Species Profile
Environmental Conservation Online System

Modoc Sucker (Catostomus microps)

Kingdom: Animalia
Class: Actinopterygii
Order: Cypriniformes
Family: Catostomidae

Listing Status:   

General Information

Modoc suckers are small, usually less than 6 inches (16 cm) standard length, with short heads and small eyes (Moyle 2002). Maximum size is 11 inches (28 cm). Lateral line scales number 73-91. Scales above the lateral line number usually number 15 (range = 14-19); those below the lateral line number 9-12. Dorsal fin rays number 9-12; anal fin rays 7; pelvic fins 8-10 (Kettratad 2001, Moyle 2002). The lower lip is deeply notched, with only one of the 5-6 rows of papillae connecting the two haves (Moyle 2002). The non-breeding color of both sexes is greenish-brown through bluish to deep-grey and olive, and the sides are lighter with generalized mottling and usually with 3-4 darker blotches, and is similar to Sacramento suckers of similar size. The belly is white to cream or yellowish and unmarked. Breeding males have a reddish-orange lateral band, and orange fins; tubercles develop on fins and body.

Lead Region:  California/Nevada Region (Region 8)
Date Listed: Jun 11, 1985

» Federal Register Documents

Most Recent Federal Register Documents (Showing 5 of 6 : view all)
Date Citation Page Title
03/22/2006 71 FR 14538 14542 Initiation of 5-Year Reviews of 56 Species in California and Nevada: Notice of review.
06/11/1985 50 FR 24526 24530 Determination of End. Status & Crit. Hab. for Modoc Sucker; 50 FR 24526- 24530
07/13/1984 49 FR 28583 28585 Notice of Finding on 6 Petitions; 49 FR 28583-28585
01/31/1984 49 FR 3892 3895 Proposed End. Status & Crit. Hab. for Modoc Sucker (Catostomus microps); 49 FR 3892-3895
06/14/1983 48 FR 27273 27274 Findings on Certain Petitions; 48 FR 27273-27274

» Recovery

Recovery Plan Information Search
Other Recovery Documents (Showing 1 of 1 )
Date Citation Page Title Document Type
03/22/2006 71 FR 14538 14542 Initiation of 5-Year Reviews of 56 Species in California and Nevada: Notice of review.
  • Notice 5-year Review
  • Five Year Review
    Date Title
    08/17/2009 Modoc Sucker 5-Year Review

    » Critical Habitat

    Current Critical Habitat Documents (Showing 2 of 2 )
    Date Citation Page Title Document Type Status
    06/11/1985 50 FR 24526 24530 Determination of End. Status & Crit. Hab. for Modoc Sucker; 50 FR 24526- 24530 Final Rule Active
    01/31/1984 49 FR 3892 3895 Proposed End. Status & Crit. Hab. for Modoc Sucker (Catostomus microps); 49 FR 3892-3895 Proposed Rule Not Required

    To learn more about critical habitat please see http://criticalhabitat.fws.gov

    » Conservation Plans

    No conservation plans have been created for Modoc Sucker

    » Petitions

    Most Recent Petition Findings (Showing 2 of 2 )
    Date Citation Page Title Finding
    07/13/1984 49 FR 28583 28585 Notice of Finding on 6 Petitions; 49 FR 28583-28585
  • Notice 12 month petition finding, Warranted
  • 06/14/1983 48 FR 27273 27274 Findings on Certain Petitions; 48 FR 27273-27274
  • Notice 90-day Petition Finding, Substantial
  • » Life History

    Habitat Requirements

    Modoc suckers are primarily found in mud and rock bottom pools in small streams and occupy an intermediate zone between the high-gradient and higher elevation, coldwater trout zone and the low-gradient and low elevation, warm-water fish zone (Reid 2008). The elevational range of the Modoc sucker is from about 4,200 to 5,000 feet in the upper Pit River drainage (Ash and Turner Creeks) and from about 4,700 to 5,800 feet in the Goose Lake sub-basin (Reid 2008). Cover consists of overhanging banks, larger rocks, woody debris, and aquatic rooted vegetation or filamentous algae. Larvae occupy shallow, vegetated margins and juveniles tend to remain free-swimming in the shallows of large pools, particularly near vegetated areas, while larger juveniles and adults remain mostly on, or close to, the bottom (Moyle and Marciochi 1975).

    Food Habits

    Modoc suckers feed on algae, aquatic insects, and small crustaceans found in mud or in algal filaments (Moyle 2002). Chironomid (midge) larvae may be especially important in the diet, but the jaw structure suggests specializations for scraping algae from rocks.

    Movement / Home Range

    Modoc suckers likely do not move large distances but do move upstream to spawn and move downstream when water levels drop in summer.

    Reproductive Strategy

    Both sexes mature in their third year at a length of about 5 inches (12 cm; Moyle 2002). Spawning occurs in gravel at the lower end of pools or in riffles in small tributaries, including those that are intermittent, from mid-April to early June when water temperatures are 56 to 61°F (13-16 °C). Several males position themselves on each side of the female and eggs and sperm are released. The fertilized eggs fall into the gaps in the gravel. Females produce up to 12,000 eggs per season (Moyle 2002).

    Other

    A greater understanding of the genetic relationships and natural gene flow between the Modoc sucker and Sacramento sucker has reduced concerns over hybridization between the two species (Reid 2008; USFWS 2009). The most significant threat to the Modoc sucker is nonnative predatory fish, especially largemouth bass and brown trout.

    » Other Resources

    NatureServe Explorer Species Reports -- NatureServe Explorer is a source for authoritative conservation information on more than 50,000 plants, animals and ecological communtities of the U.S and Canada. NatureServe Explorer provides in-depth information on rare and endangered species, but includes common plants and animals too. NatureServe Explorer is a product of NatureServe in collaboration with the Natural Heritage Network.

    ITIS Reports -- ITIS (the Integrated Taxonomic Information System) is a source for authoritative taxonomic information on plants, animals, fungi, and microbes of North America and the world.

    Last updated: November 22, 2009