Thursday, 15 July 2010

Terning the tide

Gadwall brood and Draper scrape with Garganey

Rye Meads is a highly productive site for breeding waterbirds, ducklings seemed to be everywhere during my visit today, with a minimum of 15 broods of Tufted Duck, 7 of Pochard and 11 of Gadwall scattered around the various lagoons. The Draper scrape also produced a juvenile Garganey, a Shelduck, 2 Green Sandpipers and a Common Sandpiper.

However, it was the Common Tern colony that was the main reason for the visit. They have been squeezed off their rafts by Black-headed Gulls in the last 2 or 3 years. This year the totals appear to be 19 pairs of terns to 21 pairs of gulls. The gulls have been very productive, the terns have not, only six tern chicks were visible today. How to provide for the terns in the face of the advancing gulls is a management dilemma at the moment, with a variety of ideas to be trialled over the next year or so. Elsewhere in the Lee Valley, terns are doing well, with productive colonies at Amwell and Cheshunt (although only 2 pairs of BHGs are nesting at the latter site). Competition between terns and gulls is commonplace around the coastal colonies, with terns having minimal productivity or being completely ousted at some sites. However, inland on tern rafts, this is a new and growing trend. These tern colonies have traditionally been very productive. Time will tell if they continue to be so.

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