Sunday, 13 July 2014

A warblerfest

July has picked up where June left off with many species successfully raising young. Warblers have shown a significant rise with sylvia warblers heading towards record numbers compared to previous years. Garden Warblers, Blackcaps and Whitethroats just seem to be everywhere with good numbers been trapped on each visit. So far we have been out five times this month and processed 738 birds including 459 new birds ringed. Ist - 89 birds processed, 3rd - 88, 6th - 199, 7th - 137, 9th - 64, 12th - 161. Over 200 new Tree Sparrows have been ringed so far this year, 60 of those have been ringed this month, with lots of juveniles being trapped at the feeding station. Reed Buntings are also having a successful year with 42 juveniles ringed this month and bringing the annual total to 83. So the breeding season is now in full swing and there are still around 6 weeks still to go. Once the adults finish breeding they will go through a full body and wing moult. Warblers such as Blackcap, Whitethroat, Lesser Whitethroat, Willow Warbler and Chiffchaff all moult in this country before their migration. However, Reed Warblers and Sedge Warblers carry out their moult on arrival of their wintering grounds in West Africa. On the other hand Garden Warblers are a bit of an enigma when it comes to moult. Some adults can show signs of wing feather renewal in the UK but others will moult in their winter quarters. At Stanford we don't see many Garden Warblers in wing-moult but on the 6th we caught this adult that clearly shows a suspended moult strategy with all of the secondaries renewed and the inner two primaries have both been dropped.

Adult Garden Warbler in suspended wing-moult - July 6th

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