(DRAFT) - Taxonomy
                               Species SUCKER, WARNER
                                Species Id ESIS251016
                                   Date 14 MAR 96



TAXONOMY

NAME - SUCKER, WARNER OTHER COMMON NAMES - SUCKER, WARNER; SUCKER, TAHOE; COARSE-SCALED SUCKER OF WARNER LAKE BASIN; SUCKER, COARSE-SCALED and WARNER LAKE BASIN; RED HORSE ELEMENT CODE - CATEGORY - Fish PHYLUM AND SUBPHYLUM - CHORDATA, CLASS AND SUBCLASS - OSTEICHTHYES, ORDER AND SUBORDER - CYPRINIFORMES, FAMILY AND SUBFAMILY - CATOSTOMIDAE, GENUS AND SUBGENUS - CATOSTOMUS, SPECIES AND SSP - WARNERENSIS, SCIENTIFIC NAME - CATOSTOMUS WARNERENSIS AUTHORITY - TAXONOMY REFERENCES - COMMENTS ON TAXONOMY - Warner Sucker Catostomus warnerensis Snyder, 1908 KINGDOM: Animal GROUP: Fish PHYLUM: Chordata CLASS: Osteichthyes ORDER: Cypriniformes FAMILY: Catostomidae Snyder (19) described Catostomus warnerensis mostly from immature specimens, so that the proprtional measurements he presents are not representative of adults. The morphological description given below is based on Bond and Coombs (04) who presented the characteristics of 13 adults. Characteristics are also presented in Andreasen (01), Bond (02), and Schultz (17). Catostomus warnerensis is a small-eyed, "large-scaled" species with a conical snout. The dorsal fin base is short, its length equal to, or slightly less than, the depth of the head. Two or three rows of papillae cross the midline of the lower lip anterior to the incomplete cleft. The width of the fronto-parietal fontanelle is greater than one-half the diameter of the eye in adults. Dark pigmentation does not extend into the lower 1/3 of the body; it does not reach the pelvic or anal fins and, in adults, does not reach the upper lip. There is an unpigmented area around the front of the Taxonomy - 1 (DRAFT) - Taxonomy Species SUCKER, WARNER Species Id ESIS251016 Date 14 MAR 96 snout. Average or usual proportional measurements (in decimal fractions of standard length) follow: head length, 0.252; head depth, 0.157; depth of caudal peduncle, 0.089; diameter of eye, 0.031; snout length, 0.119; mouth width, 0.067; snout to dorsal, 0.498; length of dorsal, 0.498; length of dorsal base, 0.147. Counts of meristic and other enumerable characters follow (04): (presented as range followed by mean in parentheses) Fin rays - dorsal, 9-11 (10.23); anal, 7-8 (7.23); pectoral, 14-17 (15.61); pelvic, 9-11 (9.69). Scales - lateral line, 74-83 (78.08); above lateral line, 15-17 (15.83); lateral line to origin of anal 9-12 (11.08). Pigmentation of the dorsal surface is dark with heavy mottling, sometimes blotchy. Breeding males are almost uniformly dark on the dorsum. Most breeding adults show reddish color on the sides. This sometimes mixes with the dark mottling and can range from a slight wash of pink or copper to brilliant red or red-orange. The heavily colored males, with the black back, red sides and silvery white lower sides and belly, are pretty indeed. The synonymy of the species is straightforward. Cope (09) identified the species as Catostomus tahoensis (the Tahoe sucker) Gill and Jordan 1878, and applied that name in his 1884 article. Snyder and Gilbert (1897) listed Cope's C. tahoensis from Warner Lake in the synonomy of their newly described C. rimiculus although it was preceded by a question mark (08). Snyder (19) in 1908, based on 12 specimens obtained in 1897 and 1904, recognized the species as undescribed and named it Catostomus warnerensis. Subsequent authors have used that name. Schultz and DeLacy included Catostomus batrachops Cope 1884 in the synonymy with C. warnerensis, however, it appears that the intent in Cope 1884 (09) was to apply batrachops only to a fossil specimen from Silver Lake region. The type specimen of Catostomus warnerensis Snyder 1908 is U.S. National Museum No. 55597. Additional specimens are at the University of Michigan, UMMZ 130509, 130518 and 130519, and at Oregon State University, OS 761, 2440, 2710, 4315, 4566, 5140, 5148, 5256, 5257, 5288, 5311, 5410, 5412, 6358, 6359, 7032, 7035, 7051. Snyder (19) included a drawing of the holotype. A photograph may be found in Deacon, et al., 1979 (10) and there are transparencies and photographs on file at the Department of Fisheries and Wildlife, Oregon State University. Taxonomy - 2
                                  (DRAFT) - Status
                               Species SUCKER, WARNER
                                Species Id ESIS251016
                                   Date 14 MAR 96



STATUS

Coded Status T: Federal Threatened COMMENTS ON STATUS - U.S. STATUSES AND LAWS: The Warner sucker (Catostomus warnerensis) has been designated a Threatened species pursuant to the Endangered Species Act of 1973 (50 CFR 17.11; P.L. 93-205, 87 Stat. 884; 16 U.S.C. 1531-1540), as amended. The species has this status wherever found including the States of Nevada and Oregon. Critical Habitat has been designated in Lake County, Oregon, to include the stream and 50 feet on either side of the stream of aproximately 4 stream miles of Twelvemile Creek; 18 stream miles of Twentymile Creek; 2 stream miles of the spillway canal of Hart Lake; 3 stream miles of Snyder Creek; and about 16 stream miles of Honey Creek (50 CFR 17.95(e)). Special rules concerning "take" incidental too recreational fishing or for educational, scientific, or conservation purposes in accordance with applicable Oregon State laws or regulations for this species can be found in 50 CFR 17.44(l). This species is protected by the Lacey Act (P.L. 97-79, as amended; 16 U.S.C. 3371 et seq.) which makes it unlawful to import, export, transport, sell, receive, acquire, or purchase any wild animal (alive or dead including parts, products, eggs, or offspring): (1) in interstate or foreign commerce if taken, possessed, transported or sold in violation of any State law or regulation, or foreign law; or (2) if taken or possessed in violation of any U.S. law, treaty, or regulation or in violation of Indian tribal law. It is also unlawful to possess any wild animal (alive or dead including parts, products, eggs, and offspring) within the U.S. territorial or special maritime jurisdiction (as defined in 18 U.S.C. 7) that is taken, possessed, transported, or sold in violation of any State law or regulation, foreign law, or Indian tribal law. RESPONSIBLE FEDERAL AGENCIES: USFWS -Responsible for the management/recovery, listing, and law enforcement/protection of this species. BLM -Responsible for the law enforcement/protection of this species with applicable State and Federal laws on public land under their control (43 CFR 4140). Also responsible for management/recovery on Bureau of Land Management lands. Status - 1 (DRAFT) - Status Species SUCKER, WARNER Species Id ESIS251016 Date 14 MAR 96 USFS -Responsible for the law enforcement/protection of this species with applicable State and Federal laws on public lands under their control. Also responsible for management/recovery on Forest Service lands. The Forest Service is responsible for integrating management, protection, and conservation of Federally listed species into the Forest Planning process (36 CFR 219.19 and 219.20). Management practices that would cause detrimental changes in water temperature or composition, water course blockage, or sediment deposits within 100 feet of the edges of perennial streams, lakes or other bodies of water are prohibited (36 CFR 219.27(e)). All Federal agencies have responsibility to ensure that any action authorized, funded, or carried out by that agency is not likely to jeopardize the continued existence of the species or result in the destruction or adverse modification of Critical Habitat (50 CFR 402), and to utilize their authorities to carry out programs for the conservation of the species. STATE STATUSES AND LAWS: STATE: Oregon DESIGNATED STATUS: Threatened ADMINISTRATIVE AGENCY: Oregon Deaprtment of Fish and Wildlife STATE STATUTE: OR Administrative Rules, Chapter 635, Divison 7; Oregon Revised Statutes 496.002 - 498.029, 506.001 - 506.518, and 610.002 - 610.060. STATE: Nevada DESIGNATED STATUS: Recognized Threatened, under the state's full co-operative agreement with the U.S. Fish and Wildl. Service ADMINISTRATIVE AGENCY: NV Dept. of Wildlife STATE STATUTE: Nev. Admin. Code 503.015 to 503.080, Dec. 21, 1981 INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS: The Warner sucker is listed as Endangered in the IUCN Red List of Threatened Animals (1986). ECONOMIC STATUSES: None. 84/05/21:49 FR 21383/21383 - Proposed rule - Threatened w/ Crit. Hab. 85/09/27:50 FR 39117/39123 - Final rule - listed Threat. w/ Crit. Hab. Status - 2
     

HABITAT ASSOCIATIONS

HABITAT - AQUATIC INLAND AQUATIC LAND USE - Cropland and Pasture Herbaceous Rangeland Shrub and Brush Rangeland Mixed Rangeland Streams and Canals Lakes Reservoirs Nonforested Wetland Sandy Areas other than Beaches NATIONAL WETLAND INVENTORY CODES NWI NWICLS NWIMOD NWISPEC Riverine, upper perennial SB2 Riverine, upper perennial SB1 3FL Riverine, upper perennial FL1 Riverine, lower perennial FL4 Riverine, lower perennial FL3 Lacustrine, littoral RS2 Lacustrine, limnetic UB4 Lacustrine, limnetic UB3 Lacustrine, limnetic UB2 Lacustrine, limnetic UB1 Lacustrine, limnetic UB Lacustrine, limnetic OW0 Palustrine EM1 COMMENTS ON HABITAT ASSOCIATIONS - Large juvenile and adult Warner suckers have been collected in the following habitats: 1. turbid alkaline lakes and reservoirs with mixed types of shoreline (03,05,16,20,22); for instance, Hart Lake has rocky shoreline along the base of the Warner escarpment on the east and a combination of beaches and unconsolidated organic banks on the south and west. Much of the north shore consists of an earth dam. See Weide (21) for geomorphology; 2. irrigation and diversion canals with diked banks (15,16); 3. dredged canals in wetlands (15,16); 4. low gradient streams or stream sections (in uplands and lowlands) with mixed bottom types (06,15,16); 5. upland streams with gravel to boulder bottoms (15,16,20); and 6. spring areas with open water over sand and gravel bottom, as well as softer bottom with emergent vegetation (15,16). Some of the lowland habitats are adjacent to alfalfa fields or pasture, some are adjacent to alkali flat, dunes or rangeland (these lower rangelands are mainly sage to dry grassland areas). Others are in or adjacent to marshes and wet grasslands. The upland habitats are in rangeland (The upper rangelands differ from the lower in that they are denser in sage, and also contain juniper. As elevations increased these areas change to pinyon pines, and at this point the Warner sucker is not found in higher in elevations and cover types). Habitat Associations - 1 Apparently the preferred non-breeding habitat is slow or still water with moderate to high organic production. This combination is found in medium to large pools in creeks, in canals with slow current, reservoirs and lakes. Breeding habitat appears to be gravelly areas in streams or springs. Larval suckers seek still water at the edges of streams and ditches, where they can be found in water 1-3 inches deep (08). Most captures of Warner suckers have been from water ranging in temperature from 44 deg. F in early May to 64 deg. F in late May (16,24). In mid-June, suckers were taken in the slough below Hart Lake spillway at 81.5 deg. F (08). No details are available on requirements of the species for dissolved oxygen, pH or alkalinity, but it appears to be tolerant of high pH. Habitat Associations - 2
                                (DRAFT) - Food Habits
                               Species SUCKER, WARNER
                                Species Id ESIS251016
                                   Date 14 MAR 96



FOOD HABITS

TROPHIC LEVEL - OMNIVORE LIFESTAGE FOOD FOOD PART General Detritus General Diatoms General Algae General Zooplankton General Arthropods General Crustaceans Food Habits - 1
                         (DRAFT) - Environment Associations
                               Species SUCKER, WARNER
                                Species Id ESIS251016
                                   Date 14 MAR 96



ENVIRONMENTAL ASSOCIATIONS

G = General A = Adult LIM = Limiting RA = Resting Adult J = Juvenile FA = Feeding Adult RJ = Resting Juvenile BA = Breeding Adult FJ = Feeding Juvenile P = Pupae L = Larvae E = Egg RL = Resting Larvae FL = Feeding Larvae
LIFESTAGE ENVIRONMENTAL ASSOCIATIONS G G Aquatic Features: Pool areas G Aquatic Features: Springs [flowing] Environment Associations - 1
                               (DRAFT) - Life History
                               Species SUCKER, WARNER
                                Species Id ESIS251016
                                   Date 14 MAR 96



LIFE HISTORY

FOOD HABITS: The food habits of the Warner sucker have not been throughly studied, but are believed to be similar to others of the genus. Moyle (14) covers the food habits of the related species Catostomus occidentalis, C. tahoensis, and C. microps. These feed on algae (mostly diatoms), midge larvae, other small insects, zooplankton, and other small crustacea as well as organic debris. Suckers are mainly nocturnal in feeding (14). HOME RANGE/TERRITORY: No territoriality is known. Home range has not been studied. PERIODICITY: The species is nocturnally active, as indicated by trap net catches (20). Seasonal spawning migrations appear to be at least partly diurnal (08). MIGRATION PATTERNS: This is a migratory species that ascends streams for spawning from early spring to early summer. Most migrating individuals have been captured during late April and most of May (04,08). Because of dams that obstruct passage, and because some populations live in pools close to suitable spawning area, the known migrations are short, although without obstructions the species might be capable of migrations of several miles (24). COVER/SHELTER REQUIREMENTS: The species requires pools, lakes, or other still water for feeding and growth. Cover can be turbidity, depth, or boulders, etc. (08,16). Suckers apparently spend the fall and winter in lakes or deep portions of canals and creeks before migrating to gravel-bottomed areas in spring to spawn, as the water temperature reaches 8 deg. C (04). At about 30 mm length, juveniles leave the stream edges and move to deeper water (04). Young suckers apparently remain in creeks for several months to two years before descending to larger, more still waters (05,08). REPRODUCTIVE SITE REQUIREMENTS: Although spawning has not been observed, ripe and spent individuals have been taken from typical spawning areas - gravelly streams with moderate current (04,08). Captures have been mostly at temperatures ranging from 44-64 deg. F, although ripe individuals have been taken at 81.5 deg. F (08,20). REPRODUCTIVE CHARACTERISTICS: Breeding behavior has not been observed, but is thought to be similar to other Catostomus (see Moyle (14)). Minimum breeding age is three years, maximum is at least nine years (08). Breeding season is spring with one reproductive period per year (08). Typical sucker spawning usually involves one female attended by two or more males (14). Chances are good that the Warner sucker has the typical Life History - 1 (DRAFT) - Life History Species SUCKER, WARNER Species Id ESIS251016 Date 14 MAR 96 behavior. PARENTAL CARE: No parental care is known or suspected. Larvae have been collected on June 4 and postlarvae have been collected as late as July 23 on Snyder Creek. Post larvae ranged from 11 to 17 mm. Metamorphosed juveniles, 21 to 28 mm, appeared about 4 weeks following the appearance of postlarvae (June 8) on Honey Creek (04). POPULATION BIOLOGY: Population biology is little known, except that after a series of dry years the population appears to be very low. For instance, the District Fisheries Biologist (25) reported in 1963 that there were no suckers in Warner Valley to his knowledge. A few had been taken in 1954 and 1955 (16) and a few were found in 1963. Flows in Honey Creek, for instance, were low during the early 1960's, and were average to high during the late 1970's (08), thus allowing better access to spawning grounds and spreading water over a greater area. The longevity of the species, nine years or more, should allow individuals at least one successful spawning migration during a lifetime (07,08). Sex ratio observed in 163 individuals was 1.2 males to 1 female (08). SPECIES INTERRELATIONSHIPS: There is a possibility, not confirmed, that laregemouth bass, crappies, and brown bullheads prey on larval and juvenile suckers (07). OTHER LIFE HISTORY DESCRIPTORS: The average lengths of the Warner sucker are as follows (04): Age (in years): Length (mm): 1 40 2 80 3 130 4 160 5 210 6 250 7 300 8 330 *(The largest fish measured [age was not determined] was 372 mm [04]). Life History - 2
                           (DRAFT) - Management Practices
                               Species SUCKER, WARNER
                                Species Id ESIS251016
                                   Date 14 MAR 96



MANAGEMENT PRACTICES

RESULT MANAGEMENT PRACTICE Beneficial Restricting/regulating human disturbance of populations Beneficial Developing fishways Beneficial Developing/maintaining stream structures Beneficial Maintaining/Controlling Water Flow Beneficial Developing/maintaining/protecting wetlands Beneficial Land Acquisition Beneficial Reforestation Beneficial Controlling/Removing Exotic Vertebrates Beneficial Controlling/Removing Domestic Animals Adverse Predation Existing Predation Adverse Irrigating Existing Irrigating Adverse Reservoirs Existing Reservoirs Adverse Migration barriers Existing Migration barriers Adverse Dredging Existing Dredging Adverse Exotic/Feral/Introducted Species Existing Exotic/Feral/Introducted Species Adverse Existing COMMENTS ON MANAGEMENT PRACTICES - The present status of the Warner sucker is attributable to both natural and manmade causes. The desiccation of Pluvial Lake Warner (21,12) diminished the water areas in Warner Valley. Development of water control for agricultural purposes has reduced further the accessible waters. Storage dams, diversion dams, diversion ditches and irrigation canals throughout the system have stopped spawning migrations and diverted suckers into alfalfa fields and pastures, and have dewatered streams at peak seasons (03,06,07,08,22). The water control systems did not develop on an extensive basis until the late 1930's (13). Before that time, according to interviews with local residents, the suckers were numerous in the creeks (08). Damming of the stream habitat prevents access to spawning areas. Diversion of water allows larvae and adults to be led into fields with no access to suitable habitat (03,08,22). Predatory fishes (largemouth bass, crappie, and bullheads) have been introduced to the valley. These could have an adverse impact on the survival of larval and juvenile suckers since they may serve as a prey food base for these introduced species (07). Another possible threat is the development of geothermal resources (08). Management Practices - 1 (DRAFT) - Management Practices Species SUCKER, WARNER Species Id ESIS251016 Date 14 MAR 96 UNAPPROVED PLAN: At present, there is no formal recovery plan for the Warner sucker. Recommended recovery actions include: 1. Land acquisition to protect the limited distribution of this species (the drainages that this species inhabits include private lands, that should be acquired to insure protection of this species). 2. Protection of spawning sites (some located on private land holdings). 3. Control irrigation use. Irrigation ditches prevent movement of spawning adults upstream. Fry going downstream are diverted into the irrigated fields causing high losses. Fish passage devices will need to be installed for the spawning adults, and to prevent any further losses of fry, the addition of screens to off-take areas for irrigation will prevent fry from entering the irrigation lines. 4. A program needs to be undertaken for exotic predator control (i.e. removal of exotic crappie and sunfish). 5. Also to protect the habitat area, the following items will need to be undertaken: (a) addition of fenceing will limit human access, (b) habitat management to protect this riparian habitat (i.e., wetland management and modifications, maintainence of water flow, and stream bank modifacation and habitat revegetation (ex. replanting of willow along stream banks), and (c) the removal of cattle on these lands to prevent further vegetative damage, and soil erosion and sedimentation. Management Practices - 2
                                   (DRAFT) - References
                                  Species SUCKER, WARNER
                                  Species Id ESIS251016
                                      Date 14 MAR 96



     

References

***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE ***** 01 Anderson, J.K. 1976. Systematics and status of the family Catostomidae in southern Oregon. Ph.D. Thesis. OR State Univ. Corvallis. 76 pp. 02 Bond, C.E. 1973. Keys to Oregon freshwater fishes. OR Agric. Exp. Sta. Tech. Bull. 58. 42 pp. 03 Bond, C.E. 1974. Endangered plants and animals of Oregon: I. Fishes, Oregon Agric. Exp. Sta. Spec. Rept. 205. Pp. 1-9. 04 Bond, C.E., and C.Combs. 1985. Characteristics and life history of Catostomus warnerensis. Proc. Desert Fish. Counc. XIII:40-45. 05 Coombs, C.I. 1980. Observations on population status and reproduction of the Warner sucker (Catostomus warnerensis). Proc. Desert Fish. Counc. XI:87. 06 Coombs, C., and C.E. Bond. 1980. Report of investigations on Catostomus warnerensis. Fall 1979 and Spring 1980. Unpubl. rept. Dept. Fish. and Wildl., OR State Univ., Corallis. 29 pp. 07 Coombs, C.I., and C.E. Bond. 1981. Status of the Warner sucker (Catostomus warnerensis). Proc. Desert Fish. Counc. XII:76. 08 Coombs, C., C.E. Bond, and S.F. Drohan. 1979. Spawning and early life history of the Warner sucker (Catostomus warnerensis). Rept. to: U.S. Fish. and Wildl. Serv., Sacramento, CA. 52 pp. 09 Cope, E.D. 1884. On the fishes of the recent and pliocene lakes of the western part of the Great Basin, and Idaho Pliocene Lake. Proc. Acad. Nat. Sci. Philad. 35; 1883:134-166. 10 Deacon, J.E., G. Kobetich, J.D. Williams, S. Contreras, et al. 1979. Fishes of North America endangered, threatened, or of special concern: 1979. Fisheries 4(2):30-44. 11 Hayes, J. 1980. Fish of Warner Valley, Pp. 120-139. In: Dept. of Fish. and Wildl., Oregon State Univ., C. Gilman (ed.). Analysis of the aquatic habitats of Warner VAlley with relation to land use patterns. Final Rept. (Grant No. SPI-78-03490) to National Science Foundation. 12 Hubbs, C.L., and R.R. Miller. 1948. The zoological evidence/ correlation between fish distribution and hydrographic history in the desert basins of western United States. Bull. Univ. Utah 30(2) Pp. 17-166. 13 Hunt, J.H. 1964. The Warner Valley Stock Company - a geographic study. M.S. Thesis. OR State Univ., Corvallis. 116 pp. 14 Moyle, P.B. 1976. Inland fishes of California., Univ. of Calif. Press. 405 pp. 15 Oregon Natural Heritage Program. 1985. Fish data. Portland, OR. 16 Oregon State University. 1986. Oregon Fish Data Base: Warner sucker file. Dept. of Fish. and Wildl. OR State Univ., Corvallis. 17 Schultz, L.P. 1936. Keys to the fishes of Washington, Oregon, and closely adjoining regions. Univ. of Wash. Publ. in Bio. 2(4):103-228. 18 Schultz, L.P., and A.C. DeLay. 1935-1936. Fishes of the American Northwest. Jour. Pan Pac. Res. Inst. X(4) Mid Pacific Mag. 19 Snyder, J.O. 1908. Relationships of the fish fauna of the lakes References - 1 (DRAFT) - References Species SUCKER, WARNER Species Id ESIS251016 Date 14 MAR 96 of southwestern Oregon. Bull. U.S. Bur. Fish., vol. XXVII, 1907. Pp. 69-102. 20 Swenson, S.C. 1978. Report on investigation on Catostomus warnerensis during spring 1978. Report to U.S. Fish and Wildl. Serv., Sacramento, CA. 27 pp. 22 U.S. Fish and Wildlife Service. 1985. Endangered and Threatened wildlife and plants; determination that Warner sucker is a threatened species and designation of its critical habitat. Fed. Reg. 50(188):39117-39123. 23 Bond, C.E. 1978. [Letter to Dr. James Williams, Office of Endangered Species, USFWS, Washington, D.C.] 24 Bond, C.E. [n.d.]. Pers. obs. and pers. know. OR State Univ., Corvallis. 25 District Fisheries Biologist. 1963. Pers. comm. OR Dept. of Fish. and Wildl., Lakeview. ***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY ***** 01 Bond, C.E. 1974. Endangered plants and animals of Oregon: I. Fishes, Oregon Agric. Exp. Sta. Spec. Rept. 205. Pp. 1-9. 02 Coombs, C., and C.E. Bond. 1980. Report of investigations on Catostomus warnerensis. Fall 1979 and Spring 1980. Unpubl. rept. Dept. Fish. and Wildl., OR State Univ., Corvallis. 29 pp. 03 Coombs, C., C.E. Bond, and S.F. Drohan. 1979. Spawning and early life history of the Warner sucker (Catostomus warnerensis). Rept. to: U.S. Fish and Wildl. Serv., Sacramento, CA. 52 pp. 04 Coombs, C., S. Drohan, and C.E. Bond. 1979. Spawning and early life history of the Warner sucker. Quarterly Prog. Rept. to: USFWS, Sacramento, CA. 7 pp. 05 Cope, E.D. 1884. On the fishes of the recent and pliocene lakes of the western part of the Great Basin, and Idaho Pliocene Lake. Proc. Acad. Nat. Sci. Philad. 35; 1883:134-166. 06 Hayes, J. 1980. Fish of Warner Valley, Pp. 120-139. In: Dept. of Fish. and Wildl., Oregon State Univ., C. Gilman (ed.). Analysis of the aquatic habitats of Warner VAlley with relation to land use patterns. Final Rept. (Grant No. SPI-78-03490) to National Science Foundation. 07 Oregon State University. 1986. Oregon Fish Data Base: Warner sucker file. Dept. of Fish. and Wildl., OR State Univ., Corvallis. 08 Schultz, L.P., and A.C. DeLay. 1935-1936. Fishes of the American Northwest. Jour. Pan Pac. Res. Inst. X(4) Mid Pacific Mag. 09 Snyder, J.O. 1908. Relationships of the fish fauna of the lakes of southwestern Oregon. Bull. U.S. Bur. Fish., vol. XXVII, 1907. Pp. 69-102. 10 Swenson, S.C. 1978. Report on investigation on Catostomus warnerensis during spring 1978. Report to U.S. Fish and Wildl. Serv., Sacramento, CA. 27 pp. 11 U.S. Fish and Wildlife Service. 1985. Endangered and Threatened wildlife and plants; determination that Warner sucker is a threatened species and designation of its critical habitat. Fed. Reg. 50(188):39117-39123. References - 2 (DRAFT) - References Species SUCKER, WARNER Species Id ESIS251016 Date 14 MAR 96 12 Williams, J.E. Pers. observ. 1987. Sacramento, CA 95825. References - 3