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 specific 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.