A recent recovery of a Sedge Warbler on 28 August in Seine-Maritime France just 13 days after ringing in our area inspired me to look through our files for similar quick movements.
We have 4 reports of Sedge Warblers ringed in the Tay reed beds in eastern Scotland in mid to late August and caught in our area all 4 just 7 days after ringing. So many of the Sedge Warblers we catch are obviously of Scottish origin and have already started their migration.
Perhaps the most interesting report was a young bird ringed at Leighton Moss on 13/08/04 at 10.00 and caught next day at 05.50 at Brandon Marsh Warwickshire. Sedge Warblers are night migrants so this bird had travelled 220 km in one night which at that time of year means a maximum ca. 6 hours of flying time with a minimum speed of ca 35 km per hour. When originally caught it weighed 12.7 grams and when retrapped it had lost exactly a gram!
Of course we don't know if a bird starts migrating the next night after ringing or if it was caught as soon as it arrives at the site it is reported from. So the details given below should be considered with this in mind.
Birds have traveled the c.400 km to reach the English south coast in 4 days(2), 5 days (3) 6 days (3) 7 Days (2) 9 days (2) and 10 days (2).
Going further afield birds have reached Belgium in 10 days, France in 11, 14(2), 16days and 23 days. These birds travelled between 700 and 1323 km.
All this information has come from other ringers catching and releasing our birds. For our part we have ringed almost 11,000 Sedge Warblers in our area.
John Wilson
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