Native brook trout

The brook trout is the only native char we have in Frederick County. Brook trout are native to the eastern United States and Canada, extending from Georgia to the Hudson Bay and westward into the Great Lakes states.

Brook trout are also known as speckled trout in Canada, where many of these fish are found in larger lakes and ponds. They are very colorful fish, olive to brownish-back with white, wormlike markings (called vermiculations) across the back. Brookies have whitish sides often with pink to red dots with a bluish halo surrounding them. The lower fins of these fish may have orange markings on them.

Credit: maryland.gov

The male trout develops deep reddish to orange color on their flanks during fall spawning season. Brook trout have a square tail that give them their "squaretail" nickname. They require cold, clear, well-oxygenated water that lies within a narrow pH level.

These fish can live in small streams, rivers, lakes and are even found in Lake Superior. Stream inhabitants usually attain a length of 5 to 7 inches, whereas lake run fish can attain a size of 5 pounds or more. Brook trout found in Lake Superior can grow to a size in excess of 10 pounds.

Brook trout are voracious eaters, become mature quickly and have a relatively short life span, usually three to five years. They have a relatively high reproductive potential, with females laying up to 400 eggs. Where they occur together, brook "speckled" trout and lake trout can hybridize to create a fish called a splake.

Because brook trout are very demanding of site conditions, they are a good indicator of stream vitality. Only the cleanest and healthiest of streams can support viable populations of this fish. There numbers have been declining steadily throughout the East due to urbanization, sedimentation, stream temperature rise, stocking of non-native fish (especially brown trout), acid rain and pollution.

In Frederick County, only a small fraction of our streams continue to support brook trout populations; they are usually at the upper ends of the watershed in small reaches. The Eastern Brook Trout Joint Venture, a comprehensive multi-state study and restoration program for brook trout, was initiated in 2005; it was intended to assess brook trout populations, find healthy, breeding populations, and develop strategies for the protection of remaining viable populations and restoration of brook trout into suitable locations. This ongoing project involves many government and private organizations.

The largest concentration of healthy brook trout waters in the U.S. can be found in Maine, which contains nearly 90 percent of the brook trout waters found in the lower 48 states. Brook trout have been stocked outside their native range in the West and throughout the world. In some areas, these fish have become invasive pests harming native trout populations.

Articles by FCFCDB

Nature Notes for 11/11/2012