Migration and morphometrics of the Broad-billed sandpiper Limicola falcinellus at Ottenby, southern Sweden, 1950-2000
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The Broad-billed Sandpiper Limicola f. falcinellus is a little studied European wader species with unfavourable conservation status. We describe the migration of the Broad-billed Sandpiper at Ottenby, southeast Sweden, from 1950-2000 using data from ringing activities and field observations. Numbers of ringed and observed Broad-billed Sandpipers varied considerably between years. There was no trend in numbers trapped over the study period, but a positive trend in numbers observed (probably explained by improved identification skills and observation possibilities). The populations passing Ottenby during autumn migration have probably been relatively constant in size during the last 50 years. The species was only rarely seen during spring migration (median 29 May). As shown by autumn ringing data, adult birds pass mainly in July (median date 21 July) and juveniles mainly in August (median date 17 August). Adult birds had on average somewhat longer wings and longer total-head than juvenile birds, but there were no significant differences in body mass between age groups. Broad-billed Sandpipers carried an average fuel load proportional to 25% of lean body mass, which is relatively low for migrating waders, but some individuals may have had fuel stores of up to 50-70%. In recaptured birds, the highest recorded mass gain rate was 7.1% of lean body mass per day, which is close to the maximum predicted for a species of this size. Broad-billed Sandpipers seem to prefer migrating with relatively small fuel stores, making use of several stopover sites along the migration route.