Using Large-Scale Data from Ringed Birds for the Investigation of Effects of Climate Change on Migrating Birds: Pitfalls and Prospects

Ringing recovery datasets at ringing centres cover large areas and long time-spans, and, therefore, they are interesting for investigating long-term changes in bird migration. This chapter analyses selected data from three German ringing centres “Helgoland,” “Hiddensee,” and “Radolfzell” to explore the value of German recovery data for investigating temporal changes in bird migration behavior. Although heterogeneity of the data in terms of ringing activity, recapture, re-sighting effort, recovery probabilities, or reporting probabilities of recoveries on a temporal, and spatial scale are major problems for these types of long-term analyses, the data offer promising possibilities. The possibilities of ringing and recovery databases at ringing centres cover larger areas and longer time-spans than most single studies; in contrast to pure observations and bird counts, individuals with deviant behavior (like wintering at northern latitudes by migrants) can be assigned to distinct populations; and the datasets are rapidly available in standardized, electronic format. German datasets are used to investigate prospects and pitfalls in using data from bird ringing databases for analyzing the effects of climate change on migrating birds.