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First summer Caspian Gull on Felixstowe Docks, Suffolk
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proldfield
- Posts:9
- Joined:Sat Dec 05, 2009 11:59 am
This bird is showing what I believe to be a third generation scapular. Bill colour is not typical either.
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marsmuusse
- Posts:666
- Joined:Sun Sep 27, 2009 12:43 pm
Re: First summer Caspian Gull on Felixstowe Docks, Suffolk
Hi,
The white based scapulars with brown anchor patterns are worn 2nd gen feathers. But there are also a few scapulars with grey base and ill defined patterns, the fringes in better condition. For these feathers it is important to define the exact location.
a. The longest rear scapulars are grey based and look relatively fresh. They were replaced somewhere last in line, and this is exactly what you would expect when an ordinary sequence is followed in the scapular moult process. These are last replaced 2nd gen feathers.
b. But there are also a few grey based upper scapulars, at a location corresponding with the 'first moult loci'. These feathers are most probably recently replaced for 3rd gen feathers.
Best of course is to witness / photograph the complete moult process throughout a period in ringed birds to exactly register the sequence...
Cheers, Mars
The white based scapulars with brown anchor patterns are worn 2nd gen feathers. But there are also a few scapulars with grey base and ill defined patterns, the fringes in better condition. For these feathers it is important to define the exact location.
a. The longest rear scapulars are grey based and look relatively fresh. They were replaced somewhere last in line, and this is exactly what you would expect when an ordinary sequence is followed in the scapular moult process. These are last replaced 2nd gen feathers.
b. But there are also a few grey based upper scapulars, at a location corresponding with the 'first moult loci'. These feathers are most probably recently replaced for 3rd gen feathers.
Best of course is to witness / photograph the complete moult process throughout a period in ringed birds to exactly register the sequence...
Cheers, Mars