The feeding behaviour of large perch Perca fluviatilis (L.) in relation to food availability: a comparative study
详细信息    查看全文
文摘
The aim of the present study was to analyse and compare the feeding behaviour of large perch (>25 cm total length) in two lakes of different state and corresponding differences in food availability. Investigations were conducted in the Bautzen Reservoir, Germany, (biomanipulated, macrophyte cover <1%) and in Lake Ring, Denmark (non-biomanipulated, macrophyte cover ca. 20%). Fish were sampled regularly using trawl nets and gill nets. We focused our study on seasonal diet patterns. Further, we investigated size-related feeding and predation on both the juvenile fish and invertebrate communities. The availability of Chironominae was high in both lakes (e.g. ca. 1500 ind. m−2 in Lake Ring), but age-0 fish abundance was most probably higher in Bautzen Reservoir (6.4 individuals m−3 in the beginning of June 1998). Invertebrates and age-0 fish were the main food components of large perch of both populations. Mean lengths of prey fish were consistently smaller than those in situ. Large perch in Bautzen Reservoir started earlier to feed on age-0 fish, which was not related to prey fish sizes. Predation on the age-0 fish community was distinctly higher in Bautzen Reservoir than in Lake Ring. Generally, invertebrates represented the most important food of large perch in Lake Ring, whereas the by far dominant food resource of large perch in Bautzen Reservoir was the age-0 fish stock. In conclusion, it can be stated that the prey fish availability was an important factor in determining the feeding behaviour of large perch.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700