History
Brook trout are native to eastern Canada and the United States as far south as northern Georgia. The species has been widely introduced into suitable and unsuitable habitat in the West. Dr. Peter Moyle of the University of California-Davis reported that brook trout were introduced into California as early as 1871. By the 1890s, there were being cultured in western states and were widely introduced.
Threat
Introductions of brook trout are often cited as one of the principal causes of decline of the threatened bull trout. Bull trout hybridize with brook trout and the rapid reproduction of the latter species often means that bull trout are mostly or completely eliminated where the two species occur. Although brook trout do not hybridize with redband and cutthroat trout, they compete with the native trout for food and habitat and often result in reduced numbers of the native species.
Management Implications
Brook trout are fall spawners and can survive in a relatively wide range of lake and stream conditions. In many western streams, brook trout grow slowly and reproduce rapidly, resulting in large populations of "stunted" fish. Although extreme, one California stream is known to produce 10-inch fish that are more than 20 years old. Because of impacts to native fishes, most states no longer stock brook trout in stream systems although they remain abundant in many western drainages. Removal efforts are occurring in many streams. For example, in Sun Creek in Oregon's Crater Lake National Park, biologists eliminate brook trout by chemicals and electrofishing in an effort to recover native bull trout.
References
Moyle, P.B. 2002. Inland fishes of California, revised edition. University of California Press, Berkeley.
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