Numbers of adults caught start to drop in late July and early August and most have left before the end of August. We have 6 controls of adult Reed warblers on the south coast in the second half of July, 11 in August and 3 in the first few days of September. By contrast juveniles don't occur there until the middle of August and reach a peak in the last days of August and early September and continue into September. Almost all the juvs caught today were in post juvenile body moult and had normal weights.
The other amazing thing about todays catch was the complete absence of Sedge warblers on the same date last year at this site we caught 8.