Help with Bird ID please

To: David James <>, Mike Carter <>, Peter Madvig <>, M & P Potter <>, "" <>
Subject: Help with Bird ID please
From: Nikolas Haass <>
Date: Sun, 27 Nov 2011 13:55:44 -0800 (PST)
Hi David, Mike et al,

Yes, I spoke too soon. I agree with both of you that it is a second year pale 
morph Arctic Jaeger.
(Further reasons for it not being a Long-tailed Jaeger: the bill appears too 
long and the head not round enough)



Nikolas Haass

Sydney, NSW

From: David James <>
To: Mike Carter <>; Nikolas Haass <>; 
Peter Madvig <>; M & P Potter <>; 
"" <> 
Cc: Martin Cocker <> 
Sent: Monday, November 28, 2011 8:45 AM
Subject: Help with Bird ID please

I tend to agree with Nikolas that it is an Arctic, although I haven't any 
experience judging the amount of white wing flash in the folded wing of 
standing jaegers.
I definitely agreewith Mike that it is not an adult. Although the resolution is 
not great, it appears that the wing coverts and flight feathers are very worn. 
Conversely, the mantle feathers are a mix of worn and new feathers. The new 
feathers are darker with narrow white fringes. These are not retained juvenile 
feathers they are new feathers. They are not adult feathers because the white 
fringes are an immature trait that occur in juvenile, 1st and supposedly some 
2nd yr birds. Looks like some of the median coverts and the remainder of the 
mantle are newer than the primaries but older than the freshest mantle 
feathers. My interpretation is that the primaries, secondaries, greater coverts 
and tail are retained and worn juvenile feathers, the worn head and body 
feathers and median coverts are 1st winter/summer, and the new mantle feathers 
are 2nd winter. The bird must have hatched in mid 2009, as Mike determined.  
Mike, I hadn't notice the statement in Malling Olsen & Larsson that white tips 
to juvenile primaries are diagnostic of Arctic. It's a little hard to make out, 
but the last photo in that book is a juv Long-tailed with white tips to the 
primaries. In the  Windang bird I think the retained primaries are too worn and 
bleached to have retained any original white-tips. If there is a faint 
impression of pale tips it may be due to fraying and bleaching of the tips.  
David James, 


From: Mike Carter <>
To: Nikolas Haass <>; Peter Madvig <>; M & 
P Potter <>;  
Cc: Martin Cocker <> 
Sent: Sunday, 27 November 2011 11:08 PM
Subject: Help with Bird ID please

I agree with Nikolas
 that this is a pale morph Jaeger in very worn plumage, definitely not a 
Pomarine Jaeger, most probably an Arctic Jaeger rather than a Long-tailed 
(because of the pale blaze - but there is only a small amount of white at the 
base of the primaries which leaves me a little unsure). However, I have more of 
a problem accepting that it is an adult as the white spots on the mantle look 
to be remnants of juvenile barring the presence of which I can't explain in an 
adult. Perhaps Nikolas or others can. Therefore I would be happier considering 
this to be an 18 month old bird in second winter plumage, two or three years 
short of a full adult. But another perhaps age related feature is the white 
tips to the primaries. When in juveniles these white tips form a series of 
chevrons they are said to be diagnostic of Arctic Jaeger (Olsen & Larsson 1997).
Jaegers are notoriously difficult to ID and photographs of open wings 
particularly underwings are very helpful in this process.

Mike Carter
30 Canadian Bay Road
Mount Eliza  VIC 3930
Tel  (03) 9787 7136

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