Your opinions on a possible Gadwall X Mallard, eastern Pennsylvania, Oct. 26 (1 Viewer)

[birdmeister]

Hello all,

I saw a duck at Green Lane Reservoir back in late October that struck me as odd. It was definitely mostly Gadwall, but a few features suggested Mallard hybridization to me. First, it had a striking yellow-buff head that contrasted sharply with a dark gray (sometimes green) crown, more so than any other of the 60+ Gadwalls present, male or female. In photos, the bird shows a hint of a pale neck collar. The last feature is that I think it had deep orange legs, unlike Gadwall's yellow-orange legs.

However, it did not show certain features of a classic Gadwall X Mallard, including:

pale on bill
different head shape
dark brown chest
any Mallard features on rest of body and/or tail


I have gotten a few expert opinions on this, and they ranged from "not enough to say either way" to "looks good for a hybrid", even "more likely hybrid than not, possibly a 2nd generation".

What are your thoughts on this? Likely a hybrid, or just a male Gadwall that's slightly off?

I am leaning towards some degree of a hybrid, especially considering that I could fairly quickly pick it out from the many Gadwalls it was with.

I'm attaching ten photos, all "phone-scoped" and not good quality.

 

[birdmeister]

Here are the rest of the photos.

 

[fugl]

“Two-toned” faces and white neck-rings are occasional plumage aberrations among drake Gadwalls. Here’s an example I photographed in Reno some years ago—

https://www.flickr.com/photos/fugl/3090429571/in/album-72157602221544709/

Here are some more (scroll to the bottom of the page to see them)—

http://www.birds.cornell.edu/crows/domducks.htm

 

[Joern Lehmhus]

Yes, I agree with fugl

Otherwise normal , standard Gadwall can have a twotoned head pattern such as your bird, birdmeister.

wether this occasional head pattern is the result of hybridisation many generations back in the past or wether this is a mutation in otherwise pure gadwalls, can not be solved at the moment I think.

What is clear about your bird and others, similar ones : they can not be first generation hybrids as the only unusual trait is the head pattern. In a first generation hybrid there should be several other points not in accordance with pure gadwall.

What is interesting though: these capped gadwalls seem to occur in higher frequency in North America than in Europe , according to pictures in the web.

 

[birdmeister]

Thank you both for your insights and additional pictures/links. They were much appreciated!