Tuesday, April 10, 2012

GOLDENEYES

If you know the word "goldeneye" only from the book of the same name by Ian Fleming or the movie featuring James Bond, you're missing something. Goldeneyes are ducks! There are two species of goldeneyes, Common (Bucephala clangula) and Barrow's (Bucephala islandica), and they are among the most common wintering waterfowl in Puget Sound.

Male goldeneyes have black heads and backs and white sides, females brown heads and gray bodies. Their bills are short and high for a duck. Not surprisingly, they have bright yellow eyes. The males of the two species can be distinguished easily by the shape of the white spot before the eye and the relative amount of black on the back. Females are more similar, but their head shapes are different, Barrow's with a higher forehead and puffier crown. During late winter and spring, the bill of a female Barrow's turns orange, making identification easy.

Goldeneyes have relatively large heads and short necks, giving them a bull-headed look in flight. In fact, Bucephala means bull-headed. The males have big white wing patches, the females smaller patches. The wings of the males in both species whistle loudly in flight, and hunters call them "whistlers." We don't know the significance of the wing whistling.

Goldeneyes are aquatic predators, diving to the bottom to forage for invertebrate prey. Barrow's seem to specialize in bivalves, while Commons eat just about anything, including a variety of mollusks and crustaceans. This is manifested in their occurrence in winter. Commons are pretty much everywhere in salt water and fairly common in fresh water, as there is always something to eat.

Barrow's, on the other hand, are highly localized in salt water and quite scarce in fresh water. It makes sense; the mussel beds that Barrow's frequent are localized as well. Because they are more concentrated, you usually see Barrow's in larger flocks than Common. One place there are a lot of mussels is on clumps of pilings around docks and ferry landings, and those are the best places to look for Barrow's Goldeneyes, along with the Surf Scoters that take the same prey. The ducks have strong enough bills to be able to jerk mussels from the substrate!

Like most of our wintering waterfowl, these ducks pair in the winter, so by spring they are all in pairs, showy black and white males and more subdued brown and gray females. But there are still unmated males, so wherever goldeneyes hang out, watch for their spectacular courtship displays. The males throw their heads back while vocalizing and scoot forward on the water.

Both species nest in old woodpecker holes and tree crevices on freshwater lakes. Barrow's is fairly common on mountain lakes all across the Pacific Northwest, while Common is a more northerly species, relatively rare as far south as Washington.

Dennis Paulson


2 comments:

Anonymous said...

Goldeneye wasn't actually based on any of Ian Fleming's novels. The name of the film, however, did come from his Jamaican estate which was called "Goldeneye". It's also worth noting that John Gardner did write a novelization for said film.

Mama Bird said...

Yesterday (Jan. 20, 2015) we saw some ducks on some riverside ponds in the Willamette Valley in Oregon that I haven't been able to find in any bird book or online. They had black heads and white (or at least light colored) beaks. The bodies were lighter, some gray. Some might have been speckled. They were varied in size, with the larger ones having lighter-colored bodies. Some appeared to have reddish/buff colored patches on their backs. Any clues as to what this might be?

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