Tuesday, July 17, 2007 Part III Department of the Interior Fish and Wildlife Service 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 VerDate Aug<31>2005 15:16 Jul 16, 2007 Jkt 211001 PO 00000 Frm 00001 Fmt 4717 Sfmt 4717 E:\FR\FM\17JYR3.SGM 17JYR3 rfrederick on PROD1PC67 with RULES3 39248 Federal Register / Vol. 72, No. 136 / Tuesday, July 17, 2007 / Rules and Regulations DEPARTMENT OF THE INTERIOR Comal County, Texas. The Comal second) (Fahlquist and Slattery 1997, p. Springs dryopid beetle is a subterranean 1; Slattery and Fahlquist 1997, p. 1). Fish and Wildlife Service insect with vestigial (poorly developed, Both spring systems emerge as a series non-functional) eyes. The species has of spring outlets along the Balcones 50 CFR Part 17 been found in two spring systems, fault that follows the edge of the RIN 1018–AU75 Comal Springs and Fern Bank Springs, Edwards Plateau in Texas. Fern Bank that are located in Comal and Hays Springs and Hueco Springs have Endangered and Threatened Wildlife Counties, respectively. The Comal considerably smaller flows and consist and Plants; Designation of Critical Springs riffle beetle is an aquatic insect of one main spring with several satellite Habitat for the Peck’s Cave Amphipod, that is found in and primarily restricted springs or seep areas. Comal Springs Dryopid Beetle, and to surface water associated with Comal The four spring systems designated Comal Springs Riffle Beetle Springs in Comal County and with San for critical habitat are characterized by Marcos Springs in Hays County. high water quality and relatively AGENCY: Fish and Wildlife Service, The four spring systems (Comal, Fern constant water flows, with temperatures Interior. Bank, Hueco, and San Marcos) that range from 68 to 75 °F (Fahrenheit) ° ACTION: Final rule. designated as critical habitat units are (20 to 24 C (Celsius)). Due to the produced by discharge of aquifer spring underlying limestone aquifer, SUMMARY: We, the U.S. Fish and water along the Balcones fault zone at discharged water from these springs has Wildlife Service (Service), are the edge of the Edwards Plateau in a carbonate chemistry (Ogden et al. designating critical habitat for the Peck’s central Texas. The source of water flows 1986, p. 103). Although flows from San cave amphipod (Stygobromus pecki), for Comal Springs and San Marcos Marcos Springs can vary according to Comal Springs dryopid beetle Springs is the San Antonio segment of fluctuations in the source aquifer, (Stygoparnus comalensis), and Comal the Edwards Aquifer. This aquifer is records indicate that this spring system Springs riffle beetle (Heterelmis characterized by highly varied, below has never ceased flowing. San Marcos comalensis) in areas of occupied, ground spaces that have been hollowed Springs has been monitored since 1894, spring-related aquatic habitat in Texas out within limestone bedrock through and has exhibited the greatest flow under the Endangered Species Act of dissolution by rainwater. Groundwater dependability of any major spring 1973, as amended (Act). The three listed is held and conveyed within these system in central Texas (Puente 1976, p. species are known only from four spring hollowed-out spaces, which range in 27). Comal Springs has a flow record systems in central Texas: Comal Springs size from honeycomb-like pores to large nearly comparable to that of San Marcos and Hueco Springs in Comal County, caverns. The San Antonio segment of Springs; however, Comal Springs ceased and Fern Bank Springs and San Marcos the aquifer occurs in a crescent-shaped flowing from June 13 to November 3, Springs in Hays County. The total area section over a distance of 176 miles (mi) 1956, during a severe drought (U.S. designated as critical habitat for the (283 kilometers (km)), from the town of Army Corps of Engineers 1965, p. 59). amphipod is about 38.5 acres (ac) (15.6 Brackettville in Kinney County on the Water pumping from the aquifer hectares (ha)), for the dryopid beetle it segment’s west side over to the town of contributed to cessation of flow at is about 39.5 ac (16.0 ha), and for the Kyle in Hays County at the segment’s Comal Springs during the drought riffle beetle it is about 30.3 ac (12.3 ha). northeast side. Groundwater generally period (U.S. Army Corps of Engineers DATES: This rule becomes effective on moves from recharge areas in the 1965, p. 59). Hueco Springs has gone August 16, 2007. southwest part of the San Antonio dry a number of times in the past during segment and travels toward discharge drought periods (Puente 1976, p. 27; FOR FURTHER INFORMATION CONTACT: areas in the northeast part of the Guyton and Associates 1979, p. 46). Adam Zerrenner, Field Supervisor, segment, which includes Comal Springs Although flow records are unavailable Austin Ecological Services Office, 10711 and San Marcos Springs. The area that for Fern Bank Springs, the spring system Burnet Road, Suite 200, Austin, TX recharges groundwater coming to Comal is considered to be perennial (Barr 1993, 78758 (telephone 512–490–0057; Springs may occur as much as 62 mi p. 39). facsimile 512–490–0974). (100 km) away from the springs (Brune Each of the four spring systems and SUPPLEMENTARY INFORMATION: 1981, p. 130). Hueco Springs is related subterranean aquifers typically Background recharged locally from the local provide adequate resources to sustain watershed basin and possibly by the San life cycle functions for resident It is our intent to discuss only those Antonio segment of the Edwards populations of the Peck’s cave topics directly relevant to the Aquifer (Guyton and Associates 1979, p. amphipod, Comal Springs dryopid designation of critical habitat in this 2). The source of water for Fern Bank beetle, and Comal Springs riffle beetle. rule. For more information on these Springs has not been determined. Fern However, a primary threat to the three species, refer to the final rule listing the Bank Springs discharges water from the invertebrate species is the potential Peck’s cave amphipod, Comal Springs upper member of the Glen Rose failure of spring flow due to drought or dryopid beetle, and Comal Springs riffle Formation, and its flow could originate excessive groundwater pumping, which beetle that was published in the Federal primarily from that unit; however, water could result in loss of aquatic habitat for Register on December 18, 1997 (62 FR discharged from the springs could also the species. Although these invertebrate 66295). be (1) Drainage from the nearby species persisted at Comal Springs in All three of the listed species Edwards Aquifer recharge zone, (2) the 1950s despite drought conditions included in this final rule for critical water lost from the Blanco River, or (3) (Bowles et al. 2003, p. 379), all three habitat designation are freshwater a combination of all three sources (Veni species are aquatic and require water to invertebrates. The Peck’s cave 2006, p.1). complete their individual life cycles. amphipod is an eyeless, subterranean Comal Springs and San Marcos Bowles et al. (2003, p. 379) pointed (below ground) arthropod that has been Springs are the two largest spring out that the mechanism by which the found in Comal Springs and Hueco systems in Texas with respective mean Comal Springs riffle beetle survived the Springs (also spelled Waco Springs). annual flows of 284 and 170 cubic feet drought and the extent to which its Both spring systems are located in per second (8 and 5 cubic meters per population was negatively impacted are VerDate Aug<31>2005 15:16 Jul 16, 2007 Jkt 211001 PO 00000 Frm 00002 Fmt 4701 Sfmt 4700 E:\FR\FM\17JYR3.SGM 17JYR3 rfrederick on PROD1PC67 with RULES3 Federal Register / Vol. 72, No. 136 / Tuesday, July 17, 2007 / Rules and Regulations 39249 uncertain. Bowles et al. (2003, p. 379) During the second comment period, we are important factors in maintaining the speculated that the riffle beetle may be received one comment from a peer life history functions of the Peck’s cave able to retreat back into spring openings reviewer and four from organizations; amphipod, the Comal Springs dryopid or burrow down to wet areas below the two of which included comments on the beetle, and the Comal Springs riffle surface of the streambed. economic analysis. Responses to all beetle by highlighting the role of water Barr (1993, p. 55) found Comal comments were grouped by those from in the descriptions of PCEs 1, 2, and 3 Springs dryopid beetles in spring flows peer reviewers, followed by public of this final rule. We clarified the with low volume discharge as well as comments. These comments are language for PCE 3 to highlight the high volume discharge and suggested addressed in the following summary importance of spring flows in that presence of the species did not and incorporated into the final rule as maintaining adequate dissolved oxygen necessarily depend on a high spring appropriate. We did not receive any levels. We also state in the Special flow. However, Barr (1993, p. 61) noted requests for a public hearing and thus Management Considerations section of that effects on both subterranean species no public hearing was held. this rule that prolonged cessation of (dryopid beetle and amphipod) from spring flows as a result of the loss of Peer Review extended loss of spring flow and low hydrological connectivity within the aquifer levels could not be predicted In accordance with our policy aquifer may require special management due to limited knowledge about their published on July 1, 1994 (59 FR considerations, such as maintenance of life cycles.