Determination of Winter Habitat of Large Brown Trout in Southeast Minnesota Streams Using Radiotelemetry. Study 656.

摘要

Availability of suitable winter habitat can limit abundance of large brown trout Salmo trutta in streams, making it vital to determine winter habitat requirements when managing to increase abundance of these fish. We used radiotelemetry to identify winter habitat use by large (332-562 mm total length) brown trout in seven southeast Minnesota streams. We compared macro- and micro-habitat use to availability and determined that these brown trout avoided and selected habitat features. Emigration after spawning and overwinter mortality reduced abundance of large trout in the study streams by up to 40%. After spawning, large brown trout selected a pool and moved little during the winter. They generally avoided the smallest pools available, and pools with little or no water deeper than 60 or 90 cm, woody debris, and total cover; and selected the largest pools available with abundant deeper water, overhead bank cover, cover from woody debris, and total cover.