22 March 2009

Brewer's Duck

I found a very interesting duck in Logan today, a "Brewer's Duck". The famous ornithologist John James Audubon described this species in 1840 on the basis of a specimen he collected in Louisiana. He mentioned that he had been unable to procure a second specimen, and that he thought this species was probably closely related to both Mallards and Gadwall. He was more right than he knew. We now know that this "species" is in fact not a species at all: it is a hybrid between a Mallard and a Gadwall.

I wasn't able to photograph the bird I saw, unfortunately. I got distant looks at it through my spotting scope, but as I moved closer to take some photos, it flew away to the south and out of sight. But, a very similar bird was found by Carl Ingwell and Jeff Bilsky less than an hour's drive from here on the Great Salt Lake exactly one week ago. (Photos of that bird are here. Edit - removed broken link; those photos are gone.) Could this be the same bird? We will probably never know, but I think it's likely given how relatively close the other sighting was in both time and space. I'll keep looking for the bird in the hopes that I can get a photograph, which might help us determine whether it's the same bird.

This hybrid combination is rare, as are all hybrid combinations. It's the rarity of hybrids that keep species discrete from one another. However, ducks are famous (or notorious) for the amount of hybridization between species, relative to other taxa. For example, see this blog post for a series of beautiful duck hybrids, including the Brewer's Duck. My favorites are the Mallard x Red-crested Pochard, and the Mallard x Wood Duck. Keep an eye out for unexpected hybrid combinations at a pond near you. You never know what beautiful combinations might turn up!

1 comment:

Ryan O'Donnell said...

Saw another Brewer's Duck yesterday, along with another very cool hybrid! See this post for photos.