Wednesday, February 19, 2003 Part II Department of the Interior Fish and Wildlife Service 50 CFR Part 17 Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Rio Grande Silvery Minnow; Final Rule VerDate Jan<31>2003 16:12 Feb 18, 2003 Jkt 200001 PO 00000 Frm 00001 Fmt 4717 Sfmt 4717 E:\FR\FM\19FER2.SGM 19FER2 8088 Federal Register / Vol. 68, No. 33 / Wednesday, February 19, 2003 / Rules and Regulations DEPARTMENT OF THE INTERIOR National Environmental Policy Act Rio Grande (Pflieger 1980). The silvery (NEPA) and a new proposed rule minnow is extirpated from the Pecos Fish and Wildlife Service designating critical habitat for the River and also from the Rio Grande silvery minnow. downstream of Elephant Butte Reservoir 50 CFR Part 17 DATES: This final rule is effective March and upstream of Cochiti Reservoir RIN 1018–AH91 21, 2003. (Bestgen and Platania 1991). The current ADDRESSES: Comments and materials distribution of the silvery minnow is Endangered and Threatened Wildlife received, as well as supporting limited to the Rio Grande between and Plants; Designation of Critical documentation used in the preparation Cochiti Dam and Elephant Butte Habitat for the Rio Grande Silvery of this final rule, are available for public Reservoir. Throughout much of its Minnow inspection, by appointment, during historic range, the decline of the silvery normal business hours at the New minnow has been attributed to AGENCY: Fish and Wildlife Service, modification of the flow regime Interior. Mexico Ecological Services Field Office, 2105 Osuna Road NE, Albuquerque, NM (hydrological pattern of flows that vary ACTION: Final rule; notice of availability. 87113. seasonally in magnitude and duration, depending on annual precipitation SUMMARY: We, the U.S. Fish and You may obtain copies of the final patterns such as runoff from snowmelt) Wildlife Service (Service), designate rule, the economic analysis, or the final and channel drying resulting from critical habitat for the Rio Grande EIS from the field office address above impoundments, water diversion for silvery minnow (Hybognathus amarus) or by calling 505–346–2525. All agriculture, stream channelization, and (silvery minnow), an endangered documents are also available from our perhaps both interactions with non- species under the Endangered Species Web site at http://ifw2es.fws.gov/ native fish and decreasing water quality Act of 1973, as amended (Act). On June Library/. (Cook et al. 1992; Bestgen and Platania 6, 2002, we proposed that 212 miles If you would like copies of the regulations on listed wildlife or have 1991; Service 1999; Buhl 2001). (mi) (339 kilometers (km)) be designated Much of the species’ life history questions about prohibitions and as critical habitat for the silvery information detailed below comes from permits, contact the U.S. Fish and minnow. The silvery minnow critical studies conducted within the middle Wildlife Service, Division of habitat designation in the Rio Grande Rio Grande, the current range of the Endangered Species, P.O. Box 1306, extends from Cochiti Dam, Sandoval silvery minnow. Nevertheless, we Albuquerque, NM 87103. County, New Mexico (NM) downstream believe that our determinations for other to the utility line crossing the Rio FOR FURTHER INFORMATION CONTACT: areas outside of the middle Rio Grande, Grande, a permanent identified Field Supervisor, New Mexico but within the historic range of the landmark in Socorro County, NM, a Ecological Services Field Office (see silvery minnow, are consistent with the total of approximately 157 mi (252 km), ADDRESSES section above); telephone: data collected to date on the species’ referred to as the ‘‘middle Rio Grande.’’ 505–346–2525. Division of Endangered ecological requirements (e.g., Service The designation also includes the Species (see ADDRESSES section above); 1999). tributary Jemez River from Jemez telephone 505–248–6920; facsimile The role of the plains minnow Canyon Dam in NM to the upstream 505–248–6788. (Hybognathus placitus) in the decline boundary of Santa Ana Pueblo, which is SUPPLEMENTARY INFORMATION: and extirpation of the silvery minnow not included. The critical habitat from the Pecos River is uncertain; Background designation defines the lateral extent however, the establishment of the plains (width) as those areas bounded by The Rio Grande silvery minnow is minnow coincided with the existing levees or, in areas without one of seven species in the genus disappearance of the silvery minnow levees, 300 feet (ft) (91.4 meters (m)) of Hybognathus found in the United States from the Pecos River (Bestgen and riparian zone adjacent to each side of (Pflieger 1980). The species was first Platania 1991; Cook et al. 1992). Cook et the bankfull stage of the middle Rio described by Girard (1856) from al. (1992) believed that the non-native Grande. The Pueblo lands of Santo specimens taken from the Rio Grande plains minnow was introduced into the Domingo, Santa Ana, Sandia, and Isleta near Fort Brown, Cameron County, TX. Pecos drainage prior to 1964, and was within this area are not included in the It is a stout silvery minnow with probably the result of the release of final critical habitat designation. Except moderately small eyes and a small, ‘‘bait minnows’’ collected from the for these areas, the final remaining slightly oblique mouth. Adults may Arkansas River drainage. It is unclear, portion of the silvery minnow’s reach 3.5 inches (in) (90 millimeters however, if populations of the native occupied range in the middle Rio (mm)) in total length (Sublette et al. silvery minnow were depleted prior to Grande in NM is being designated as 1990). Its dorsal fin is distinctly pointed the introduction of the plains minnow, critical habitat. This publication also with the front of it located slightly or if the reduction and extirpation of the provides notice of the availability of the closer to the tip of the snout than to the silvery minnow was a consequence of final economic analysis and the final base of the tail. The fish is silver with the interactions between the two species Environmental Impact Statement (EIS) emerald reflections. Its belly is silvery (C. Hoagstrom, U.S. Fish and Wildlife for this final rule. white, its fins are plain, and barbels are Service, pers. comm. 2001). One theory This final rule and EIS are being absent (Sublette et al. 1990). is that the plains minnow may be more issued pursuant to a court order. On This species was historically one of tolerant of modified habitats and, November 21, 2000, the United States the most abundant and widespread therefore, was able to replace the silvery District Court for the District of New fishes in the Rio Grande Basin, minnow in the degraded reaches of the Mexico, in Middle Rio Grande occurring from Espan˜ ola, NM, to the Pecos River. Nevertheless, the plains Conservancy District v. Babbitt, 206 F. Gulf of Mexico (Bestgen and Platania minnow has experienced population Supp. 2d 1156 (D.N.M. 2000), set aside 1991). It was also found in the Pecos declines within its native range from the July 6, 1999, critical habitat River, a major tributary of the Rio highly variable water levels, unstable designation for the minnow and ordered Grande, from Santa Rosa, NM, streambeds, and fluctuating water us to issue both an EIS pursuant to the downstream to its confluence with the temperatures (Cross et al. 1985, cited in VerDate Jan<31>2003 18:34 Feb 18, 2003 Jkt 200001 PO 00000 Frm 00002 Fmt 4701 Sfmt 4700 E:\FR\FM\19FER2.SGM 19FER2 Federal Register / Vol. 68, No. 33 / Wednesday, February 19, 2003 / Rules and Regulations 8089 Taylor and Miller 1990). Although the Robinson 1959; Hubbs et al. 1977; salmoides), smallmouth bass (M. interactions (e.g., hybridization or Edwards and Contreras-Balderas 1991). dolomieu)) as these species were competition) between the silvery Prior to measurable human influence stocked into the reservoirs created by minnow and the introduced plains on the middle Rio Grande, starting in the dams (e.g., Cochiti Reservoir) minnow are believed by some to be one the 1300’s, (Biella and Chapman 1977), (Sublette et al. 1990). Once established, of the primary causes for the extirpation the Rio Grande was a perennially these species often completely replaced of the silvery minnow in the Pecos flowing, aggrading river with a shifting the native fish fauna (Propst et al. 1987; River, this hypothesis is unsubstantiated sand substrate. In general, the river was Propst 1999). (Hatch et al. 1985; Bestgen et al. 1989; slightly sinuous and braided, and freely Development of agriculture and the Cook et al. 1992). Currently, New migrated across the floodplain. Strong growth of cities within the historic Mexico State University is conducting evidence now suggests that the middle range of the silvery minnow resulted in research on the plains minnow and Rio Grande started drying up on a fairly a decrease in the quality of river water silvery minnow to determine if the two regular basis only after the development caused by municipal and agricultural species hybridize. These studies are of Colorado’s San Luis Valley in the runoff (i.e., sewage and pesticides) that ongoing and results should be available 1870’s. Prior to this, there are only two may have also adversely affected the in 2003 (C. Caldwell, U.S. Geological examples of its flow ceasing, during range and distribution of the silvery Survey, Biological Resources Division prolonged, severe droughts in 1752 and minnow. Historically there were four pers. comm. 2002). 1861. Over the past century, and other small native fish species (speckled Within its native range, the plains particularly in the last few decades, the chub (Macrohybopsis aestivalis); Rio minnow is sympatric (occurs at the middle Rio Grande has been frequently Grande shiner (Notropis jemezanus); same localities) with other species of dewatered, particularly in the river phantom shiner (Notropis orca); and Rio Hybognathus, but is separated reach from Isleta Diversion Dam to the Grande bluntnose shiner (Notropis ecologically from them.