Monday, 5 May 2014

More BTG.

Virtually all wintering Black-tailed Godwits in Britain are of the race islandica, the population size of which is estimated to be 47,000, having increased over the past 100 years and showing no sign of levelling out.

There is a strong suggestion that individuals don't use fixed wintering sites or migration routes, born out by multiple sightings of birds ringed on autumn passage on the Wash and recovered at various seasons in Lancashire, together with further multiple sightings of colour ringed birds in Britain, Ireland, France, and Holland.  

Black-tailed Godwit. Martin Jump.

The Black-tailed Godwit has featured highly in my birding this spring. An amazing c.700 were on Conder Pool 17 April, and these and another 200 birds made the total up to at least 900 later the same day on the Lune Estuary at Glasson Dock, good counts were also made around the same period at Cockersands.

On several occasions recently Conder Pool has offered the best of opportunities to get close to the Black-tailed Godwits from the viewing screen and easily read any ringed birds, and I've had the pleasure of finding five such birds with another find forwarded to me.

With the reliable and co-operative Böðvar in Iceland I have been forwarded some excellent histories of ringed birds, including two visiting Porto Alto, Lisboa, W.Portugal, and one visiting six different sites in France. 

Black-tailed Godwit. Martin Jump.

Ringed as chick 13.07.12 Bragholt, Road 811, Hjalteyri, Eyjafjordur, N Iceland.

GW-RY=Green over White ring left leg. Red ring over Yellow flag right leg. 

GW-RYflag 07.11.12 Warren Farm, Talacre, Flintshire, NE Wales.
GW-RYflag 29.03.13 Ladys Island Lake, Co. Wexford, S Ireland.
GW-RYflag 08.07.13 Marshside RSPB Reserve, Merseyside, NW England.
GW-RYflag 28.04.14 Glasson Dock, Lune Estuary, Lanc's, England. P Woodruff.

This bird could be my last one to be found ringed on the Lune Estuary this spring, my best ever for such sightings both in number and ringed birds. 

The two images above are of the Black-tailed Godwits at Newton Marsh, the bottom one of which illustrates a bird of the continental sub-species limosa which has bred in small numbers at Newton Marsh in the past, but egg collectors took clutches and the site was forced to be wardened against this and other forms of predation. Thanks to Martin Jump for the images. 

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