Changes occurring over time in commercially exploited fish assemblages in lowland dam reservoirs
2011
Wisniewolski, W. | Borzecka, I. | Buras, P.,Inland Fisheries Institute, Olsztyn (Poland). Dept. of River Fisheries
Changes in the ichthyofauna assemblages of three shallow dam reservoirs (Zegrzynski, Wloclawski, Siemianowka) located in Poland are presented based on long-term records of commercial fish catches. As the reservoirs age the evolution in the sizes of the shares of exploited fish species is depicted by temporal trend lines described with regression functions. The species targeted by commercial fishing are assigned to one of four ecological groups _ predatory, eutrophying cyprinid, rheophilic, and others, depending on the role they play in the reservoir. Catches of cyprinid fishes from the eutrophying group increased in each of the reservoirs studied as the years passed. The share of the other fish groups: predatory, rheophilic, and others, exhibited continually decreasing tendencies as the reservoirs aged. Permanent stocking of lowland reservoirs with predatory fish species is recommended
显示更多 [+] 显示较少 [-]