Survival rates of adult European Nightjars Caprimulgus europaeus breeding in northwestern Italy

Abstract

Survival rates of breeding adult European Nightjars were estimated from capture–mark–recapture data, collected from 1997 to 2009 at a ringing station in northwestern Italy. Birds were trapped without the use of playback. A sample of 109 European Nightjars, obtained with mist-nets operated each year during the May to July breeding period, provided 158 capture events. Survival and recapture probabilities were estimated with program MARK, and the effects of some climatic factors (local and Sahelian rainfall and NAO) were tested. Overall, variation in survival rates was not clearly associated with any of the climate factors considered, but variation in these over the period was relatively low and the power to examine inter-annual variation in survival was also low. Finally, the time- and sex-independent model gave an annual survival rate of 0.70 ± 0.05 (se), with sex-dependent recapture probabilities which were lower for females (0.19 ± 0.05) than for males (0.35 ± 0.07).