The timing of spring migration in trans-Saharan migrants: a comparison between Ottenby, Sweden and Capri, Italy
Keywords:phenology, tropical migrants, long-distance migration, migration speed, Passeriformes, climate change
Some migratory birds have advanced their spring arrival to Northern Europe, possibly by increasing the speed of migration through Europe in response to increased temperature en route. In this paper we compare the phenology of spring arrival of seven trans-Saharan migrants along their migration route and test for patterns indicating that migration speed varied over the season using long-term data collected on the Italian island of Capri and at Ottenby Bird Observatory, Sweden. There was a linear relationship between median arrival dates on Capri and at Ottenby. The slope was not significantly different from one. On average, the seven species arrived 15 days later at Ottenby compared to Capri. There was a (non-signiﬁcant) negative relationship between the species-speciﬁc arrival dates at Capri and the differences in median arrival dates between Capri and Ottenby, possibly indicating a tendency towards faster migration through Europe later in the season. To what extent different species are able to speed up their migration to beneﬁt from the advancement of spring events is unknown.
How to Cite
The copyright of each contribution belongs to the author(s), but all contributions are published under a Creative Commons license, so that anyone is free to share and reuse the contribution as long as the copyright holder is attributed.