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Age/sex W Marsh Harrier - France (1 Viewer)

Gduff

Well-known member
Photographed yesterday in West France.

From reading Forsman, I would say it's a 2 CY female individual
not juvenile because I can see moulting secondaries
not adult because the tail is dark brown, iris is dark
female because plumage is female/juv type, and silhouette is rather massive instead of slim and elongated

BUT:
i can see (pic 421) pale markings at the end of the upperwing greater coverts... indicating rather juvenile?
some pictures (403) show a grey (because of lighting?) tail, which would favor an adult?
Forsman writes that amount of pale underwing markings is very variable, even in juvenile
 

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Photographed yesterday in West France.

From reading Forsman, I would say it's a 2 CY female individual
not juvenile because I can see moulting secondaries
not adult because the tail is dark brown, iris is dark
female because plumage is female/juv type, and silhouette is rather massive instead of slim and elongated

BUT:
i can see (pic 421) pale markings at the end of the upperwing greater coverts... indicating rather juvenile?
some pictures (403) show a grey (because of lighting?) tail, which would favor an adult?
Forsman writes that amount of pale underwing markings is very variable, even in juvenile
2cy is correct. You can easily see that there are two generations of flight-feathers, so the bird has moult and/or is moulting, this exclude a juvenile.
 
This individual has both juvenile and moulted feathers, so the age (2cy) is easy. It is likely to be a female but on this we can't be certain indeed.
 
Last edited:
Photographed yesterday in West France.

From reading Forsman, I would say it's a 2 CY female individual
not juvenile because I can see moulting secondaries
not adult because the tail is dark brown, iris is dark
female because plumage is female/juv type, and silhouette is rather massive instead of slim and elongated

BUT:
i can see (pic 421) pale markings at the end of the upperwing greater coverts... indicating rather juvenile?
some pictures (403) show a grey (because of lighting?) tail, which would favor an adult?
Forsman writes that amount of pale underwing markings is very variable, even in juvenile
Marsh harrier is one of the most, if not the most, difficult species of raptor to age and sex in Europe.
The amount of contrast between the worn/old secondaries and the newly moulted in ones is so evident in this case that it should be a 2cy. The pale fringes to the secondary coverts are also present in non-juvenile feathers in female when fresh, thus these fringes are not a problem for a 2cy bird.
And, yes, based on structure (body size and a couple of other details) it can be reliably sexed as a female.
 

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