Saturday 17 July 2010

Moult

The ploughed field is still suspiciously free of vegetation, but is attracting lots of corvids and gulls. Today a mixed flock of over 400 Crows, Rooks and Jackdaws were present, here with a Red Kite quartering the field:
The Gulls were all immatures or loafing subadults, mainly graellsi Lesser Black-backs, but a few Herring and Black-headed Gulls.

Moult was the theme of today, a lot of the adult corvids are in active moult and are replacing flight and tail feathers, a few were in a right state, their wings resembling broken venetian blinds:

This Red Kite demonstrates moult in action and is recognisable due to its distinctive moult pattern: First, a photo taken last week, note this bird is growing a new fourth primary, p4, which on 11th July is well short of the tip of p5, the next innermost feather. Also note the new growing outer tail feather, about 1/3 of the length of the tail:
Six days later p4 has grown and is nearly as long as p5, whilst the outer tail feather is also longer and is now about 1/2 of the length of the tail:

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