jueves, 10 de junio de 2010

Bar-tailed Godwit (Limosa lapponica) Early June

This solitary example of a Bar-tailed Godwit (Limosa lapponica) was discovered in a freshwater basin in Las Martelas on June 6th, perhaps a somewhat atypical location for a species described in most identification guides as being more inclined towards saltwater habitats.

On the Canaries considered a "regular passage migrant and winter visitor, recorded from all main islands" (Tony Clarke, "Birds of the Atlantic Islands", Helm), this was nevertheless my first sighting on La Palma.

The present images allow a number of key identification points to be appreciated: the shorter legs in comparison to the Black-tailed Godwit (Limosa limosa), the pale supercilium extending to behind the eye...
...the obviously barred tail (!) and white rump...
...and the very slightly upturned bill, the length of which suggests a female.

The baueri, or eastern race of the Bar-tailed Godwit, holds the record for the longest-known non-stop migration flight of any bird. Satellite tagging showed that in 2007 one bird flew from North Island, New Zealand, over the Western Pacific to the Yellow Sea, a distance of at least 10,000 km.

Birds of the "lapponica group" generally breed on low-lying tundra discontinuously from northern Scandinavia through Russia to Alaska, and use coastal and estuarine environments when not breeding: lapponica largely in Britain, Ireland and Denmark; tymyrensis south down the Atlantic seabord to west and southern Africa ("Shorebirds of the Northern Hemisphere", Richard Chandler).

Reaching La Palma has not necessarily entailed an extended ocean crossing for the present bird, but it has meant a journey south covering approximately 40 degrees of latitude - no mean achievement!

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