Year-round spatiotemporal distribution of the enigmatic Semi-collared Flycatcher Ficedula semitorquata

We examined migration routes and non-breeding sites of a poorly studied long-distance migrant, the Semi-collared Flycatcher Ficedula semitorquata, by tracking adult birds with geolocators from an eastern European breeding population across two subsequent years. All 11 birds migrated in a clockwise loop fashion where autumn migration routes lay east from the spring migration routes. Non-breeding sites were located in Eastern-Central Africa, i.e. Uganda, Tanzania, Burundi, Rwanda, and east DR Congo, where birds spent on average 128 days. Non-breeding sites of two birds were located outside of the currently estimated species’ non-breeding range.