First-year and adult survival of the endangered Lesser Kestrel Falco naumanni in southern France

Abstract

Capsule Local first-year survival is higher in La Crau than in Spain with a high proportion of first-year birds returning to their natal area. Aims To understand life history parameters that may be responsible for a population growth since the 1990s. Methods Between 1994 and 1998, 342 birds were ringed as fledglings. From capture–recapture data, annual local survival and the proportion of first-year birds returning to their natal area were computed. Results The annual survival probabilities of adult and first-year birds were constant during the study period (0.67 and 0.57, respectively). A high proportion (0.72) of birds ringed as fledglings returned to their natal area after one year. Of these, an estimated 53% bred in that first year. Local first-year survival is higher in La Crau than other areas in Spain. Conclusion The high local survival rate, the product of survival and philopatry, might be responsible for the positive trend of the population. A peculiar aspect of the La Crau population is that ground nests have been increasingly common since the 1990s despite a higher risk of breeding failure.