Some of Clear Lake's earliest human impacts are tied to the introduction of non-native fishes, dating back to the early 1870s. Clear Lake served the late 19th Century as a "testing ground" for fish introductions, often with little regard for native species (Dill and Cordone, 1997). Certain introductions have played a key role in determining the structure of the Clear Lake ecosystem. For example, Clear Lake is a top rate fishery for introduced largemouth bass, bringing in anglers for tournaments and recreation alike. The introduction of western mosquitofish and Mississippi silversides was viewed as biological control agents to combat the Clear Lake gnat, yet also provide forage for larger piscivores. There are currently 21 introduced fishes still present in Clear Lake. For more information on a species click on its common name to visit its California Fish Website species page.
| Common Name | Scientific Name |
| black crappie | Pomoxis nigromaculatus |
| bluegill | Lepomis macrochirus |
| brown bullhead | Ameiurus nebulosus |
| brown trout | Salmo trutta |
| common carp | Cyprinus carpio |
| channel catfish | Ictalurus punctatus |
| fathead minnow | Pimephales promelas |
| Florida black crappie | Pomoxis nigromaculatus |
| Florida largemouth bass | Micropterus salmoides floridanus |
| golden shiner | Notemigonus crysoleucas |
| goldfish | Carassius auratus |
| green sunfish | Lepomis cyanellus |
| lake trout* | Salvelinus namaycush |
| lake whitefish* | Coregonus clupeaformis |
| Mississippi silverside | Menidia audens |
| Mud/Grass pickerel* | Esox americanus vermiculatus |
| northern largemouth bass | Micropterus salmoides |
| pumpkinseed | Lepomis gibbosus |
| redear sunfish | Lepomis microlophus |
| smallmouth bass | Micropterus dolomieu |
| threadfin shad | Dorosoma petenense |
| western mosquitofish | Gambusia affinis |
| white catfish | Ameiurus catus |
| white crappie | Pomoxis annularis |
| yellow perch* | Perca flavescens |
*Unsuccessful introduction or thought to be absent from the lake
Selected References
Dill, W. A., and A. J. Cordone. 1997. History and status of introduced fishes in California, 1871-1996. Fish Bulletin 178:1-437.
Jordan, D. S., and C. H. Gilbert. 1895. List of the fishes inhabiting Clear Lake, California. Pages 139-140 in Bulletin of the United States Fish Commission. Vol. XIV, for 1894. Government Printing Office, Washington, D.C., USA. [select Vol. 15 1895. This is a large file that may be slow to load]
Stone, L. 1876. Report of operations in California in 1873. A. Clear Lake. Pages 377-381 in Part III. Report of the Commissioner for 1873-4 and 1874-5. United States Commission of Fish and Fisheries, Washington, D.C., USA.
Thompson, L. C., G. A. Giusti, K. L. Weber, and R. F. Keiffer. 2013. The native and introduced fishes of Clear Lake: A review of the past to assist with decisions of the future. California Fish and Game 99(1):7-41