Juvenile brown trout response to fine woody debris in experimental stream channels
(English)Manuscript (preprint) (Other academic)
Changes in riparian vegetation due to forest harvesting may affect the input of fine woody debris, an important structural element, to streams. Woody debris has been shown to benefit trout populations. In-stream fine woody debris (FWD) has not been studied as extensively as large woody debris, but is probably important to smaller-sized trout. In a laboratory stream experiment we tested young-of-the-year wild brown trout, Salmo trutta, responses to three densities of fine woody debris (FWD). The trout were tested as singletons and four together. Swimming activity increased with increasing fish density and decreasing FWD density. Foraging decreased and time spent in FWD increased with increasing FWD density. Aggressiveness was lowest in intermediate FWD density. Our study shows that FWD impact on trout is related to fish rank, fish density and FWD density, and that juvenile trout response to fine WD is different from the response to large WD reported by others.
fine woody debris, brown trout, juvenile, streams
Research subject Biology
IdentifiersURN: urn:nbn:se:kau:diva-31671OAI: oai:DiVA.org:kau-31671DiVA: diva2:703935