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| Trapping and ringing near ecological barriers can provide useful information about the
migration strategies of bird species. In this paper we analyzed ringing data of the Garden
Warbler, collected within the period of 1950–2008 at the Ottenby Bird Observatory,
south-eastern Sweden, and describe patterns inmigration phenology,morphometrics and
fuel load.Atotal of 4,351 individuals aged as either adults or juvenileswere ringed during
the period (yearly averages 7.3 adults and 83.1 juveniles) in addition to 1,514 birds of unknown
age. Both age-specific and combined yearly totals did not significantly vary over
the years.Median passage dates were 24 August, 30 August and 2 September for adults,
juveniles and birds of unknown age, respectively.Median passage did not change significantly
over the years.Among adults, larger individuals passed the observatory earlier than
smaller individuals. The average fuel load was estimated at 24.3% of Lean Body Mass
(LBM), and late-migrating individuals had higher fuel deposits than earlymigrants.Maximum
fuel load was estimated at 82.5% of LBM; such an individual may be capable of a
direct flight from Ottenby region to the Mediterranean area. | |
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