Just an evolutionary quirk I would think. Both the Crab Plover (finally
ticked this one this year) and the Pied Avocet are white and black - both
have grey legs.
See http://www.worldbirder.com/photonew/xpages/photo.asp?PhotoID=1200
Also, no black and white Raptor, that I am aware of has red legs.
Tim Murphy
-----Original Message-----
From: Greg
Sent: Saturday, 29 July 2006 6:27 PM
To: Tim Murphy;
Subject: Pink/Red colouration of legs and bill
ofPiedOystercatchers
While the 'brains trust' is thinking about red-legged Oystercatchers and
Black-winged Stilts (although the stilt's legs are really pink) give some
thought to the Black-necked Stork, which also has bright red legs.
As far as the suggestion that the brightness of the legs could indicate the
health of the bird and therefore its suitability as a mate the following
should be noted:
the brightness or redness of the legs changes noticably with the angle of
light:
mating and contact displays are carried out in a manner that the legs would
be mostly obscured from view;
during hot weather storks sometimes chalk their legs by defaecating over
them making them quite pale.
It is interesting that oystercatchers are black or black and white and
Black-necked Storks and Black-winged Stilts are Black and White. The White
Stork, which is also black and white, has both a black billed and a
red-billed race. Some other stork species have red or reddish legs.
Is there a pattern here?
Regards
Greg Clancy
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