Conservation measures for the Caspian Tern Hydroprogne caspia at the largest colony in Sweden

We present conservation actions during 2007–2020 as part of the national Caspian Tern Hydroprogne caspia species action plan at Stenarna in Björn archipelago, Uppland, largest colony Sweden. applied a combination monitoring, research, and management measures conducted within an adaptive approach framework, using both established novel techniques. The implementation led to increased breeding success, from 0 fledglings per pair 2007 1.3 2020. A surveillance video camera installed 2009 aided monitoring efforts also revealed predation by Herring Gull Larus argentatus White-tailed Eagle Haliaeetus albicilla, leading species-specific control strategies. Management island surrounding including hunting invasive American mink Mustela vison, vegetation removal, habitat restoration after severe storm, have been instrumental success project. Implementation projects such this potential improve conditions for continued viability endangered changing world are likely be useful other practitioners.