BOTH C, BIL W & OUWEHAND J (2019) A comparison of site fidelity and survival of Pied Flycatchers Ficedula hypoleuca in the wintering and breeding areas. LIMOSA 92 (3): 184-191.

Little is known about the ecology of Palearctic migrant passerines at their African wintering grounds, despite that they spend most of their annual cycle in Africa. Here we report about our ongoing work on Pied Flycatchers, that we study both at their wintering grounds in Comoé National Park (Ivory Coast) and at their breeding grounds in Drenthe (the Netherlands). We show that local return rates of ringed adults with geolocator loggers is quite similar for male flycatchers to Comoé and Drenthe, whereas for females return rates seem slightly higher to Comoé than to Drenthe (Tab. 1). In both years in which we caught Pied Flycatchers in Comoé, the sex ratio was male biased (total 46 males, 26 females). Also our earlier field observations in Ghana showed an overall male-bias, which changed during the late-winter and spring season (Fig. 1). This male bias is consistent with earlier results from the breeding areas, where males normally recruit into the breeding population at a later age than females. We do not yet know where and when in the annual cycle this sex-ratio bias arises. In box 1 we describe how simultaneous estimates of annual survival from both breeding and wintering areas allow us to better estimate whether and how survival varies throughout annual cycle periods, using a hypothetical dataset.

[pdf only for members] [dutch summary]