Thirty years of monitoring Curlew Sandpipers Calidris ferruginea at Münster, Germany, during southward migration

Thirty years of monitoring at the sewage farms of Münster, Germany, confirmed the predominantly juvenile composition of Curlew Sandpiper on southward migrations at inland sites. Fluctuations in numbers of migrating birds could, to a degree, be related to annual measures of breeding success, but there were also deviations from this pattern. Such irregularities are probably the result of juvenile migration across a broad front with relatively unpredictable occurrence at any particular monitoring site.