Satellite tracking of pre-breeding migration of Song Thrushes Turdus philomelos wintering in Italy

The miniaturization of individual tracking devices has greatly enhanced our ability to remotely track the migratory movements of even relatively small species (50-100 g). One such species is the Song Thrush Turdus philomelos, a short-distance, intra-palearctic migratory passerine with a broad wintering range spanning all Mediterranean countries. In many of these regions, the species faces intense hunting pressure. Identifying its migration routes and phenology is therefore essential for informing management initiatives targeting this game species. Between 2021 and 2024, a total of 48 Song Thrushes were captured using mist nests between early December and January across three Italian regions: Sardinia, Marche and Puglia. They were fitted with the smallest available Argos PTT tags (2 g). We documented 31 pre-breeding migrations. Among 26 of these migrations with sufficient data, the mean onset of pre-breeding migration was 19 March ± 16.88 (s.d.), with the earliest movement northeastward recorded on 31 January. Due to widespread tag failures, we obtained complete migration tracks only for six individuals. Three of these migrated to putative breeding sites in Russia east of the Urals, two to sites west of the Urals, and one to Romania. Our findings suggest that Song Thrushes wintering in central-southern Italy originate from a wide geographical range, spanning from eastern Europe to East Siberia, highlighting the importance of Mediterranean countries for different breeding populations.