Intra-tropical movements as a beneficial strategy for Palearctic migratory birds

0483903 - ÚBO 2018 RIV GB eng J - Journal Article
Koleček, Jaroslav - Hahn, S. - Emmenegger, T. - Procházka, Petr
Intra-tropical movements as a beneficial strategy for Palearctic migratory birds.
Royal Society Open Science. Roč. 5, č. 171675 (2018), č. článku 171675. ISSN 2054-5703. E-ISSN 2054-5703
R&D Projects: GA ČR GA13-06451S
Institutional support: RVO:68081766
Keywords : geolocator * habitat deterioration * NDVI * passerines * sub-Saharan Africa * vegetation conditions
OECD category: Ornithology
Impact factor: 2.515, year: 2018

Migratory birds often move significantly within their non-breeding range before returning to breed. It remains unresolved under which circumstances individuals relocate, whether movement patterns are consistent between populations and to what degree the individuals benefit from the intra-tropical movement (ITM). We tracked adult great reed warblers Acrocephalus arundinaceus from a central and a southeastern European breeding population, which either stay at a single non-breeding site, or show ITM, i.e. move to a second site. We related ITM to the normalized difference vegetation index (NDVI) describing vegetation conditions and probably reflecting food abundance for these insectivorous birds. Three-quarters of birds showed ITM across the non-breeding range. We found no difference in range values and mean values of NDVI between the single non-breeding sites of stationary birds and the two sites of moving birds. The vegetation conditions were better at the second sites compared to the first sites during the period which moving birds spent at the first sites. Vegetation conditions further deteriorated at the first sites during the period the moving birds resided at their second sites. Our study provides evidence that birds probably benefit from improved conditions after ITM compared to the conditions at the sites from where they departed.
Permanent Link: http://hdl.handle.net/11104/0279085