Costa Rica bird (1 Viewer)

[Andy Adcock]

MacGillvray's warbler

So what age / sex is it?

It has to be a female so why the black spot?

 

[njlarsen]

Well the black spot is an issue then?

I think it is a young bird in its first winter which have started the moult towards adult plumage. Just like a summer tanager can have red spots on an otherwise yellow-green plumage during such a moult, I think this dark spot is the first part of what eventually becomes a full hood.

Niels

 

[49bentley]

So Niels are you thinking this to be a male MacGillivray's Warbler?

 

[njlarsen]

So Niels are you thinking this to be a male MacGillivray's Warbler?

I don't think I can be sure, but that is the way I am leaning.

Niels

 

[49bentley]

Thanks Niels.

 

[Andy Adcock]

I think it is a young bird in its first winter which have started the moult towards adult plumage. Just like a summer tanager can have red spots on an otherwise yellow-green plumage during such a moult, I think this dark spot is the first part of what eventually becomes a full hood.

Niels

It looks to be a female with the white throat and the supraloral line, it shouldn't have a black breast?

 

[njlarsen]

It looks to be a female with the white throat and the supraloral line, it shouldn't have a black breast?

Mostly in these wood warblers the young males are very similar to females. That was my thinking - and I don't deny that you have a different thinking.

Niels

 

[Andy Adcock]

Mostly in these wood warblers the young males are very similar to females. That was my thinking - and I don't deny that you have a different thinking.

Niels

Nothing to do with my thinking Niels, the OP looks like the female here so should not have a black breast spot?


http://www.paulnoll.com/Oregon/Birds/arrival-Warbler-MacGillivrays.html

 

[Kratter]

This is almost certainly a male MacGillivrays's , which have a grayish head (vs. more olive in female). In first basic (=formative) plumage, young male MacGillivrays's have a have a whitish throat, sometimes with some dark feather bases showing, with more coming in in the first alternate molt in March (fide Pyle).

Andy

 

[49bentley]

Thanks Andy.

 

[Birdingcraft]

A tough call and I'm not sure but am leaning towards Mourning because young males can show quite an eye ring and this bird seems to have that rather than the distinct, abrupt white crescents above and below the eyes. Unfortunately, just to make it more of a challenge, neither species can be discounted at that location.

 

[Andy Adcock]

Thanks Patrick.