(DRAFT) - Taxonomy
                                Species SUCKER, MODOC
                                Species Id ESIS251011
                                   Date 14 MAR 96



TAXONOMY

NAME - SUCKER, MODOC OTHER COMMON NAMES - SUCKER and MODOC 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 - MICROPS, SCIENTIFIC NAME - CATOSTOMUS MICROPS AUTHORITY - TAXONOMY REFERENCES - COMMENTS ON TAXONOMY - Modoc Sucker Catostomus microps Rutter, 1908 KINGDOM: Animal GROUP: Fish PHYLUM: Chordata CLASS: Osteichthyes ORDER: Cypriniformes FAMILY: Catostomidae Catostomus microps is a small (SL to 190 mm) sucker with small eyes (2-6 mm diam.), located in the middle of the head (01). Scales are fine: scales in lateral line, 80-89; scales above lateral line, 15-19; scales below lateral line, 9-12 (01,02). Its low dorsal ray count (10-11, sometimes 12), distinguishes it from most other Catostomus spp. in California. Other ray counts are as follows: anal, 7; pelvic, 8-10; pectoral, 13-17; caudal, 18-19 (01, 02). Gill rakers range from 18-26 (01,02). Lips are moderate, with 2 rows of papillae (infrequently 3-4) upper lip only slight (if present) notches between upper lip and lower lip, a deep medial notch on lower lip, separated from the cartilaginous sheath of the lower jaw by 1-2 continuous rows of papillae (01,02). The frontanelle on the top of the head is closed, or nearly so (03). Axillary process is absent from pelvics (01,03). The back of the Modoc sucker is from deep gray to bluish greenish Taxonomy - 1 (DRAFT) - Taxonomy Species SUCKER, MODOC Species Id ESIS251011 Date 14 MAR 96 brown (01,03). Sides lighten to yellow or white on the belly (01,03). Caudal and paired fins are light yellowish-orange (01). There are three dark spots along the sides near the lateral line (01). Breeding males develop some color in lateral stripe and some tubercles, but not to the same extent as do males (04,05). There are no other scientific names for the Modoc sucker. Its scientific nomenclature has never been subject to change or question (08). Three type specimens of Modoc sucker were collected in 1898 by Rutter and Chamberlain (Type no. 58496, U.S. National Museum) (06). Hubbs collected 27 more in 1934 (UMMZ#130643) (07). Detailed descriptions of the Modoc sucker can be found in Rutter 1908 (05, with figures), Miller 1961, (07), Martin 1972 (01), Moyle 1976 (03, with figure), and Ford 1977 (02). Taxonomy - 2
                                  (DRAFT) - Status
                                Species SUCKER, MODOC
                                Species Id ESIS251011
                                   Date 14 MAR 96



STATUS

Coded Status E: Federal Endangered COMMENTS ON STATUS - U.S. STATUSES AND LAWS: The Modoc sucker (Catostomus microps) has been designated an Endangered 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 State of California. Critical Habitat has been designated in intermittent and permanent water and adjacent land areas that provide vegetation for cover and protection from soil erosion of all or portions of: Turner Creek, Hulbert Creek, Cedar Creek, Washington Creek, Coffee Mill Gulch, Johnson Creek, Higgins and Rice Flats, and Rush Creek, Modoc County, CA (50 CFR 17.95(e)). 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 (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. 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 Status - 1 (DRAFT) - Status Species SUCKER, MODOC Species Id ESIS251011 Date 14 MAR 96 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: California DESIGNATED STATUS: Endangered ADMINISTRATIVE AGENCY: (CA) Department of Fish and Game STATE STATUTE: (CA) Endangered Species Act; Fish and Game Code Chapt. 1.5, Art. 1, Sect. 2050. INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS: The Modoc Sucker is listed as rare in the IUCN Red Data Book, vol. 4, 1977. ECONOMIC STATUSES: None. 83/06/14:48 FR 27273/27274 - Proposed listing. 85/06/11:50 FR 24526/24530 - Listed Endangered with Critical Habitat Status - 2
     

HABITAT ASSOCIATIONS

HABITAT - AQUATIC INLAND AQUATIC SOCIETY OF AMERICAN FORESTRY TYPES SAF TYPE STAGE CLOSURE Interior Ponderosa Pine mature tree LAND USE - Residential Cropland and Pasture Orchards, Groves, Vineyards, Nurseries, Mixed Rangeland Evergreen Forest Land Streams and Canals Reservoirs Forested Wetland Nonforested Wetland NATIONAL WETLAND INVENTORY CODES NWI NWICLS NWIMOD NWISPEC Riverine, intermittent UB3 Riverine, intermittent UB2 Riverine, intermittent UB1 Riverine, intermittent SB3 Riverine, intermittent SB2 Riverine, intermittent SB1 Riverine, intermittent OW0 Riverine, intermittent OW0 Riverine, intermittent FL6 Riverine, intermittent AB2 4AB Riverine, lower perennial UB3 Riverine, lower perennial UB2 Riverine, lower perennial UB1 Riverine, lower perennial OW0 Riverine, lower perennial OW0 Riverine, lower perennial FL6 Riverine, lower perennial AB2 Riverine, lower perennial AB1 Palustrine SS1 Palustrine FL1 Palustrine EM1 COMMENTS ON HABITAT ASSOCIATIONS - Historically the region where the Modoc sucker is found is in a land of volcanic activity (02). The drainages are characterized by mountain meadows and valleys lying between parallel mountain ranges of volcanic history (03). Annual precipitation at the lowest elevation ranges around 40 cm, 25% of which is snow, with higher levels found at higher elevations (02). The Modoc sucker occurs primarily in sections of stream with low or intermittent flow, or pools of the meadowlands (02,03,14). Vegetation in valleys and meadow grasslands are covered with sagebrush (Artemisia tridentata) and western juniper (Juniperus occidentalis) (08). Forested areas are mostly ponderosa pine (Pinus ponderosa), Habitat Associations - 1 Jeffery pine (Pinus jeffreyi), California black oak (Quercus kelloggii), California incense cedar (Libocedrus decurrens), and white fir (Abies concolor) (08). Riparian vegetation occurs in scattered remnant areas, and is comprised of black cottonwood (Populus trichocarpa), quaking aspen (P. tremuloides), willows (Salix spp.), and tall grasses, all of which provide cover (02). In general, sites where Modoc suckers have been found are characterized by the following: low flows (intermittent in some); largely shallow pools; muddy bottoms; partial shade trees, shrubs, boulders, or undercut banks; abundant cover from riparian vegetation and undercut banks; and moderately clear water (14). Portions of the Modoc sucker habitat in Rush Creek run through a small residential subdivision, farmland (irrigated fields of hay and alfalfa) and pasture. A Christmas tree farm is adjacent to the Johnson Creek population. Possible populations may occur in association with Moon Lake and Dorris Reservoir. Specifically, Modoc suckers on the average were found in streams with the following conditions (mean +/- s.d.): elevation, 1,382.00 (+/- 79.00 m); average depth, 0.44 m (+/- 0.31 m); maximum depth, 063 m (+/- 0.63 m); width, 2.92 m (+/- 1.57 m); flow, 113.26 (+/- 83.81 l/sec); turbidity (ranked 1-5), 2.50 (+/- 0.60); aquatic vegetation, 7% of area (+/- 15%); pools, 62% of area (+/- 35%); riffles, 33% 0f area (+/- 3%); substrate of 30% of mud (+/- 30%), 11 pct. sand (+/- 14%), 25% rubble (+/- 25%), 8% boulder (+/- 17%); and 19-28% shade (14). Water temeratures (summer and fall) range from 7.8 deg. Celsius (fall) to 23.3 deg. Celsius (summer) (02). Water chemistry is as follows: pH ranges from 7.0-9.0; dissolved oxygen, 10-16 mg/l; NaCl, 12.5-25.0 mg/l; Cl, 7.6-15.2 mg/l; total alkalinity (as CaCO3), 76-235 mg/l; total hardness (as CaCO3), 68-222 mg/l (02). Spawning, observed only in Johnson Creek, occurs over coarse fine gravel in the lower end of pools with abundant cover. Water temperatures range from 13.3-16.1 deg. Celsius (04). There is some evidence from Johnson and Washington Creeks of upstream migration by Modoc suckers to small intermittent tributaries, such as Higgins and Rice Flats, during spawning season (04). Also, a possible spawning migration of Modoc suckers has been observed from Moon (Lake) Reservoir upstream into Cedar Creek, but conclusive identification of the suckers has not been determined (02). Year-round studies of habitat usage and more studies of spawning behavior need to be accompished to describe fully the required habitat of the Modoc sucker. Determinations of physiological limitations also need to be performed before further speculation on preferred habitat can be made. The extent of habitat destruction in the past makes such speculation difficult. Habitat Associations - 2
                                (DRAFT) - Food Habits
                                Species SUCKER, MODOC
                                Species Id ESIS251011
                                   Date 14 MAR 96



FOOD HABITS

TROPHIC LEVEL - OMNIVORE LIFESTAGE FOOD FOOD PART General Detritus General Diatoms General Algae General Arthropods General Crustaceans Food Habits - 1
                         (DRAFT) - Environment Associations
                                Species SUCKER, MODOC
                                Species Id ESIS251011
                                   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 Environment Associations - 1
                               (DRAFT) - Life History
                                Species SUCKER, MODOC
                                Species Id ESIS251011
                                   Date 14 MAR 96



LIFE HISTORY

FOOD HABITS: The diet of the Modoc sucker comprises the following volume: detritus, 47%; diatoms, 19%; filamentous algae, 10%; chironomid larvae, 18%; crustaceans, 4% (mostly amphipods and cydorid cladocerans); and aquatic insect larvae, 2% (mostly tricopteran larvae) (14). This omnivorous diet is typical of suckers of the genus Catostomus, and the food items are characteristic flora and fauna of pools. Adult suckers usually remain on the bottom or close to it (01). This and the morphological features of having an anal fin that can be folded so as to not interfere with substrate contact, large numbers of papillae and taste buds on the downward turned mouth, limited eyesight, and the position of the eyes in the middle of the head are all indicators of bottom feeding habits (01). Determinations of different diets for the different life stages or during different seasons have not yet been made. Studies comparing preferred foods with available foods have not been made. However, insects and crustaceans are assumed to be preferred food items based on the typical diet of suckers (Catostomus). HOME RANGE/TERRITORY: The Modoc sucker is gregarious at all ages, being found in large groups in pools (02,15). Even during spawning no territoriality or aggressive behavior has been observed (04). There is no information available on home ranges, but during the summer months the fish probably are confined to single pools or short sections of stream (13). PERIODICITY: Except with respect to spawning behavior, much information is not available on periodicity of activity of the Modoc sucker. However, the Modoc has been noted feeding diurnally (02,14). Spawning usually occurs from mid-April to the last week in May or first week in June (04). Spawning activity has been observed from mid-morning to late afternoon (04). MIGRATION PATTERNS: There is some evidence from Johnson and Washington Creeks of upstream migration by Modoc suckers to small intermittent tributaries during spawning season, which goes from mid-April to the last week in May or the first week on June (04). These spawning migrations, 0.5-1.5 km in length, may depend on temperature and water quality, although more information needs to be obtained on the relationship between water conditions and fish movements (04). Movements of fry to the main stream of the creeks have not been recorded. A possible spawning migration of Modoc suckers has been observed from Moon (Lake) Reservoir upstream into Cedar Creek, but conclusive identification of the suckers has not been determined (02). COVER/SHELTER REQUIREMENTS: Modoc suckers require cover to avoid avian, aquatic, and Life History - 1 (DRAFT) - Life History Species SUCKER, MODOC Species Id ESIS251011 Date 14 MAR 96 terrestrial predators (02). Deep pools (over 50 cm) provide cover from kingfishers (Ceryle alcyon) and herons (Ardea herodias) (13). Cover along the edges comes from undercut banks (08,13) and riparian vegeation of black cottonwood (Populus trichocarpa), quaking aspen (P. tremuloides), and especially willows (Salix spp.), grasses, rushes, and sedges, plus overhanging branches and roots (02). Logs and boulders washed into the creeks also provide cover (02,10,13). REPRODUCTIVE SITE REQUIREMENTS: Spawning sites of Modoc suckers have so far been identified only in pools of tributaries to Johnson Creek and Washington Creek (04). Flows in the pools were low (42-57 l/sec) (04). Pool depths averaged from 0.46-0.61 m (04). The substrate of the spawning site in the pool comprised 60-70% fine gravel (0.25-2.5 cm); 0-10% large gravel (2.5-7.4 cm); and 20-40% sand, silt, and detritus (04). Water temperatures at time of observed spawning ranged from 13.3-20.5 deg. Celsius (04). Water chemistry of the pools is as follows: pH ranged from 8.0-8.5; dissolved oxygen, 11-12 mg/l; dissolved CO2, 10-15 mg/l; alkalinity, 68-86 mg/l; hardness, 86 mg/l; Cl-, 15.5 mg/l; and NaCl, 25 mg/l (04). Spawning was observed in the lower end of the pools (04). Poolside cover consisted of grasses, undercut banks, rushes, sedges, junipers, and willows (04). REPRODUCTIVE CHARACTERISTICS: Spawning season of the Modoc sucker is from mid-April to the last week of May or first week of June (04). Sexual maturity in both sexes appears to occur at age 3, although some precocious 2 year old males have been found (14). Maximum breeding age is assumed to coincide with life expectancy, which is age 4, the oldest specimen caught being age 5 (03). Fecundities appear to be high for the size of the female: 6395 and 12,590 in two females, 162 and 165 mm SL, respectively (04). When spawning, one female is surrounded by 2-3 males, then they all vibrate their bodies for 6-8 second intervals during which milt and eggs are released and assumed to adhere to gravel (04). Males may stimulate females with breeding tubercles (04). Spawning has been observed from mid-morning to late afternoon (04). The period of fry emergence has not been determined. PARENTAL CARE: No parental care is exhibited by any member of the family Catostomidae (13). Nothing is known about the early life history of Modoc suckers untill fish 10-15 mm long are observed in the same pools as adult suckers, feeding on the bottom (13). Larvae probably occur in shallow water among emergent vegetation (13). POPULATION BIOLOGY: Current limiting factors to Modoc sucker populations (in streams from Sacramento suckers [Catostomus occidentalis] are excluded) are probably predation, spawning habitat, and cover for adults, especially large pools (02,13). Average life expectancy is 4 years, with the oldest specimen collected being 5 years old (03). Other parameters of population biology have not been determined. Life History - 2 (DRAFT) - Life History Species SUCKER, MODOC Species Id ESIS251011 Date 14 MAR 96 SPECIES INTERRELATIONSHIPS: Probable predators of the Modoc sucker are: the belted kingfisher (Megaceryle alcyon) (02), great blue heron (Ardea herodias) (02), garter snakes (Thamnophis elegans elegans, Thamnophis sirtalis, presumably on young) (02), brown trout (Salmo trutta) (05,14), pit sculpin (Cottus pitensis, presumably on young) (14), Sacramento squawfish (Ptychocheilus grandis, infequently found) (09). Brown trout are an introduced species and the only species for which the Modoc suckers have been documented as part of the diet (13). Identfied prey animals are chironmid larvae, amphipods, chydorid cladocerans, and tricopteran larvae (14). Identified external parasites are anchor worms (Lernaea cyprinacea) and "black spot" trematode (Strigeidae sp. or spp.) (02). The Sacramento sucker (Catostomus occidentalis) hybridizes with the Modoc sucker (02), and may be a competitor for spawning sites and food. Speckled dace (Rhinichthys osculus) are always abundant in Modoc sucker areas and may offer some competition for food and cover to young suckers, but may also serve as a "buffer species" for predators. Other fish species commonly found with Modoc suckers are: pit sculpin (Cottus pitensis), redband trout (Salmo sp.), California roach (Hesperoleucus symmetricus), rainbow trout (Salmo gairdneri), and, rarely, hardhead (Mylopharadon conocephalus). Yellow-legged frogs (Rana boylii) are common as both adults and tadpoles in Modoc sucker streams. However, none of these species are known to interact with Modoc suckers in any significant fashion (13,14). OTHER LIFE HISTORY DESCRIPTORS: Even in areas where they are abundant, Modoc suckers seldom dominate the fish fauna (14). It should be emphasized again that the population of suckers seen in Cedar Creek and Moon Reservoir have not been positively identified as being Modoc suckers. Initial meristic counts suggest that they are Modoc suckers (13), but the possibility of suckers being either hybrids (Modoc sucker x Sacramento sucker) or tahoe suckers (Catostomus tahoensis) still exists (13). Life History - 3
                           (DRAFT) - Management Practices
                                Species SUCKER, MODOC
                                Species Id ESIS251011
                                   Date 14 MAR 96



MANAGEMENT PRACTICES

RESULT MANAGEMENT PRACTICE Beneficial Regulating Water Temperature Beneficial Developing/maintaining stream structures Beneficial Maintaining/Controlling Water Flow Beneficial Developing/maintaining/protecting wetlands Beneficial Controlling water levels Beneficial Controlling/Restricting Road Maintainance Actions Beneficial Land Acquisition Beneficial Controlling/Restricting Agricultural Practice Beneficial Reforestation Beneficial Restricting Timber Harvest Beneficial Transplanting wild animals Beneficial Controlling/Removing Exotic Vertebrates Beneficial Controlling/Removing Domestic Animals Adverse Low Gene Pool Existing Low Gene Pool Adverse Hybridization Existing Hybridization Adverse Predation Existing Predation Adverse Soil compaction by heavy equipment in mine areas Existing Soil compaction by heavy equipment in mine areas Adverse Siltation Existing Siltation Adverse Flooding Existing Flooding Adverse Irrigating Existing Irrigating Adverse Dredging Existing Dredging Adverse Developing/maintaining stream bank vegetation Existing Developing/maintaining stream bank vegetation Adverse Exotic/Feral/Introducted Species Existing Exotic/Feral/Introducted Species Adverse Erosion Existing Erosion Adverse Grazing Existing Grazing Adverse Existing Adverse Vegetation Composition Changes Existing Vegetation Composition Changes COMMENTS ON MANAGEMENT PRACTICES - The Modoc sucker is endangered because of its very restricted distribution combined with destruction of habitat, including destruction of natural barriers to other Catostomus spp. Modoc suckers are known from only a few widley separated tributary systems to the upper Pit River: the Rush-Ash Creek system and the Washington- Management Practices - 1 (DRAFT) - Management Practices Species SUCKER, MODOC Species Id ESIS251011 Date 14 MAR 96 Turner-Hulbert system (02,03). Road construction and channelization of Rush Creek in 1966, and subsequently, has caused habitat loss through elimination of pools and cover resulting in reduced numbers of fish and biomass (05,09,10,11). A major portion of the Rush Creek Modoc sucker habitat is on privately owned land used for grazing sheep and cattle, which trample streambanks, thereby causing destruction of habitat through increased erosion of streambanks, ingestion of aquatic and riparian vegetation needed as cover, and siltation (03,05,08,11, 12). Destruction of natural barriers to the Sacramento sucker (C. occidentalis) by flooding areas for the creation of pastures, and by channelization, has resulted in losses through hybridization and backcrossing in several of the Modoc sucker streams (02,05,08,11,12, 13). Diversions of water for irrigation reduce the number and sizes of pools available to the Modoc suckers (02). Introductions of brown trout (Salmo trutta) have added to the predation pressure on the Modoc sucker (05,08,11,13). Destruction of habitat due to overgrazing and limited distribution of pure populations of the Modoc sucker still threaten the species (02,12). Continued habitat destruction due to overgrazing, reduced water for pools, and further hybridization result in low population numbers and a reduction in the gene pool for pure population and are the future threats to the Modoc sucker. UNAPPROVED PLAN: U.S. Fish and Wildlife Service. 1983. An Action Plan for Recovery of the Modoc Sucker (Catostomus microps). U.S. Fish and Wildl. Serv., Sacramento, CA. 14 pp. A modoc sucker recovery team has been formed to facilitate recovery of this endangered species. The team is comprised of representatives from: the Modoc National Forest, California Dept. of Fish and Game, U.S. Fish and Wildlife Service and the U.S. Soil Conservation Service. The action plan developed by this group is not considered an "official" approved recovery plan, but it is serving as a base structure for recovery and delisting of this species. Recovery actions are such that they fall under two main objectives: (1) protection of existing populations and (2) establishment of at least two additional populations. A break down of actions are as follows: Objective (1) - Protection of existing populations by: 1. Reduction of timber sales in and around sucker habitat. 2. Habitat revegetation and land rehabilitation. 3. Control and restriction of agricultural practices (causing siltation). 4. Control and restriction of road maintenance actions. 5. Maintenance of the water table and flow. 6. Wetland management and modification. 7. Stream bank/channel modification. 8. Control and removal of exotic brown trout. 9. Control and removal of cattle which have caused damage to Management Practices - 2 (DRAFT) - Management Practices Species SUCKER, MODOC Species Id ESIS251011 Date 14 MAR 96 surrounding habitat by over-grazing. Objective (2) - Establishment of two additional populations by: 1. Land acquistion (mainly private land Johnson and Dutch Flat Creeks). 2. Fencing and bank stabilization along Dutch Flat Creek. 3. Transplantation of wild individuals to Johnson and Dutch Flat Creeks. Recent recovery actions have included: (1) removal of Sacramento sucker from Turner Creek, (2) installation of fish barriers on Turner and Johnson Creeks, (3) fencing and reduction of cattle grazing along Washington and Johnson Creeks, and (4) monitoring of populations. Management Practices - 3
                                   (DRAFT) - References
                                  Species SUCKER, MODOC
                                  Species Id ESIS251011
                                      Date 14 MAR 96



     

References

***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE ***** 01 Martin, M. 1972. Morphology and variation of the Modoc sucker, Catostomus microps Rutter, with notes on feeding adaptations. Calif. Fish and Game 58(4):277-284. 02 Ford, T. 1977. Status summary report on the Modoc sucker (Catostomus microps Rutter). Unpubl. rpt. Modoc Nat. For., 45 pp. 03 Moyle, P. 1976. Inland Fishes of California. Univ. of Calif. Press, Berkeley. 405 pp. 04 Boccone, V., and T. Mills. 1979. Spawning behavior and spawning substrate preference of the Modoc sucker, Catostomus microps (Rutter). Inland Fish. End. Spec. Prog. Special Publ. 79-2, Calif. Dept. of Fish and Game. 33 pp. 05 Cooper, J.J., D.L. Koch, and E.L. Lider. 1978. A fishery investigation of the Modoc sucker (Catostomus microps) and the rough sculpin (Cottus asperrimus) in the Pitt River drainage between Turner Creek and Juniper Creek, Lassen and Modoc Counties, California. Univ. of Nev., Desert Res. Inst., Biores. Center Publ. No. 50002, 76 pp. 06 Rutter, C. 1908. The fishes of the Sacramento-San Joaquin basin, with a study of their distribution and variation. Bull. U.S. Bur. Fish. 27(637):103-152. 07 Miller, R. 1961. Man and the changing fish fauna of the American southwest. Pap. Mich. Acad. Sci., Arts and Letters. 46:365-404. 08 Mills, T.J. 1980. Life history, status, and management of the Modoc sucker, Catostomus microps (Rutter) in California, with a recommendation for endangered classification. Calif. Dept. of Fish and Game, Inland Fish. End. Spec. Prog., Spec. Publ. 80-6. 35 pp. 09 Miller, R. 1969. Freshwater fishes. In: Survival Serv. Comm. Red Data Book, 4-Pisces. IUCN, Morges, Switzerland, pp. 55-56. 10 Moyle, P. 1976. Some effects of channelization on the fishes and invertabrates of Rush Creek, Modoc County, California. Calif. Fish and Game 62(3):179-186. 11 Cooper, J.J. 1983. Distributional ecology of native and introduced fishes of the Pit River system, Northeastern California, with notes on the Modoc sucker. Calif. Fish and Game 69(1):39-53. 12 Chesney, W. 1985. A report to the Modoc sucker management team concerning Modoc sucker identification problems. Unpubl. rept. Calif. Dept. Fish and Game. 11 pp. 13 Moyle, P. 1975. Pers. comm. Dept. of Wildl. and Fish. Biol. Univ. of Calif., Davis. 95616. 14 Moyle, P. and A. Mariochi. 1975. Biology of the Modoc sucker, Catostomus microps, in norteastern California. Copeia 3:556-560. 15 Moyle, P. 1974. Status of the Modoc sucker (Catostomus microps) Pisces: Catostomidae. Cal-Neva Wildlife. pp. 35-38. ***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY ***** References - 1 (DRAFT) - References Species SUCKER, MODOC Species Id ESIS251011 Date 14 MAR 96 01 Moyle, P. 1973. Field notes. Dept. of Wildl. and Fish. Biol., Univ. of Calf., Davis. 02 Boccone, V., and T. Mills. 1979. Spawning behavior and spawning substrate preference of the Modoc sucker, Catostomus microps (Rutter). Inland Fish. End. Spec. Prog. Spec. Publ. 79-2, Calif., Dept. of Fish and Game. 33 pp. 03 Ford, T. 1977. Status summary report on the Modoc sucker (Catostomus microps Rutter). Unpubl. rept. Modoc Nat. For. 45 pp. 04 Moyle, P. 1975. Field notes. Dept. of Wildl. and Fish. Biol. Univ. of Calif., Davis. 05 Csuti, B. Correspondence September 3,1983., [To: Peter Moyle, Dept. of Fish and Game, Nat. Diversity Data Base, Planning Branch, Sacramento, CA 95814]. 06 Moyle, P. 1975. Pers. comm. Dept. of Wildl. and Fish. Biol. Univ. of Calif., Davis. 07 Williams, J. 1986. Pers. comm. End. Spec. Prog., U.S. Fish and Wildl. Serv., Sacramento, CA 95825. References - 2