View in other NatureServe Network Field Guides
NatureServe
Montana
Utah
Wyoming
Idaho
Wisconsin
British Columbia
South Carolina
Yukon
California
New York
Rock Bass - Ambloplites rupestris
General Description
The rock bass is a stout little sunfish with a red eye. They were introduced in Wyoming and found their way downstream in the Tongue River drainage of southeastern Montana, which is presently their only known locale. Montana is apparently too cold for these 6-8 inch sunfish to thrive, and they are of little importance in this state although they are popular panfish elsewhere. All of the sunfishes are important forage fish for northern pike, walleye, and bass.
Diagnostic Characteristics
Body robust.
Species Range
Montana Range
Range Descriptions
Non-native
Observations in Montana Natural Heritage Program Database
Number of Observations: 52
(Click on the following maps and charts to see full sized version)
Map Help and Descriptions
Relative Density
Recency
(Observations spanning multiple months or years are excluded from time charts)
Migration
Studies on Tongue River showed migration movements into Otter Creek late May - early June. Probably related to spawning.
Habitat
Pools of rocky-bottomed streams; rocky shallow areas of lakes. Seeks moderately warm water. In Montana, found only in Tongue River Drainage.
Food Habits
Eats many kinds of aquatic insects, crustaceans, mollusks, and small fishes.
Ecology
Do not commonly exceed half a pound in north waters. Montana waters are marginal for this species.
Reproductive Characteristics
Sexually mature at 2 - 3 years. Spawns May - June in slow current over gravel bed. Eggs and fry defended vigorously.
Stewardship Responsibility
References
- Additional ReferencesLegend:
View Online Publication
Do you know of a citation we're missing?
Holton, G.D. 1981. Identification of Montana's most common game and sport fishes. Montana Outdoors May/June reprint. 8 p.- Joslin, Gayle, and Heidi B. Youmans. 1999. Effects of recreation on Rocky Mountain wildlife: a review for Montana. [Montana]: Montana Chapter of the Wildlife Society.
- Penkal, R.F. 1977. Black bass populations of the Tongue River Reservoir, Montana. M.Sc. Thesis. Bozeman, MT: Montana State University. 111 p.
- USDI Bureau of Land Management. No date. Fishes of the Miles city, Montana BLM District. Miles City, MT: Miles City BLM District pamphlet. 12 p.
- Web Search Engines for Articles on "Rock Bass"
- Additional Sources of Information Related to "Fish"
