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In partially migratory bird species, some individuals of a population migrate while others stay in the breeding area. Although Common Kestrels Falco tinnunculus are defined as partial migrants, their migratory strategies are still not well described. We investigated ringing and re-encounter data of Kestrels marked as nestlings between 1924 and 2011 in Germany. We defined four populations corresponding to the natural regions of Germany. Although both migratory and resident individuals were found independently of sex or age class at the time of recovery, in general, females and juveniles travelled larger distances than males and adults, respectively. We illustrated the initiation of migratory movements in contrast to dispersal by combining distances and directions in two levels (< 100 km and ≥ 100 km), showing that migration is initiated mostly in September/October, while in August movements seem to mostly reflect dispersal. The NAO Index as well as age class, region and re-encounter period (1950-1970,1971-1990 or > 1990 as indicator of responses to climate change) of birds in autumn and winter were integrated into Generalized Linear Models. We found that in autumn and winter a tendency to migrate is primarily shown by juveniles and it was significantly higher in years before 1971 than in recent decades. In addition, a higher NAO Index in summer is linked with decreased proportion of birds re-encountered far (> 100 km) from their natal sites in winter, whereas a higher NAO Index in autumn is linked with increased proportion of high-distance re-encounters (> 100 km).
Knowledge about flyways, breeding and overwintering sites is important for conservation efforts, but little is known about migration patterns and population connectivity of declining European Turtle Doves Streptopelia turtur. EURING ring-recovery data were used to estimate directions and proportional usage of flyways. The timing of migration was compared along these routes and breeding origins of shot individuals were determined. Ring recoveries of Czech, Hungarian, British, German and French birds suggested three main flyways with westerly, central and easterly directions. The proportional usage was estimated by multinomial mark-recovery models. Major parts of French (62%), German (92%) and British (94%) Turtle Doves followed a western flyway. Czech birds used the central route (56%) and 55% of Hungarian birds followed the eastern flyway. Thus, a migratory divide between the Czech Republic and Germany could be suggested. The timing of migration showed a similar latitudinal pattern of migration along all flyways. Birds were at the breeding grounds in June and July and from September to April in their southernmost distribution ranges. Outward migration started in August. Return migration was still evident in May. The majority of reported hunted doves were from the 1960s and 1970s. High hunting numbers were present in September, April and May. France and Spain mainly shot birds from the UK and France. In Italy predominantly Italian birds were shot. Doves shot in Greece mostly came from the Czech Republic. Given the decreasing population numbers, large ringing numbers seem unlikely in the future. Thus, low recovery numbers in recent decades parallel both, the population decrease and a lower ringing activity.
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