Piscivorous birds as top predators and fishery competitors in the lagoon ecosystem

摘要: Piscivorous birds have received much attention with respect to competition fisheries for resources. The majority of studies been focused on cormorants Phalacrocoracidae, while predation by other piscivorous bird species has often overlooked. This study was designed supplement sociological research (Bell, 2004), which revealed that the fishermen community at Lithuanian section Curonian Lagoon considers great Phalacrocorax carbo, but not fish-eating birds, be significant competitors fish In this paper, we estimate consumption and abundant attempt interpret level in relation resources commercial fishery landings. We four consumed nearly 700 tonnes during breeding season 2001 winter 2001/2002, corresponds ~9% total our area. Bird equalled two-thirds amount landed fishermen. However, argue direct between humans is low, because there a size segregation exploited stock segments dominate diet birds. Fish monitoring landings indicated no apparent changes composition, could attributed recent increase Great largest biomass compared species. intake grey herons Ardea cinerea, great-crested grebes Podiceps cristatus, goosanders Mergus merganser combined, cormorants. Our results do support common public perception cormorant greatly exceeds detrimental fisheries.