Insights into the migration of the European Roller from ring recoveries

摘要: Despite recent advances in avian tracking technology, archival devices still present several limitations. Traditional ring recoveries provide a complementary method for studying migratory movements, particularly cohorts of birds with low return rate to the breeding site. Here we first international analysis recovery data European Roller Coracias garrulus, long-distance migrant conservation concern. Our comprise 58 records Rollers ringed during season and recovered non-breeding season. Most come from Eastern Europe, half are juveniles over three quarters dead birds. Thus, migration Rollers—juveniles unsuccessful migrants—for which no information currently exists, complementing studies. Qualitatively, our results consistent direct studies, illustrating broad-front across Mediterranean Basin autumn use Arabian Peninsula by eastern populations spring. Autumn movements were, on average, more southerly direction than adults, were easterly. Juvenile also appeared be variable though this difference was not statistically significant. This is following naive vector-based orientation program, perhaps explains ‘moderate’ connectivity previously described Roller. In (qualitative) mortality, highlight high prevalence shooting. The age ratio juvenile-biased but adult-biased Although significant, points towards higher mortality adults. study demonstrates complementarity tracking, providing an insight into juvenile mortality.