Barboutis C, Larsson L, Steinholtz Å, Fransson T (2015) From Mediterranean to Scandinavia – timing and body mass condition in four long distance migrants. Ornis Svecica 25:51–58
A new ABO paper on the phenology of spring migration of Icterine Warbler, Wood Warbler, Spotted Flycatcher and Collared Flycatcher has just been publish from Ornis Svecica. The study deals with phenology and body mass data collected from two bird Observatories, one situated in South Europe, ABO, and one in Scandinavia, Sundre Bird Observatory (Gotland, Sweden) All the study species migrate due north which means that some proportion of birds that pass through Greece are heading to Scandinavia. The differences in median dates between Greece and Sweden were 3–4 weeks and the passages in Sweden were generally more condensed in time. The average overall speed estimates were very similar and varied between 129 and 137 km/d. In most of the species higher speed estimates were associated with years when birds arrived late in Greece. After crossing continental Europe birds arrive at the Swedish study site with significantly higher body masses compared to when they arrive in Greece and this might indicate a preparation for arriving at breeding grounds with some overload. This study is an excellent example on who data from Bird Observatories around the globe can contribute knowledge of the natural history of birds.
A copy of the study can be find here