Owls on the Adriatic island of Lastovo and the diet of the Tawny Owl Strix aluco (Southern Dalmatia, Croatia)

This paper reviews the owl fauna of the remote Adriatic island of Lastovo and its archipelago, and reports for the first time on the Tawny Owl Strix aluco diet analysis from the Lastovo island. In the field survey on Lastovo and the islet of Mrčara in July 2017, the occurrence of four owl species was confirmed: the Eurasian Scops Otus scops , the Little Athene noctua , the Long-eared Asio otus and the Tawny Owl, while the occurrence of the Eagle Owl Bubo bubo is uncertain according to the literature review. The most frequently recorded owl species was the Eurasian Scops Owl. The successful breeding of the Tawny Owl on Lastovo was confirmed for the first time. Its diet was dominated by mammals, with 97% of prey by number, and 99% by biomass. By far the most common prey was the Long-tailed Field Mouse Apodemus sylvaticus , as well as the Black Rat Rattus rattus in terms of biomass. Birds were of marginal importance as prey of the Tawny Owl, at least in the summer months.