Estimating the mortality caused by great cormorant predation on fish stocks: pikeperch in the Archipelago Sea, northern Baltic Sea, as an example

摘要: Estimates of the mortality rates caused by cormorants are needed to assess impact on fish stock dynamics and fisheries. In this study, we calculated annual instantaneous great (Phalacrocorax carbo sinensis) young pikeperch (Sander lucioperca), using data from Archipelago Sea, southwestern coast Finland. The vulnerable cormorant predation mainly at ages 2–4. was between 0.04 0.13, estimated effect size recruitment fishery ranged 4% 23%, respectively. average cormorant-induced accounted for 5%–34% total in these age groups. sensitivity analyses proved that other sources largely affect predation. cases with strong fluctuations abundance prey stocks, ignoring density dependence natural mor...