Sunday, 12 February 2012

Black-headed Gull - (Chroicocephalus ridibundus) - summer-plumaged

I saw my first full summer-plumaged Black-headed Gull of the year over Seaford, East Sussex today. I have seen quite a few in the past month or so beginning to get their chocolatey hood but this was the first to have fully acquired plumes.

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(Black-headed Gull- © John Bridges)
Black-headed Gulls with a partially developed hood such as this are quite common in winter (e.g out of 200 or so Black-headed Gulls at Arlington Reservoir, East Sussex yesterday I saw at least 10 looking similar to this.

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(Black-headed Gull-  © John Bridges)
But birds with a full chocolatey hood are the best of them all! That ridibundus I saw today was my first full-hooded bird since they began moulting at the end of the summer. Moult into winter plumage typically takes place from July-October, with the head feathers among the first be replaced. The return moult typically starts in late January/Early February, but in mild winters (and until a few weeks ago this was a mild winter for most) head moult can begin in late December. The earliest fully developed hoods, according to Malling and Olsen, appear about mid-January, but studies in S Scandinavia have shown only 1-5% of adults have a fully developed hood by the end of February, meaning my bird is still an anomaly this early in the year. 

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