Advanced spring arrival of avian migrants on Tipperne, western Denmark, during 1929-2008

摘要

Det seneste tiårs studier af traekfuglefænologi har bidraget til forståelsen af klimaforandringers påvirkning af fugletrækket, og mange studier har påvist tilpasning i form af trækfugles tidligere ankomst til yngleområderne. De flesternfænologistudier har imidlertid fokuseret på få arter - oftest spurvefugle - over perioder på 30-40 år. Yderligere indsigt i trækfugles tilpasning til klimaforandringer må nødvendigvis baseres på flere og taksonomisk mere forskellige arter, studeret over længere perioder på samme lokalitet.rnI nærværende undersøgelse har vi analyseret ændringer i forårsankomsterne hos 43 fennoskandinaviske ynglefugle tilhørende forskellige taksonomiske grupper (Tabel 1) på baggrund af 80 års standardiserede observationer på Tipperne i Vestjylland.%During the last decade, phenological studies have increased our knowledge on climate-induced changes in timing of avian migration. Much work has been done using long-term, standardised data. However, the vast majority of previous studies have focused on data covering 3-4 decades and limited to specifk species groups. In the present study, we analysed temporal patterns in spring arrival of 43 taxonomically diverse Fennoscandian bird species based on a long-term data series covering 80 years (1929-2008) from the Tipperne reserve in westernmost Denmark. Furthermore, we assessed how spring arrival was related to variation in climate. Overall, spring arrival advanced by a mean of 0.26 days/ year, corresponding to a three week advance during the 80 year study period. While short-distance migrants advanced on average 0.38 days/year, long-distance migrants only advanced 0.17 days/year.These patterns in first arrival dates were confirmed by patterns seen in arrival of the first five or ten individuals. Overall, changes in environmental conditions (temperature, precipitation and the North Atlantic Oscillation) during winter and spring explained much of the changes in phenology. Interspecific variation in response to climate is partly explained by different migration strategies.