Risk taking during parental care: a test of the harm-to-offspring hypothesis

Amount of risk taking during parental care is often explainedin relationto the reproductive value of the offspring. The"harm-to-offspringhypothesis" focuses on the relative harma period of no parental carecan do to the offspring. Accordingto this hypothesis, parents should takegreater risks for offspringin poor condition than for offspring in goodcondition. We manipulatedoffspring condition in the pied flycatcher(Ficedula hypoleuca)and tested the harm-to-offspring hypothesis byexposing parentsto a predator model (a sparrowhawk, Accipiternisus). Time elapseduntil a parent first entered the nest-box was usedas a risk-takingmeasure. Parents spent significantly shorter time until firstnestvisit for offspring in poor condition than for offspring ingoodcondition. Hence, the harm-to-offspring hypothesis wassupported.