[Federal Register: July 17, 2007 (Volume 72, Number 136)]
[Rules and Regulations]               
[Page 39247-39283]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr17jy07-11]                         


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Part III





Department of the Interior





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Fish and Wildlife Service



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50 CFR Part 17



 Endangered and Threatened Wildlife and Plants; Designation of Critical 
Habitat for the Peck's Cave Amphipod, Comal Springs Dryopid Beetle, and 
Comal Springs Riffle Beetle; Final Rule


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AU75

 
Endangered and Threatened Wildlife and Plants; Designation of 
Critical Habitat for the Peck's Cave Amphipod, Comal Springs Dryopid 
Beetle, and Comal Springs Riffle Beetle

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), are 
designating critical habitat for the Peck's cave amphipod (Stygobromus 
pecki), Comal Springs dryopid beetle (Stygoparnus comalensis), and 
Comal Springs riffle beetle (Heterelmis comalensis) in areas of 
occupied, spring-related aquatic habitat in Texas under the Endangered 
Species Act of 1973, as amended (Act). The three listed species are 
known only from four spring systems in central Texas: Comal Springs and 
Hueco Springs in Comal County, and Fern Bank Springs and San Marcos 
Springs in Hays County. The total area designated as critical habitat 
for the amphipod is about 38.5 acres (ac) (15.6 hectares (ha)), for the 
dryopid beetle it is about 39.5 ac (16.0 ha), and for the riffle beetle 
it is about 30.3 ac (12.3 ha).

DATES: This rule becomes effective on August 16, 2007.

FOR FURTHER INFORMATION CONTACT: Adam Zerrenner, Field Supervisor, 
Austin Ecological Services Office, 10711 Burnet Road, Suite 200, 
Austin, TX 78758 (telephone 512-490-0057; facsimile 512-490-0974).

SUPPLEMENTARY INFORMATION:

Background

    It is our intent to discuss only those topics directly relevant to 
the designation of critical habitat in this rule. For more information 
on these species, refer to the final rule listing the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle 
that was published in the Federal Register on December 18, 1997 (62 FR 
66295).
    All three of the listed species included in this final rule for 
critical habitat designation are freshwater invertebrates. The Peck's 
cave amphipod is an eyeless, subterranean (below ground) arthropod that 
has been found in Comal Springs and Hueco Springs (also spelled Waco 
Springs). Both spring systems are located in Comal County, Texas. The 
Comal Springs dryopid beetle is a subterranean insect with vestigial 
(poorly developed, non-functional) eyes. The species has been found in 
two spring systems, Comal Springs and Fern Bank Springs, that are 
located in Comal and Hays Counties, respectively. The Comal Springs 
riffle beetle is an aquatic insect that is found in and primarily 
restricted to surface water associated with Comal Springs in Comal 
County and with San Marcos Springs in Hays County.
    The four spring systems (Comal, Fern Bank, Hueco, and San Marcos) 
designated as critical habitat units are produced by discharge of 
aquifer spring water along the Balcones fault zone at the edge of the 
Edwards Plateau in central Texas. The source of water flows for Comal 
Springs and San Marcos Springs is the San Antonio segment of the 
Edwards Aquifer. This aquifer is characterized by highly varied, below 
ground spaces that have been hollowed out within limestone bedrock 
through dissolution by rainwater. Groundwater is held and conveyed 
within these hollowed-out spaces, which range in size from honeycomb-
like pores to large caverns. The San Antonio segment of the aquifer 
occurs in a crescent-shaped section over a distance of 176 miles (mi) 
(283 kilometers (km)), from the town of Brackettville in Kinney County 
on the segment's west side over to the town of Kyle in Hays County at 
the segment's northeast side. Groundwater generally moves from recharge 
areas in the southwest part of the San Antonio segment and travels 
toward discharge areas in the northeast part of the segment, which 
includes Comal Springs and San Marcos Springs. The area that recharges 
groundwater coming to Comal Springs may occur as much as 62 mi (100 km) 
away from the springs (Brune 1981, p. 130). Hueco Springs is recharged 
locally from the local watershed basin and possibly by the San Antonio 
segment of the Edwards Aquifer (Guyton and Associates 1979, p. 2). The 
source of water for Fern Bank Springs has not been determined. Fern 
Bank Springs discharges water from the upper member of the Glen Rose 
Formation, and its flow could originate primarily from that unit; 
however, water discharged from the springs could also be (1) Drainage 
from the nearby Edwards Aquifer recharge zone, (2) water lost from the 
Blanco River, or (3) a combination of all three sources (Veni 2006, 
p.1).
    Comal Springs and San Marcos Springs are the two largest spring 
systems in Texas with respective mean annual flows of 284 and 170 cubic 
feet per second (8 and 5 cubic meters per second) (Fahlquist and 
Slattery 1997, p. 1; Slattery and Fahlquist 1997, p. 1). Both spring 
systems emerge as a series of spring outlets along the Balcones fault 
that follows the edge of the Edwards Plateau in Texas. Fern Bank 
Springs and Hueco Springs have considerably smaller flows and consist 
of one main spring with several satellite springs or seep areas.
    The four spring systems designated for critical habitat are 
characterized by high water quality and relatively constant water 
flows, with temperatures that range from 68 to 75 [deg]F (Fahrenheit) 
(20 to 24 [deg]C (Celsius)). Due to the underlying limestone aquifer, 
discharged water from these springs has a carbonate chemistry (Ogden et 
al. 1986, p. 103). Although flows from San Marcos Springs can vary 
according to fluctuations in the source aquifer, records indicate that 
this spring system has never ceased flowing. San Marcos Springs has 
been monitored since 1894, and has exhibited the greatest flow 
dependability of any major spring system in central Texas (Puente 1976, 
p. 27). Comal Springs has a flow record nearly comparable to that of 
San Marcos Springs; however, Comal Springs ceased flowing from June 13 
to November 3, 1956, during a severe drought (U.S. Army Corps of 
Engineers 1965, p. 59). Water pumping from the aquifer contributed to 
cessation of flow at Comal Springs during the drought period (U.S. Army 
Corps of Engineers 1965, p. 59). Hueco Springs has gone dry a number of 
times in the past during drought periods (Puente 1976, p. 27; Guyton 
and Associates 1979, p. 46). Although flow records are unavailable for 
Fern Bank Springs, the spring system is considered to be perennial 
(Barr 1993, p. 39).
    Each of the four spring systems and related subterranean aquifers 
typically provide adequate resources to sustain life cycle functions 
for resident populations of the Peck's cave amphipod, Comal Springs 
dryopid beetle, and Comal Springs riffle beetle. However, a primary 
threat to the three invertebrate species is the potential failure of 
spring flow due to drought or excessive groundwater pumping, which 
could result in loss of aquatic habitat for the species. Although these 
invertebrate species persisted at Comal Springs in the 1950s despite 
drought conditions (Bowles et al. 2003, p. 379), all three species are 
aquatic and require water to complete their individual life cycles.
    Bowles et al. (2003, p. 379) pointed out that the mechanism by 
which the Comal Springs riffle beetle survived the drought and the 
extent to which its population was negatively impacted are

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uncertain. Bowles et al. (2003, p. 379) speculated that the riffle 
beetle may be able to retreat back into spring openings or burrow down 
to wet areas below the surface of the streambed.
    Barr (1993, p. 55) found Comal Springs dryopid beetles in spring 
flows with low volume discharge as well as high volume discharge and 
suggested that presence of the species did not necessarily depend on a 
high spring flow. However, Barr (1993, p. 61) noted that effects on 
both subterranean species (dryopid beetle and amphipod) from extended 
loss of spring flow and low aquifer levels could not be predicted due 
to limited knowledge about their life cycles.

Previous Federal Actions

    Information about previous Federal actions for Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle 
can be found in our proposal to designate critical habitat for these 
species published in the Federal Register on July 17, 2006 (71 FR 
40588). On March 16, 2007, we announced the availability of our draft 
economic analysis, and we reopened the public comment period on the 
proposed rule (72 FR 12585). The reopened public comment period ended 
on April 16, 2007.

Summary of Comments and Recommendations

    We requested written comments from the public on the proposed 
designation of critical habitat for Peck's cave amphipod, Comal Springs 
dryopid beetle, and Comal Springs riffle beetle in the proposed rule 
published on July 17, 2006 (71 FR 40588) and in our March 16, 2007, 
Federal Register notice (72 FR 12585). We also contacted appropriate 
Federal, State, and local agencies; scientific organizations; and other 
interested parties and invited them to comment on the proposed rule.
    During the comment period that opened on July 17, 2006, and closed 
on September 15, 2006, we received eight responses directly addressing 
the proposed critical habitat designation: four from peer reviewers, 
one from a State agency, and three from organizations or individuals. 
The response we received from the State agency, the Texas Department of 
Transportation, indicated that the proposed critical habitat 
designations for these species were ``prudently identified'' by the 
Service. However, that agency did not offer any other comments. After 
completing the draft economic analysis, we reopened the comment period 
between March 16, 2007, and April 16, 2007 (72 FR 12585). During the 
second comment period, we received one comment from a peer reviewer and 
four from organizations; two of which included comments on the economic 
analysis. Responses to all comments were grouped by those from peer 
reviewers, followed by public comments. These comments are addressed in 
the following summary and incorporated into the final rule as 
appropriate. We did not receive any requests for a public hearing and 
thus no public hearing was held.

Peer Review

    In accordance with our policy published on July 1, 1994 (59 FR 
34270), we solicited expert opinions from nine knowledgeable 
individuals with scientific expertise that included familiarity with 
the species, the geographic region in which the species occur, and 
conservation biology principles. We received responses from four of the 
peer reviewers. Although none of the peer reviewers disagreed with our 
methods in designating critical habitat for the Peck's cave amphipod, 
Comal Springs dryopid beetle, and Comal Springs riffle beetle, three of 
the responses indicated that the critical habitat designation failed to 
address the broader issue of maintaining spring flows, ecosystem 
functioning, and groundwater levels within the Edwards Aquifer. Also, 
two of the peer reviewers disagreed with the reasoning we presented in 
our determination of Primary Constituent Element (PCE) 4. Three of the 
peer reviewers' responses provided additional information, 
clarifications, and suggestions to improve the final critical habitat 
rule. We address peer reviewer comments in the following summary and 
have incorporated them into the final rule as appropriate.
    We reviewed all comments received from the peer reviewers and the 
public for substantive issues and new information regarding critical 
habitat for the Peck's cave amphipod, Comal Springs dryopid beetle, and 
Comal Springs riffle beetle, and address them in the following summary.

Peer Reviewer Comments

    1. Comment: One of the critical factors affecting the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle 
is continued natural spring flows. Adequate or minimum spring flows 
should be included as a PCE.
    Our Response: We agree that adequate water quantity is necessary 
for the survival of the three invertebrate species. We indicated that 
availability and access to water at the spring sites are important 
factors in maintaining the life history functions of the Peck's cave 
amphipod, the Comal Springs dryopid beetle, and the Comal Springs 
riffle beetle by highlighting the role of water in the descriptions of 
PCEs 1, 2, and 3 of this final rule. We clarified the language for PCE 
3 to highlight the importance of spring flows in maintaining adequate 
dissolved oxygen levels. We also state in the Special Management 
Considerations section of this rule that prolonged cessation of spring 
flows as a result of the loss of hydrological connectivity within the 
aquifer may require special management considerations, such as 
maintenance of sustainable groundwater use and subsurface flows.
    2. Comment: PCE 5 should be corrected to indicate that the 
substrate habitat of the Peck's cave amphipod, Comal Springs dryopid 
beetle, and Comal Springs riffle beetle should also be free of sand and 
silt.
    Our Response: We incorporated this suggestion into PCE 5.
    3. Comment: Riparian vegetation in the immediate vicinity of the 
spring openings are likely not the food source for any of the three 
invertebrate species, as described in PCE 4. Aquatic invertebrates 
typically feed on plant material well after it has been mechanically 
broken down. Flow in the vicinity of spring openings would quickly 
carry away leaf litter and other plant material before it could become 
mechanically broken down. The detritus that comprises the food source 
for the Comal Springs dryopid beetle is most likely introduced into the 
aquifer at recharge points far upstream of the spring openings (i.e., 
within the recharge area of the aquifer). Similarly, the food source 
for the Peck's cave amphipod is likely found within the Edwards 
Aquifer. Specifically, the food source may be composed of material that 
enters through the recharge area of the aquifer and the many other 
organisms that co-occur within the aquifer. Aquatic macrophyte (i.e., 
large plant) roots may be a source of detritus for invertebrates in a 
spring-run downstream of a spring opening. However, the roots are 
likely not the food sources for the Peck's cave amphipod, because the 
amphipod is found only near the spring openings and within the aquifer. 
Because the riparian habitats around the springs are likely not 
influencing these three species, the critical habitat designations only 
represent the smallest part of their habitats or range.
    Our Response: The Comal Springs dryopid beetle has only been 
observed near spring outlets. Adults have been

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found on rocks and cotton cloth lures in spring openings. They have 
also been observed on rotting wood above spring upwellings near tree 
roots growing just under the gravel substrate more than 16 feet (ft) (5 
meters (m)) from the shore of Landa Lake (Gibson et al. 2006, p. 3). 
Larvae of this species do not have gills and are considered 
terrestrial, as they typically inhabit moist soil along stream banks 
(Brown 1987, p. 253; Ulrich 1986, p. 325). Because of these 
characteristics, we believe Comal Springs dryopid beetle larvae feed on 
roots and decaying vegetation in areas just above the aquifer (i.e., 
subsurface area) water line. We believe the Peck's cave amphipod likely 
consumes both animals and plants, and feeds both within the aquifer and 
on detritus in areas near spring outlets where plant roots interface 
with spring water (Gibson 2006, p. 1). Therefore, we believe critical 
habitat should include the riparian vegetation as a food source for the 
Peck's cave amphipod and Comal Springs dryopid beetle.
    4. Comment: The designation of 50-ft distances around spring 
openings seems reasonable to protect and maintain the subsurface 
vegetation profile in the immediate area of the springs; however, the 
detrital food base could come from sources at greater distances.
    Our Response: Although there may be some contribution of detrital 
food sources from greater distances within the aquifer, we are unaware 
of any data that indicate this. As explained in our response to Comment 
3 above, there is available information that suggests that riparian 
vegetation near the spring openings is an important habitat component 
for the Peck's cave amphipod, Comal Springs dryopid beetle, and Comal 
Springs riffle beetle, and may provide a source of food for these 
species.
    5. Comment: Under PCE 1, the pesticides mentioned only refer to 
classes such as organochlorines, organophosphates, and chlorinated 
hydrocarbons. The Service should consider pesticide classes such as 
insect growth regulators as well as pharmaceuticals that could enter 
groundwater sources. The Service should clarify the differences between 
these compounds and their potential effects on the listed species.
    Our Response: We have added pharmaceuticals to the list of 
potential pollutants discussed under PCE 1 in response to this comment. 
There are no scientific studies available on the potential effects that 
each of these pollutants have on the Peck's cave amphipod, Comal 
Springs dryopid beetle, and Comal Springs riffle beetle, so we are 
unable to address the potential effects of these pollutants in the 
final rule. We acknowledge the importance of maintaining high water 
quality within the Edwards Aquifer, and we will work to evaluate and 
address the effects of pollutants during the recovery planning and 
implementation processes for these species.
    6. Comment: With regard to PCE 1, Hueco Springs and Fern Bank 
Springs may be influenced by storm water. Can the claim be made that 
the spring systems are characterized by high water quality?
    Our Response: Spring systems in general may have some short-term 
changes in water quality after storm events. Hueco Springs and Fern 
Bank Springs are smaller in size and may have more local recharge 
features than Comal Springs and San Marcos Springs. Although these 
characteristics may make them more susceptible to short-term changes in 
water quality after storm events, the Service has no data to indicate 
that these temporary changes negatively affect the species that occur 
near the spring openings. Comal and San Marcos Springs may also be 
affected by local runoff from storm events based on tracer tests by the 
Edwards Aquifer Authority. We consider all of the spring systems 
occupied by the Peck's cave amphipod, Comal Springs dryopid beetle, and 
Comal Springs riffle beetle to have high water quality.
    7. Comment: There is a strong likelihood that additional 
populations of the Comal Springs riffle beetle occur in or around the 
various spring outlets in the bottoms of Spring Lake and Landa Lake, 
where substrate is sufficiently coarse to serve as habitat.
    Our Response: We believe this is addressed through the designation 
of all aquatic habitat within Landa Lake where springs are present and 
PCEs are known to exist for the Peck's cave amphipod and Comal Springs 
dryopid beetle. However, this point was clarified in the Critical 
Habitat Designation section of this final rule describing the 
designated critical habitat areas within Landa Lake for the Comal 
Springs Unit in Comal County, Texas.
    8. Comment: Paragraph 8 under ``Adverse Modification Standard'' 
states that ``ongoing human activities that occur outside the proposed 
critical habitat are unlikely to threaten the physical and biological 
features of the proposed critical habitat.'' However, if there is an 
increase in pumping water from the aquifer prior to the ruling on 
critical habitat, then that new pumping may impact PCEs 2, 3, and 5.
    Our Response: We agree with the commenter and have clarified the 
language in the Effects of Critical Habitat Designation section that 
groundwater pumping from the Edwards Aquifer may affect critical 
habitat and require section 7 consultation.
    9. Comment: The critical habitat designations may provide benefits 
to the Peck's cave amphipod, Comal Springs dryopid beetle, and Comal 
Springs riffle beetle on a local scale (i.e., in the immediate area of 
the spring openings), but they do not offer protections to the Edwards 
Aquifer ecosystem. Critical habitat for these species should be 
extended to include the entire Edwards Aquifer, including subsurface 
areas. Until parts of the Edwards Aquifer can be shown to not have 
populations of these two species, the most sensible solution is to 
assume that the entire aquifer is critical habitat. Also, there are 
ecosystem processes (e.g., organic matter inputs, interactions with 
other species, nutrient availability) that are not addressed by the 
PCEs and may be addressed by designating the entire Edwards Aquifer.
    Our Response: Organic matter and nutrient availability are 
addressed in PCE 4. We recognize the importance of maintaining 
ecosystem integrity and functionality and implementing strategies to 
protect the entire Edwards Aquifer. However, we reviewed all available 
information that pertains to the occurrence of the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle 
beetle. Although the Peck's cave amphipod and the Comal Springs dryopid 
beetle are believed to be subterranean, we have no information 
available to show that the entire Edwards Aquifer ecosystem is occupied 
by the species. Nor do we believe the PCEs are found throughout the 
aquifer. We cannot demonstrate that the entire aquifer is essential to 
the conservation of the species. Although the entire aquifer has not 
been designated as critical habitat, Federal activities outside of 
designated critical habitat areas are subject to review under section 7 
of the Act if these activities may adversely affect the PCEs within the 
critical habitat designation.
    10. Comment: The PCEs do nothing to safeguard the source of the 
water--the Edwards Aquifer, upon which the invertebrates depend. A 
comprehensive plan for the Edwards Aquifer with constraints on 
groundwater pumping and pollution of recharge should be developed.
    Our Response: Designating critical habitat is only one means to aid 
in the habitat conservation of listed species. Efforts to address 
threats to the Edwards Aquifer can be undertaken through the

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recovery implementation process for these and the other federally-
listed species that depend on the aquifer for their survival. For 
example, we are working with a large number of partner agencies and 
organizations, including the Edwards Aquifer Authority, to develop an 
Edwards Aquifer Recovery Implementation Program (RIP) to address 
threats to the Edwards Aquifer. The Edwards Aquifer Authority (EAA) is 
the agency with the responsibility to manage, enhance, and protect the 
Edwards Aquifer system through a variety of mechanisms including the 
issuing of pumping permits for use of water from the aquifer. We intend 
to continue our close work with the EAA and others for conservation of 
the springs that flow from the Edwards Aquifer.

Public Comments

    11. Comment: It seems imprudent to designate critical habitat for 
the Peck's cave amphipod, Comal Springs dryopid beetle, and Comal 
Springs riffle beetle, when this would provide no benefit to the 
species beyond that provided by listing of the species and any 
subsequent evaluation of activities in light of section 7 consultation 
requirements.
    Our Response: The Role of Critical Habitat in Actual Practice of 
Administering and Implementing the Act section in the proposed rule has 
been removed from this final rule. We recognize some benefits to 
critical habitat designations. Federal activities outside of designated 
critical habitat areas are subject to review under section 7 of the Act 
if these activities may adversely affect the PCEs within the critical 
habitat designation. The Ninth Circuit Court's decision in Gifford 
Pinchot Task Force v. United States Fish and Wildlife Service, 378 F.3d 
1059 (9th Cir 2004) (hereinafter Gifford Pinchot) requires 
consideration of the recovery of species. Thus, under this court 
ruling, and our implementation of Section 7 of the Act, critical 
habitat designations may provide greater benefits to the recovery of a 
species. Also, we have found that critical habitat designations serve 
to educate landowners, State and local governments, and the public 
regarding the potential conservation value of the areas designated.
    12. Comment: This critical habitat designation is not beneficial, 
especially in light of a recent initiation of a RIP for the endangered 
species of the Edwards Aquifer under the encouragement of the Service.
    Our Response: In designating critical habitat areas, we have 
reviewed the overall approach to the conservation of the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle 
undertaken by local, Federal, and State agencies; and by private 
organizations operating within the species' range since their listing. 
As noted above, we are very supportive of the RIP process; however, 
this process is in its initial stages of development, and therefore we 
were not able to consider the potential conservation benefits of the 
RIP to these species in our critical habitat determination. Also, as 
stated in our response to Comment 11 above, we recognize several 
benefits to designating critical habitat.
    13. Comment: In the Critical Habitat section of the proposed rule, 
the Service understates the extent to which critical habitat 
designations provide additional protection for species above and beyond 
the prohibition of take that comes with federally listing species as 
endangered or threatened. This approach is legally and scientifically 
unsubstantiated, and it shortchanges the goals of the Act to provide 
for the conservation and recovery of listed species.
    Our Response: As discussed above, we agree that the designation of 
critical habitat can serve positive purposes, but we also believe it is 
only one tool for managing listed species' habitat. In addition to the 
designation of critical habitat, we have determined that other 
conservation mechanisms, including the recovery planning process, 
section 6 funding to States, section 7 consultations, management plans, 
Safe Harbor agreements, and other on-the-ground strategies, contribute 
to species' conservation. We will continue to work with local partner 
organizations (such as the Edwards Aquifer Authority, San Antonio Water 
System, local municipalities, Texas Parks and Wildlife Department, and 
others) through the RIP, to develop means for voluntary conservation of 
habitats for these listed species. We believe these other conservation 
measures often provide incentives for project planners and greater 
conservation benefits than critical habitat designation.
    14. Comment: There does not appear to be a clear correlation 
between the needs of the Peck's cave amphipod, Comal Springs dryopid 
beetle, and Comal Springs riffle beetle and particular spring flow 
conditions to require such special management considerations.
    Our Response: There is information to indicate that availability 
and access to water at the spring sites are important factors in 
maintaining the life history functions (i.e., those functions that are 
dependent on high water quality, adequate water temperature, and 
adequate dissolved oxygen levels) of the Peck's cave amphipod, Comal 
Springs dryopid beetle, and Comal Springs riffle beetle, as described 
under PCEs 1, 2, and 3. We believe that prolonged cessation of spring 
flows as a result of the loss of hydrological connectivity within the 
aquifer may require special management considerations, such as 
maintenance of sustainable groundwater use and subsurface flows.
    15. Comment: The proposed rule only designates as critical habitat 
the aquatic areas where the Peck's cave amphipod, Comal Springs dryopid 
beetle, and Comal Springs riffle beetle are found, plus a 50-ft 
distance from the spring outlets. The proposed rule does nothing to 
control water quality impacts from activities occurring in the 
contributing and recharge zones of the aquifer, limiting the critical 
habitat to only a 50-ft buffer beyond the spring outlets to protect the 
species' food sources. Such a buffer would fail to protect the water 
quality in the aquatic habitat. Typical buffers to protect water 
quality tend to be at least 100 ft on each side of sensitive waters. 
The critical habitat should likewise at least accommodate such extended 
buffers to help protect water quality in the aquatic habitat.
    Our Response: We proposed designating critical habitat in areas 
that we have determined are occupied by the Peck's cave amphipod, Comal 
Springs dryopid beetle, and Comal Springs riffle beetle; contain 
sufficient PCEs to support life-history functions essential for the 
conservation of the species; and require special management or 
protection. The 50-ft (15.2-m) distances define the lateral extent of 
critical habitat that contains PCEs with respect to food sources in 
root/water interfaces. Use of a 100-ft (30.4-m) buffer for this 
critical habitat designation would extend the boundary to include areas 
not known to contain the PCEs; therefore, use of this larger buffer is 
not consistent with the criteria used to identify critical habitat.
    The designation of critical habitat requires Federal agencies to 
consult with us when activities they fund, authorize, or carry out may 
affect the critical habitat of a listed species. Consultation is 
required where projects may (indirectly or directly) adversely affect 
critical habitat, even if those projects occur outside designated 
critical habitat (e.g., the contributing and recharge zones of the 
aquifer).
    16. Comment: The final rule should include the minimal spring flow 
rates provided in the EAA's 2005 Draft Habitat Conservation Plan.
    Our Response: The EAA's 2005 Draft Habitat Conservation Plan (HCP) 
has not

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been finalized, nor have we issued a permit for the EAA. We have not 
analyzed spring flow rates from the 2005 Draft HCP for effects to the 
Peck's cave amphipod, Comal Springs dryopid beetle, and Comal Springs 
riffle beetle. In addition, flow from Fern Bank Springs is from the 
Trinity Aquifer, not the Edwards Aquifer. Thus, the draft EAA HCP does 
not address the maintenance of Fern Bank Springs habitat and that 
population of the Comal Springs dryopid beetle.
    17. Comment: The economic analysis should include the benefits of 
designating critical habitat for the invertebrate species. Without 
estimating the benefits to designation, the costs seem unreasonably 
high, and therefore paint the conservation effort in a negative light. 
A full benefits analysis should include direct, indirect, and non-use 
benefits.
    Our Response: As stated in Chapter 1 of the final economic 
analysis, a potential direct benefit of the rulemaking is the potential 
to enhance conservation of the species. The published economics 
literature has documented that social welfare benefits can result from 
the conservation and recovery of endangered and threatened species. 
However, in its guidance for implementing Executive Order 12866, OMB 
acknowledges that it may not be feasible to monetize, or even quantify, 
the benefits of environmental regulations due to either an absence of 
defensible, relevant studies or a lack of resources on the implementing 
agency's part to conduct new research. Rather than rely on economic 
measures, we believe that the direct benefits of the proposed rule are 
best expressed in biological terms that can be weighed against the 
expected cost impacts of the rulemaking.
    Where data are available, the economic analysis does discuss and 
attempt to measure the net economic impacts of this rulemaking. For 
example, Chapter 2 discusses the reduction in net economic benefit to 
municipal and industrial water users that may occur with pumping 
restrictions. The analysis also discusses the fact that higher 
springflow levels are anticipated to contribute to river flows 
downstream of the aquifer, which will make more water available to 
municipalities, industries, and farmers who use river water. Whether 
the users will use the water to an economic benefit depends on a myriad 
of factors that are beyond the scope of the economic analysis; however, 
the analysis notes that increased springflows are likely to generate 
potentially significant ecological and/or recreational benefits.
    18. Comment: Section 1.34(c) of the EAA Act of 1993, as amended, 
notes that a ``holder of a permit for irrigation use may not lease more 
than 50 percent of the irrigation rights initially permitted. The 
user's remaining irrigation water rights must be used in accordance 
with the original permit and must pass with transfer of the irrigated 
land.'' Paragraph 83 of the economic analysis makes it unclear whether 
this restriction on irrigation transfers was considered in the 
analysis.
    Our Response: The analysis predicts that water users, when faced 
with lowered water permit availability, will sell or lease their water 
rights to higher-valued uses. The value of water in the planning area 
is assumed to rise faster than the profitability of irrigated crops, 
and thus agricultural water will be traded from agriculture to 
municipal and industrial use, as has been common in the western United 
States. Despite the current restriction on the sale and lease of 
irrigation rights in the Edwards Aquifer, the analysis assumes that the 
Edwards Aquifer Authority will be able to purchase and retire 
sufficient agricultural water rights for the purposes of maintaining 
aquifer levels in the future. While this assumption was implicit in the 
draft economic analysis, it is now stated explicitly in the final 
economic analysis.
    19. Comment: PCE 5 concludes that a gravel substrate is necessary 
for the Comal Springs riffle beetle because specimens were not found in 
Spring Run 4 where the substrate was primarily sand and not gravel. The 
Service has drawn this conclusion from a preliminary correlation 
reported in a study done by Bowles et al. (2003), and therefore, a 
definitive conclusion may inaccurately represent the findings. A number 
of abiotic and biotic factors, including flow rates, competition with 
other species, and other life-history traits may all have been 
contributing factors to the absence of the beetle in Spring Run 4.
    Our Response: In reviewing the best available information, we found 
that additional searches for the Comal Springs riffle beetle in Spring 
Run 3 and the western shoreline habitat of Landa Lake yielded results 
similar to those found by Bowles et al. (2003) with regard to the 
occurrence of this species on gravel, cobble, and rock substrates 
outside of areas with sedimentation or silt buildup (BIO-WEST 2002a, p. 
11). We included this additional reference within the discussion of PCE 
5. By referencing the survey results of Bowles et al. (2003), it was 
not our intention to imply that the Comal Springs riffle beetle could 
never be found in smaller sized substrates. Although we cannot 
determine the full scope of substrate habitat restrictions for the 
Comal Springs riffle beetle from the information provided in the above 
referenced reports, it does indicate that gravel, cobble, and rock 
substrates that are free of silt and sedimentation are essential 
features of the habitat for this species.
    20. Comment: ``Global warming'' is another impact to consider in 
protecting water quantity in the habitat of the Peck's cave amphipod, 
Comal Springs dryopid beetle, and Comal Springs riffle beetle. At least 
one science team has predicted higher temperatures, and thus, higher 
evaporation rates, and reduced rainfall for central Texas as a result 
of global warming.
    Our Response: We recognize that global climate change may affect 
global temperatures, and that this in turn can cause other climatic 
changes, such as changes in the amount and pattern of precipitation. 
However, the consequences of such changes to the Peck's cave amphipod, 
Comal Springs dryopid beetle, and Comal Springs riffle beetle are 
unknown. We therefore believe this issue to be outside the scope of the 
critical habitat designation for these species.

Summary of Changes From Proposed Rule

    Based upon our review of the peer review and public comments, 
economic analysis, and any new relevant information that may have 
become available since the publication of the proposal, we reevaluated 
our proposed critical habitat designation for the Peck's cave amphipod, 
Comal Springs dryopid beetle, and Comal Springs riffle beetle. We made 
no changes to the critical habitat designation as described in the 
proposed rule. Other than minor clarifications and incorporation of 
additional information on the species' biology, status, and threats, 
this final rule differs from the proposal by the following:
    (1) We modified the primary constituent elements for clarity and to 
reflect additional information received during the public comment 
period. Specifically we added, ``other compounds containing 
surfactants'' and ``pharmaceuticals and veterinary medicines,'' under 
the list of potential pollutants under PCE 1. Under PCE 3, we added the 
phrase, ``that allows for adequate spring flows'' to clarify the intent 
of the hydrologic regime. For PCE 4, we added, ``living plant material, 
algae, fungi, bacteria and other

[[Page 39253]]

microorganisms,'' to the list of potential food items.
    (2) We made technical corrections to some of the information found 
in the Primary Constituent Elements, Background, and Criteria Used to 
Identify Critical Habitat sections of this rule.

Critical Habitat

    Critical habitat is defined in section 3 of the Act as--(i) The 
specific areas within the geographical area occupied by a species, at 
the time it is listed in accordance with the Act, on which are found 
those physical or biological features (I) Essential to the conservation 
of the species and (II) that may require special management 
considerations or protection; and (ii) specific areas outside the 
geographical area occupied by a species at the time it is listed, upon 
a determination that such areas are essential for the conservation of 
the species. Conservation, as defined under section 3 of the Act means 
to use and the use of all methods and procedures that are necessary to 
bring any endangered species or threatened species to the point at 
which the measures provided under the Act are no longer necessary. Such 
methods and procedures include, but are not limited to, all activities 
associated with scientific resources management such as research, 
census, law enforcement, habitat acquisition and maintenance, 
propagation, live trapping, and transplantation, and, in the 
extraordinary case where population pressures within a given ecosystem 
cannot be otherwise relieved, may include regulated taking.
    Critical habitat receives protection under section 7 of the Act 
through the prohibition against destruction or adverse modification of 
critical habitat with regard to actions carried out, funded, or 
authorized by a Federal agency. Section 7 of the Act requires 
consultation on Federal actions that are likely to result in the 
destruction or adverse modification of critical habitat. The 
designation of critical habitat does not affect land ownership or 
establish a refuge, wilderness, reserve, preserve, or other 
conservation area. Such designation does not allow government or public 
access to private lands. Section 7 of the Act is a purely protective 
measure and does not require implementation of restoration, recovery, 
or enhancement measures.
    To be included in a critical habitat designation, the habitat 
within the area occupied by the species must first have features that 
are essential to the conservation of the species. Critical habitat 
designations identify, to the extent known using the best scientific 
data available, habitat areas that provide essential life cycle needs 
of the species (i.e., areas on which are found the primary constituent 
elements (PCEs), as defined at 50 CFR 424.12(b)).
    Occupied habitat may be included in critical habitat only if the 
essential features thereon may require special management or 
protection. Furthermore, when the best available scientific data do not 
demonstrate that the conservation needs of the species require 
additional areas, we cannot designate critical habitat in areas outside 
the geographical area occupied by the species at the time of listing. 
However, an area currently occupied by the species but not occupied at 
the time of listing, will likely be essential to the conservation of 
the species and, therefore, may be included in the critical habitat 
designation.
    The Service's Policy on Information Standards Under the Endangered 
Species 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 made by the Service represent the best 
scientific data available. They require Service biologists, to the 
extent consistent with the Act and with the use of the best scientific 
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, a primary source of 
information is generally the listing package for the species. 
Additional information sources may include the recovery plan for the 
species, articles in peer-reviewed journals, conservation plans 
developed by States and counties, scientific status surveys and 
studies, biological assessments, or other unpublished materials and 
expert opinion or personal knowledge. All information is used in 
accordance with the provisions of 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.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific and commercial data available. Habitat 
is often dynamic, and species may move from one area to another over 
time. Furthermore, we recognize that designation of critical habitat 
may not include all of the habitat areas that may eventually be 
determined to be necessary for the recovery of the species. For these 
reasons, critical habitat designations do not signal that habitat 
outside the designation is unimportant or may not be required for 
recovery.
    Areas that support populations, but are outside the critical 
habitat designation, 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 a different outcome.

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 designate as critical 
habitat, we consider those physical and biological features (known as 
primary constituent elements) that are essential to the conservation of 
the species, and within areas occupied by the species at the time of 
listing, that may require special management considerations or 
protection. These include, but are not limited to: (1) Space for 
individual and population growth, and for normal behavior; (2) food, 
water, air, light, minerals, or other nutritional or physiological 
requirements; (3) cover or shelter; (4) sites for breeding, 
reproduction, and rearing (or development) of offspring; and (5) 
habitats that are protected from disturbance or are representative of 
the historic geographical and ecological distributions of a species.
    The specific primary constituent elements required for the Peck's 
cave amphipod, Comal Springs dryopid beetle, and Comal Springs riffle 
beetle are derived from the biological needs of these species as 
described in the Background section of this final rule and in the 
December 18, 1997, final rule listing these species (62 FR 66295).
    Pursuant to the Act and its implementing regulations, we are 
required to identify the known physical

[[Page 39254]]

and biological features (PCEs) within the geographical area occupied at 
the time of listing that are essential to the conservation of the 
Peck's cave amphipod, Comal Springs dryopid beetle, and Comal Springs 
riffle beetle, which may require special management considerations or 
protections. All areas designated as critical habitat for Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle 
are occupied, within the species' historic geographic ranges, and 
contain sufficient PCEs to support at least one life history function.
    Based on our current knowledge of the life history, biology, and 
ecology of these species, and the habitat requirements for sustaining 
the essential life history functions of these species, we have 
determined that the Peck's cave amphipod, Comal Springs dryopid beetle, 
and Comal Springs riffle beetle require the PCEs described below. The 
PCEs apply to all three species unless otherwise noted.
    PCE 1. High-quality water with no or minimal levels of pollutants, 
such as soaps and detergents (Brown 1987, p. 261) and other compounds 
containing surfactants, heavy metals, pesticides, fertilizer nutrients, 
petroleum hydrocarbons, pharmaceuticals and veterinary medicines, and 
semi-volatile compounds, such as industrial cleaning agents, and 
including:
    (a) Low salinity with total dissolved solids that generally range 
from about 307 to 368 milligrams per liter (mg/L); and
    (b) Low turbidity that generally is less than 5 nephelometric 
(measurement of turbidity in a water sample by passing light through 
the sample and measuring the amount of the light that is deflected) 
turbidity units (NTUs).
    These spring-adapted aquatic species live in high-quality 
unpolluted groundwater and spring outflows that have low levels of 
salinity and turbidity. High-quality discharge water from springs and 
adjacent subterranean areas also help sustain habitat components, such 
as riparian vegetation, that are essential to the Peck's cave amphipod, 
Comal Springs dryopid beetle, and Comal Springs riffle beetle. The two 
beetle species are thought to require water with adequate levels of 
dissolved oxygen for respiration (Brown 1987, p. 260; Arsuffi 1993, p. 
18). Amphipods generally require relatively high concentrations of 
oxygen and may serve as an indicator of good water quality (Arsuffi 
1993, p. 15). While definitive studies on the limits of tolerance and 
preference for these aquatic invertebrates have not been completed, the 
aquatic invertebrates are exclusively found in aquatic habitats with 
constant temperature, low salinity, low turbidity, and extremely low 
levels of pollutants. In particular, respiration in the riffle beetle 
may be inhibited by pollutants such as soaps and detergents that can 
affect its respiratory mechanism (Brown 1987, p. 261). The dryopid 
beetle may also be affected by these particular pollutants, since this 
species shares a similar respiratory structure (Arsuffi 1993, p. 18). 
However, biological tolerances for this species are not understood due 
to its existence within a subterranean habitat.
    Based on available literature, we believe that the PCE for high 
water quality in the critical habitat for these species should have an 
approximate range of salinity of about 307 to 368 mg/L and a turbidity 
of less than 5 NTUs. Fahlquist and Slattery (1997, p. 3) reported a low 
salinity (as measured by total dissolved solids) as low as 307 mg/L at 
Comal Springs, and Slattery and Fahlquist (1997, p. 4) found that San 
Marcos Springs had a low salinity of 328 mg/L. The two springs also 
have a low turbidity of less than 5 NTUs (Fahlquist and Slattery 1997, 
p. 3; Slattery and Fahlquist 1997, p. 4). Brune (1975, p. 94) reported 
a salinity for Hueco Springs of 322 mg/L. The highest salinity (as 
determined by analysis of total dissolved solids) that we have found 
associated with any of these invertebrates was 368 mg/L, which was 
reported from Fern Bank Springs on April 28, 2005 (Texas Water 
Development Board 2006, p. 1).
    PCE 2. Aquifer water temperatures that range from approximately 68 
to 75 [deg]F (20 to 24 [deg]C).
    The three listed invertebrate species complete their life cycle 
functions within a relatively narrow temperature range; water 
temperatures outside of this range could be harmful to these 
invertebrates. The temperature of spring water emerging from the 
Edwards Aquifer at Comal Springs and San Marcos Springs ordinarily 
occurs within a narrow range of approximately 72 to 75 [deg]F (22 to 24 
[deg]C) (Fahlquist and Slattery 1997, pp. 3-4; Groeger et al. 1997, pp. 
282-283). Hueco Springs and Fern Bank Springs have temperature records 
of 68 to 71 [deg]F (20 to 22 [deg]C) (George 1952, p. 52; Brune 1975, 
p. 94; Texas Water Development Board 2006, p. 1).
    PCE 3. A hydrologic regime that allows for adequate spring flows 
that provide levels of dissolved oxygen in the approximate range of 4.0 
to 10.0 mg/L for respiration of the Comal Springs riffle beetle and 
Comal Springs dryopid beetle.
    Respiration in most beetle species belonging to the family Elmidae 
(which includes the Comal Springs riffle beetle) typically requires 
flowing waters highly saturated with dissolved oxygen (Brown 1987, p. 
260). As a consequence, riffle beetles are most commonly associated 
with flowing water that has shallow riffles (small waves) or rapids 
(Brown 1987, p. 253). Although there are not available data to support 
a correlation between minimum spring flows and survival or other 
sublethal, adverse effects of low or no spring flows on these species, 
there is information to indicate that availability and access to water 
at the spring sites are important factors in their respiration. For 
example, riffle beetles are known to be restricted to waters with high 
dissolved oxygen due to their reliance on a plastron (a thin sheet of 
air) that is held next to the underside of the body surface by a mass 
of minute, hydrophobic (tending to repel and not absorb water) hairs. 
The plastron functions as a gill by allowing oxygen to diffuse 
passively from water into the plastron and replace oxygen absorbed 
during respiration (Brown 1987, p. 260). Beetle species in the Elmidae 
family are generally limited to well-aerated water environments since 
gaseous exchange with a plastron can actually be reversed in oxygen-
depleted waters (Brown 1987, p. 260; Ward 1992, p. 130). The Comal 
Springs dryopid beetle also relies on a plastron for respiration, and 
this beetle species may also be affected by changes in oxygen levels 
caused by habitat modification (Arsuffi 1993, pp. 17-18).
    PCE 4. Food supply that includes detritus (decomposed materials), 
leaf litter, living plant material, algae, fungi, bacteria and other 
microorganisms, and decaying roots.
    Feeding ecology in the Elmidae family varies among species, but 
most riffle beetles, as larvae and adults, feed on algae and detritus 
scraped from the substrates within their habitat (Brown 1987, p. 262). 
Specific food requirements for each of the three invertebrate species 
are unknown. However, the Peck's cave amphipod and dryopid beetle are 
most commonly found in areas where plant roots are inundated or 
otherwise influenced by aquifer water. Potential food sources for all 
three species in these areas include detritus (decomposed materials), 
leaf litter, and decaying roots; however, it is possible that these 
species feed on bacteria and fungi associated with decaying plant 
material. Both beetle species may be detritivores (detritus-feeding 
animals) that consume detrital materials in spring-influenced riparian 
zones (Brown 1987, p. 262; Randy

[[Page 39255]]

Gibson 2006, pp. 1-2). The best information available indicates the 
Peck's cave amphipod is an omnivore (a species capable of consuming 
both animals and plants), which would enable the amphipod to exist as a 
scavenger or predator inside the aquifer in addition to using detritus 
in areas near spring outlets where plant roots interface with spring 
water (Gibson 2006, p. 1).
    Trees and shrubs in riparian areas adjacent to the spring system 
may provide plant growth necessary to maintain food sources such as 
decaying material for these invertebrates. Roots from trees and shrubs 
in proximity to spring outlets are most likely to penetrate underground 
down to the water pools, where these roots can serve as habitat for the 
amphipod and dryopid beetle. We believe relatively intact riparian 
areas with trees and shrubs may provide an important function within 
areas designated for critical habitat of the two subterranean species. 
According to patterns of plant canopies as determined from aerial 
photographs, trees and shrubs (and their root systems) are generally 
within 50 ft (15.2 m) of the edge of water in these spring systems.
    PCE 5. Bottom substrate in surface water habitat of the Comal 
Springs riffle beetle that is free of sand and silt, and is composed of 
gravel and cobble ranging in size between 0.3 to 5.0 inches (in) (8-128 
millimeters (mm)).
    Although Comal Springs riffle beetles occur in conjunction with a 
variety of bottom substrates in surface water habitat, Bowles et al. 
(2003, p. 372) found that these beetles mainly occurred in areas with 
gravel and cobble ranging between 0.3 to 5.0 in (8-128 mm). Collection 
efforts in areas of high sedimentation generally do not yield riffle 
beetles (Bowles et al. 2003, p. 376). Similarly, BIO-WEST (2002, p. 11) 
conducted surveys for the Comal Springs riffle beetle in the Comal 
system and found that individuals of this species were restricted to 
habitat areas that consisted of rocks and gravel. They also observed 
that riffle beetles were only found in areas that were largely silt-
free (BIO-WEST 2002, p.11).
    This designation is designed for the conservation of PCEs necessary 
to support the life history functions that were the basis for the 
proposal and the areas containing those PCEs. Because not all life 
history functions require all of the PCEs, not all of the designated 
critical habitat may contain all the PCEs.
    Units are designated based on sufficient PCEs being present to 
support at least one of each of the species' life history functions. 
Some units contain all PCEs and support multiple life processes, while 
some units contain only a portion of the PCEs necessary to support the 
species' particular use of that habitat. Where a subset of the PCEs is 
present at the time of designation, this rule protects those PCEs and 
thus the conservation function of the habitat.

Special Management Considerations or Protections

    When designating critical habitat, we assess whether the areas 
determined to be occupied at the time of listing contain the features 
essential to the conservation that may require special management 
considerations or protections. Primary threats to the spring systems 
designated as critical habitat for the three invertebrate species that 
may require special management are summarized in Table 2. The threats 
for individual springs vary according to the degree of urbanization and 
availability of aquifer source water, but possible threats generally 
include prolonged cessation of spring flows (in 1956, Comal Springs at 
New Braunfels did not flow from mid-June to November (U.S. Army Corps 
of Engineers 1965)) as a result of the loss of hydrological 
connectivity within the aquifer (e.g., groundwater pumping, excavation, 
concrete filling), pollutants (e.g., stormwater drainage, pesticide 
use), and non-native species (e.g., biological control, sport fish 
stocking). To address the threats affecting these three invertebrate 
species, certain special management actions may be required--for 
example, maintenance of sustainable groundwater use and subsurface 
flows, use of adequate buffers for water quality protection, selection 
of appropriate pesticides, and implementation of integrated pest 
management plans.

Criteria Used To Identify Critical Habitat

    As required by section 4(b)(1)(A) of the Act, we use the best 
scientific and commercial data available in determining areas that 
contain the features that are essential to the conservation of the 
Peck's cave amphipod, Comal Springs dryopid beetle, and Comal Springs 
riffle beetle.
    We reviewed available information that pertains to the presence and 
habitat requirements of these three invertebrate species, such as 
research published in peer-reviewed articles, data in reports submitted 
during section 7 consultations, contracted surveys, agency reports and 
databases, and aerial photographs. Information that has been reviewed 
includes, but is not limited to: Holsinger (1967), Bosse et al. (1988), 
Barr and Spangler (1992), Arsuffi (1993), Barr (1993), BIO-WEST (2001, 
2002a, 2002b, 2003, 2004), Bowles et al. (2003), Fries et al. (2004), 
and Krejca (2005). As part of the process, we also reviewed the overall 
approach to conservation of these species undertaken by local, State, 
and Federal agencies, and private and non-governmental organizations 
operating within the species' range since their listing in 1997.
    Peck's cave amphipod--The Peck's cave amphipod has been found in 
Comal Springs and Hueco Springs, which are both located in Comal 
County. While limited data have been collected on the extent to which 
this subterranean species exists below ground away from outlets of 
spring systems, other species within the genus Stygobromus are known to 
be widely distributed in groundwaters and cave systems (Holsinger 1972, 
p. 65). Although this species could possibly range throughout the 4-
mile (mi) (8-kilometer (km)) distance between the two habitat spring 
systems through the ``honeycomb'' pores and conduits of the Edwards 
Aquifer, it is not known to what extent below-ground connections 
between Comal Springs and Hueco Springs are inhabited by the amphipod. 
The only specific location information we have for this species 
regarding its distribution in the aquifer, aside from where they exit 
the aquifer via spring openings, is an observation of Peck's cave 
amphipods at the bottom of a well (Panther Canyon well) that is located 
approximately 360 ft (110 m) away from the head outlet of Spring Run 
No. 1 (as designated in Barr and Spangler 1992, Fig. 1 on p. 42) in the 
Comal Springs complex (Krejca 2005, p. 83).
    We are designating critical habitat for the Peck's cave amphipod in 
aquatic habitat associated with both Comal Springs and Hueco Springs. 
To include amphipod food sources in root/water interfaces around spring 
outlets, we also are designating an area consisting of a 50-ft (15.2-m) 
distance from spring outlets of both Comal Springs and Hueco Springs 
(including several satellite springs that are located between the main 
outlet of Hueco Springs and the Guadalupe River). We believe that this 
50-ft distance defines the lateral extent of critical habitat that 
contains PCEs necessary to provide for life functions of the Peck's 
cave amphipod with respect to roots that can penetrate into the 
aquifer. Based on the 50-ft distance, the areas designated for the 
amphipod critical habitat are about 38.1 ac (15.4 ha) at Comal Springs 
and 0.4 ac (0.2 ha) at Hueco Springs. The acreages were calculated with 
a computer-based Geographical Information System (GIS). Designated 
critical habitat does not

[[Page 39256]]

include areas where PCEs do not occur for this species, such as 
buildings, roads, sidewalks, campgrounds, and lawns. Where lakes are 
designated, critical habitat is only designated in a radius of 50 ft 
(15.2 m) around springs and does not include other areas of the lake 
bottom where springs do not occur.
    Comal Springs dryopid beetle--The Comal Springs dryopid beetle has 
been found in only two spring systems, Comal Springs and Fern Bank 
Springs, located in Comal and Hays Counties, respectively. The 
subterranean species is primarily collected near spring outlets (Barr 
and Spangler 1992, p. 41). While the extent to which the dryopid beetle 
inhabits subterranean areas away from spring outlets is unknown, this 
species does not swim and may be limited to relatively short ranges 
within the aquifer. In addition, immature stages of the species are 
thought to be terrestrial (Barr 1993, p. 56); however, they may also 
exist in spring outlets and in subterranean, air-filled chambers, such 
as caves (Barr and Spangler 1992, pp. 51-52). Barr and Spangler (1992, 
p. 41) collected larvae of the dryopid beetle near spring outlets of 
Comal Springs and believed that the larvae were associated with 
ceilings of spring orifices. Extension of the dryopid beetle into the 
aquifer may also be limited by the lack of food materials associated 
with decaying plant roots that occur near spring orifices.
    For critical habitat of the Comal Springs dryopid beetle, we are 
designating aquatic habitat and a 50-ft (15.2-m) distance from spring 
outlets of Comal Springs and Fern Bank Springs. The 50-ft (15.2-m) 
distance is based on evaluations of aerial photographs showing tree and 
shrub canopies occurring in proximity to spring outlets at both spring 
systems. These plant canopies reflect approximate distances where plant 
root systems interface with water flows of the two spring systems. 
Based on the 50-ft (15.2-m) distance, the area designated for dryopid 
beetle critical habitat at Comal Springs is about 38.1 ac (15.4 ha), 
and 1.4 ac (0.6 ha) at Fern Bank Springs. These acreages include 
occupied areas that contain PCEs necessary for life history functions 
of the Comal Springs dryopid beetle. The acreages were calculated with 
GIS. Designated critical habitat does not include areas where PCEs do 
not occur for this species, such as lawns, buildings, roads, parking 
lots, and sidewalks. Where lakes are designated, critical habitat is 
only designated in a radius of 50 ft (15.2 m) around springs and does 
not include other areas of the lake bottom where springs do not occur.
    Comal Springs riffle beetle--For the Comal Springs riffle beetle, 
habitat is primarily restricted to surface water in two impounded 
spring systems that are located within Comal and Hays Counties in 
central Texas. In Comal County, the aquatic beetle species is found in 
various spring outlets and seeps of Comal Springs that occur within the 
spring runs of Landa Lake and within Landa Lake itself, over a linear 
distance of about 0.9 mi (1.4 km). The species has also been found in 
outlets of San Marcos Springs in the upstream portion of Spring Lake in 
Hays County. However, populations of Comal Springs riffle beetles may 
exist elsewhere in Spring Lake since spring systems within the lake are 
interconnected, and sampling to date for the species within the lake 
has been limited.
    For critical habitat of the Comal Springs riffle beetle, we are 
designating an area that encompasses all of the spring outlets that are 
found within the same lake (excluding a slough (slack water) portion 
that lacks spring outlets). Apart from the slough portion, the 
approximate linear distance of Spring Lake at its greatest length is 
0.2 mi (0.3 km). We are designating about 19.8 ac (8.0 ha) of aquatic 
habitat in Landa Lake and about 10.5 ac (4.3 ha) of aquatic habitat in 
Spring Lake as critical habitat. These areas contain PCEs necessary for 
life-history functions of the Comal Springs riffle beetle. We did not 
include the 50-ft (15.2-m) lateral extent around springs because, 
unlike the other two species, the riffle beetle is believed to occur on 
the surface and not subterranean. The acreages were estimated by 
calculating the cross-hatched polygon area in two map figures of these 
lakes using GIS. Designated critical habitat does not include areas 
where PCEs do not occur for this species, such as lawns, buildings, 
roads, parking lots, and sidewalks.
    When determining critical habitat boundaries, we made every effort 
to avoid including within those boundaries of the maps contained within 
this final rule developed areas such as buildings, paved areas, and 
other structures that lack PCEs for the Peck's cave amphipod, Comal 
Springs dryopid beetle, or Comal Springs riffle beetle. These efforts 
included overlaying critical habitat boundaries onto aerial photos to 
determine the percentage of buildings, lawns, and paved areas that were 
located within the critical habitat designations. In the few instances 
that this occurred, these areas were excluded in the text of the 
critical habitat unit descriptions in the Critical Habitat Designation 
section of this final rule. The estimated acreages for these areas were 
so small (i.e., approximately 2 percent or less of the critical habitat 
units involved), it was not practical to exclude them from the GIS 
coordinates provided for the designated critical habitat units in this 
final rule. We believe that eliminating buildings, lawns, and paved 
areas in the text of the critical habitat descriptions was the most 
feasible means of excluding these areas from the designations and 
provided a clearer indication of the exclusions for the public. The 
scale of the maps prepared under the parameters for publication within 
the Code of Federal Regulations may not reflect the exclusion of such 
developed areas. Any such structures and the surface under them 
inadvertently left inside critical habitat boundaries shown on the maps 
of this final rule have been excluded by text in the final rule and are 
not designated as critical habitat. Therefore, Federal actions limited 
to these areas would not trigger section 7 consultation, unless they 
may affect the species or PCEs in adjacent critical habitat.
    We are designating critical habitat in areas that we have 
determined were occupied at the time of listing and contain sufficient 
PCEs to support life-history functions essential for the conservation 
of the species. Units of Comal Springs, Fern Bank Springs, Hueco 
Springs, and San Marcos Springs were designated based on sufficient 
PCEs being present to support at least one life process for the Peck's 
cave amphipod, Comal Springs dryopid beetle, and/or Comal Springs 
riffle beetle. A brief discussion of each area designated as critical 
habitat is provided in the unit descriptions below.

Critical Habitat Designation

    We are designating four units as critical habitat for the Peck's 
cave amphipod, Comal Springs dryopid beetle, and Comal Springs riffle 
beetle. The critical habitat areas described below constitute our best 
assessment of areas determined to be occupied at the time of listing, 
that contain the PCEs essential for the conservation of these species 
and may require special management, and those additional areas that 
were not known to be occupied at the time of listing but were found to 
be essential to the conservation of the Peck's cave amphipod, Comal 
Springs dryopid beetle, and Comal Springs riffle beetle. The four 
spring systems designated as critical habitat are: (1) The Comal 
Springs Unit, (2) the Fern Bank Springs Unit, (3) the Hueco Springs 
Unit, and (4) the San Marcos Springs Unit. Table 1 shows the occupied 
units,

[[Page 39257]]

as well as provides approximate areas (ac/ha) of these spring units 
that have been determined to meet the definition of critical habitat 
for the three listed invertebrates.

    Table 1.--Spring System Units, Occupancy, Distances From Spring Outlets, and Acreages of Critical Habitat
 Designated for the Peck's Cave Amphipod, Comal Springs Dryopid Beetle, and Comal Springs Riffle Beetle in Comal
                                            and Hays Counties, Texas
----------------------------------------------------------------------------------------------------------------
                                                                                   Distance from
                                 Spring systems                                   spring outlets    Designated
                                  designated as     Occupied at      Currently    for designated     critical
            Species             critical habitat      time of        occupied        critical         habitat
                                      areas           listing                       habitat  ft     acreage  ac
                                                                                        (m)            (ha)
----------------------------------------------------------------------------------------------------------------
Peck's cave amphipod..........  Comal Springs     Yes...........  Yes...........       50 (15.2)     38.1 (15.4)
                                 Unit.
                                Hueco Springs     Yes...........  Yes...........       50 (15.2)       0.4 (0.2)
                                 Unit.
Comal Springs dryopid beetle..  Comal Springs     Yes...........  Yes...........       50 (15.2)     38.1 (15.4)
                                 Unit.
                                Fern Bank         Yes...........  Yes...........       50 (15.2)       1.4 (0.6)
                                 Springs Unit.
Comal Springs riffle beetle...  Comal Springs     Yes...........  Yes...........           (\1\)      19.8 (8.0)
                                 Unit.
                                San Marcos        Yes...........  Yes...........           (\1\)     10.5 (4.3)
                                 Springs Unit.
----------------------------------------------------------------------------------------------------------------
\1\ Not applicable.

    Table 2 summarizes land ownership and threats for the four spring 
systems designated for critical habitat. Land ownership for these 
spring systems involves only the State of Texas, municipalities, and 
private landowners, and does not involve Federal or Tribal holdings. 
Comal Springs and San Marcos Springs are surrounded, respectively, by 
the cities of New Braunfels and San Marcos. Both Comal Springs and San 
Marcos Springs have been impounded with dams to form Landa Lake and 
Spring Lake, respectively. Possible threats to these urban spring 
systems include, but are not limited to, water withdrawals, pesticide 
use, and stormwater runoff of pollutants that have accumulated on 
impervious cover (paved driveways, parking lots, sidewalks, etc.) in 
urban areas. A thorough threats discussion is found in the December 18, 
1997, final rule listing these species (62 FR 66295).

    Table 2.--Ownership and Threats to Springs or Listed Species for
                         Critical Habitat Units
------------------------------------------------------------------------
                                  Ownership of
 Designated critical habitat   critical habitat by    Threats to spring
            units               listed species ac     system or listed
                                      (ha)                 species
------------------------------------------------------------------------
Comal Springs Unit, Comal     Peck's cave amphipod  Water withdrawals,
 County.                       State--19.8 (8.0)..   hazardous materials
                               Municipal--7.3        spills, pesticide
                               (3.0).                use, excavation/
                               Private--11.0 (4.5)   construction,
                                                     stormwater
                                                     pollutants,
                                                     invasive species,
                                                     and well
                                                     entrainment.
                              Comal Springs         ....................
                               dryopid beetle
                               State--19.8 (8.0)..
                               Municipal--7.3
                               (3.0).
                               Private--11.0 (4.5)
                              Comal Springs riffle  ....................
                               beetle
                               State--19.8 (8.0)..
Fern Bank Springs Unit, Hays  Comal Springs         Water withdrawals,
 County.                       dryopid beetle.       excavation/
                               Private--1.4 (0.6).   construction, and
                                                     pesticide use.
Hueco Springs Unit, Comal     Peck's cave amphipod  Water withdrawals,
 County.                       Private--0.4 (0.2).   hazardous materials
                                                     spills, pesticide
                                                     use, excavation/
                                                     construction,
                                                     stormwater
                                                     pollutants, and
                                                     well entrainment.
San Marcos Springs Unit,      Comal Springs riffle  Water withdrawals,
 Hays County.                  beetle.               hazardous materials
                               State--10.5 (4.3)..   spills, pesticide
                                                     use, excavation/
                                                     construction,
                                                     stormwater
                                                     pollutants, and
                                                     invasive species.
------------------------------------------------------------------------

    We present brief descriptions of all units and reasons why they 
meet the definition of critical habitat for Peck's cave amphipod, Comal 
Springs dryopid beetle, and Comal Springs riffle beetle below. Maps of 
the designated critical habitat units are provided in the Regulation 
Promulgation section of this rule.

Comal Springs Unit--Comal County, Texas

    The Comal Springs system provides habitat for all three listed 
invertebrate species, along with a federally listed fish, the 
endangered fountain darter (Etheostoma fonticola). No other critical 
habitat has been designated at this spring system. Comal Springs 
provides all of the PCEs necessary for conservation of the three 
invertebrate species. The spring system primarily occurs as a series of 
spring outlets that lie along the west shoreline of Landa Lake and 
within the lake itself. This nearly L-shaped lake is surrounded by the 
City of New Braunfels. Practically all of the spring outlets and spring 
runs associated with Comal Springs occur within the upper part of the 
lake above the confluence of Spring Run No. 1 with the lake. The land 
ownership of Comal Springs consists of private, municipal, and State 
holdings. The surface water and bottom of Landa Lake are State-owned. 
The City of New Braunfels owns approximately 40 percent of the land 
surface adjacent to the lake, and private landowners own approximately 
60 percent. Approximate acreages of surface land ownership within the 
designated critical habitat unit and

[[Page 39258]]

threats to the unit are shown in Table 2.
    Critical habitat for the three listed invertebrate species in the 
Comal Springs Unit is as follows:
    (1) Landa Lake (Comal Springs riffle beetle only)--aquatic habitat 
within the lake and outlying spring runs that occur from the confluence 
of Blieders Creek at the upstream end of Landa Lake down to the lake's 
lowermost point of confluence with Spring Run No. 1. The part of Landa 
Lake that lies below the confluence with Spring Run No. 1 down to the 
impounding dams at the downstream end of the lake is not included.
    (2) Aquatic habitat and shoreline areas of Landa Lake (Peck's cave 
amphipod and Comal Springs dryopid beetle only)--aquatic habitat within 
the lake and outlying spring runs that occur from the confluence of 
Blieders Creek at the upstream end of Landa Lake down to the lake's 
lowermost point of confluence with Spring Run No. 1. The part of Landa 
Lake that lies below the confluence with Spring Run No. 1 down to the 
impounding dams at the downstream end of the lake is not included. Land 
areas along the shoreline of Landa Lake and on small islands inside the 
lake that are within a 50-ft (15.2-m) distance from habitat spring 
outlets are included in the critical habitat. These shoreline areas in 
proximity to spring outlets provide trees and shrubs with roots that 
penetrate underground to serve as habitat for the Peck's cave amphipod 
and Comal Springs dryopid beetle. The critical habitat designated for 
the Peck's cave amphipod and Comal Springs dryopid beetle includes only 
aquatic and shoreline areas where PCEs exist for these two species and 
does not include areas where these features do not occur, such as 
lawns, buildings, roads, parking lots, and sidewalks. Where lakes are 
included, critical habitat is only designated for areas within a radius 
of 50 ft (15.2 m) around springs and does not include other areas of 
the lake bottom in areas where springs are absent.

Fern Bank Springs Unit--Hays County, Texas

    The Fern Bank Springs system provides habitat for only the Comal 
Springs dryopid beetle. No other critical habitat has been designated 
at this spring system. Fern Bank Springs provides all of the PCEs 
necessary for conservation of this species. The spring system is 
located approximately 0.2 mi (0.4 km) east of the junction of Sycamore 
Creek with the Blanco River in Hays County. This spring system occurs 
in a rural area and is relatively unaffected by current urban 
activities in the vicinity of the springs. It consists of a main outlet 
and a number of seep springs that occur at the base of a high bluff 
overlooking the Blanco River. This spring system is located entirely on 
land that is privately owned. Approximate acreages of land ownership 
encompassed within the designated critical habitat unit and threats to 
the unit are shown in Table 2.
    Critical habitat for the Comal Springs dryopid beetle in the Fern 
Bank Springs Unit as follows: Fern Bank Springs--aquatic habitat and 
land areas that are within a 50-ft (15.2-m) distance from spring 
outlets, including the main outlet of Fern Bank Springs and its 
associated seep springs. These land areas in proximity to spring 
outlets provide trees and shrubs with roots that penetrate underground 
to serve as habitat for the Comal Springs dryopid beetle. The critical 
habitat designated for the Comal Springs dryopid beetle includes only 
areas where PCEs exist for this species and does not include areas 
where these features do not occur, such as buildings, lawns, or paved 
areas.

Hueco Springs Unit--Comal County, Texas

    The Hueco Springs system provides habitat for only the Peck's cave 
amphipod. No other critical habitat has been designated at this spring 
system. Hueco Springs provides all of the PCEs necessary for 
conservation of this species. This spring system occurs in a rural area 
and is relatively unaffected by current urban activities in the 
vicinity of the springs. It has a main outlet that is located 
approximately 0.1 mi (0.2 km) south of the junction of Elm Creek with 
the Guadalupe River in Comal County. The main outlet itself lies 
approximately 500 ft (152 m) from the west bank of the Guadalupe River. 
Several satellite springs lie further south between the main outlet and 
the river. This spring system is located entirely on private land. The 
main outlet of Hueco Springs is located on undeveloped land, but the 
satellite springs occur within undeveloped areas of a privately owned 
campground. Approximate acreages of land ownership encompassed within 
the designated critical habitat unit and threats to the unit are 
indicated in Table 2.
    We designate critical habitat for the Peck's cave amphipod within 
the Hueco Springs Unit as follows:
    (1) Hueco Springs--aquatic habitat and land areas that are within 
50 ft (15.2 m) from habitat spring outlets, including the main outlet 
of Hueco Springs and its associated satellite springs. These land areas 
in proximity to spring outlets provide trees and shrubs with roots that 
penetrate underground to serve as habitat for the Peck's cave amphipod. 
The critical habitat designated for the Peck's cave amphipod includes 
only aquatic habitat and land areas where PCEs exist for this species. 
Areas consisting of buildings, roads, sidewalks, campgrounds, and lawns 
are excluded from this designation.

San Marcos Springs Unit--Hays County, Texas

    The San Marcos Springs system provides habitat only for the Comal 
Springs riffle beetle. However, the San Marcos Springs system provides 
habitat for five other federally listed species: (1) The endangered 
fountain darter, (2) the endangered San Marcos gambusia (Gambusia 
georgei), (3) the threatened San Marcos salamander (Eurycea nana), (4) 
the endangered Texas blind salamander (Eurycea (formerly Typhlomolge) 
rathbuni), and (5) endangered Texas wild-rice (Zizania texana) (Service 
1996, p. 6). However, the San Marcos gambusia has not been found in 
surveys during recent years and is presumed to be extinct (Edwards 
1999, p. 3). Critical habitat has been designated for the fountain 
darter, San Marcos gambusia, San Marcos salamander, and Texas wild-rice 
within Spring Lake and portions of the San Marcos River that lie 
downstream from Spring Lake (45 FR 47355, July 14, 1980). The San 
Marcos Springs unit provides all of the PCEs necessary for conservation 
of the Comal Springs riffle beetle. The spring system primarily occurs 
as a series of spring outlets that lie at the bottom of Spring Lake and 
along its shoreline. The lake is surrounded by the City of San Marcos 
in Hays County. The spring outlets associated with San Marcos Springs 
occur within the main part of the lake, excluding the slough portion 
that exists as an arm of the lake. The land ownership involving San 
Marcos Springs consists entirely of State holdings. The surface water 
and bottom of Spring Lake are State-owned; the State-affiliated Texas 
State University owns the adjacent land surface. Approximate acreages 
of surface land ownership in the designated critical habitat unit and 
threats to the unit are shown in Table 2.
    We designate critical habitat for the Comal Springs riffle beetle 
in the San Marcos Springs unit as: Spring Lake--aquatic habitat areas 
within the lake upstream of Spring Lake dam, with the exception of the 
slough portion of the lake upstream of its confluence with the main 
body.

[[Page 39259]]

Effects of Critical Habitat Designation

Section 7 Consultation

    Section 7 of the Act requires Federal agencies, including the 
Service, to ensure that actions they fund, authorize, or carry out are 
not likely to destroy or adversely modify critical habitat. In our 
regulations at 50 CFR 402.02, we define destruction or adverse 
modification as ``a direct or indirect alteration that appreciably 
diminishes the value of critical habitat for both the survival and 
recovery of a listed species. Such alterations include, but are not 
limited to, alterations adversely modifying any of those physical or 
biological features that were the basis for determining the habitat to 
be critical.'' However, recent decisions by the 5th and 9th Circuit 
Courts of Appeal have invalidated this definition. Pursuant to current 
national policy and the statutory provisions of the Act, destruction or 
adverse modification is determined on the basis of whether, with 
implementation of the proposed Federal action, the affected critical 
habitat would remain functional (or retain the current ability for the 
PCEs to be functionally established) to serve the intended conservation 
role for the species.
    Section 7(a) of the Act requires Federal agencies, including the 
Service, to evaluate their actions with respect to any species that is 
proposed or listed as endangered or threatened and with respect to its 
critical habitat, if any is proposed or designated. Regulations 
implementing this interagency cooperation provision of the Act are 
codified at 50 CFR part 402.
    If a species is listed or critical habitat is designated, section 
7(a)(2) of the Act 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 action may affect a listed species 
or its critical habitat, the responsible Federal agency (action agency) 
must enter into consultation with us. As a result of this consultation, 
compliance with the requirements of section 7(a)(2) will be documented 
through the Service's issuance of: (1) A concurrence letter for Federal 
actions that may affect, but are not likely to adversely affect, listed 
species or critical habitat; or (2) a biological opinion for Federal 
actions that may affect, but are likely to adversely affect, listed 
species or critical habitat.
    When we issue a biological opinion concluding that a project is 
likely to result in jeopardy to a listed species or 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 Director believes would avoid 
jeopardy to the listed species or 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 variable.
    Regulations at 50 CFR 402.16 require Federal agencies to reinitiate 
consultation on previously reviewed actions in instances where a new 
species is listed or critical habitat is subsequently designated that 
may be affected and the Federal agency has retained discretionary 
involvement or control over the action or such discretionary 
involvement or control is authorized by law. Consequently, some Federal 
agencies may request reinitiation of consultation with us on actions 
for which formal consultation has been completed, if those actions may 
affect subsequently listed species or designated critical habitat or 
adversely modify or destroy proposed critical habitat.
    Federal activities that may affect the Peck's cave amphipod, Comal 
Springs dryopid beetle, or Comal Springs riffle beetle or their 
designated critical habitat will require section 7 consultation under 
the Act. Activities on State, Tribal, local, or private lands requiring 
a Federal permit (such as a permit from the U.S. Army Corps of 
Engineers under section 404 of the Clean Water Act or a permit under 
section 10(a)(1)(B) of the Act from the Service) or involving some 
other Federal action (such as funding from the Federal Highway 
Administration, Federal Aviation Administration, or Federal Emergency 
Management Agency) will also be subject to the section 7 consultation 
process. Federal actions requiring section 7 consultation also include 
pumping of Edwards Aquifer water by Federal agencies, such as the 
Department of Defense or Service. Federal actions not affecting listed 
species or critical habitat, and actions on State, Tribal, local, or 
private lands that are not federally funded, authorized, or permitted, 
do not require section 7 consultations.

Application of the Jeopardy and Adverse Modification Standards for 
Actions Involving Effects to the Peck's Cave Amphipod, Comal Springs 
Dryopid Beetle, and Comal Springs Riffle Beetle and Their Critical 
Habitat

Jeopardy Standard
    The Service has applied an analytical framework for jeopardy 
analyses of Peck's cave amphipod, Comal Springs dryopid beetle, and 
Comal Springs riffle beetle that relies heavily on the importance of 
habitat conditions to the survival and recovery of these species. The 
section 7(a)(2) analysis is focused on the habitat conditions necessary 
to support them.
    The jeopardy analysis usually expresses the survival and recovery 
needs of the Peck's cave amphipod, Comal Springs dryopid beetle, and 
Comal Springs riffle beetle in a qualitative fashion without making 
distinctions between what is necessary for survival and what is 
necessary for recovery. Generally, if a proposed Federal action is 
incompatible with the viability of the affected species, inclusive of 
associated habitat conditions, a jeopardy finding is warranted because 
of the relationship of each core area population to the survival and 
recovery of the species as a whole.
Adverse Modification Standard
    For the reasons described in the Director's December 9, 2004, 
memorandum, the key factor related to the adverse modification 
determination is whether, with implementation of the proposed Federal 
action, the affected critical habitat would remain functional (or 
retain the current ability for the PCEs to be functionally established) 
to serve the intended conservation role for the species. Generally, the 
conservation role of critical habitat units for the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle 
is to have each unit support viable populations.
    Section 4(b)(8) of the Act requires us to briefly evaluate and 
describe in any proposed or final regulation that designates critical 
habitat those activities involving a Federal action that may destroy or 
adversely modify such habitat, or that may be affected by such 
designation. Activities that may destroy or adversely modify critical 
habitat may also jeopardize the continued existence of the species.
    Activities that may destroy or adversely modify critical habitat 
are

[[Page 39260]]

those that alter the PCEs to an extent that the conservation value of 
critical habitat for Peck's cave amphipod, Comal Springs dryopid 
beetle, and Comal Springs riffle beetle is appreciably reduced. 
Activities that, when carried out, funded, or authorized by a Federal 
agency, may affect critical habitat and, therefore, should result in 
consultation for these listed species include, but are not limited to:
    (1) Actions that can negatively affect the PCEs of the Peck's cave 
amphipod, Comal Springs dryopid beetle, or Comal Springs riffle beetle;
    (2) Activities that would significantly and detrimentally alter the 
water quality in any of the spring systems listed above and would 
thereby destroy or adversely modify the critical habitat for any of 
theses species. These activities include, but are not limited to, 
sedimentation from construction or release of chemical or biological 
pollutants into the surface water or connected groundwater at a point 
source or by dispersed release (non-point source); such activities 
could also alter water conditions to a point that negatively affects 
these invertebrate species;
    (3) Actions that change the existing and historic flow regimes and 
would thereby significantly and detrimentally alter the PCEs necessary 
for conservation of these species. Such activities could include, but 
are not limited to, water withdrawal, impoundment, and water 
diversions. These activities could eliminate or reduce the habitat 
necessary for the growth, reproduction, or survival of these 
invertebrate species; and
    (4) Actions that remove hydraulic connectivity of the aquifer and 
the spring areas where it exists and would thereby negatively affect 
the PCEs of the designated critical habitat of these species and the 
population dynamics of the species. Alteration of subsurface water 
flows through destruction of geologic features (for example, 
excavation) or creation of impediments to flow (for example, concrete 
filling), especially in proximity to spring outlets, could negatively 
alter the hydraulic connectivity necessary to sustain these species. It 
is necessary for subsurface habitat to remain intact with sufficient 
hydraulic connectivity of flow paths and conduits to ensure that PCEs 
(water quality, water quantity, and food supply) for the designated 
critical habitat remain adequate for all three listed invertebrates.
    Due in large part to the nature of the aquifer and spring systems, 
ongoing human activities that occur outside the designated critical 
habitat may threaten the physical and biological features of the 
designated critical habitat. While we are only designating critical 
habitat in occupied areas where PCEs exist and are in need of special 
management (i.e., areas meeting the Service's criteria for defining 
critical habitat), consultation may also be needed outside of 
designated areas in order to avoid adverse modification of the PCEs 
within the designation. Federal activities outside of critical habitat 
(such as groundwater pumping, pollution, issuance of a section 
10(a)(1)(B) permit, highway construction, etc.) are subject to review 
under section 7 of the Act if they may affect these species or 
adversely affect their critical habitat.
    We consider all of the units designated as critical habitat to 
contain features essential to the conservation of the Peck's cave 
amphipod, Comal Springs dryopid beetle, or Comal Springs riffle beetle. 
All units are within the geographic range of the species, all were 
occupied by the species at the time of listing (based on observations 
made within the last 9 years), and are likely to be used by these 
listed invertebrates. Federal agencies already consult with us on 
activities in areas currently occupied by these listed invertebrates, 
or if the species may be affected by the action, to ensure that their 
actions do not jeopardize the continued existence of the Peck's cave 
amphipod, Comal Springs dryopid beetle, or Comal Springs riffle beetle.
Application of Section 4(a)(3) of the Act--Approved Integrated Natural 
Resource Management Plans
    The Sikes Act Improvement Act of 1997 (Sikes Act) (16 U.S.C. 670a) 
required each military installation that includes land and water 
suitable for the conservation and management of natural resources to 
complete, by November 17, 2001, an Integrated Natural Resource 
Management Plan (INRMP). An INRMP integrates implementation of the 
military mission of the installation with stewardship of the natural 
resources found on the base.
    The National Defense Authorization Act for Fiscal Year 2004 (Pub. 
L. 108-136) amended the Act to limit areas eligible for designation as 
critical habitat. Specifically, section 4(a)(3)(B)(i) of the Act (16 
U.S.C. 1533(a)(3)(B)(i)) now provides: The Secretary shall not 
designate as critical habitat any lands or other geographical areas 
owned or controlled by the Department of Defense, or designated for its 
use, that are subject to an integrated natural resources management 
plan prepared under section 101 of the Sikes Act (16 U.S.C. 670a), if 
the Secretary determines in writing that such plan provides a benefit 
to the species for which critical habitat is proposed for designation.
    There are no Department of Defense lands within the designated 
critical habitat that have completed an INRMP.
Application of Section 4(b)(2) of the Act
    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, national 
security impact, and any other relevant impact, of specifying any 
particular area as critical habitat. The Secretary may exclude an area 
from critical habitat if he determines that the benefits of such 
exclusion outweigh the benefits of specifying such area as part of the 
critical habitat, unless he determines, based on the best scientific 
data available, that the failure to designate such area as critical 
habitat will result in the extinction of the species. In making that 
determination, the Secretary is afforded broad discretion, and the 
Congressional record is clear that, in making a determination under the 
section, the Secretary has discretion as to which factors and how much 
weight will be given to any factor.
    Under section 4(b)(2), in considering whether to exclude a 
particular area from the designation, we must identify the benefits of 
including the area in the designation, identify the benefits of 
excluding the area from the designation, determine whether the benefits 
of exclusion outweigh the benefits of inclusion. If an exclusion is 
contemplated, then we must determine whether excluding the area would 
result in the extinction of the species. In the following sections, we 
address a number of general issues that are relevant to the exclusions 
we considered.
    Pursuant to section 4(b)(2) of the Act, we must consider relevant 
impacts in addition to economic ones. We determined that the lands 
within the designation of critical habitat for the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle 
are not owned or managed by the Department of Defense; there are 
currently no habitat conservation plans for the Peck's cave amphipod, 
Comal Springs dryopid beetle, and Comal Springs riffle beetle; and the 
designation does not include any Tribal lands or trust resources.
    We have considered a number of programs that exist at the State and 
local levels (e.g., EAA and Texas Commission for Environmental Quality) 
to protect the Edwards Aquifer and manage spring flows. As a result of 
a ruling in a 1991 court case (Sierra Club v. Secretary of the 
Interior, No. MO-91-CA-069), we

[[Page 39261]]

identified minimum spring flows from Comal and San Marcos springs 
likely to cause take, jeopardy, and adverse modification of critical 
habitat for other listed aquatic species. As a result of the Sierra 
Club lawsuit, the State legislature created the EAA through Senate Bill 
1477 to regulate groundwater withdrawals. The EAA has issued withdrawal 
permits and created drought response plans that help protect the PCEs 
related to water quantity and temperature. The EAA has prepared a draft 
Habitat Conservation Plan (HCP) to provide for water quantity in the 
aquifer and protect spring dependent species. If finalized and 
permitted, the HCP is expected to help protect the aquifer. However, at 
this time the HCP has not been completed and the EAA is continuing to 
develop aquifer management strategies to permit appropriate pumping 
levels and conserve downstream spring flows. The full effects of future 
pumping strategies on spring flows remain uncertain and do not allow us 
to exclude any areas from critical habitat based on the benefits of the 
Edwards Aquifer management.
    Other programs that provide some aquifer protection are Edwards 
Aquifer Rules and Phase I optional water quality measures of the Texas 
Commission on Environmental Quality (TCEQ). The Edwards Aquifer Rules 
provide protection for drinking water, and the Phase I measures provide 
protection for fountain darter, Texas wild-rice, San Marcos salamander, 
and San Marcos gambusia. The Edwards Aquifer Rules protect water 
quality by reducing pollutant loading through the implementation of 
best management practices that can help prevent degradation of 
groundwater. The Phase I optional water quality measures include 
enhanced best management practices that protect sensitive karst 
features. These measures also contain other protective actions that can 
be applied to many types of new projects. The Edwards Aquifer Rules and 
Phase I optional measures provide some benefits for the three Comal 
Springs invertebrates. However, the Phase I optional measures are not 
mandated for every project. Therefore we have considered excluding but 
have not excluded any lands from this designation based on the 
potential benefits from these planned or existing aquifer and water 
quality management initiatives.
    We anticipate no impact to national security, Tribal lands, 
partnerships, or habitat conservation plans from this critical habitat 
designation. Based on the best available information, including the 
prepared economic analysis, we believe that all of these units contain 
the features that are essential for the conservation of the species. 
Our economic analysis does not indicate any areas within the critical 
habitat designation will bear a disproportionate cost of the 
designation. Therefore, we have found no areas for which the benefits 
of exclusion outweigh the benefits of inclusion, and so have not 
excluded any areas from this designation of critical habitat for the 
Peck's cave amphipod, Comal Springs dryopid beetle, and Comal Springs 
riffle beetle based on economic impacts. As such, we have considered 
but not excluded any lands from this designation based on the potential 
impacts to economic factors.

Economics

    Section 4(b)(2) of the Act requires us to designate critical 
habitat on the basis of the best scientific information available and 
to consider the economic and other relevant impacts of designating a 
particular area as critical habitat. 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 concerned.
    Following the publication of the proposed critical habitat 
designation, we conducted an economic analysis to estimate the 
potential economic effect of the designation. The draft analysis was 
made available for public review on March 16, 2007 (72 FR 12585). We 
accepted comments on the draft analysis until April 16, 2007.
    The primary purpose of the economic analysis is to estimate the 
potential economic impacts associated with the conservation of the 
Peck's cave amphipod, Comal Springs dryopid beetle, and Comal Springs 
riffle beetle. This economic analysis considers the economic efficiency 
effects that may result from the designation, including habitat 
protections that may be co-extensive with the listing of the species. 
It also addresses distribution of impacts, including an assessment of 
the potential effects on small entities and the energy industry. This 
information can be used by the Secretary to assess whether the effects 
of the designation might unduly burden a particular group or economic 
sector.
    This analysis focuses on the direct and indirect costs of the rule. 
However, economic impacts to land use activities can exist in the 
absence of critical habitat. These impacts may result from, for 
example, section 7 consultations under the jeopardy standard, local 
zoning laws, State and natural resource laws, and enforceable 
management plans and best management practices applied by other State 
and Federal agencies.
    Under scenarios 1 and 2 in the draft economic analysis, impacts 
associated with water use changes comprised the vast majority, or 
between 91 and 99 percent, of the total quantified impacts in the areas 
we proposed for designation. Economic impacts were based on the total 
permitted withdrawals from the Edwards Aquifer that are planned to be 
reduced in part to provide spring flows that were identified in a 1993 
lawsuit concerning five endangered species in the Edwards Aquifer that 
share habitat with the Peck's cave amphipod, Comal Springs dryopid 
beetle, and Comal Springs riffle beetle. The analysis considered that 
as soon as 2008, total permitted water withdrawals in the Edwards 
Aquifer may be further limited from the present 549,000 acre-feet per 
year to 400,000 acre-feet per year (scenario 1). It is also possible 
that, in dry years, additional restrictions may be imposed that will 
further limit aquifer withdrawals to 340,000 acre-feet (scenario 2). 
The draft economic analysis examined social welfare and regional 
economic impacts that could result from these limits to water 
withdrawals in the aquifer. It should be noted that the majority of 
economic impacts quantified in the draft economic analysis are jointly 
caused by eight endangered species, including the Peck's cave amphipod, 
Comal Springs dryopid beetle, and Comal Springs riffle beetle. Because 
all of these species reside in the same habitat, separating future 
impacts of the Peck's cave amphipod, Comal Springs dryopid beetle, and 
Comal Springs riffle beetle from those of the other listed species in 
the aquifer was not attempted.
    We estimated costs related to conservation activities for the area 
proposed for designation of critical habitat for the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle 
under sections 4, 7, and 10 of the Act to be approximately $24.5 
million over the next 20 years under scenario 1, or $154.3 million 
under scenario 2 in undiscounted dollars (annualized dollars are 
estimated to be $1.2 million under scenario 1 and $7.7 million under 
scenario 2). Future economic impacts associated with conservation 
activities in areas designated as critical habitat at a 3 percent 
discount rate are estimated to be $18 million over the next 20 years

[[Page 39262]]

under scenario 1, or $113 million under scenario 2 (annualized dollars 
are estimated to be $1.2 million under scenario 1 and $7.6 million 
under scenario 2). Future economic impacts associated with conservation 
efforts in areas proposed as critical habitat at a 7 percent discount 
rate were estimated to be $12.5 million over the next 20 years under 
scenario 1, or $78.5 million under scenario 2 (annualized dollars are 
estimated to be $1.3 million under scenario 1 and $7.4 million under 
scenario 2). No areas were excluded from this designation as a result 
of the economic analysis. The economic analysis did not consider recent 
changes to the Edwards Aquifer Authority passed by the Texas 
Legislature in May 2007 (Senate Bill 3).
    A copy of the final economic analysis with supporting documents may 
be obtained by contacting U.S. Fish and Wildlife Service, Branch of 
Endangered Species (see FOR FURTHER INFORMATION CONTACT) or by download 
from the Internet at http://www.fws.gov/southwest/es/Library/.


Required Determinations

Regulatory Planning and Review

    In accordance with Executive Order (E.O.) 12866, this document is a 
significant rule in that it may raise novel legal and policy issues, 
but will not have an annual effect on the economy of $100 million or 
more or affect the economy in a material way. Due to the tight timeline 
for publication in the Federal Register, the Office of Management and 
Budget (OMB) has not formally reviewed this rule. As explained above, 
we prepared an economic analysis of this action. We used this analysis 
to meet the requirement of section 4(b)(2) of the Act to determine the 
economic consequences of designating the specific areas as critical 
habitat. We also used it to help determine whether to exclude any area 
from critical habitat, as provided for under section 4(b)(2) of the 
Act, if we determine that the benefits of such exclusion outweigh the 
benefits of specifying an area as part of the critical habitat, unless 
we determine, based on the best scientific data available, that the 
failure to designate such an area as critical habitat will result in 
the extinction of the species.

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

    Under the Regulatory Flexibility Act (RFA) (as amended by the Small 
Business Regulatory Enforcement Fairness Act (SBREFA) of 1996), 
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 (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. The SBREFA amended the RFA to 
require Federal agencies to provide a statement of factual basis for 
certifying that the rule will not have a significant economic impact on 
a substantial number of small entities. The SBREFA also amended the RFA 
to require a certification statement.
    Small entities include small organizations, such as independent 
nonprofit organizations; small governmental jurisdictions, including 
school boards and city and town governments that serve fewer than 
50,000 residents; as well as small businesses. 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 consider the types of 
activities that might trigger regulatory impacts under this rule, as 
well as the 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.
    To determine if the rule could significantly affect a substantial 
number of small entities, we consider the number of small entities 
affected within particular types of economic activities (such as 
housing development, grazing, oil and gas production, timber 
harvesting). We apply the ``substantial number'' test individually to 
each industry to determine if certification is appropriate. However, 
the SBREFA does not explicitly define ``substantial number'' or 
``significant economic impact.'' Consequently, to assess whether a 
``substantial number'' of small entities is affected by this 
designation, this analysis considers the relative number of small 
entities likely to be impacted in an area. In some circumstances, 
especially with critical habitat designations of limited extent, we may 
aggregate across all industries and consider whether the total number 
of small entities affected is substantial. In estimating the number of 
small entities potentially affected, we also consider whether their 
activities have any Federal involvement.
    Designation of critical habitat only affects activities conducted, 
funded, or permitted by Federal agencies. Some kinds of activities are 
unlikely to have any Federal involvement and so will not be affected by 
critical habitat designation. In areas where the species is present, 
Federal agencies already are required to consult with us under section 
7 of the Act on activities they fund, permit, or implement that may 
affect the Peck's cave amphipod, Comal Springs dryopid beetle, and 
Comal Springs riffle beetle. Federal agencies also must consult with us 
if their activities may affect critical habitat. Designation of 
critical habitat, therefore, could result in an additional economic 
impact on small entities due to the requirement to reinitiate 
consultation for ongoing Federal activities.
    The draft economic analysis examined the potential for Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle 
conservation efforts to affect small entities. This analysis was based 
on the estimated impacts associated with the proposed critical habitat 
designation and evaluated the potential for economic impacts related to 
water use for agricultural activities, construction or development, and 
aquatic restoration. Aquatic restoration activities were not 
anticipated to affect small entities, as these activities will be 
carried out by a Federal agency (U.S. Army Corps of Engineers). 
Accordingly, the small business analysis focused on economic impacts 
resulting from potential water use changes for agricultural activities 
and construction or development activities. Future restrictions on 
groundwater pumping are expected to cause irrigated crop acreage to 
shift to dryland production. Under Scenario 1, where future groundwater 
pumping is restricted to 400,000 acre-feet per year, approximately 
33,000 acres of irrigated cropland are expected to shift to dryland 
production, and 507 farms are likely to experience a reduction in 
output valued between $8,000 and $44,000. Under Scenario 2, where 
future groundwater pumping is restricted to 340,000 acre-feet per year, 
approximately 35,000 acres of irrigated cropland are expected to shift 
to dryland production, and 532 farms are likely to experience a 
reduction in

[[Page 39263]]

output valued between $9,000 and $45,000. However, these costs are 
associated with the conservation of the species, and may result from 
desirable management, but not necessarily management that can be 
required under the Act. For those development projects likely to be 
undertaken by a small entity, Peck's cave amphipod, Comal Springs 
dryopid beetle, and Comal Springs riffle beetle conservation costs are 
estimated to be between $1,340 and $1,710. Assuming the annual revenues 
of an average small developer are $18.0 million, the average annualized 
cost per project is about 0.1 percent of typical annual sales.
    In general, two different mechanisms in section 7 consultations 
could lead to additional regulatory requirements for the approximately 
four small businesses, on average, that may be required to consult with 
us each year regarding their project's impact on the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle beetle 
and its habitat. First, if we conclude, in a biological opinion, that a 
proposed action is likely to jeopardize the continued existence of a 
species or adversely modify its critical habitat, we can offer 
``reasonable and prudent alternatives.'' Reasonable and prudent 
alternatives are alternative actions that can be implemented in a 
manner consistent with the scope of the Federal agency's legal 
authority and jurisdiction, that are economically and technologically 
feasible, and that would avoid jeopardizing the continued existence of 
listed species or result in adverse modification of critical habitat. A 
Federal agency and an applicant may elect to implement a reasonable and 
prudent alternative associated with a biological opinion that has found 
jeopardy or adverse modification of critical habitat. An agency or 
applicant could alternatively choose to seek an exemption from the 
requirements of the Act or proceed without implementing the reasonable 
and prudent alternative. However, unless an exemption were obtained, 
the Federal agency or applicant would be at risk of violating section 
7(a)(2) of the Act if it chose to proceed without implementing the 
reasonable and prudent alternatives.
    Second, if we find that a proposed action is not likely to 
jeopardize the continued existence of a listed animal or plant species, 
we may identify reasonable and prudent measures designed to minimize 
the amount or extent of take and require the Federal agency or 
applicant to implement such measures through non-discretionary terms 
and conditions. We may also identify discretionary conservation 
recommendations designed to minimize or avoid the adverse effects of a 
proposed action on listed species or critical habitat, help implement 
recovery plans, or to develop information that could contribute to the 
recovery of the species.
    Based on our experience with consultations pursuant to section 7 of 
the Act for all listed species, virtually all projects--including those 
that, in their initial proposed form, would result in jeopardy or 
adverse modification determinations in section 7 consultations--can be 
implemented successfully with, at most, the adoption of reasonable and 
prudent alternatives. These measures, by definition, must be 
economically feasible and within the scope of authority of the Federal 
agency involved in the consultation. We can only describe the general 
kinds of actions that may be identified in future reasonable and 
prudent alternatives. These are based on our understanding of the needs 
of the species and the threats it faces, as described in the final 
listing rule and this critical habitat designation. Within the final 
critical habitat units, the types of Federal actions or authorized 
activities that we have identified as potential concerns are:
    (1) Regulation of activities affecting waters of the United States 
by the U.S. Army Corps of Engineers under section 404 of the Clean 
Water Act;
    (2) Regulation of water flows, damming, diversion, and 
channelization implemented or licensed by Federal agencies;
    (3) Activities that may lead to storm water runoff that are 
regulated under the National Pollution Discharge Elimination System of 
the Clean Water Act by the Environmental Protection Agency;
    (4) Activities authorized, carried out, or funded by any Federal 
agency that may result in point source storm water pollutant 
discharges, including excavation, site development, construction, and 
other surface disturbing activities;
    (5) Activities authorized, carried out, or funded by the Federal 
Highway Administration that could lead to the introduction of 
pollutants into receiving waters from highway runoff; and
    (6) Activities authorized, carried out, or funded by any Federal 
agency that could result in a reduction of groundwater supplies that 
support the Peck's cave amphipod, Comal Springs dryopid beetle, and 
Comal Springs riffle beetle.
    It is likely that a developer or other project proponent could 
modify a project or take measures to protect the Peck's cave amphipod, 
Comal Springs dryopid beetle, and Comal Springs riffle beetle. The 
kinds of actions that may be included if future reasonable and prudent 
alternatives become necessary include conservation set-asides, 
management of competing nonnative species, restoration of degraded 
habitat, and regular monitoring. These are based on our understanding 
of the needs of the species and the threats it faces, as described in 
the final listing rule and proposed critical habitat designation. These 
measures are not likely to result in a significant economic impact to 
project proponents.
    In summary, we have considered whether this would result in a 
significant economic effect on a substantial number of small entities. 
We have determined, for the above reasons and based on currently 
available information, that it is not likely to affect a substantial 
number of small entities. Federal involvement, and thus section 7 
consultations, would be limited to a subset of the area designated. The 
most likely Federal involvement could include actions needing a section 
404 permit under the Clean Water Act, actions receiving Federal Highway 
Administration funding, and actions needing a section 10(a)(1)(B) 
permit under the Endangered Species Act of 1973, as amended. A 
regulatory flexibility analysis is not required.

Small Business Regulatory Enforcement Fairness Act (5 U.S.C. 801 et 
seq.)

    Under SBREFA, this rule is not a major rule. Our detailed 
assessment of the economic effects of this designation is described in 
the economic analysis. Based on the effects identified in the economic 
analysis, we believe that this rule will not have an annual effect on 
the economy of $100 million or more, will not cause a major increase in 
costs or prices for consumers, and will not have significant adverse 
effects on competition, employment, investment, productivity, 
innovation, or the ability of U.S.-based enterprises to compete with 
foreign-based enterprises. Refer to the final economic analysis for a 
discussion of the effects of this determination.

Executive Order 13211

    On May 18, 2001, the President issued Executive Order 13211 
(Actions Concerning Regulations That Significantly Affect Energy 
Supply, Distribution, or Use) on regulations that significantly affect 
energy supply, distribution, and use. Executive Order 13211 requires 
agencies to prepare Statements of Energy Effects when undertaking 
certain actions. This final rule to designated critical habitat for the

[[Page 39264]]

Peck's cave amphipod, Comal Springs dryopid beetle, and Comal Springs 
riffle beetle is not expected to significantly affect energy supplies, 
distribution, or use. Therefore, this action is not a significant 
energy action, and no Statement of Energy Effects is required.

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

    In accordance with the Unfunded Mandates Reform Act (2 U.S.C. 1501 
et seq.), we make 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 because it will not produce a Federal mandate 
of $100 million or greater in any year; that is, it is not a 
``significant regulatory action'' under the Unfunded Mandates Reform 
Act. The designation of critical habitat imposes no obligations on 
State or local governments. As such, a Small Government Agency Plan is 
not required.

Takings

    In accordance with Executive Order 12630 (``Government Actions and 
Interference with Constitutionally Protected Private Property 
Rights''), we have analyzed the potential takings implications of 
designating 38.5 ac (15.6 ha) of lands in Comal County, Texas, as 
critical habitat for the Peck's cave amphipod, 39.5 ac (16.0 ha) of 
lands in Comal and Hays Counties, Texas, as critical habitat for the 
Comal Springs dryopid beetle, and 30.3 ac (12.3 ha) of lands in Comal 
and Hays counties, Texas, as critical habitat for the Comal Springs 
riffle beetle in a takings implication assessment. The takings 
implications assessment concludes that this final designation of 
critical habitat does not pose significant takings implications for 
lands within or affected by the designation.

Federalism

    In accordance with Executive Order 13132 (Federalism), the rule 
does not have significant Federalism effects. A Federalism assessment 
is not required. In keeping with the Department of the Interior and 
Department of Commerce policy, we requested information from, and 
coordinated development of, this final critical habitat designation 
with appropriate State resource agencies in Texas. The designation may 
have some benefit to these governments in that the areas that contain 
the features essential to the conservation of the species are more 
clearly defined, and the primary constituent elements of the habitat 
necessary to the conservation of the species are specifically 
identified. While making this definition and identification does not 
alter where and what federally sponsored activities may occur, it may 
assist these local governments in long-range planning (rather than 
waiting for case-by-case section 7 consultations to occur).

Civil Justice Reform

    In accordance with Executive Order 12988 (Civil Justice Reform), 
the Office of the Solicitor has determined that the rule does not 
unduly burden the judicial system and 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 Endangered Species 
Act. This final rule uses standard property descriptions and identifies 
the primary constituent elements within the designated areas to assist 
the public in understanding the habitat needs of the Peck's cave 
amphipod, Comal Springs dryopid beetle, and Comal Springs riffle 
beetle.

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

    This rule does not contain any new collections of information that 
require approval by OMB under the Paperwork Reduction Act. This rule 
will not impose recordkeeping or reporting requirements on State or 
local governments, individuals, businesses, or organizations. 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 (NEPA) (42 U.S.C. 4321 et seq.)

    It is our position that, outside the jurisdiction of the Tenth 
Federal Circuit, we do not need to prepare environmental analyses as 
defined by NEPA in connection with designating critical habitat under 
the Endangered Species Act of 1973, as amended. 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 (Douglas County v. Babbitt, 48 F.3d 1495 (9th Cir. 
Ore. 1995), cert. denied 516 U.S. 1042 (1996)).

Government-to-Government Relationship With Tribes

    In accordance with the President's memorandum of April 29, 1994, 
``Government-to-Government Relations with Native American Tribal 
Governments'' (59 FR 22951), Executive

[[Page 39265]]

Order 13175, and the Department of Interior's manual at 512 DM 2, we 
readily acknowledge our responsibility to communicate meaningfully with 
recognized Federal Tribes on a government-to-government basis. In 
accordance with Secretarial Order 3206 of June 5, 1997, ``American 
Indian Tribal Rights, Federal--Tribal Trust Responsibilities, and the 
Endangered Species Act,'' we readily acknowledge our responsibilities 
to work directly with tribes in developing programs for healthy 
ecosystems, to acknowledge that tribal lands are not subject to the 
same controls as Federal public lands, to remain sensitive to Indian 
culture, and to make information available to tribes. We have 
determined that there are no Tribal lands occupied at the time of 
listing that contain the features essential for the conservation and no 
Tribal lands that are unoccupied areas that are essential for the 
conservation of the Peck's cave amphipod, Comal Springs dryopid beetle, 
and Comal Springs riffle beetle. Therefore, we have not designated 
critical habitat for the Peck's cave amphipod, Comal Springs dryopid 
beetle, and Comal Springs riffle beetle on Tribal lands.

References Cited

    A complete list of all references cited in this rulemaking is 
available upon request from the Field Supervisor, Austin Ecological 
Services Office (see FOR FURTHER INFORMATION CONTACT).

Author(s)

    The primary authors of this final rule are staff of the Ecological 
Services Office in Austin, Texas (see FOR FURTHER INFORMATION CONTACT).

List of Subjects in 50 CFR Part 17

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

Regulation Promulgation

0
Accordingly, we amend part 17, subchapter B of chapter I, title 50 of 
the Code of Federal Regulations, as set forth below:

PART 17--[AMENDED]

0
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.


0
2. Amend Sec.  17.11(h), the List of Endangered and Threatened 
Wildlife, as follows:
0
a. Under ``INSECTS,'' revise the entries for ``Beetle, Comal Springs 
dryopid'' and ``Beetle, Comal Springs riffle'' to read as set forth 
below; and
0
b. Under ``CRUSTACEANS,'' revise the entry for ``Amphipod, Peck's 
cave'' to read as set forth below.


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
--------------------------------------------------------------------------------------------------------------------------------------------------------

                                                                      * * * * * * *
              INSECTS

                                                                      * * * * * * *
Beetle, Comal Springs dryopid......  Stygoparnus comalensis  U.S.A. (TX)...........  NA                 E                      629   17.95(i)         NA
Beetle, Comal Springs riffle.......  Heterelmis comalensis.  U.S.A. (TX)...........  NA                 E                      629   17.95(i)         NA

                                                                      * * * * * * *
            CRUSTACEANS

                                                                      * * * * * * *
Amphipod, Peck's cave..............  Stygobromus             U.S.A. (TX)...........  NA                 E                      629   17.95(h)         NA
                                      (=Stygonectes) Pecki.

                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------


0
3. Amend Sec.  17.95 as follows:
0
a. In paragraph (h), add an entry for ``Peck's cave amphipod 
(Stygobromus pecki)'', in the same alphabetical order in which the 
species appears in the table at 50 CFR 17.11(h), to read as set forth 
below; and
0
b. In paragraph (i), add entries for ``Comal Springs dryopid beetle 
(Stygoparnus comalensis)'' and ``Comal Springs riffle beetle 
(Heterelmis comalensis)'', in the same alphabetical order in which 
these species appear in the table at 50 CFR 17.11(h), to read as set 
forth below.


Sec.  17.95  Critical habitat--fish and wildlife.

* * * * *
    (h) Crustaceans.
* * * * *
    Peck's cave amphipod (Stygobromus pecki).
    (1) Critical habitat units are depicted for Comal County, Texas, on 
the maps below.
    (2) The primary constituent elements of critical habitat for Peck's 
cave amphipod are:
    (i) High-quality water with no or minimal levels of pollutants, 
such as soaps and detergents (Brown 1987, p. 261) and other compounds 
containing surfactants, heavy metals, pesticides, fertilizer nutrients, 
petroleum hydrocarbons, pharmaceuticals and veterinary medicines, and 
semi-volatile compounds, such as industrial cleaning agents, and 
including:
    (A) Low salinity with total dissolved solids that generally range 
from 307 to 368 mg/L; and
    (B) Low turbidity that generally is less than 5 nephelometric 
turbity units;
    (ii) Aquifer water temperatures that range from approximately 68 to 
75 [deg]F (20 to 24 [deg]C); and
    (iii) Food supply that includes detritus (decomposed materials), 
leaf litter, living plant material, algae, fungi,

[[Page 39266]]

bacteria and other microorganisms, and decaying roots.
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, roads, and other paved areas) and the land on 
which they are located existing within the legal boundaries on the 
effective date of this rule. Where lakes are designated, critical 
habitat is only designated for areas where springs occur and does not 
include areas of the lake bottom beyond a radius of 50 ft (15.2 m) from 
the spring outlet.
    (4) Critical habitat map units. Data layers defining map units were 
created by using ArcGIS. All coordinates are UTM zone 14 coordinate 
pairs, referenced to North American Horizontal Datum 1983. Coordinates 
were derived from 2004 digital orthophotographs. All acreage and 
mileage calculations were performed using GIS.
    (5) Note: Index map (Map 1) follows:

BILLING CODE 4310-55-P
[GRAPHIC] [TIFF OMITTED] TR17JY07.000


[[Page 39267]]


    (6) Comal Springs Unit, Comal County, Texas.
    (i) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N): 583387, 3287251; 583392, 3287264; 
583405, 3287280; 583404, 3287290; 583407, 3287301; 583414, 3287307; 
583425, 3287308; 583425, 3287320; 583433, 3287328; 583444, 3287330; 
583454, 3287325; 583463, 3287301; 583482, 3287272; 583486, 3287286; 
583501, 3287296; 583520, 3287314; 583547, 3287326; 583557, 3287333; 
583572, 3287335; 583586, 3287342; 583567, 3287387; 583560, 3287408; 
583559, 3287423; 583534, 3287403; 583499, 3287359; 583491, 3287347; 
583484, 3287340; 583471, 3287334; 583461, 3287334; 583452, 3287340; 
583450, 3287350; 583454, 3287364; 583465, 3287374; 583494, 3287415; 
583521, 3287443; 583526, 3287453; 583563, 3287477; 583589, 3287503; 
583613, 3287519; 583643, 3287547; 583662, 3287561; 583719, 3287617; 
583759, 3287669; 583780, 3287701; 583811, 3287743; 583833, 3287764; 
583848, 3287784; 583892, 3287826; 583911, 3287850; 583970, 3287907; 
584008, 3287938; 584047, 3287963; 584055, 3287964; 584065, 3287960; 
584073, 3287948; 584074, 3287941; 584081, 3287952; 584131, 3288011; 
584164, 3288044; 584183, 3288062; 584197, 3288071; 584216, 3288093; 
584236, 3288110; 584258, 3288138; 584284, 3288161; 584325, 3288209; 
584343, 3288223; 584364, 3288233; 584375, 3288243; 584386, 3288244; 
584401, 3288234; 584403, 3288218; 584433, 3288201; 584437, 3288193; 
584436, 3288184; 584416, 3288167; 584405, 3288167; 584375, 3288184; 
584365, 3288180; 584344, 3288156; 584329, 3288131; 584320, 3288125; 
584298, 3288103; 584273, 3288067; 584204, 3287997; 584187, 3287985; 
584176, 3287973; 584152, 3287943; 584147, 3287933; 584105, 3287880; 
584080, 3287862; 584049, 3287844; 584026, 3287815; 584021, 3287805; 
584013, 3287798; 584009, 3287787; 583999, 3287775; 583971, 3287751; 
583947, 3287735; 583927, 3287725; 583920, 3287718; 583890, 3287704; 
583850, 3287673; 583845, 3287665; 583851, 3287662; 583860, 3287650; 
583865, 3287640; 583865, 3287629; 583863, 3287622; 583854, 3287609; 
583840, 3287600; 583836, 3287584; 583829, 3287576; 583838, 3287552; 
583841, 3287535; 583841, 3287520; 583835, 3287501; 583804, 3287452; 
583790, 3287435; 583766, 3287416; 583727, 3287406; 583706, 3287406; 
583695, 3287398; 583686, 3287370; 583699, 3287298; 583698, 3287288; 
583694, 3287282; 583617, 3287257; 583610, 3287258; 583605, 3287262; 
583597, 3287280; 583584, 3287277; 583565, 3287270; 583541, 3287255; 
583534, 3287244; 583518, 3287233; 583510, 3287211; 583496, 3287192; 
583480, 3287183; 583459, 3287177; 583436, 3287178; 583419, 3287184; 
583400, 3287198; 583396, 3287205; 583387, 3287251.
    (ii) Note: Comal Springs Unit (Map 2) follows:

[[Page 39268]]

[GRAPHIC] [TIFF OMITTED] TR17JY07.001

    (7) Hueco Springs Unit, Comal County, Texas.
    (i) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N): 583113, 3292498; 583114, 3292498; 
583115, 3292498; 583116, 3292498; 583117, 3292498; 583118, 3292497; 
583119, 3292497; 583120, 3292497; 583120, 3292496; 583121, 3292496; 
583122, 3292495; 583123, 3292495; 583124, 3292494; 583124, 3292493; 
583125, 3292493;

[[Page 39269]]

583126, 3292492; 583126, 3292491; 583127, 3292490; 583127, 3292489; 
583127, 3292489; 583128, 3292488; 583128, 3292487; 583128, 3292486; 
583128, 3292485; 583128, 3292484; 583128, 3292483; 583128, 3292482; 
583128, 3292481; 583128, 3292480; 583128, 3292479; 583128, 3292478; 
583127, 3292477; 583127, 3292477; 583127, 3292476; 583126, 3292475; 
583126, 3292474; 583125, 3292473; 583124, 3292473; 583124, 3292472; 
583123, 3292471; 583122, 3292471; 583122, 3292470; 583121, 3292470; 
583120, 3292469; 583119, 3292469; 583118, 3292468; 583117, 3292468; 
583116, 3292468; 583115, 3292468; 583114, 3292468; 583113, 3292468; 
583112, 3292468; 583111, 3292468; 583111, 3292468; 583110, 3292468; 
583109, 3292468; 583108, 3292469; 583107, 3292469; 583106, 3292470; 
583105, 3292470; 583104, 3292471; 583104, 3292471; 583103, 3292472; 
583102, 3292472; 583102, 3292473; 583101, 3292474; 583100, 3292475; 
583100, 3292475; 583100, 3292476; 583099, 3292477; 583099, 3292478; 
583099, 3292479; 583098, 3292480; 583098, 3292481; 583098, 3292482; 
583098, 3292483; 583098, 3292484; 583098, 3292485; 583098, 3292486; 
583098, 3292487; 583099, 3292488; 583099, 3292488; 583099, 3292489; 
583100, 3292490; 583100, 3292491; 583101, 3292492; 583101, 3292493; 
583102, 3292493; 583103, 3292494; 583103, 3292495; 583104, 3292495; 
583105, 3292496; 583106, 3292496; 583107, 3292497; 583108, 3292497; 
583108, 3292497; 583109, 3292498; 583110, 3292498; 583111, 3292498; 
583112, 3292498; 583113, 3292498.
    (ii) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N): 583132, 3292420; 583133, 3292421; 
583133, 3292421; 583133, 3292422; 583134, 3292423; 583134, 3292424; 
583134, 3292425; 583135, 3292426; 583136, 3292426; 583136, 3292427; 
583137, 3292428; 583138, 3292428; 583138, 3292429; 583139, 3292430; 
583140, 3292430; 583141, 3292430; 583142, 3292431; 583143, 3292431; 
583143, 3292431; 583144, 3292432; 583145, 3292432; 583146, 3292432; 
583147, 3292432; 583148, 3292432; 583149, 3292432; 583150, 3292432; 
583151, 3292432; 583152, 3292431; 583153, 3292431; 583154, 3292431; 
583155, 3292430; 583155, 3292430; 583156, 3292429; 583157, 3292429; 
583158, 3292428; 583158, 3292427; 583159, 3292427; 583160, 3292426; 
583160, 3292425; 583161, 3292424; 583161, 3292423; 583162, 3292422; 
583162, 3292422; 583162, 3292421; 583162, 3292420; 583163, 3292419; 
583163, 3292418; 583163, 3292417; 583163, 3292416; 583163, 3292415; 
583162, 3292414; 583162, 3292413; 583162, 3292412; 583162, 3292411; 
583161, 3292410; 583161, 3292409; 583160, 3292409; 583160, 3292408; 
583159, 3292407; 583159, 3292406; 583158, 3292406; 583157, 3292405; 
583156, 3292404; 583156, 3292404; 583156, 3292403; 583155, 3292402; 
583155, 3292402; 583155, 3292401; 583154, 3292400; 583154, 3292399; 
583153, 3292398; 583152, 3292398; 583152, 3292397; 583151, 3292396; 
583150, 3292396; 583149, 3292395; 583149, 3292395; 583148, 3292394; 
583147, 3292394; 583146, 3292393; 583145, 3292393; 583144, 3292393; 
583143, 3292393; 583142, 3292393; 583141, 3292393; 583140, 3292393; 
583139, 3292393; 583138, 3292393; 583137, 3292393; 583137, 3292393; 
583136, 3292394; 583135, 3292394; 583134, 3292395; 583133, 3292395; 
583132, 3292396; 583132, 3292396; 583131, 3292397; 583130, 3292397; 
583129, 3292398; 583129, 3292399; 583128, 3292400; 583128, 3292400; 
583127, 3292401; 583127, 3292402; 583127, 3292403; 583126, 3292404; 
583126, 3292405; 583126, 3292406; 583126, 3292407; 583126, 3292408; 
583126, 3292409; 583126, 3292410; 583126, 3292411; 583126, 3292412; 
583127, 3292413; 583127, 3292413; 583127, 3292414; 583128, 3292415; 
583128, 3292416; 583129, 3292417; 583129, 3292418; 583130, 3292418; 
583131, 3292419; 583131, 3292420; 583132, 3292420.
    (iii) Note: Hueco Springs Unit (Map 3) follows:

[[Page 39270]]

[GRAPHIC] [TIFF OMITTED] TR17JY07.002

* * * * *
    (i) Insects.
* * * * *
    Comal Springs dryopid beetle (Stygoparnus comalensis).
    (1) Critical habitat units are depicted for Comal and Hays 
Counties, Texas, on the maps below.

[[Page 39271]]

    (2) The primary constituent elements of critical habitat for the 
Comal Springs dryopid beetle are:
    (i) High-quality water with no or minimal levels of pollutants, 
such as soaps and detergents (Brown 1987, p. 261) and other compounds 
containing surfactants, heavy metals, pesticides, fertilizer nutrients, 
petroleum hydrocarbons, pharmaceuticals and veterinary medicines, and 
semi-volatile compounds, such as industrial cleaning agents, and 
including:
    (A) Low salinity with total dissolved solids that generally range 
from 307 to 368 mg/L; and
    (B) Low turbidity that generally is less than 5 nephelometric 
turbidity units;
    (ii) Aquifer water temperatures that range from approximately 68 to 
75 [deg]F (20 to 24 [deg]C);
    (iii) A hydrologic regime that allows for adequate spring flows 
that provide levels of dissolved oxygen in the approximate range of 4.0 
to 10.0 mg/L for respiration of the Comal Springs dryopid beetle; and
    (iv) Food supply that includes detritus (decomposed materials), 
leaf litter, living plant material, algae, fungi, bacteria and other 
microorganisms, and decaying roots.
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, roads, and other paved areas) and the land on 
which they are located existing with the legal boundaries on the 
effective date of this rule. Where lakes are designated, critical 
habitat is only designated for areas where springs occur and does not 
include areas of the lake bottom beyond a radius of 50 ft (15.2 m) from 
the spring outlet.
    (4) Critical habitat map units. Data layers defining map units were 
created by using ArcGIS. All coordinates are UTM zone 14 coordinate 
pairs, referenced to North American Horizontal Datum 1983. Coordinates 
were derived from 2004 digital orthophotographs. All acreage and 
mileage calculations were performed using GIS.
    (5) Note: Index map of the critical habitat units for Comal Springs 
dryopid beetle (Map 1) follows:

[[Page 39272]]

[GRAPHIC] [TIFF OMITTED] TR17JY07.003

    (6) Comal Springs Unit, Comal County, Texas.
    (i) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N): 583387, 3287251; 583392, 3287264; 
583405, 3287280; 583404, 3287290; 583407, 3287301; 583414, 3287307; 
583425, 3287308; 583425, 3287320; 583433, 3287328; 583444, 3287330; 
583454, 3287325; 583463, 3287301; 583482, 3287272; 583486, 3287286; 
583501, 3287296; 583520, 3287314; 583547, 3287326; 583557, 3287333; 
583572, 3287335; 583586, 3287342; 583567, 3287387; 583560, 3287408; 
583559, 3287423; 583534, 3287403; 583499, 3287359; 583491, 3287347; 
583484, 3287340; 583471, 3287334; 583461, 3287334; 583452, 3287340; 
583450, 3287350; 583454, 3287364; 583465, 3287374; 583494, 3287415; 
583521, 3287443; 583526, 3287453; 583563, 3287477; 583589, 3287503; 
583613, 3287519; 583643, 3287547; 583662, 3287561; 583719, 3287617; 
583759, 3287669; 583780, 3287701; 583811, 3287743; 583833, 3287764; 
583848, 3287784; 583892, 3287826; 583911, 3287850; 583970, 3287907; 
584008, 3287938; 584047, 3287963; 584055, 3287964; 584065, 3287960; 
584073, 3287948; 584074, 3287941; 584081, 3287952;

[[Page 39273]]

584131, 3288011; 584164, 3288044; 584183, 3288062; 584197, 3288071; 
584216, 3288093; 584236, 3288110; 584258, 3288138; 584284, 3288161; 
584325, 3288209; 584343, 3288223; 584364, 3288233; 584375, 3288243; 
584386, 3288244; 584401, 3288234; 584403, 3288218; 584433, 3288201; 
584437, 3288193; 584436, 3288184; 584416, 3288167; 584405, 3288167; 
584375, 3288184; 584365, 3288180; 584344, 3288156; 584329, 3288131; 
584320, 3288125; 584298, 3288103; 584273, 3288067; 584204, 3287997; 
584187, 3287985; 584176, 3287973; 584152, 3287943; 584147, 3287933; 
584105, 3287880; 584080, 3287862; 584049, 3287844; 584026, 3287815; 
584021, 3287805; 584013, 3287798; 584009, 3287787; 583999, 3287775; 
583971, 3287751; 583947, 3287735; 583927, 3287725; 583920, 3287718; 
583890, 3287704; 583850, 3287673; 583845, 3287665; 583851, 3287662; 
583860, 3287650; 583865, 3287640; 583865, 3287629; 583863, 3287622; 
583854, 3287609; 583840, 3287600; 583836, 3287584; 583829, 3287576; 
583838, 3287552; 583841, 3287535; 583841, 3287520; 583835, 3287501; 
583804, 3287452; 583790, 3287435; 583766, 3287416; 583727, 3287406; 
583706, 3287406; 583695, 3287398; 583686, 3287370; 583699, 3287298; 
583698, 3287288; 583694, 3287282; 583617, 3287257; 583610, 3287258; 
583605, 3287262; 583597, 3287280; 583584, 3287277; 583565, 3287270; 
583541, 3287255; 583534, 3287244; 583518, 3287233; 583510, 3287211; 
583496, 3287192; 583480, 3287183; 583459, 3287177; 583436, 3287178; 
583419, 3287184; 583400, 3287198; 583396, 3287205; 583387, 3287251.
    (ii) Note: Comal Springs Unit (Map 2) follows:

[[Page 39274]]

[GRAPHIC] [TIFF OMITTED] TR17JY07.004

    (7) Fern Bank Springs Unit, Hays County, Texas.
    (i) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N): 595131, 3317374; 595131, 3317375; 
595132, 3317376; 595132, 3317377; 595132, 3317378; 595132, 3317379; 
595133, 3317380; 595133, 3317381; 595133, 3317382; 595134, 3317383; 
595135, 3317383; 595135, 3317384; 595136, 3317385; 595137, 3317386; 
595137, 3317386;

[[Page 39275]]

595138, 3317387; 595139, 3317387; 595140, 3317388; 595141, 3317388; 
595141, 3317388; 595168, 3317398; 595181, 3317411; 595198, 3317428; 
595198, 3317428; 595199, 3317429; 595199, 3317430; 595200, 3317430; 
595201, 3317431; 595202, 3317431; 595203, 3317432; 595204, 3317432; 
595205, 3317432; 595206, 3317432; 595207, 3317433; 595208, 3317433; 
595209, 3317433; 595210, 3317433; 595211, 3317433; 595212, 3317433; 
595213, 3317432; 595214, 3317432; 595214, 3317432; 595215, 3317431; 
595216, 3317431; 595217, 3317430; 595218, 3317430; 595219, 3317429; 
595219, 3317428; 595220, 3317428; 595221, 3317427; 595237, 3317406; 
595237, 3317406; 595238, 3317405; 595238, 3317404; 595239, 3317404; 
595239, 3317403; 595239, 3317402; 595240, 3317401; 595240, 3317400; 
595240, 3317400; 595240, 3317399; 595240, 3317398; 595240, 3317397; 
595240, 3317396; 595240, 3317395; 595240, 3317394; 595240, 3317394; 
595240, 3317393; 595239, 3317392; 595239, 3317391; 595239, 3317390; 
595238, 3317389; 595238, 3317388; 595237, 3317388; 595237, 3317388; 
595223, 3317369; 595223, 3317369; 595222, 3317368; 595221, 3317367; 
595221, 3317366; 595220, 3317366; 595219, 3317365; 595218, 3317365; 
595217, 3317364; 595217, 3317364; 595173, 3317343; 595173, 3317343; 
595172, 3317343; 595171, 3317342; 595170, 3317342; 595169, 3317342; 
595168, 3317342; 595167, 3317342; 595166, 3317342; 595165, 3317342; 
595164, 3317342; 595163, 3317342; 595162, 3317343; 595146, 3317347; 
595146, 3317348; 595145, 3317348; 595144, 3317348; 595143, 3317349; 
595142, 3317349; 595141, 3317350; 595141, 3317350; 595141, 3317350; 
595140, 3317351; 595139, 3317352; 595139, 3317352; 595139, 3317353; 
595138, 3317353; 595138, 3317354; 595137, 3317355; 595137, 3317356; 
595136, 3317357; 595136, 3317357; 595132, 3317369; 595132, 3317370; 
595132, 3317370; 595132, 3317371; 595132, 3317372; 595131, 3317373; 
595131, 3317374.
    (ii) Note: Fern Bank Springs Unit (Map 3) follows:

[[Page 39276]]

[GRAPHIC] [TIFF OMITTED] TR17JY07.005

* * * * *
    Comal Springs riffle beetle (Heterelmis comalensis).
    (1) Critical habitat units are depicted for Comal and Hays 
Counties, Texas, on the maps below.
    (2) The primary constituent elements of critical habitat for Comal 
Springs riffle beetle are:

[[Page 39277]]

    (i) High-quality water with no or minimal levels of pollutants, 
such as soaps and detergents (Brown 1987, p. 261) and other compounds 
containing surfactants, heavy metals, pesticides, fertilizer nutrients, 
petroleum hydrocarbons, pharmaceuticals and veterinary medicines, and 
semi-volatile compounds, such as industrial cleaning agents, and 
including:
    (A) Low salinity with total dissolved solids that generally range 
from 307 to 368 mg/L; and
    (B) Low turbidity that generally is less than 5 nephelometric 
turbidity units;
    (ii) Aquifer water temperatures that range from approximately 68 to 
75 [deg]F (20 to 24 [deg]C);
    (iii) A hydrologic regime that allows for adequate spring flows 
that provide levels of dissolved oxygen in the approximate range of 4.0 
to 10.0 mg/L for respiration of the Comal Springs riffle beetle;
    (iv) Food supply that includes detritus (decomposed materials), 
leaf litter, living plant material, algae, fungi, bacteria and other 
microorganisms, and decaying roots; and
    (v) Bottom substrate in surface water habitat of the Comal Springs 
riffle beetle that is free of sand and silt, and is composed of gravel 
and cobble ranging in size from 0.3 to 5.0 inches (8 to 128 
millimeters).
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, roads, and other paved areas) and the land on 
which they are located existing within the legal boundaries on the 
effective date of this rule.
    (4) Critical habitat map units. Data layers defining map units were 
created by using ArcGIS. All coordinates are UTM zone 14 coordinate 
pairs, referenced to North American Horizontal Datum 1983. Coordinates 
were derived from 2004 digital orthophotographs. All acreage and 
mileage calculations were performed using GIS.
    (5) Note: Index map of the critical habitat units for Comal Springs 
riffle beetle (Map 1) follows:

[[Page 39278]]

[GRAPHIC] [TIFF OMITTED] TR17JY07.006

    (6) Comal Springs Unit, Comal County, Texas.
    (i) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N): 583420, 3287293; 583423, 3287293; 
583426, 3287293; 583428, 3287290; 583429, 3287285; 583428, 3287280; 
583426, 3287273; 583422, 3287268; 583416, 3287259; 583415, 3287255; 
583415, 3287249; 583417, 3287238; 583418, 3287233; 583419, 3287228; 
583418, 3287222; 583421, 3287221; 583427, 3287216; 583429, 3287207; 
583435, 3287204; 583442, 3287203; 583455, 3287203; 583464, 3287203; 
583468, 3287205; 583475, 3287209; 583479, 3287213; 583479, 3287217; 
583483, 3287224; 583486, 3287232; 583490, 3287246; 583491, 3287248; 
583485, 3287247; 583481, 3287245; 583476, 3287243; 583471, 3287241; 
583461, 3287239; 583460, 3287242; 583460, 3287248; 583459, 3287255; 
583459, 3287261; 583458, 3287266; 583455, 3287272; 583455, 3287277; 
583452, 3287282; 583449, 3287284; 583446, 3287288; 583445, 3287295; 
583441, 3287307; 583439, 3287314; 583443, 3287315; 583444, 3287309; 
583446, 3287303; 583449, 3287293; 583450, 3287291; 583453, 3287288; 
583457, 3287284; 583461, 3287278; 583466, 3287271; 583468, 3287263; 
583469, 3287255; 583470, 3287251; 583480, 3287257; 583484, 3287256; 
583488, 3287254;

[[Page 39279]]

583492, 3287253; 583493, 3287254; 583496, 3287255; 583500, 3287257; 
583503, 3287258; 583507, 3287260; 583509, 3287261; 583509, 3287262; 
583509, 3287265; 583508, 3287266; 583504, 3287270; 583502, 3287270; 
583499, 3287270; 583497, 3287271; 583497, 3287273; 583498, 3287276; 
583500, 3287277; 583502, 3287279; 583505, 3287281; 583508, 3287282; 
583512, 3287285; 583516, 3287291; 583521, 3287294; 583525, 3287298; 
583528, 3287301; 583531, 3287303; 583535, 3287305; 583540, 3287306; 
583544, 3287309; 583551, 3287311; 583556, 3287313; 583560, 3287317; 
583563, 3287319; 583567, 3287320; 583571, 3287320; 583575, 3287320; 
583578, 3287321; 583580, 3287322; 583583, 3287324; 583587, 3287326; 
583592, 3287328; 583595, 3287329; 583597, 3287330; 583600, 3287331; 
583603, 3287332; 583604, 3287333; 583605, 3287337; 583605, 3287340; 
583604, 3287344; 583601, 3287346; 583598, 3287353; 583593, 3287363; 
583589, 3287371; 583587, 3287378; 583581, 3287392; 583580, 3287400; 
583575, 3287411; 583574, 3287420; 583575, 3287430; 583575, 3287435; 
583575, 3287438; 583575, 3287441; 583574, 3287442; 583573, 3287442; 
583572, 3287442; 583569, 3287441; 583567, 3287442; 583563, 3287442; 
583558, 3287441; 583553, 3287437; 583549, 3287435; 583542, 3287429; 
583539, 3287428; 583536, 3287425; 583533, 3287420; 583524, 3287415; 
583516, 3287405; 583510, 3287398; 583505, 3287392; 583499, 3287383; 
583494, 3287378; 583486, 3287368; 583482, 3287361; 583479, 3287356; 
583475, 3287353; 583467, 3287349; 583465, 3287349; 583466, 3287355; 
583468, 3287356; 583470, 3287357; 583471, 3287359; 583473, 3287361; 
583475, 3287362; 583479, 3287367; 583485, 3287377; 583491, 3287386; 
583498, 3287395; 583506, 3287406; 583509, 3287407; 583511, 3287412; 
583523, 3287423; 583533, 3287434; 583535, 3287437; 583537, 3287442; 
583549, 3287449; 583558, 3287455; 583565, 3287461; 583571, 3287464; 
583576, 3287468; 583584, 3287478; 583598, 3287491; 583610, 3287498; 
583623, 3287507; 583635, 3287519; 583653, 3287536; 583672, 3287549; 
583685, 3287562; 583697, 3287574; 583731, 3287607; 583739, 3287618; 
583753, 3287634; 583761, 3287645; 583772, 3287660; 583784, 3287679; 
583792, 3287692; 583809, 3287716; 583823, 3287733; 583844, 3287754; 
583859, 3287773; 583870, 3287784; 583883, 3287797; 583903, 3287816; 
583913, 3287829; 583922, 3287839; 583933, 3287849; 583941, 3287857; 
583951, 3287867; 583961, 3287878; 583971, 3287886; 583980, 3287896; 
583991, 3287905; 584005, 3287917; 584017, 3287926; 584024, 3287931; 
584038, 3287941; 584049, 3287948; 584052, 3287949; 584055, 3287948; 
584056, 3287945; 584059, 3287941; 584059, 3287937; 584055, 3287935; 
584054, 3287932; 584055, 3287929; 584060, 3287926; 584067, 3287926; 
584071, 3287924; 584078, 3287920; 584081, 3287921; 584085, 3287929; 
584093, 3287942; 584108, 3287958; 584116, 3287970; 584128, 3287984; 
584142, 3288000; 584150, 3288007; 584157, 3288014; 584163, 3288021; 
584169, 3288027; 584174, 3288033; 584181, 3288039; 584187, 3288044; 
584192, 3288050; 584207, 3288060; 584216, 3288071; 584227, 3288082; 
584239, 3288093; 584247, 3288099; 584251, 3288104; 584255, 3288109; 
584261, 3288116; 584265, 3288121; 584270, 3288128; 584277, 3288132; 
584282, 3288138; 584289, 3288144; 584296, 3288151; 584303, 3288161; 
584313, 3288171; 584318, 3288178; 584328, 3288188; 584336, 3288198; 
584342, 3288201; 584347, 3288204; 584349, 3288207; 584352, 3288210; 
584357, 3288212; 584360, 3288215; 584366, 3288217; 584371, 3288219; 
584374, 3288221; 584378, 3288225; 584382, 3288229; 584388, 3288225; 
584388, 3288224; 584388, 3288220; 584388, 3288216; 584388, 3288214; 
584389, 3288211; 584389, 3288209; 584395, 3288205; 584401, 3288203; 
584422, 3288191; 584411, 3288181; 584393, 3288192; 584382, 3288198; 
584376, 3288200; 584371, 3288199; 584363, 3288197; 584355, 3288191; 
584348, 3288183; 584340, 3288175; 584332, 3288165; 584326, 3288157; 
584319, 3288147; 584316, 3288143; 584317, 3288141; 584316, 3288140; 
584314, 3288141; 584309, 3288136; 584303, 3288129; 584286, 3288113; 
584277, 3288100; 584269, 3288089; 584261, 3288077; 584253, 3288071; 
584240, 3288057; 584236, 3288052; 584228, 3288045; 584219, 3288035; 
584210, 3288026; 584203, 3288019; 584193, 3288008; 584183, 3288002; 
584176, 3287996; 584169, 3287987; 584165, 3287984; 584158, 3287974; 
584150, 3287966; 584139, 3287951; 584135, 3287942; 584127, 3287933; 
584114, 3287915; 584105, 3287905; 584094, 3287891; 584082, 3287884; 
584072, 3287875; 584059, 3287867; 584047, 3287862; 584038, 3287855; 
584033, 3287848; 584025, 3287840; 584019, 3287830; 584016, 3287827; 
584016, 3287827; 584013, 3287824; 584011, 3287820; 584009, 3287814; 
584005, 3287811; 584000, 3287806; 583996, 3287795; 583988, 3287786; 
583982, 3287780; 583972, 3287771; 583962, 3287764; 583950, 3287757; 
583939, 3287748; 583928, 3287743; 583917, 3287737; 583917, 3287737; 
583912, 3287731; 583895, 3287724; 583881, 3287717; 583872, 3287708; 
583860, 3287701; 583847, 3287692; 583838, 3287683; 583829, 3287669; 
583828, 3287663; 583830, 3287659; 583835, 3287653; 583840, 3287651; 
583843, 3287647; 583847, 3287642; 583850, 3287636; 583850, 3287630; 
583847, 3287625; 583842, 3287619; 583836, 3287616; 583829, 3287611; 
583824, 3287603; 583823, 3287597; 583822, 3287591; 583820, 3287588; 
583814, 3287587; 583813, 3287583; 583812, 3287580; 583814, 3287575; 
583815, 3287570; 583817, 3287565; 583820, 3287558; 583824, 3287548; 
583826, 3287541; 583826, 3287534; 583826, 3287522; 583823, 3287515; 
583821, 3287507; 583813, 3287493; 583807, 3287485; 583803, 3287481; 
583803, 3287478; 583799, 3287472; 583792, 3287462; 583779, 3287446; 
583769, 3287437; 583757, 3287428; 583753, 3287427; 583746, 3287426; 
583734, 3287423; 583725, 3287421; 583715, 3287420; 583709, 3287421; 
583702, 3287421; 583696, 3287418; 583689, 3287413; 583683, 3287407; 
583679, 3287400; 583677, 3287393; 583674, 3287383; 583671, 3287371; 
583672, 3287360; 583675, 3287341; 583678, 3287324; 583680, 3287312; 
583684, 3287297; 583684, 3287293; 583616, 3287272; 583615, 3287275; 
583610, 3287289; 583606, 3287294; 583601, 3287295; 583595, 3287296; 
583592, 3287294; 583580, 3287292; 583569, 3287288; 583557, 3287283; 
583548, 3287276; 583539, 3287271; 583531, 3287267; 583525, 3287260; 
583523, 3287255; 583517, 3287253; 583513, 3287248; 583507, 3287243; 
583502, 3287236; 583500, 3287228; 583497, 3287219; 583493, 3287213; 
583486, 3287203; 583474, 3287197; 583458, 3287192; 583447, 3287192; 
583439, 3287193; 583434, 3287196; 583430, 3287198; 583428, 3287197; 
583424, 3287198; 583422, 3287201; 583419, 3287203; 583415, 3287205; 
583411, 3287209; 583409, 3287221; 583406, 3287230; 583404, 3287240; 
583402, 3287251; 583405, 3287256; 583408, 3287259; 583412, 3287263; 
583417, 3287270; 583420, 3287276; 583422, 3287279; 583421, 3287282; 
583419, 3287285; 583419, 3287288; 583420, 3287293.
    (ii) Note: Comal Springs Unit (Map 2) follows:

BILLING CODE 4310-55-P

[[Page 39280]]

[GRAPHIC] [TIFF OMITTED] TR17JY07.007

    (7) San Marcos Springs Unit, Hays County, Texas.
    (i) Aquatic habitat areas bounded by the UTM Zone 14 NAD 83 
coordinates (meters E, meters N): 602869, 3307092; 602870, 3307100; 
602877, 3307131; 602892, 3307172; 602926, 3307215; 602936, 3307229; 
602942, 3307237; 602945, 3307243; 602957, 3307286; 603007, 3307329; 
603072, 3307386; 603154, 3307462; 603158, 3307463; 603166, 3307466; 
603175, 3307465;

[[Page 39281]]

603186, 3307473; 603219, 3307486; 603258, 3307508; 603288, 3307526; 
603307, 3307541; 603317, 3307544; 603326, 3307539; 603329, 3307527; 
603319, 3307512; 603251, 3307456; 603234, 3307439; 603224, 3307433; 
603218, 3307419; 603206, 3307412; 603192, 3307406; 603175, 3307418; 
603170, 3307419; 603153, 3307414; 603144, 3307404; 603141, 3307389; 
603145, 3307379; 603147, 3307369; 603152, 3307352; 603141, 3307339; 
603135, 3307339; 603124, 3307337; 603120, 3307336; 603116, 3307335; 
603114, 3307325; 603109, 3307318; 603105, 3307315; 603104, 3307314; 
603100, 3307310; 603024, 3307239; 603023, 3307240; 603019, 3307237; 
603017, 3307233; 603026, 3307203; 603035, 3307187; 603038, 3307178; 
603038, 3307166; 603033, 3307148; 603027, 3307138; 603018, 3307123; 
603002, 3307117; 602983, 3307109; 602968, 3307097; 602962, 3307105; 
602962, 3307105; 602965, 3307112; 602963, 3307116; 602958, 3307119; 
602954, 3307123; 602946, 3307126; 602938, 3307129; 602928, 3307129; 
602921, 3307129; 602913, 3307128; 602896, 3307105; 602894, 3307101; 
602887, 3307097; 602881, 3307091; 602883, 3307087; 602877, 3307082; 
602875, 3307084; 602872, 3307087; 602869, 3307092.
    (ii) Note: San Marcos Springs Unit (Map 3) follows:

[[Page 39282]]

[GRAPHIC] [TIFF OMITTED] TR17JY07.008


[[Page 39283]]


* * * * *

    Dated: June 28, 2007.
David M. Verhey,
Acting Assistant Secretary for Fish and Wildlife and Parks.
[FR Doc. 07-3267 Filed 7-16-07; 8:45 am]

BILLING CODE 4310-55-C