Absence from the nest due to human disturbance induces higher nest predation risk than natural recesses in Common Eiders Somateria mollissima

摘要: Human disturbance of nesting birds may cause reduced breeding success. It is therefore necessary to assess the impact identify steps that minimize negative impacts. We carried out a study success at two adjacent colonies Common Eider Somateria mollissima on islands Grindoya and Hakoya in northern Norway between 2006 2011. Over period, was consistently higher (69–82%) than (35–60%). Between 2009 2011 we used camera monitoring individual nests determinants nest survival predation, focusing particular effect departures from due human disturbance, which differed long-term research project Grindoya. Overall, absence Eiders increased predation risk by factor 6.42 for an increase one additional daily disturbance. In contrast, natural recesses did not losses. Under high levels indicated main failure primarily Hooded Crows Corvus cornix, but also some extent Great Black-backed Gulls Larus marinus. The presence cameras risk. Both researchers sight females conspicuously departing are likely have provided cues these predators. suggest management trials reduce through guarding unoccupied mitigate effects reproductive