Abstract

Anthropogenic barriers that may interfere or prevent fish migration are commonly found in streams throughout the distribution of salmonids. Construction of fish passages in streams is a common solution to this problem. However, the goal with fish passages is often, at least in Scandinavia, to allow Atlantic salmon (Salmo salar L.) and migratory brown trout (S. trutta L.) to get access to spawning areas above these barriers. Hence, the fish passages may often only be open during the spawning migration of salmonids (late summer to autumn). We present data, on wild brown trout migration, from two trapping systems in two Scandinavian streams showing that intra- and interstream migrations are common throughout the summer and autumn. Moreover, differences in size were found between trap-caught trout and electrofished trout where trapped trout were generally larger than electrofished trout. We suggest that the current regime with fish passages only open parts of the year can have negative effects on populations by depriving trout from the possibility to perform migrations throughout the year

Keywords

brown trout; habitat shift; migration; movements; Salmo trutta; trap

Published in

Ecology of Freshwater Fish
2004, Volume: 13, number: 3, pages: 161-167
Publisher: BLACKWELL MUNKSGAARD

SLU Authors

• Nordwall, Fredrik

  • Department of Aquaculture, Swedish University of Agricultural Sciences
    

• Eriksson, Torleif

  • Department of Aquaculture, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Environmental Sciences related to Agriculture and Land-use
Fish and Aquacultural Science


Publication identifier

DOI: https://doi.org/10.1111/j.1600-0633.2004.00058.x

Permanent link to this page (URI)

https://res.slu.se/id/publ/4594