Wednesday, 27 May 2015

Wednesday 27th May 2015

Weather;  Overcast with rain in the afternoon. Winds light F2 W- NW.

Around 5,000 Dunlin were on the sands today between Dove point and the western groyne along with around 300 Ringed Plover and 50 Sanderling. The Dunlin passing through the Wirral to all points north through the spring comprise of several different races. The taxonomic position of these races is at present in a state of massive flux with recent studies indicating the racial composition is not what it was previously thought to be. It is far too complex an issue to be addressed here but to simplify matters birds from the north-west of the range starting from Greenland are smaller, duller, and with smaller bills than those to the east. The further east the larger, more rufous above, and longer billed they get, and the darker and better defined their belly patch becomes.
A very large billed and bulky Dunlin. Note the very rufous mantle and well defined belly shield. Birds of this build and colour are now thought to originate from north east Siberia. Their racial identity is under debate and such individuals are currently known as 'centralis types'   (photo JET)

Mark and Jane Turner have been studying the Wirral Dunlins extensively and have observed some interesting individuals amongst today's migrants.(photos attached)

A very small, grey and short billed Dunlin with ill defined belly patch probably from the Greenland population. Race currently known as arctica.  (photo MGT)
A large, long billed Dunlin probably from the East Siberian population. (bird furthest to the left) Note the broad Sanderling-type wing bar on this bird compared to the others, another feature of this population.  (photo MGT)
A massive-billed, bulky and rufous Dunlin probably of the east Siberian population. Note also the greater size difference as compared to the upper bird, which is from a population from much further west. The upper bird would once have been thought to be of the northern European schinzii race or possibly a poorly marked alpina.  The nature and extent of these races, however, is currently under debate.  (photo JET) 
Migrants today in the Leasowe area included a single late Tree Pipit flying west. 2 Sand Martins also flew west this morning and a single Wheatear was in the paddocks. There was also a movement of over 300 House Martins and 50 Swifts just ahead of this afternoon's rain front. A single Chiffchaff was seen to fly off  high to the east from coastal bushes this morning, obviously still on passage. It is a mystery where these regularly recorded late moving Chiffchaffs are en route to. (Many thanks to Mark and Jane Turner for their interesting input into today's blog)     
Observers MGT, JET, EW       

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