Our ringing of Reed and Sedge Warblers over the past two days produced the first signs that adults of both species are preparing to leave on migration by putting on fat prior to their departure.
Three adult Reed Warblers showed this very well .They normally average around 11.5 grams but these three weighed in at 13.8, 14.2 and 14.6 grams and had significant signs of fat accumulation with fat scores of between 3 and 5. In total we caught 17 adult Reed Warblers but only these three showed any signs of fat accumulation.
We caught smaller numbers of Sedge Warblers but one had a fat score of 3 and a weight of 12.6
Past recoveries of both species have shown how early these birds move with several recoveries of adults along the south coast of England from late July on and even in Northern France as early as August 8th
John
1 comment:
I have caught two control Reed Warblers in the last two days, one with 5 and the other with 4 of fat - birds are definately on the move as you say!
I'll miss most of the migration through Rimrose, but we should start catching British Reed Warblers in Portugal from the second week of August onwards...fingers crossed!
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