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| Long-term ringing data are useful for understanding population trends and migration strategies adopted by
migratory bird species during migration. To investigate the patterns in demography, phenology of migration
and stopover behaviour in Wood Sandpipers Tringa glareola trapped on autumn migration at Ottenby,
southeast Sweden, in 1947 - 2011, we analysed 65 years of autumn ringing data to describe agespecific
trends in annual trappings, morphometrics and phenology, as well as fuel deposition rates and
stopover duration from recapture data. We also analysed the migratory direction of the species from
recovery data. Over the years, trapping of both adults and juveniles has declined significantly. Median
trapping dates were 10 July for adults and 6 August for juveniles. Average migration speed of juvenile
birds was 58.1 km d-1. Adults stayed on average 3.5 days and juveniles 5.2 days, with average fuel
deposition rates of 2.5 and 0.7 g day-1 respectively. Juvenile birds probably vary their strategy according
to time of season and prevailing conditions. Both adults and juveniles followed the Mediterranean
Flyway, but juveniles displayed significantly more southerly and significantly more scattered migratory
directions. | |
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