Aythya sp.

[LMN]

Hi folks

I and a couple of friends saw this female Aythya at Stege slambassiner at the Danish island of Moen last 3rd of February '2007. At first glance it has similarities with Common pochard x Tufted duck but several features is not right. The bird has a lighter more grey brown colour and the difference in the back and flank colour is not as obvious. The size of the bird is intermediate between Tufted and Pochard. The head shape also differs by not being so edgy. The bird flew when we was waching it and showed no white in the wings.

If this bird is a hybrid involving Pochard and Tufted duck, it is probably not an F1 hybrid but rather (Pochard x Tufted) x Pochard. But it might also be a hybrid between Pochard and some other aythya eg.Ring-Necked Duck as it has some similarities to a bird, Canvasback x RND (number 182) in the Gillhams book: HYBRID DUCKS, THE 5th CONTRIBUTION TOWARDS AN INVENTORY.

please comment

Cheers

Lars Michael

[Nathan Kipling]

I would have thought the substantial amount of almost white around the base of the bill suggested some scaup influence.

[Josh Jones]

Aythya hybrids, my favourite!

Pochard has some influence here, but the second parent is not so clear. It could well be Scaup, the off-white colour around the base of the bill is fairly extensive (so perhaps too much so for Tufted Duck to be a parent).

Size-wise, it could fit both Tufted or Scaup (perhaps better so the former though due to a lack of bulk about the body?).

Given that this bird is in Denmark, I would imagine that one (or even both) of the parents being a Nearctic aythya is very unlikely, and so would stick with more familiar WP species for now.

You only have to look at how varied Ferruginous x Pochard hybrids are to realise just how much the appearance of hybrid offspring can vary!

[LMN]

Thank you for your answers.

I dint belive scaup is involved if this was the case i would expect a more rounded head shape. I have seen a male of this combination in the wild and seen the picture in the gillhams book.
I am quite familiar with the fact that hybrid offspring vary a lot.

cheers

Lars Michael

[LMN]

Just some additions. If Scaup was one of the parents i would expect some white in the wing. And the number i referred to in the Gillhams book is 128 not 182.

cheers

LM