 prompted a formal section 7 consultation with the Service 
regarding the endangered Pecos gambusia (Gambusia nobilis), which 
resides on BLNWR. The BLM designated an area for protection of habitat 
for Pecos gambusia from potential groundwater contamination by oil and 
gas well drilling operations (BLM 2002). This area, referred to as the 
Habitat Protection Zone (HPZ), includes a portion of the source-water 
capture area for the springs in the northern part of the Middle Tract 
of BLNWR, where Pecos gambusia co-occurs with the four invertebrate 
species. The HPZ includes 12,585 ac (5,093 ha) of the Federal mineral 
estate and 9,945 ac (4,025 ha) of the Federal surface estate that are 
within the water source area for the BLNWR. The HPZ was established in 
October of 2002 and special requirements for oil and gas well 
development managed to protect the ground and surface water resources 
(BLM 2002). For example, stipulations for oil and gas wells in the HPZ 
include storage of drilling muds in steel tanks and use of cement to 
seal the entire length of the well casing. These requirements reduce 
the probability of contamination from oil and gas development but do 
not reduce the likelihood of groundwater contamination attributable to 
oil and gas storage or transportation activities (e.g. leaking 
pipelines, storage tanks, or other equipment failures). Therefore, the 
HPZ does not eliminate the threat of oil and gas activities on these 
species, nor does it address the other threats identified under Factor 
A (e.g., drought, septic tank leaching, etc).


    Existing New Mexico State regulatory mechanisms are inadequate to 
protect the Roswell springsnail, Koster's springsnail, Pecos assiminea, 
and Noel's amphipod. All four species are listed as New Mexico State 
endangered species, Group 1, which are those species ``whose prospects 
of survival or

[[Page 46318]]

recruitment within the State are in jeopardy.'' This designation 
provides the protection of the New Mexico Wildlife Conservation Act, 
but only prohibits direct take of these species, except under issuance 
of a scientific collecting permit. New Mexico State statutes do not 
address habitat protection, indirect effects, or other threats to these 
species. New Mexico State status as an endangered species only conveys 
protection from collection or intentional harm. However, there is no 
formal consultation process to address the habitat requirements of the 
species or how a proposed action may affect the needs of the species. 
Because most of the threats to these species are from effects to 
habitat, protecting individuals will not ensure their long-term 
    NMDGF recognizes the importance of Roswell springsnail, Koster's 
springsnail, Pecos assiminea, and Noel's amphipod conservation at the 
local population level and has the authority to consider and recommend 
actions to mitigate potential adverse effects to these species during 
its review of development proposals. As noted, NMDGF's primary 
regulatory venue is under the New Mexico Wildlife Conservation Act. 
There are no statutory requirements under NMDGF's jurisdiction that 
serve as an effective regulatory mechanism for reducing or eliminating 
the threats (see Factors A and C above) that may adversely affect 
Roswell springsnail, Koster's springsnail, Pecos assiminea and their 
    Still, New Mexico State statutes require the NMDGF to develop a 
recovery plan that will restore and maintain species' habitat. A 
recovery and conservation plan for the four invertebrates was finalized 
by the State of New Mexico in January 2005 (NMDGF 2005b). The plan 
provides details about the natural history of the invertebrates, a 
historical perspective of habitat and population trends, and habitat 
assessment. The goal of the plan is to ensure that the invertebrates 
occur in sufficient numbers within populations and in a sufficient 
number of discrete and independent populations, that downlisting and 
eventual delisting under the Wildlife Conservation Act is warranted 
(NMDGF 2005b). The plan outlines three parameters to meet the goal: (1) 
Maintenance or expansion of the existing distribution and abundance of 
the invertebrates at BLNWR; (2) repatriation of the invertebrates to 
restored suitable habitat at two or more sites within their known 
historic range; and (3) establishment and stocking of an artificial and 
secure refugium to protect against catastrophic loss in the wild (NMDGF 
2005b). As noted above, the State's recovery plan does not ensure any 
long-term protection for these species because there are no mandatory 
elements to ensure proposed projects do not adversely affect these 
species or their habitat.
    The Oil Conservation Division of the New Mexico Energy, Minerals, 
and Natural Resources Department regulates oil and gas well drilling 
and casing in part to prevent contamination of groundwater (19 NMAC 
15.3). Although there are no known instances of groundwater 
contamination by leaking oil or gas wells in the source-water capture 
zone for the Middle Unit of BLNWR, there is a well documented history 
of oil and gas industry operations on and adjacent to BLNWR, which have 
resulted in the spillage of oil and brine onto the BLNWR (Service 
1994b, 1996, 1997a, 1998b). Therefore, we find that these regulations 
provide some protection to the four invertebrates, but do not eliminate 
the threat of oil spills through accidents or equipment malfunctions.
    The environmental assessment found that spring flows within the 
proposed critical habitat on BLNWR are already protected by existing 
water rights afforded by the New Mexico Office of the State Engineer's 
administration of the Roswell Basin. In 1967, water rights were 
adjudicated in the Roswell Basin, wells were metered, and pumping rates 
administered by the Office of the State Engineer (OSE). Currently, any 
proposed change in use of water (underground or surface depletion) in 
the Roswell Basin will undergo analysis by OSE to determine if there 
would be impairment to existing water rights (McCord et al. 2005). The 
OSE will not allow such change if it impairs the Federal water right in 
any respect (NMISC 2005). Thus the spring flows on BLNWR should be 
protected from any changes in groundwater pumping near the refuge in 
the future. This provides a regulatory benefit to the four 
    However, we believe that there was a lag between the time of the 
drought and recovery in the artesian groundwater in this area. Because 
New Mexico has been in a drought since 1999, there may be a lag time 
before the effect of the current drought is observed. We believe that 
the springs on BLNWR will flow in spite of relatively intense drought 
(McCord et al. 2005). However, it is not known how the springs in Texas 
would respond to extended drought and the current level of groundwater 
pumping. Moreover, the habitat occupied by the four invertebrates does 
not have to dry out completely to have an effect on populations. Lower 
spring flows may cause a decrease in habitat availability, increased 
water temperatures, lower dissolved oxygen levels, and an increase in 
salinity (MacRae et al. 2001). Any of these factors, alone or in 
combination, could lead either to the reduction or extirpation of a 
population. Additionally, the primary threat to Pecos assiminea in 
Texas is the potential failure of spring flow due to excessive 
groundwater pumping and/or drought, which would result in total habitat 
loss for the species.
    In Texas, Pecos assiminea currently has no State or other 
regulatory protection. Some protection for the habitat of this species 
is provided with the ownership of the springs by TNC (Karges 2003). 
However, this land ownership provides no protection from one of the 
main threats to this species--the loss of necessary groundwater levels 
to ensure adequate spring flows. Groundwater pumping that could affect 
spring flows is subject to limited regulation in Texas. State agencies 
do not control groundwater pumping, and Texas courts have held that, 
with few exceptions, landowners have the right to take all the water 
that can be captured under their land (rule of capture), regardless of 
impacts to neighbors or natural resources. Individual groundwater 
conservation districts have varying amounts of authority and capacity 
to limit pumping. Diamond Y Spring is within the jurisdiction of the 
Middle Pecos Groundwater Conservation District, but generally 
groundwater districts will not limit groundwater use to allow for 
conservation of surface water flows (Booth and Richard-Crow 2004; 
Caroom and Maxwell 2004). Thus, we find no existing regulatory 
mechanisms in place to protect the Pecos assiminea.
    Members of the four invertebrate species that co-exist in springs 
with the federally endangered Pecos gambusia (Gambusia nobilis) at 
BLNWR and Diamond Y Spring and the federally endangered Leon Springs 
pupfish at Diamond Y Spring may receive incidental habitat protection 
from the Act. However, possible habitat protection provided by the 
federally listed Pecos gambusia and the Leon Springs pupfish offers 
only partial protection for the Roswell springsnail, Koster's 
springsnail, Pecos assiminea, and Noel's amphipod because the federally 
listed fish are not found in all the springs the snails or amphipod 
inhabit. For example, Pecos assiminea does not normally occur directly 
within submerged habitats. It is most

[[Page 46319]]

commonly found in moist soil or vegetation along the periphery of 
standing water. As a result, this habitat may not be afforded 
protection under current management actions or consultations which 
address conservation for listed fish species in the same area.
    Federal water-rights for the BLNWR were secured in 1996 (Service 
2005b). This acquisition should ensure minimum surface water discharge 
of Bitter Creek. However, if this water is contaminated, the Federal 
water right alone does not provide adequate protection for these 
    E. Other natural or manmade factors affecting its continued 
existence. BLNWR was established in 1937 as wintering and breeding 
grounds for migratory birds. At the time the four invertebrates were 
unknown to science. Consequently, management was directed primarily at 
creating dikes so that ponds could be created and their water levels 
controlled for the benefit of waterfowl. Some of the ponds created 
would seasonally flood springs that flowed into these ponds naturally. 
Because the Roswell springsnail and Noel's amphipod, in particular, 
prefer flowing over pooled water, this had a negative impact on the 
habitat available to them. In 2003, a dike rehabilitation project was 
begun on BLNWR. Two dikes running the length of Areas 6 and 7 were 
constructed. This isolated the spring systems from the main body of the 
impoundments, allowing the areas to be flooded in the winter without 
inundating the springs occupied by the invertebrates. In addition, 
potential habitat for the invertebrates was created in a new ditch 
designed to carry water to Area 7. Current management of BLNWR 
recognizes and includes the invertebrates in its maintenance and 
operations, and is no longer a threat to the invertebrates.


    BLNWR is characterized by sinkhole/karst terrain. This terrain 
poses safety threats to fire crews and suppression equipment. As a 
result, fire suppression efforts are largely restricted to established 
roads. This severely limits management ability to quickly suppress 
fires that threaten fragile aquatic habitats on the BLNWR. On March 5, 
2000, the Sandhill fire burned 405 ha (1,000 ac) of the western portion 
of the BLNWR, including portions of Bitter Creek. The fire burned 
through Dragonfly Spring, eliminated vegetation shading the spring, and 
generated a substantial amount of ash in the spring system (Lang 2000, 
NMDGF 2005b, 2005c). Subsequently, dense algal mats formed, water 
temperature fluctuations and maximum temperatures increased, while 
dissolved oxygen levels decreased (Lang 2002). The pre-fire dominant 
vegetation of submerged aquatic plants and mixed native grasses within 
the burned area has also been replaced by the invasive common reed 
(NMDGF 2005b, 2005c). Following the fire, a dramatic reduction in 
Noel's amphipod was observed, and Koster's springsnail occurs at lower 
densities than were observed prior to the fire (Lang 2002, NMDGF 
    Currently, dense stands of common reed are found throughout most 
reaches of Bitter Creek, including in habitat occupied by the four 
invertebrates (NMDGF 2005c) (see also ``Factor C'' section above). 
Prior to the Sandhill Fire, common reed occurred only sporadically 
along Bitter Creek (NMDGF 2005c). These dense stands of common reed 
have increased the fuel load and threat of wildfire on BLNWR. Standing 
dead canes of common reed and associated litter often constitute twice 
as much biomass as living shoots (Uchytil 1992). This abundant dead 
fuel carries fire well, allowing stands to burn even when the current 
year's shoots are green (Uchytil 1992). Because of the increase in 
common reed on BLNWR within habitat occupied by the four invertebrates, 
we now find that wildfire is a threat to the four invertebrates.
    Removal of vegetative cover by burning in habitats occupied by 
Pecos assiminea may be an important factor in decline or loss of 
populations (Taylor 1987). Alternatively, Pecos assiminea has been 
found to persist in areas following fires (Lang 2000). Pecos assiminea 
was also discovered at Dragonfly Spring following burning of habitat 
there during the Sandhill Fire (NMDGF 2005a). Season of burning, 
intensity of the fire, and frequency of fire are likely important 
determinants of effects on population persistence and abundance of 
Pecos assiminea (NMDGF 1998). Pecos assiminea is potentially more 
vulnerable to fires than the springsnails because they reside at or 
near the surface of the water. However, it is thought that Pecos 
assiminea may survive fire or other vegetation reduction if sufficient 
litter and ground cover remain to sustain appropriate soil moisture and 
humidity at a microhabitat scale (NMDGF 2005a; Service 2004).
    Controlled burns have been implemented on BLNWR to burn grass, 
sedge, cattail, and non-native vegetation (e.g., Russian thistle) in an 
attempt to reduce the risk of large uncontrolled wildfires or to remove 
excessive amounts of Russian thistle from a spring run (Service 2004). 
We have found that controlled burns with appropriate conservation 
measures do not adversely affect the Koster's springsnail, Pecos 
assiminea, or Roswell springsnail (Service 2004). On the other hand, 
prescribed burns to remove Russian thistle may have indirectly affected 
Noel's amphipod through the release of common reeds, which can reduce 
water flow and result in decreased dissolved oxygen levels (Service 
2005c). Surveys conducted immediately post-fire indicate that Noel's 
amphipod is still found throughout the burned area, with little to no 
direct effects (Service 2005c). Still, the Service is continuing to 
monitor post-fire effects from these activities to determine if Noel's 
amphipod has been adversely affected.
    Fire, particularly during the winter months, will allow ash, 
sediment, salts, and nutrients to more readily enter the aquatic 
habitat via precipitation and wind. Ash consists of carbon, soots, and 
other organic compounds that, upon entering the water column, provide a 
food source for bacteria and algae. With the addition of associated 
nutrients, and water temperature increases from the loss of streamside 
vegetation, populations of bacteria and algae will expand, causing 
oxygen depletions. As a result, some invertebrates may perish in these 
situations, where they cannot escape the oxygen deficit. Additionally, 
denuded areas will allow erosion and sedimentation of the streamside 
habitat. Sedimentation could have the direct effect on the Roswell 
springsnail, which is typically found on rocks.


    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
faced by these species in determining that these species are in danger 
of extinction throughout all or a significant portion of their 
respective ranges. The habitat and range of Roswell springsnail, 
Koster's springsnail, Pecos assiminea, and Noel's amphipod are 
threatened with destruction, modification, and curtailment. Existing 
regulatory mechanisms do not provide adequate protection for these 
species, and other natural and manmade factors affect their continued 
existence. Because each of these four species has a very limited range, 
their populations are disjunct and isolated from each other, and 
potential habitat areas are isolated and separated by large areas of 
unsuitable habitat, these invertebrates are particularly vulnerable to 
localized extinction should their habitat be degraded or destroyed. 
Because their mobility is limited, populations will have little 
opportunity to leave

[[Page 46320]]

degraded habitat areas in search of suitable habitat. As a result, one 
contamination event, or a short period of drawdown in the aquatic 
habitat where they are found could result in the loss of an entire 
population, of which there are few. Because of the limited distribution 
of these endemic species, any impact from increasing threats (e.g., 
loss of springflow, contaminants, nonnative species) is likely to 
result in their extinction because the magnitude of threat is high. 
These species occur in an arid region plagued by drought and ongoing 
aquifer withdrawals (e.g., in Texas), making the loss of springflows an 
imminent threat in the foreseeable future. We also found that their 
habitat faces a constant threat from water quality contamination. 
Therefore, we have determined that the Roswell springsnail, Koster's 
springsnail, Pecos assiminea, and Noel's amphipod meet the definition 
of an endangered species pursuant to section 3 of the Act. A threatened 
species designation as defined in section 3 of the Act would not 
accurately reflect the population status, restricted distribution, 
vulnerability, and imminent threats. As such, we are listing these four 
invertebrate species as endangered under the Act.

Critical Habitat

Designation of Critical Habitat Provides Little Additional Protection 
to Species

    In 30 years of implementing the Act, the Service has found that the 
designation of statutory critical habitat provides little additional 
protection to most listed species, while consuming significant amounts 
of conservation resources. The Service's present system for designating 
critical habitat is driven by litigation rather than biology, limits 
our ability to fully evaluate the science involved, consumes enormous 
agency resources, and imposes huge social and economic costs. The 
Service believes that additional agency discretion would allow our 
focus to return to those actions that provide the greatest benefit to 
the species most in need of protection.

Role of Critical Habitat in Actual Practice of Administering and 
Implementing the Act

    While attention to and protection of habitat is paramount to 
successful conservation actions, we have consistently found that, in 
most circumstances, the designation of critical habitat is of little 
additional value for most listed species, yet it consumes large amounts 
of conservation resources. Sidle (1987) stated, ``Because the Act can 
protect species with and without critical habitat designation, critical 
habitat designation may be redundant to the other consultation 
requirements of section 7.''
    Currently, only 445 species, or 36 percent, of the 1,244 listed 
species in the United States under the jurisdiction of the Service have 
designated critical habitat. We address the habitat needs of all 1,244 
listed species through conservation mechanisms such as listing, section 
7 consultations, the Section 4 recovery planning process, the section 9 
protective prohibitions of unauthorized take, section 6 funding to the 
States, and the section 10 incidental take permit process. The Service 
believes that it is these measures that may make the difference between 
extinction and survival for many species.
    We note, however, that a recent 9th Circuit judicial opinion, 
Gifford Pinchot Task Force v. United States Fish and Wildlife Service, 
has invalidated the Service's regulation defining destruction or 
adverse modification of critical habitat. We are currently reviewing 
the decision to determine what effect it may have on the outcome of 
consultations pursuant to section 7 of the Act.
Procedural and Resource Difficulties in Designating Critical Habitat
    We have been inundated with lawsuits regarding critical habitat 
designation, and we face a growing number of lawsuits challenging 
critical habitat determinations once they are made. These lawsuits have 
subjected the Service to an ever-increasing series of court orders and 
court-approved settlement agreements, compliance with which now 
consumes nearly the entire listing program budget. This leaves the 
Service with little ability to prioritize its activities to direct 
scarce listing resources to the listing program actions with the most 
biologically urgent species conservation needs.
    The consequence of the critical habitat litigation activity is that 
limited listing funds are used to defend active lawsuits and to comply 
with the growing number of adverse court orders. As a result, the 
Service's own proposals to undertake conservation actions based on 
biological priorities are significantly delayed.
    The accelerated schedules of court ordered designations have left 
the Service with almost no ability to provide for meaningful additional 
public participation beyond those minimally required by the 
Administrative Procedure Act (APA), the Act, and the Service's 
implementing regulations, or to take additional time for review of 
comments and information to ensure the rule has addressed all the 
pertinent issues before making decisions on listing and critical 
habitat proposals, due to the risks associated with noncompliance with 
judicially imposed deadlines. This in turn fosters a second round of 
litigation in which those who will suffer adverse impacts from these 
decisions challenge them. The cycle of litigation appears endless, is 
very expensive, and in the final analysis provides little additional 
protection to listed species.
    The costs resulting from the designation include legal costs, the 
cost of preparation and publication of the designation, the analysis of 
the economic effects and the cost of requesting and responding to 
public comment, and in some cases the costs of compliance with the 
NEPA; all are part of the cost of critical habitat designation. These 
costs result in minimal benefits to the species that are not already 
afforded by the protections of the Act enumerated earlier, and they 
directly reduce the funds available for direct and tangible 
conservation actions.
    Section 3(5)(A) of the Act defines critical habitat as the specific 
areas within the geographical area occupied by the species on which are 
found those physical and biological features (I) essential to the 
conservation of the species and (II) which may require special 
management considerations or protection and that the designation of 
critical habitat for a given species is prudent and determinable. 
``Conservation'' means the use of all methods and procedures that are 
necessary to bring an endangered or a threatened species to the point 
at which listing under the Act is no longer necessary. Because we 
proposed critical habitat for the four invertebrates, we already 
determined that critical habitat pursuant to the Act and implementing 
regulations was both prudent and determinable (67 FR 6459).
    Section 3(5)(c) of the Act states that not all areas that can be 
occupied by a species should be designated as critical habitat unless 
the Secretary determines that all such areas are essential to the 
conservation of the species. Our regulations (50 CFR 424.12(e)) also 
state that ``The Secretary shall designate as critical habitat areas 
outside the geographical area presently occupied by the species only 
when a designation limited to its present range would be inadequate to 
ensure the conservation of the species.''
    Areas within the geographical area occupied by the species that do 
not contain the features essential for the conservation of the species 
are not, by

[[Page 46321]]

definition, critical habitat. Similarly, within the geographical area 
occupied by the species, if the features essential for the conservation 
of the species will not require special management considerations or 
protection, the area is not, by definition, critical habitat. To 
determine whether the essential features within an area may require 
special management, we first determine if the essential features 
located there generally require special management to address 
applicable threats. If those features do not require special 
management, or if they do in general but not for the particular area in 
question because of the existence of an adequate management plan or for 
some other reason, then the essential features within the area do not 
require special management.
    Further, section 4(b)(2) of the Act states that critical habitat 
shall be designated, and revised, on the basis of the best available 
scientific data after taking into consideration the economic impact, 
impact on national security, and any other relevant impact of 
specifying a particular area as critical habitat. An area may be 
excluded from critical habitat if it is determined that the benefits of 
exclusion outweigh the benefits of specifying a particular area as 
critical habitat, unless the failure to designate such area as critical 
habitat will result in the extinction of the species.
    The designation of critical habitat does not affect land ownership 
or establish a refuge, wilderness, reserve, preserve, or other 
conservation area. It does not allow government or public access to 
private lands. Under section 7 of the Act, Federal agencies must 
consult with the Service on activities they undertake, fund, or permit 
that may affect critical habitat and lead to its destruction or adverse 
modification. However, the Act prohibits unauthorized take of listed 
species and requires consultation for activities that may affect them, 
including habitat alterations, regardless of whether critical habitat 
has been designated.
    When a Federal nexus exists, we work with the appropriate Federal 
agency, and in some cases the applicant to the consultation, to ensure 
that the project can be completed without jeopardizing the species or 
adversely modifying critical habitat. We intend to continue working 
with our Federal partners to provide technical assistance, 
coordination, and, in some instances, section 7 consultation. We do not 
anticipate that the listing of these species or the designation of 
critical habitat for the Pecos assiminea will preclude projects such as 
riparian restoration, fire prevention/management, or oil and gas 
development activities.
    Similarly, actions on private lands that have the potential to 
result in take of any of the four invertebrate species would be subject 
to section 10 of the Act, which requires development of a Habitat 
Conservation Plan as part of an application to the Service for an 
incidental take permit. These incidental take permits are issued 
pursuant to section 10(a)(1)(B) of the Act. Critical habitat has 
possible effects on activities conducted by non-Federal entities only 
if they are conducting activities on Federal lands or that involves 
Federal funding, a Federal permit, or other Federal action (e.g., 
grazing permits).
    Regulations at 50 CFR 424.02(j) define special management 
considerations or protection to mean any methods or procedures useful 
in protecting the physical and biological features of the environment 
for the conservation of listed species. When we designate critical 
habitat, we may not have the information necessary to identify all 
areas that are essential for the conservation of the species. 
Nevertheless, we are required to designate those areas we consider to 
be essential, using the best information available to us. Accordingly, 
we do not designate critical habitat in areas outside the geographical 
area occupied by the species unless the best available scientific and 
commercial data demonstrate that unoccupied areas are essential for the 
conservation needs of the species.
    The Service's Policy on Information Standards Under the Act, 
published in the Federal Register on July 1, 1994 (59 FR 34271), and 
Section 515 of the Treasury and General Government Appropriations Act 
for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658) and the associated 
Information Quality Guidelines issued by the Service, provide criteria, 
establish procedures, and provide guidance to ensure that decisions we 
make represent the best scientific and commercial data available. They 
require our biologists, to the extent consistent with the Act and with 
the use of the best scientific and commercial data available, to use 
primary and original sources of information as the basis for 
recommendations to designate critical habitat. When determining which 
areas are critical habitat, information may be obtained from the 
listing package, recovery plans, articles in peer-reviewed journals, 
conservation plans developed by States and counties or other entities 
that develop HCPs, scientific status surveys and studies, and 
biological assessments. In the absence of published data, unpublished 
materials and expert opinion or personal knowledge are used.
    Areas that support populations, but are outside the critical 
habitat designation, are still important to the species. Because of 
that they will continue to be subject to conservation actions 
implemented under section 7(a)(1) of the Act and to the regulatory 
protections afforded by the section 7(a)(2) jeopardy standard, as 
determined on the basis of the best available information at the time 
of the action. Federally funded or permitted projects affecting listed 
species outside their designated critical habitat areas may still 
result in jeopardy findings in some cases. Similarly, critical habitat 
designations made on the basis of the best available information at the 
time of designation will not control the direction and substance of 
future recovery plans, habitat conservation plans, or other species 
conservation planning efforts if new information available to these 
planning efforts calls for different approaches.
    In our critical habitat designation we use the provisions outlined 
in section 3(5)(A) of the Act to evaluate those specific areas defined 
by the features essential to the conservation of the species that may 
require special management considerations or protections. On the basis 
of our evaluation, we have determined that BLNWR does not require 
special management considerations or protections, and have excluded 
this area from the designation of critical habitat for these four 
invertebrates pursuant to section 3(5)(A) of the Act as discussed below 
(see ``Exclusions Under Section 3(5)(A) of the Act'' section below). 
Because the Roswell springsnail, Koster's springsnail, and Noel's 
amphipod are only found within or adjacent to the BLNWR, we are not 
designating critical habitat for these three species. The critical 
habitat discussion below only concerns habitat for the Pecos assiminea.

Primary Constituent Elements

    In accordance with section 3(5)(A)(i) of the Act and regulations at 
50 CFR 424.12, in determining which areas to propose as critical 
habitat, we consider those physical and biological features (primary 
constituent elements) that are essential to the conservation of the 
species and that may require special management considerations or 
protection. These features include but are not limited to: space for 
individual and population growth and for normal behavior; food, water, 
air, light,

[[Page 46322]]

minerals or other nutritional or physiological requirements; cover or 
shelter; sites for germination or seed dispersal; and habitats that are 
protected from disturbance or are representative of the historical, 
geographical, and ecological distributions of a species.
    This critical habitat designation does not include lands on BLNWR, 
New Mexico (see Exclusions Under Section 3(5)(A)'' and ``Summary of 
Changes to Proposed Rule'' sections). We determined the primary 
constituent elements for the Pecos assiminea (the only species which 
occurs off of BLNWR) from data and studies on its general habitat and 
life history requirements including, but not limited to: Taylor 1987; 
and NMDGF 1996, 1998, 1999, 2005b, and 2005c. A description of the 
essential environment as it relates to the specific primary constituent 
elements required of the Pecos assiminea is described below.

Space for Individual and Population Growth and Normal Behavior

    The Pecos assiminea requires saturated, moist soil at stream or 
spring run margins. Spring complexes that contain flowing water create 
saturated soils that provide the specific habitat needed for population 
growth, sheltering, and normal behavior of the species. This snail 
typically occurs near the soil surface or beneath leaf litter or 
vegetation in these areas (NMDGF 2005b). Consequently, wetland plant 
species are required to provide the leaf litter, shade, and appropriate 
microhabitat. Plant species such as American three-square (Scirpus 
americanus), spike rush (Eleocharis spp), inland saltgrass (Distichlis 
spicata) and rushes (Juncus spp.) provide the appropriate cover and 
shelter required Pecos assiminea (NMDGF 2005b).


    The Pecos assiminea is found in wet mud or beneath mats of 
vegetation, usually within a few centimeters (inches) of flowing water. 
The moist soil environment provides foraging and sheltering habitat, as 
well as habitat structure necessary for reproduction and successful 
recruitment of offspring. These areas provide the algae, bacteria, and 
decaying organic matter on which this species depends as a food 
resource. The Pecos assiminea is rarely found immersed in water or in 
standing water. Therefore, impoundment of springbrooks or streams is 
seen as detrimental to the survival of the species. It also does not 
appear to persist in areas with fluctuating water levels or in wetlands 
that freeze (Lang 2000). However, water is essential to the 
conservation of the Pecos assiminea because the species cannot 
withstand permanent drying (loss of surface flow) of springs or spring 
complexes. When water quality conditions degrade (e.g., water 
temperatures are too high, and dissolved oxygen concentrations are too 
low), Pecos assiminea will likely be injured or die.

Reproduction and Rearing of Offspring

    Little is known about the reproductive requirements for the Pecos 
assiminea. The native wetland plant community was included in this 
designation because the Pecos assiminea is found within the moist 
environment directly adjacent to the aquatic habitat. Substrates found 
in these margin areas provide for temperatures within the environmental 
tolerance for this species, and the habitat for reproduction that the 
Pecos assiminea requires.


    The Pecos assiminea has a file-like radula (a ribbon of teeth) 
situated behind the mouth that is used to graze or scrape food from the 
foraging surface. Saturated soils and wetland vegetation adjacent to 
spring complexes contribute to the necessary components to support the 
algae, detritus, and bacteria on which this species forages.
    The discussion above describes the physical and biological features 
essential to the Pecos assiminea and presents our rationale as to why 
the features identified below were selected. The primary constituent 
elements described below include the essential features of spring 
complexes that develop, maintain, and regenerate the habitat components 
required for the Pecos assiminea to forage, reproduce, and shelter. The 
specific biological and physical features, otherwise referred to as the 
primary constituent elements, essential to the conservation of the 
Pecos assiminea are:
    (1) Permanent, flowing, unpolluted, fresh to moderately saline 
    (2) Moist or saturated soil at stream or spring run margins with 
native vegetation growing in or adapted to aquatic or very wet 
environment, such as salt grass or sedges; and
    (3) Stable water levels with natural diurnal and seasonal 

Criteria for Defining Critical Habitat

    Restoring an endangered or threatened species to the point where it 
is recovered is a primary goal of our Endangered Species Program. To 
help guide the recovery effort, we are required to prepare and 
implement recovery plans for all of the listed species native to the 
United States unless such plan will not promote the conservation of the 
species and the species is therefore exempt from having a plan 
developed for it. Recovery plans describe actions considered necessary 
for conservation of the species, establish criteria for downlisting or 
delisting them, and estimate time and cost for implementing the 
recovery measures needed. A final recovery plan formalizes the recovery 
strategy for a species, but is not a regulatory document (i.e., 
recovery plans are advisory documents because there are no specific 
protections, prohibitions, or requirements afforded to a species based 
solely on a recovery plan). Critical habitat contributes to the overall 
recovery strategy for listed species, but does not by itself achieve 
recovery plan goals.
    We do not currently have a recovery plan for Pecos assiminea. 
Nevertheless, we have reviewed the recovery plan developed by the State 
of New Mexico (NMDGF 2005b). In designating critical habitat for the 
Pecos assiminea, we also reviewed information within our files and 
recommendations contained in State wildlife resource reports (Balleau 
et al. 1999; NMDGF 2005a, 2005b, 1999, 1998, Boghici 1997; Jones and 
Balleau 1996; and Cole 1985). We also reviewed the available literature 
pertaining to habitat requirements, historic localities, and current 
localities for this species.
    We are not aware of any reliable information that is currently 
available to us that was not considered in this designation process. 
This final determination constitutes our best assessment of areas 
needed for the conservation of the species. Much remains to be learned 
about this species; should credible new information become available 
which contradicts this designation, we will reevaluate our analysis 
and, if appropriate, propose to modify this critical habitat 
designation, depending on available funding and staffing. We must make 
this determination on the basis of the information available at this 
time, and we may not delay our decision until more information about 
the species and its habitat are available (Southwest Center for 
Biological Diversity v. Babbitt, 215 F.3d 58 (D.C. Cir. 2000)).
    The designated critical habitat constitutes our best assessment of 
the specific areas that contain the primary constituent elements for 
Pecos assiminea and that may require special management or protection. 
The designated areas are within the geographical area occupied by Pecos 
assiminea populations and currently have one or more constituent 

[[Page 46323]]

(see description of primary constituent elements, above).

Critical Habitat Designation

    We designate two units as critical habitat for the Pecos assiminea 
(see the ``Regulation Promulgation'' section of this final rule for 
exact boundary descriptions). These critical habitat units include 
primary constituent elements that provide for the physiological, 
behavioral, and ecological requirements essential for the conservation 
of Pecos assiminea. The designation includes one complex at Diamond Y 
Spring and a segment of the drainage and East Sandia Spring. Critical 
habitat units are designated in portions of Pecos and Reeves Counties, 
Texas. Detailed digital files of each unit can be obtained by 
contacting the New Mexico Ecological Services Field Office (see 
ADDRESSES section).
    A general description of land ownership in both areas follows:
    1. Diamond Y Springs Complex, Pecos County, Texas. This area 
comprises a major population of Pecos assiminea. The designation 
includes the Diamond Y Spring and approximately 6.8 km (4.2 mi) of its 
outflow, ending at approximately 0.8 km (0.5 mi) downstream of the 
State Highway 18 bridge crossing. Also included is approximately 0.8 km 
(0.5 mi) of Leon Creek upstream of the confluence with Diamond Y Draw. 
All surrounding riparian vegetation and mesic soil environments within 
the spring, outflow, and portion of Leon Creek are also designated as 
these areas are considered habitat for the Pecos assiminea. This 
designation is approximately 153.8 ha (380 ac) of aquatic and 
neighboring mesic habitat. This complex occurs entirely on private 
lands. Private land in the immediate vicinity of the Diamond Y Springs 
Complex is managed as a nature preserve by TNC.
    2. East Sandia Spring, Reeves County, Texas. This spring contains a 
population of Pecos assiminea. The designation includes the springhead 
itself, surrounding seeps, and all submergent vegetation and moist soil 
habitat found at the margins of these areas. These areas are considered 
habitat for the Pecos assiminea. This designation is approximately 6.7 
ha (16.5 ac) of aquatic and neighboring upland habitat. The site is 
private land managed as a nature preserve by TNC.

Exclusions Under Section 3(5)(A) of the Act

    As we undertake the process of designating critical habitat for a 
species, we first evaluate lands defined by those physical and 
biological features essential to the conservation of the species for 
inclusion in the designation pursuant to section 3(5)(A) of the Act. We 
then evaluate lands defined by those features to assess whether they 
may require special management considerations or protection. As 
discussed in the five factor analysis above, the Pecos assiminea is 
imperiled by a multitude of threats such as oil and gas operations, 
introduced species, groundwater contamination and depletion, drought, 
risk of wildfire, and inadequate regulatory mechanisms.
    Below we first provide some general background information on the 
BLNWR and the Comprehensive Conservation Plan (CCP), followed by an 
analysis pursuant to section 3(5)(A) of the Act of the current 
management provisions on BLNWR, and an analysis of why we believe 
special management is not required. Pursuant to section 3(5)(A)(i) of 
the Act, we consider the areas that we are excluding on the BLNWR to be 
within the geographical range occupied by the four invertebrate 
species. As noted in the environmental assessment, one of the areas on 
the BLNWR, the impoundment complex, contains an area that could allow 
for future expansion of existing populations. While this area is not 
known to be currently occupied, we consider it to be within the 
geographical range occupied by the four invertebrate species because it 
is in close proximity to known occupied areas (i.e., ranging from 
approximately 164 to 656 feet (50 to 200 m)), and it would be an area 
where section 7 consultations would occur because of the potential 
presence of the four invertebrate species and known proximity to 
occupied areas.
    The BLNWR was established on October 8, 1937, by Executive Order 
7724 ``as a refuge and breeding ground for migratory birds and other 
wildlife.'' The Refuge Recreation Act (16 U.S.C. 460-1) identifies the 
refuge as being ``suitable for incidental fish and wildlife-oriented 
recreational development, the protection of natural resources, and the 
conservation of endangered species or threatened species.'' The 
Wilderness Act of 1964 (Pub. L. 88-577) directs the Service to 
``maintain wilderness as a naturally functioning ecosystem'' on 
portions of the Refuge. While the BLNWR was originally established to 
save wetlands vital to the perpetuation of migratory birds, the 
isolated gypsum springs, seeps, and associated wetlands protected by 
the Refuge have been recognized as providing the last known habitats in 
the world for several unique species. Management emphasis of the BLNWR 
is placed on the protection and enhancement of habitat for endangered 
species and Federal candidate species, maintenance and improvement of 
wintering crane and waterfowl habitat, and monitoring and maintenance 
of natural ecosystem values.
    The BLNWR sits at a juncture between the Roswell Artesian 
Groundwater Basin and the Pecos River. These two systems and their 
interactions account for the diversity of water resources on the 
Refuge, including sinkholes, springs, wetlands, oxbow lakes, and 
riverine habitats. The BLNWR has a federally reserved water right that 
essentially protects groundwater levels of the Roswell Basin in the 
Refuge vicinity. The Refuge has undergone adjudication of its federally 
reserved water rights by the State of New Mexico (order signed May 
1997). The BLNWR is currently in negotiations with the New Mexico 
Interstate Stream Commission, a State agency responsible for 
administering New Mexico's water resources, to quantify these reserved 
rights (Service 2005).
    The National Wildlife Refuge System Improvement Act of 1997 
establishes a conservation mission for refuges, gives policy direction 
to the Secretary of the Interior and refuge managers, and contains 
other provisions such as the requirement to integrate scientific 
principals into the management of the Refuges. According to Section 
7(e)(1)(E) of the Refuge Improvement Act, all lands of the Refuge 
System are to be managed in accordance with an approved CCP that will 
guide management decisions and set forth strategies for achieving 
refuge purposes. In general, the purpose of the CCP is to provide long-
range guidance for the management of National Wildlife Refuges. The 
Refuge Improvement Act requires all refuges to have a CCP and provides 
the following legislative mandates to guide the development of the CCP: 
(1) Wildlife has first priority in the management of refuges; (2) 
wildlife-dependent recreation including hunting, fishing, wildlife 
observation, wildlife photography, environmental education and 
environmental interpretation are the priority public uses of the refuge 
system, and shall be allowed when compatible with the refuge purpose; 
and (3) other uses have lower priority in the refuge system and are 
only allowed if not in conflict with any of the priority uses and 
determined appropriate and compatible with the refuge purpose.
    The CCP must also be revised if the Secretary determines that 
conditions that affect the refuge or planning unit have changed 
significantly. In other words, a CCP must be followed once it

[[Page 46324]]

is approved, and regularly updated in response to environmental changes 
or new scientific information.
    The BLNWR has a Final CCP that was approved in September 1998. The 
CCP serves as a management tool to be used by the Refuge staff and its 
partners in the preservation and restoration of the ecosystem's natural 
resources. The plan is intended to guide management decisions over the 
next 5 to 10 years and sets forth strategies for achieving Refuge goals 
and objectives within that timeframe. Key goals of the CCP related to 
these four invertebrates include the following: (1) To restore, enhance 
and protect the natural diversity on the BLNWR including threatened and 
endangered species by (a) appropriate management of habitat and 
wildlife resources on refuge lands and (b) by strengthening existing 
and establishing new cooperative efforts with public and private 
stakeholders and partners, and (2) To restore and maintain selected 
portions of a hydrological system that more closely mimics the natural 
processes along the reach of the Pecos River adjacent to the BLNWR by: 
(a) restoration of the river channel, as well as restoration of 
threatened, endangered, and special concern species; and (b) control of 
exotic species and manage trust responsibilities for maintenance of 
plant and animal communities and to satisfy traditional recreational 
demands. Specific objectives related to these goals include: (1) The 
restoration of populations of aquatic species designated as endangered, 
threatened, or of special concern to a sustainable level (aquatic 
species in these categories include the four invertebrates), and (2) 
the monitoring of wildlife populations, including endemic snails.
    As explained in detail above, we believe that BLNWR lands are 
already managed for the conservation of wildlife and special management 
considerations or protections are not required. Therefore, these lands 
do not meet the definition of critical habitat, and we are not 
designating critical habitat for the four invertebrate species within 
    Critical habitat receives protection from destruction or adverse 
modification through required consultation under section 7 of the Act. 
The section 7 consultation process is triggered when a Federal agency 
determines that its proposed Federal action (i.e., an action that it 
funds, carries out, or authorizes) may affect a listed species or its 
critical habitat. Thus, the principal benefit of any designated 
critical habitat is that Federal activities that may affect critical 
habitat require consultation under section 7 of the Act.
    Once consultation under section 7 of the Act is triggered, the 
process may conclude informally when the Service concurs in writing 
that the proposed Federal action is not likely to adversely affect the 
listed species or its critical habitat. However, if the Service 
determines through informal consultation that adverse impacts are 
likely to occur, then formal consultation is initiated. Formal 
consultation concludes with a biological opinion issued by the Service 
on whether the proposed Federal action is likely to jeopardize the 
continued existence of a listed species or result in destruction or 
adverse modification of critical habitat, with separate analyses being 
made under both the jeopardy and the adverse modification standards. 
For critical habitat, a biological opinion that concludes in a 
determination of no destruction or adverse modification may contain 
discretionary conservation recommendations to minimize adverse effects 
to primary constituent elements, but it would not contain any mandatory 
reasonable and prudent measures or terms and conditions. Mandatory 
reasonable and prudent alternatives to the proposed Federal action 
would only be issued when the biological opinion results in a jeopardy 
or adverse modification conclusion.
    The designation of critical habitat does not imply that lands 
outside of critical habitat do not play an important role in the 
conservation of these four invertebrate species. Federal activities 
that may affect those unprotected areas (such as groundwater pumping, 
oil and gas activities, and livestock grazing, etc.) outside of 
critical habitat are still subject to review under section 7 of the Act 
if they may affect these species. The prohibitions of section 9 of the 
Act (e.g., harm, harass, capture) also continue to apply both inside 
and outside of designated critical habitat.

Effect of Critical Habitat Designation

Section 7 Consultation

    Section 7(a)(2) of the Act requires Federal agencies, including us, 
to insure that their actions are not likely to jeopardize the continued 
existence of a listed species or result in the destruction or adverse 
modification of designated critical habitat. This requirement is met 
through section 7 consultation under the Act. Our regulations define 
``jeopardize the continued existence of'' as to engage in an action 
that reasonably would be expected, directly or indirectly, to reduce 
appreciably the likelihood of both the survival and recovery of a 
listed species in the wild by reducing the reproduction, numbers, or 
distribution of that species (50 CFR 402.02). ``Destruction or adverse 
modification of designated critical habitat'' for this species would 
include habitat alterations that appreciably diminish the value of 
critical habitat by significantly affecting any of those physical or 
biological features that were the basis for determining the habitat to 
be critical. We are currently reviewing the regulatory definition of 
adverse modification in relation to the conservation of the species.
    If we issue a biological opinion concluding that a project is 
likely to result in the destruction or adverse modification of critical 
habitat, we also provide ``reasonable and prudent alternatives'' to the 
project, if any are identifiable. Reasonable and prudent alternatives 
are defined at 50 CFR 402.02 as alternative actions identified during 
consultation that can be implemented in a manner consistent with the 
intended purpose of the action, that are consistent with the scope of 
the Federal agency's legal authority and jurisdiction, that are 
economically and technologically feasible, and that the Service's 
Regional Director believes would avoid the likelihood of jeopardizing 
the continued existence of listed species or resulting in the 
destruction or adverse modification of critical habitat. Reasonable and 
prudent alternatives can vary from slight project modifications to 
extensive redesign or relocation of the project. Costs associated with 
implementing a reasonable and prudent alternative are similarly 
    Activities on Federal lands that may affect the four invertebrates 
or their habitat will require consultation pursuant to section 7 of the 
Act. Activities on State or private lands requiring a permit from a 
Federal agency, such as a permit from the U.S. Army Corps of Engineers, 
or some other Federal action, including funding, will continue to be 
subject to the section 7 consultation process. Federal actions not 
affecting listed species or critical habitat, and actions on non-
Federal lands that are not federally funded, authorized, or permitted, 
do not require section 7 consultations.
    Section 4(b)(8) of the Act requires us to evaluate briefly and 
describe, in any proposed or final regulation that designates critical 
habitat, those activities involving a Federal action that may adversely 
modify such habitat or that may be affected by such designation. 
Activities that may destroy or adversely modify critical habitat

[[Page 46325]]

include those that alter the primary constituent elements to an extent 
that the value of critical habitat for both the survival and recovery 
of the Pecos assiminea is appreciably reduced. We note that such 
activities may also jeopardize the continued existence of the species. 
Activities that, when carried out, funded, or authorized by a Federal 
agency that may affect the Pecos assiminea and may require consultation 
under section 7 of the Act to determine if they adversely modify 
critical habitat include, but are not limited to:
    (1) Any activity that would significantly alter the source-water 
capture zone, subterranean flows, or water level of the supporting 
aquifers (groundwater pumping), including any activity that would 
significantly alter the water chemistry, water quality, or physical 
parameters (e.g., temperature, pH, contaminants), or wastewater or 
point-source discharge permits in the wetland habitats and systems that 
could appreciably diminish the primary constituent elements where this 
species occurs;
    (2) Any activity that would introduce, spread, or augment non-
native aquatic predators or competitors, or non-native species that 
negatively alter Pecos assiminea habitat or primary constituent 
elements: this would include the introduction of non-native species 
through contaminated sampling gear, bait-bucket introductions of non-
native fishes, or the release of aquarium species (fish, aquatic 
snails, and aquatic plants) from uninformed members of the public; or
    (3) Any activity that would detrimentally alter the habitat for 
Pecos assiminea. This would include water diversion, drainage 
alteration projects, road construction, construction of public and 
private facilities, or ponding of spring runs.
    Specific examples of Federal activities include, but are not 
limited to, EPA authorization of discharges under the National 
Pollutant Discharge Elimination System and registration of pesticides; 
Federal Highway Administration approval or funding of road or highway 
infrastructure and maintenance; BLM issuance of oil and gas leases or 
permits; U.S. Army Corps of Engineers authorization of discharges of 
dredged or fill material into waters of the United States under section 
404 of the Clean Water Act; USDA-Natural Resources Conservation Service 
technical assistance and other programs; USDA-Rural Utilities Service 
infrastructure or development; Federal Energy Regulatory Commission 
permitting activities; and the Department of Housing and Urban 
Development's Small Cities Community Development Block Grant and home 
loan programs.

Available Conservation Measures

    Conservation measures provided to species listed as endangered or 
threatened under the Act include recognition, recovery actions, 
requirements for Federal protection, and prohibitions against certain 
practices. Recognition through listing encourages and results in 
conservation actions by Federal, State, and private agencies, groups, 
and individuals. The Act provides for possible land acquisition and 
cooperation with the States and authorizes recovery plans for all 
listed species. The protection required of Federal agencies and the 
prohibitions against certain activities involving listed animals are 
discussed in the ``Effect of Critical Habitat Designation'' section 
    Section 7(a) of the Act, as amended, requires Federal agencies to 
evaluate their actions with respect to any species that is proposed to 
be listed or is listed as endangered or threatened, and with respect to 
its critical habitat, if any is being designated. Regulations 
implementing this interagency cooperation provision of the Act are 
codified at 50 CFR part 402. Federal agencies are required to confer 
with us informally on any action that is likely to jeopardize the 
continued existence of a proposed species, or result in destruction or 
adverse modification of proposed critical habitat. If a species is 
listed subsequently, section 7(a)(2) requires Federal agencies to 
ensure that activities they authorize, fund, or carry out are not 
likely to jeopardize the continued existence of such a species or to 
destroy or adversely modify its critical habitat. If a Federal agency 
action may affect a listed species or its critical habitat, the 
responsible Federal agency must enter into formal consultation with us. 
Federal agency actions that may affect the four invertebrates 
throughout their range and may require consultation with us include, 
but are not limited to, oil and gas development, irrigated agricultural 
and livestock activities, residential and commercial development, non-
native vegetation control, fire suppression, controlled burns, water 
control structures, and habitat enhancement projects.
    Listing the four invertebrates provides for the development and 
implementation of a rangewide recovery plan. This plan will bring 
together Federal, State, and local agency efforts for the conservation 
of these species. A recovery plan will establish a framework for 
agencies to coordinate their recovery efforts. The plan will set 
recovery priorities and estimate the costs of the tasks necessary to 
accomplish the priorities. It also will describe the site-specific 
actions necessary to achieve conservation and survival of the species.
    Listing also will require us to review any actions that may affect 
the four invertebrates for lands and activities under Federal 
jurisdiction, State plans developed pursuant to section 6 of the Act, 
scientific investigations of efforts to enhance the propagation or 
survival of the animal pursuant to section 10(a)(1)(A) of the Act, and 
habitat conservation plans prepared for non-Federal lands and 
activities pursuant to section 10(a)(1)(B) of the Act.
    Federal agencies with management responsibility for the four 
invertebrates include the Service, in relation to the issuance of 
section 10(a)(1)(A) and (B) permits for scientific research, habitat 
conservation plans, BLNWR management and maintenance, and other 
    The Act and implementing regulations found at 50 CFR 17.21 set 
forth a series of general prohibitions and exceptions that apply to all 
endangered wildlife. These prohibitions, in part, make it illegal for 
any person subject to the jurisdiction of the United States to take 
(includes harass, harm, pursue, hunt, shoot, wound, kill, trap, or 
collect, or to attempt any of these), import or export, ship in 
interstate commerce in the course of commercial activity, or sell or 
offer for sale in interstate or foreign commerce any listed species. It 
also is illegal to possess, sell, deliver, carry, transport, or ship 
any such wildlife that has been taken illegally. Certain exceptions 
apply to agents of the U.S. Fish and Wildlife Service and State 
conservation agencies.
    Permits may be issued to carry out otherwise prohibited activities 
involving endangered wildlife species under certain circumstances. 
Regulations governing permits are at 50 CFR 17.22 and 17.23. Such 
permits are available for scientific purposes, to enhance the 
propagation or survival of the species, or for incidental take in the 
course of otherwise lawful activities.
    Pursuant to the Interagency Cooperative Policy for Endangered 
Species Act Section 9 Prohibitions, published in the Federal Register 
on July 1, 1994 (59 FR 34272), we identify to the maximum extent 
practicable those activities that would or would not constitute a 
violation of section 9 of the Act. The intent of this policy is to 
increase public awareness as to the effects of this listing on future 

[[Page 46326]]

ongoing activities within the species' range. We believe, based on the 
best available information that the following actions will not result 
in a violation of the provisions of section 9 of the Act, provided 
these actions are carried out in accordance with existing regulations 
and permit requirements:
    (1) Possession, delivery, or movement, including interstate 
transport that does not involve commercial activity, of specimens of 
these species that were legally acquired prior to the publication in 
the Federal Register of the Federal List of Endangered and Threatened 
Wildlife and Plants;
    (2) Oil and gas exploration and drilling in areas where surface or 
groundwater is not connected to habitats occupied by the Roswell 
springsnail, Koster's springsnail, Pecos assiminea, and Noel's 
amphipod; and
    (3) Any actions that may affect the Roswell springsnail, Koster's 
springsnail, Noel's amphipod, and Pecos assiminea that are authorized, 
funded, or carried out by a Federal agency (e.g., prescribed burns, 
pesticide/herbicide application, pipeline construction crossing 
suitable habitat, oil and gas development or extraction activities), 
when the action is conducted in accordance with the consultation 
requirements for listed species pursuant to section 7 of the Act.
    Potential activities involving these species that we believe will 
likely be considered a violation of section 9 include, but are not 
limited to, the following:
    (1) Unauthorized possession, collecting, trapping, capturing, 
killing, harassing, sale, delivery, or movement, including interstate, 
and foreign commerce, or harming, or attempting any of these actions, 
of the Roswell springsnail, Koster's springsnail, Noel's amphipod, and 
Pecos assiminea. Research activities where these species are trapped or 
captured will require a permit under section 10(a)(1)(A) of the Act;
    (2) The use of chemical insecticides or herbicides that results in 
killing or injuring these species;
    (3) Intentional release of exotic species (including, but not 
limited to, mosquitofish, crayfish, or non-native snails) into habitat 
currently occupied by the Roswell springsnail, Koster's springsnail, 
Noel's amphipod, and Pecos assiminea;
    (4) Within the 12,585 ac (5,093 ha) of the Federal mineral estate 
and 9,945 ac (4,025 ha) habitat protection zone in New Mexico (e.g., 
BLM 2002, Balleau et al. 1999), subsurface drilling or similar 
activities that contaminate or cause significant degradation of surface 
drainage water or aquifer water quality that supports the habitat 
occupied by these species;
    (5) Septic tank placement and use where the groundwater is 
connected to sinkhole or other aquatic habitats occupied by these 
    (6) Unauthorized discharges or dumping of toxic chemicals, silt, or 
other pollutants into, or other illegal alteration of the areas 
supporting Roswell springsnail, Koster's springsnail, Noel's amphipod, 
and Pecos assiminea that results in death or injury of the species or 
that results in degradation of their occupied habitat to an extent that 
individuals are killed or injured or essential behaviors such as 
breeding, feeding, and sheltering are impaired; and
    (7) Destruction or alteration of the Roswell springsnail, Koster's 
springsnail, Noel's amphipod, and Pecos assiminea occupied habitat 
through discharge of fill materials into occupied sites; draining, 
ditching, tilling, channelization, drilling, pumping, or other 
activities that interrupt surface or ground water flow into or out of 
the spring complexes, and occupied habitats of these species that 
results in killing or injuring these species by significantly impairing 
essential life-sustaining requirements such as breeding, feeding, and 
    If you have questions regarding whether specific activities will 
likely violate the provisions of section 9 of the Act, contact the New 
Mexico Ecological Services Field Office (see ADDRESSES section). For 
Pecos assiminea in Texas, contact the Austin Ecological Services Field 
Office, 10711 Burnet Road, Suite 200, Austin, Texas 78758 (512/490-
0057). Requests for copies of the regulations on listed wildlife and 
inquiries about prohibitions and permits may be addressed to the U.S. 
Fish and Wildlife Service, Division of Endangered Species, P.O. Box 
1306, Albuquerque, New Mexico 87103 (telephone 505/248-6920; facsimile 

Economic Analysis

    Section 4(b)(2) of the Act requires us to designate critical 
habitat on the basis of the best scientific and commercial data 
available and to consider the economic impact, impact to national 
security, and other relevant impacts of designating a particular area 
as critical habitat. We based this designation on the best available 
scientific information. We utilized the economic analysis, and took 
into consideration comments and information submitted during the public 
hearing and comment periods to make this final listing and critical 
habitat determination. We may exclude areas from critical habitat upon 
a determination that the benefits of such exclusions outweigh the 
benefits of specifying such areas as critical habitat. We cannot 
exclude such areas from critical habitat when such exclusion will 
result in the extinction of the species.
    A draft analysis of the economic effects of the proposed critical 
habitat designation was prepared and made available for public review 
(70 FR 23083; May 4, 2005). The economic analysis considers the 
economic impacts of conservation measures taken prior to and subsequent 
to the final listing and designation of critical habitat for the four 
invertebrates. Pre-designation impacts are typically defined as all 
management efforts that have occurred since the time of listing. The 
four invertebrates have not been listed, but were proposed for listing 
in February 2002 (67 FR 6459). Total post-designation costs associated 
with proposed critical habitat Units 3 and 4 for the Pecos assiminea on 
TNC lands in Texas are estimated to be $707,000 over the next 20 years 
(Service 2005a). Estimated costs include creating a conservation plan 
to formally assess conservation elements and future management actions 
within proposed critical habitat Units 3 and 4. Additionally, future 
costs to oil and gas activities within proposed Unit 3 are anticipated 
to be related to continued partnership projects between TNC and 
regional oil and gas companies.
    Based upon these estimates, we conclude in the final analysis, 
which reviewed and incorporated public comments, that no significant 
economic impacts (i.e., will not have annual effect on the economy of 
$100 million or more or affect the economy in a material way discussed 
further in the ``Required Determinations'' section below) are expected 
from the designation of critical habitat for Pecos assiminea. A copy of 
the economic analysis is included in our supporting record and may be 
obtained by contacting the New Mexico Ecological Services Field Office 
(see ADDRESSES section) or from our Web site http://ifw2es.fws.gov/.

Required Determinations

Regulatory Planning and Review

    In accordance with Executive Order 12866, this document is a 
significant rule because it may raise novel legal and policy issues. 
However, based on our final economic analysis, it is not anticipated 
that the designation of critical habitat for the four invertebrate 
species will result in an annual effect on

[[Page 46327]]

the economy of $100 million or more or affect the economy in a material 
way. Due to the timeline for publication in the Federal Register, the 
Office of Management and Budget (OMB) has not formally reviewed the 
final rule or accompanying economic analysis.
    Further, Executive Order 12866 directs Federal Agencies 
promulgating regulations to evaluate regulatory alternatives (Office of 
Management and Budget, Circular A-4, September 17, 2003). Pursuant to 
Circular A-4, once it has been determined that the Federal regulatory 
action is appropriate, then the agency will need to consider 
alternative regulatory approaches. Since the determination of critical 
habitat is a statutory requirement pursuant to the Endangered Species 
Act of 1973, as amended (Act) (16 U.S.C. 1531 et seq.), we must then 
evaluate alternative regulatory approaches, where feasible, when 
promulgating a designation of critical habitat.
    In developing our designations of critical habitat, we consider 
economic impacts, impacts to national security, and other relevant 
impacts pursuant to section 4(b)(2) of the Act. Based on the discretion 
allowable under this provision, we may exclude any particular area from 
the designation of critical habitat providing that the benefits of such 
exclusion outweighs the benefits of specifying the area as critical 
habitat and that such exclusion would not result in the extinction of 
the species. As such, we believe that the evaluation of the inclusion 
or exclusion of particular areas, or combination thereof, in a 
designation constitutes our regulatory alternative analysis.

Regulatory Flexibility Act (5 U.S.C. 601 et seq.)

    Under the Regulatory Flexibility Act, 5 U.S.C. 601 et seq., as 
amended by the Small Business Regulatory Enforcement Act, (SBREFA) 5 
U.S.C. 802 (2), whenever an agency is required to publish a notice of 
rulemaking for any proposed or final rule, it must prepare and make 
available for public comment a regulatory flexibility analysis that 
describes the effect of the rule on small entities (i.e., small 
businesses, small organizations, and small government jurisdictions). 
However, no regulatory flexibility analysis is required if the head of 
an agency certifies the rule will not have a significant economic 
impact on a substantial number of small entities. Our economic analysis 
of the proposed designation provides the factual basis for our 
    According to the Small Business Administration (SBA), small 
entities include small organizations, such as independent nonprofit 
organizations and small governmental jurisdictions, including school 
boards and city and town governments that serve fewer than 50,000 
residents, as well as small businesses (13 CFR 121.201). Small 
businesses include manufacturing and mining concerns with fewer than 
500 employees, wholesale trade entities with fewer than 100 employees, 
retail and service businesses with less than $5 million in annual 
sales, general and heavy construction businesses with less than $27.5 
million in annual business, special trade contractors doing less than 
$11.5 million in annual business, and agricultural businesses with 
annual sales less than $750,000. To determine if potential economic 
impacts to these small entities are significant, we considered the 
types of activities that might trigger regulatory impacts under this 
designation as well as types of project modifications that may result. 
In general, the term significant economic impact is meant to apply to a 
typical small business firm's business operations.
    Activities anticipated to occur within the next 20 years within or 
adjacent to critical habitat for the Pecos assiminea that potentially 
effect small businesses include: oil and gas production, irrigated 
agricultural production, and livestock operations.
    With regard to livestock operations the economic analysis finds 
that confined animal feeding facilities do not occur in Pecos or Reeves 
Counties, Texas, within 60 miles of the critical habitat designation. 
As such, the analysis does not anticipate impacts to small entities 
within the livestock industry in these counties.
    Agricultural production dependent on groundwater irrigation occurs 
within Pecos and Reeves Counties, Texas. The analysis assumes that all 
farms operating within the regions are small entities. Within Texas, 
further hydrological studies are necessary to determine the impact of 
groundwater pumping on surface and groundwater levels to designated 
critical habitat. As a result, groundwater withdrawal activities for 
agricultural production are unlikely to change as a result of the 
presence of the Pecos assiminea. Thus, no impacts to small entities 
within the irrigated agricultural industry are expected.
    Oil and gas drilling occurs on private lands outside of critical 
habitat Unit 3 (Diamond Y Springs Complex) in Texas. The economic 
analysis finds that while oil and gas activities may present water 
quality issues, they are not considered a threat to groundwater levels 
in the region. The analysis does not forecast modifications to oil and 
gas production in Texas and therefore no impacts to small businesses 
are quantified. This is due to the fact that Unit 3 is owned and 
managed by TNC. TNC manages this area as a preserve for long term 
habitat conservation and protection of the functional integrity of 
surface water systems to benefit rare aquatic species and communities 
within the preserves. TNC does not own the mineral rights at Unit 3. 
However, the companies that own or lease these rights have generally 
worked voluntarily with TNC to protect these lands. The economic 
analysis finds that future costs to oil and gas activities within Unit 
3 are anticipated to be related to continued partnership projects 
between TNC and regional oil and gas companies. There may also be a 
potential for costs associated with an incidental take permit and 
Habitat Conservation Plan under section 10 of the Act. However, the 
economic analysis finds that the potential for that occurrence is 
    There has been one section 7 consultation on an oil and gas project 
with Federal involvement in the vicinity of habitats occupied by the 
four invertebrates. This was an informal consultation in 2004 regarding 
proposed abandonment of 58 miles of pipeline in Winkler, Ward, Reeves, 
and Pecos counties, Texas (Service 2004b). The proposed project 
involved permitting by the Federal Energy Regulatory Commission. It was 
determined that the proposed action would not have any affect on any of 
the four invertebrate species or any co-occurring, listed, aquatic taxa 
such as Leon Springs pupfish. There were no conservation 
recommendations made by the Service regarding protection of aquatic 
habitats in this consultation. Based upon this and other information 
presented in the draft economic analysis and draft environmental 
assessment, we do not anticipate economic costs to small businesses in 
this industry. Therefore, we have considered whether this rule would 
result in a significant economic effect on a substantial number of 
small entities. We have concluded that this final designation of 
critical habitat for the Pecos assiminea would not affect a substantial 
number of small entities. Therefore, we are certifying that the 
designation of critical habitat for the Pecos assiminea will not have a 
significant economic impact on a substantial number of small entities, 
and a final regulatory flexibility analysis is not required.

Executive Order 13211

    On May 18, 2001, the President issued Executive Order (E.O.) 13211 

[[Page 46328]]

regulations that significantly affect energy supply, distribution, and 
use. E.O. 13211 requires agencies to prepare Statements of Energy 
Effects when undertaking certain actions. This final rule is considered 
a significant regulatory action under E.O. 12866 due to it potentially 
raising novel legal and policy issues, but the economic analysis finds 
that the oil and gas industry is not likely to experience ``a 
significant adverse effect'' as a result of conservation efforts for 
the four invertebrates. Appendix A of the draft economic analysis 
provides a detailed discussion and analysis of this determination. 
Specifically, two criteria were determined to be relevant to this 
analysis: (1) Reductions in natural gas production in excess of 25 
million mcf per year, and (2) increases in the cost of energy 
production in excess of one percent. Impacts to ongoing oil and gas 
production in Pecos County, Texas, are not forecast as it is unclear 
whether these activities will require conservation efforts for the 
Pecos assiminea. As described in Section 4.2.1 of the economic analysis 
and above, while oil and gas activities in this region may affect 
groundwater quality, they are not anticipated to affect groundwater 

Unfunded Mandates Reform Act (2 U.S.C. 1501 et seq.)

    In accordance with the Unfunded Mandates Reform Act (2 U.S.C. 
1501), the Service makes the following findings:
    (a) This rule will not produce a Federal mandate. In general, a 
Federal mandate is a provision in legislation, statute or regulation 
that would impose an enforceable duty upon State, local, or Tribal 
governments, or the private sector and includes both ``Federal 
intergovernmental mandates'' and ``Federal private sector mandates.'' 
These terms are defined in 2 U.S.C. 658(5)-(7). ``Federal 
intergovernmental mandate'' includes a regulation that ``would impose 
an enforceable duty upon State, local, or Tribal governments'' with two 
exceptions. It excludes ``a condition of Federal assistance.'' It also 
excludes ``a duty arising from participation in a voluntary Federal 
program,'' unless the regulation ``relates to a then-existing Federal 
program under which $500,000,000 or more is provided annually to State, 
local, and Tribal governments under entitlement authority,'' if the 
provision would ``increase the stringency of conditions of assistance'' 
or ``place caps upon, or otherwise decrease, the Federal Government's 
responsibility to provide funding'' and the State, local, or Tribal 
governments ``lack authority'' to adjust accordingly. (At the time of 
enactment, these entitlement programs were: Medicaid; AFDC work 
programs; Child Nutrition; Food Stamps; Social Services Block Grants; 
Vocational Rehabilitation State Grants; Foster Care, Adoption 
Assistance, and Independent Living; Family Support Welfare Services; 
and Child Support Enforcement.) ``Federal private sector mandate'' 
includes a regulation that ``would impose an enforceable duty upon the 
private sector, except (i) a condition of Federal assistance; or (ii) a 
duty arising from participation in a voluntary Federal program.''
    The designation of critical habitat does not impose a legally 
binding duty on non-Federal government entities or private parties. 
Under the Act, the only regulatory effect is that Federal agencies must 
ensure that their actions do not destroy or adversely modify critical 
habitat under section 7. While non-Federal entities who receive Federal 
funding, assistance, permits or otherwise require approval or 
authorization from a Federal agency for an action may be indirectly 
impacted by the designation of critical habitat, the legally binding 
duty to avoid destruction or adverse modification of critical habitat 
rests squarely on the Federal agency. Furthermore, to the extent that 
non-Federal entities are indirectly impacted because they receive 
Federal assistance or participate in a voluntary Federal aid program, 
the Unfunded Mandates Reform Act would not apply; nor would critical 
habitat shift the costs of the large entitlement programs listed above 
on to State governments.
    (b) We do not believe that this rule will significantly or uniquely 
affect small governments. This determination is based on information 
from the economic analysis conducted for this designation of critical 
habitat for the Pecos assiminea and the fact that critical habitat is 
only being designated on TNC lands. As such, a Small Government Agency 
Plan is not required.


    In accordance with Executive Order 12630 (``Government Actions and 
Interference with Constitutionally Protected Private Property 
Rights''), we have analyzed the potential takings implications of 
proposing critical habitat for the Pecos assiminea in a takings 
implications assessment. The takings implications assessment concludes 
that the designation of critical habitat for the Pecos assiminea does 
not pose significant takings implications.


    In accordance with Executive Order 13132, this rule does not have 
significant Federalism effects. A Federalism assessment is not 
required. In keeping with Department of the Interior policy, the 
Service requested information from, and coordinated development of this 
critical habitat designation with, appropriate State resource agencies 
in New Mexico and Texas. The impact of the designation on State and 
local governments and their activities was fully considered in the 
economic analysis. As discussed above, the designation of critical 
habitat for the Pecos assiminea would have little incremental impact on 
State and local governments and their activities. In fact, the 
designation of critical habitat may have some benefit to the State and 
local resource agencies in that the areas essential to the conservation 
of this species are more clearly defined, and the primary constituent 
elements of the habitat necessary to the conservation of this species 
are specifically identified.

Civil Justice Reform

    In accordance with Executive Order 12988, the Office of the 
Solicitor has determined that the rule does not unduly burden the 
judicial system and that it meets the requirements of sections 3(a) and 
3(b)(2) of the Order. We are designating critical habitat in accordance 
with the provisions of the Act, as amended. This rule uses standard 
property descriptions and identifies the primary constituent elements 
within the designated areas to assist the public in understanding the 
habitat needs that are essential for the conservation of the Pecos 

Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.)

    This rule does not contain new or revised information collection 
for which Office of Management and Budget approval is required under 
the Paperwork Reduction Act. An agency may not conduct or sponsor, and 
a person is not required to respond to, a collection of information 
unless it displays a currently valid OMB control number.

National Environmental Policy Act

    It is our position that, outside the Tenth Circuit, we do not need 
to prepare environmental analyses as defined by the NEPA in connection 
with designating critical habitat under the Act. We published a notice 
outlining our reasons for this determination in the Federal Register on 
October 25, 1983 (48 FR 49244). This assertion was upheld in the courts 
of the Ninth Circuit

[[Page 46329]]

[(Douglas County v. Babbitt, 48 F.3d 1495 (9th Cir. Ore. 1995), cert. 
denied 116 S. Ct. 698 (1996).] However, when the range of the species 
includes States within the Tenth Circuit, such as that of the four 
invertebrates, pursuant to the Tenth Circuit ruling in Catron County 
Board of Commissioners v. U.S. Fish and Wildlife Service, 75 F.3d 1429 
(10th Cir. 1996), we undertake a NEPA analysis for critical habitat 
designation. We completed an environmental assessment and finding of no 
significant impact on the designation of critical habitat for the Pecos 

Secretarial Order 3206: American Indian Tribal Rights, Federal-Tribal 
Trust Responsibilities, and the Endangered Species Act

    The purpose of Secretarial Order 3206 (Secretarial Order) is to 
``clarif(y) the responsibilities of the component agencies, bureaus, 
and offices of the Department of the Interior and the Department of 
Commerce, when actions taken under authority of the Act and associated 
implementing regulations affect, or may affect, Indian lands, tribal 
trust resources, or the exercise of American Indian tribal rights.'' If 
there is potential that a tribal activity could cause either direct or 
incidental take of a species proposed for listing under the Act, then 
meaningful government-to-government consultation will occur to try to 
harmonize the Federal trust responsibility to tribes and tribal 
sovereignty with our statutory responsibilities under the Act. The 
Secretarial Order also requires us to consult with tribes if the 
designation of an area as critical habitat might impact tribal trust 
resources, tribally owned fee lands, or the exercise of tribal rights. 
However, no known tribal activities could cause either direct or 
incidental take of the four species in this final rule, and no tribal 
lands or tribal trust resources are anticipated to be affected by the 
designation of critical habitat.

References Cited

    A complete list of all references cited in this rulemaking is 
available upon request from the New Mexico Ecological Services Field 
Office (see ADDRESSES section).


    The primary authors of this rule are the New Mexico Ecological 
Services Field Office staff (see ADDRESSES section) (telephone 505/346-

List of Subjects in 50 CFR Part 17

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

Regulation Promulgation

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


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

    Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C. 
4201-4245; Pub. L. 99-625, 100 Stat. 3500; unless otherwise noted.

2. Amend Sec.  17.11(h) as follows:
a. Add Pecos assiminea, Koster's springsnail, and Roswell springsnail 
in alphabetical order under ``SNAILS;'' and
b. Add Noel's amphipod in alphabetical order under ``CRUSTACEANS,'' to 
the List of Endangered and Threatened Wildlife to read as follows:

Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

                          Species                                                      Vertebrate
------------------------------------------------------------                        population where                   When       Critical     Special
                                                                 Historic Range       endangered or      Status       listed      habitat       rules
            Common name                  Scientific name                               threatened

                                                                      * * * * * * *

                                                                      * * * * * * *
Pecos assiminea....................  Assiminea pecos.......  U.S.A. (NM, TX)......  NA                          E     17.95(f)           NA

                                                                      * * * * * * *
Springsnail, Koster's..............  Juturnia kosteria.....  U.S.A. (NM)..........  NA                          E           NA           NA
Springsnail, Roswell...............  Pyrgulopsis             U.S.A. (NM)..........  NA                          E           NA           NA

                                                                      * * * * * * *
Amphipod, Noel's...................  Gammarus desperatus...  U.S.A. (NM)..........  NA                          E           NA           NA

                                                                      * * * * * * *

3. Amend Sec.  17.95 (f) by adding critical habitat for Pecos assiminea 
in the same order as this species occurs in Sec.  17.11(h).

Sec.  17.95  Critical habitat--fish and wildlife.

* * * * *
    (f) Clams and snails.
* * * * *
    Pecos assiminea (Assiminea pecos)
    1. Within the areas designated below as critical habitat, the 
primary constituent elements for Pecos assiminea include:
    (i) Permanent, flowing, unpolluted, fresh to moderately saline 
    (ii) Moist or saturated soil at stream or spring run margins with 
native vegetation growing in or adapted to aquatic or very wet 
environment, such as salt grass or sedges; and
    (iii) Stable water levels with natural diurnal and seasonal 
    2. Critical habitat is depicted for the Pecos assiminea in Pecos 
County, Texas, at the Diamond Y Springs Complex. The designation 
includes the Diamond Y Spring, which is located at UTM 13- 698261 E, 
3431372 N, and 6.8 km (4.2

[[Page 46330]]

mi) of its outflow, ending at UTM 13- 701832 E, 3436112 N, about 0.8 km 
(0.5 mi) downstream of the State Highway 18 bridge crossing. Also 
included is 0.8 km (0.5 mi) of Leon Creek upstream of the confluence 
with Diamond Y Draw. All surrounding riparian vegetation and mesic soil 
environments within the spring outflow and portion of Leon Creek are 
also designated as these areas are considered habitat for the Pecos 
assiminea. Critical habitat is also depicted for the Pecos assiminea in 
Reeves County, Texas, at the East Sandia Spring complex. East Sandia 
Spring is located at UTM 13-621366 E, 342929 N. Critical habitat 
includes the springhead itself, surrounding seeps, and all submergent 
vegetation and moist soil habitat found at the margins of these areas. 
These areas are considered habitat for the Pecos assiminea.
    (i) Pecos County, Texas, including the Diamond Y Springs Complex, 
located at longitude -102.923461 and latitude 30.999271, and 
approximately 6.8 km (4.2 mi) of the spring outflow ending at about 0.8 
km (0.5 mi) downstream of the State Highway 18 bridge crossing 
(approximately longitude -102.885137 and latitude 31.041405). Also 
included is approximately 0.8 km (0.5 mi) of Leon Creek upstream of the 
confluence with Diamond Y Draw. All surrounding riparian vegetation and 
mesic soil environments within the spring, outflow, and portion of Leon 
Creek are also proposed for designation as these areas are considered 
habitat for the Pecos assiminea. Legal description (geographic 
projection, North American Datum 83): Longitude (decimal degrees), 
Latitude (decimal degrees):

-102.905319869746634, 31.022089444891570; -102.887036917654868, 
31.043947412173729; -102.884194716234887, 31.042760908977833; -
102.885135806784476, 31.040116604685526; -102.886447071974004, 
31.038190792077721; -102.886620885824385, 31.037813677269160; -
102.890251036381329, 31.035783323856453; -102.892481680821120, 
31.034679908957198; -102.893548121939546, 31.033842414359302; -
102.893785401930572, 31.033086360646934; -102.893745950415067, 
31.032373282069056; -102.894097678233564, 31.031429114358268; -
102.895544792411911, 31.030835296062797; -102.896058768051944, 
31.030036256911551; -102.898010410716566, 31.029070675153459; -
102.898781252646117, 31.029130733495535; -102.899944293890798, 
31.028912200684612; -102.900716178554276, 31.028924768711160; -
102.901441262661692, 31.028556604651808; -102.901948928625941, 
31.028042412007075; -102.901688880906221, 31.027325744767865; -
102.901714918210303, 31.026138774702297; -102.901732622700223, 
31.025331634924694; -102.901817954640350, 31.023955646131167; -
102.902125889274174, 31.022488286611136; -102.902640803335373, 
31.021641737279424; -102.903610272253857, 31.020185129479138; -
102.903508335417825, 31.019803505987209; -102.904231258688768, 
31.019530280313123; -102.905008267695379, 31.019305424852949; -
102.905627160458280, 31.018745526192433; -102.905862223627835, 
31.018084401107885; -102.907438011441329, 31.016637604571564; -
102.908402165790250, 31.015418349965021; -102.909312205831228, 
31.014150714293240; -102.909665778900688, 31.013111534294385; -
102.910342839052220, 31.012410065631975; -102.911174902560035, 
31.012186062876218; -102.912113070098556, 31.012153756020012; -
102.912844195573911, 31.011500644598044; -102.913370338091369, 
31.010131773029197; -102.914161736135028, 31.009242148253836; -
102.915610463748450, 31.008553125409257; -102.917106029547554, 
31.008244810453860; -102.918875138268959, 31.008035883431738; -
102.919664405186026, 31.007241180720893; -102.920460878479304, 
31.006114116159939; -102.920933820519480, 31.004649359449264; -
102.921603523207537, 31.004280181687651; -102.921961044126064, 
31.003051041389284; -102.922105288280434, 31.001485991578242; -
102.923062919493049, 31.000551488397821; -102.924338893382782, 
31.000192054013731; -102.925434072210962, 31.000542142822137; -
102.925748330937964, 31.001307135185360; -102.925543882342382, 
31.003108703491051; -102.924514657475115, 31.004802011677008; -
102.923332386691257, 31.005922892971402; -102.922655466250575, 
31.006624436236699; -102.921313967399342, 31.007457756682811; -
102.921298502243019, 31.008169949149053; -102.921890429628803, 
31.008844431891216; -102.922088249987723, 31.009892533060658; -
102.920305700167233, 31.010718735844538; -102.918990962464960, 
31.010317563552466; -102.917661775715189, 31.010581089582509; -
102.915939472406691, 31.011170723093645; -102.915640066348502, 
31.012258293740160; -102.915233503111892, 31.013201643466406; -
102.914004171668253, 31.013941704157816; -102.912955733451284, 
31.013972240169043; -102.912389969275623, 31.014628028040637; -
102.912099833183859, 31.015288275173923; -102.912212159226485, 
31.015195101507882; -102.910513768505638, 31.017209923999967; -
102.908484529126227, 31.019219357013320; -102.906961764318297, 
31.020762017382609; -102.906510334381181, 31.021229648922475; -
102.906323124324715, 31.022224022537589; -102.905476410341578, 
31.023112694758801; -102.904572468616138,

[[Page 46331]]

31.024095422710321; -102.904098125726293, 31.025607579972412; -
102.904512146691772, 31.026849198511329; -102.904475741511831, 
31.028510959127807; -102.903447935740203, 31.030109108839046; -
102.901831302956197, 31.030890242225727; -102.900225068829968, 
31.031196566903024; -102.897834397853146, 31.032060033587637; -
102.896823149655987, 31.032898465556570; -102.895449713462554, 
31.035155846795476; -102.894484140543042, 31.036422464608236; -
102.892135869908444, 31.037856459486278; -102.890355694384951, 
31.038539777638526; -102.889015567482971, 31.039277771567470; -
102.888427464446750, 31.040930483816535; -102.887036917654868, 
    (ii) Reeves County, Texas, at the East Sandia Spring complex. East 
Sandia Spring is located at longitude -103.728918, latitude 30.991012. 
The designation includes the springhead itself, surrounding seeps, and 
all submergent vegetation and moist soil habitat found at the margins 
of these areas. These areas are considered habitat for the Pecos 
assiminea. Legal description (geographic projection, North American 
Datum 83): Longitude (decimal degrees), Latitude (decimal degrees): -
103.729296238487009, 30.990656960487129; -103.731179077171333, 
30.989695620405591; -103.730160658036496, 30.991850361242875; -
103.727182653076312, 30.992477028891606; -103.729159475230986, 
30.988608062418542; -103.731179077171333, 30.989695620405591.
    3. A map of the Diamond Y Springs Complex and East Sandia Spring 
Complex follows:


[[Page 46332]]


[[Page 46333]]

    Dated: August 1, 2005.
Craig Manson,
Assistant Secretary for Fish and Wildlife and Parks.
[FR Doc. 05-15486 Filed 8-8-05; 8:45 am]