Saturday, 5 May 2007

Larks rise

Norfolk has a number of nature reserves that are, quite rightly, famous for particular species of bird. The Norfolk Wildlife Trust reserve at Weeting Heath is one of these, hosting several pairs of nesting stone curlews each year. These rather unusual waders are not easy to spot, so the hides at Weeting (together with the helpful wardens and volunteers) provide an ideal opportunity to see these rare birds. Another species that can be seen on the reserve at the moment is the woodlark, and a few weeks ago I was fortunate enough to be able to watch a pair of woodlarks, nesting just in front of the east hide. The nest itself was hidden from view, a depression within a patch of longer vegetation, but I was able to watch what I assumed to be the male bird arrive and softly call his mate off the nest. The male bore a unique sequence of tiny colour rings fitted to each leg, enabling his identity to be established and helping local researchers understand the pattern of movements undertaken by these enigmatic little birds. I duly noted the sequence in my notebook and reported it to the British Trust for Ornithology at Thetford, who operate the national ringing scheme on behalf of the British and Irish governments. Just last week I received information back, informing me that this particular individual had been ringed as a chick on 28th April 2004 at a nest site some 3km north of Weeting. Interestingly, in addition to my record from the 8th April, another birdwatcher had seen the bird on the 3rd, also at Weeting. Colour-ringing is a very useful technique since it allows observers to identify individual birds in the field without having to recapture them.

This particular pair of woodlarks would probably go on to rear another two or three broods this summer and they are part of a healthy and rapidly expanding population. The population first began to expand in the late 1980s, facilitated by an expansion in the amount of restored heathland and young plantation woodland. Thetford Forest has been the focus for much of this expansion and the number of breeding territories within the forest had increased from 48 in 1980 to 446 territories by 1997 (when the last national survey was carried out). There has also been a tremendous increase in the number of woodlarks nesting on the surrounding heathland, thanks primarily to the introduction, in 1988, of the Breckland Environmentally Sensitive Area (ESA) Scheme. It now seems likely that Breckland, together with the Suffolk Sandlings, supports just under half of the national population. Mind you, there is still some way to go before the species re-occupies all of its former range.

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