Providing longer post-fledging periods increases offspring survival at the expense of future fecundity [dataset]

The cost of reproduction is a key concept in life-history trade-offs. However, our understanding of the reproductive costs is biased towards measures of reproductive effort obtained before offspring independence. During the post-fledging dependence period (PFDP) is well known that parents feed and protect their offspring. However, the effort devoted to this reproductive activity has never been considered under the scheme of the costs of reproduction, and the potential fitness benefits and costs, for offspring and parents respectively, of the duration of PFDP remain barely known. We estimated the duration of the PFDP during 5 years using wild common kestrels (Falco tinnunculus) and studied its association with survival probability and future parental reproductive performance. Our results show that longer PFDPs increased the survival probability of fledglings, probably due to the benefits obtained by parental care. Also, we found that providing longer PFDPs was associated with reduced clutch sizes but not number of fledglings the subsequent breeding season in males. We suggest that increased parental expenditure on offspring during the PFDP may represent a potential cost of reproduction in breeding males.