On the Fly — Odd Ducks

My friend Mary Jane and I spotted the first duck pictured here at the Martinez Shoreline Park in 1999. She named him Pushkin, for his headgear—any Russian name would do, and that’s what came to mind. He was around for several seasons, and then we didn’t seem him anymore.

The duck in the second photo, also a denizen of the Martinez shoreline, was around for a while in 2007 and 2008. I named her Oddrey, for obvious reasons. Then I found a postcard from the fifties titled “Powder Puff Duck” featuring a similar but all-white bird, and I saw that this was not just a local phenomenon. For a dozen years, with occasional reminders, I’ve been wondering what was up with these crested creatures. And this week I finally found out.

What we have here is not Martinez’s answer to Blinky, the three-eyed goldfish that swims just outside the Springfield nuclear power plant. It’s normal for a duck to sprout a fountain of feathers on its head. It turns out there’s a defect in the skulls of some ducks, an opening that encourages these fluffy outbursts, and some breeders select for it.

This was a little disappointing. Ducks are the animal version of the squash family, crossbreeding easily and producing all manner of interesting offspring. So I had imagined our crested wonders coming from the genes of exotic birds passing through on the flyway, or at least unexpected liaisons between mergansers and mallards. But no, they’re either domestic ducks that were dumped at the park or throwbacks to domestic ducks.

All domestic ducks are descended from mallards or muscovy ducks, and mallards (Anas platyrhyncos) interbreed with ducks of different species. As we learned in school, mules and other creatures that come from parents of the same genus but different species cannot reproduce. But mallard hybrids often can. So much so that in New Zealand they’re considered an invasive species, and in Florida it’s illegal to keep domestic mallards for fear of further polluting the gene pool of the region’s native mottled duck.

It’s confusing, I know. How can the snowy white residents of old MacDonald’s farm be related to mallards, with their iridescent flashes of green and purple, their handsome compositions of brown, beige, white and black? All-white creatures have a hard time surviving in the wild, so that trait is rare. And we humans, with our taste for the unusual, have managed to selectively breed mallards till they consistently come out looking like Huey, Dewey and Louie.

So if you are down at the local pond and spot a duck that looks unlike anything you’ve seen before, there are a few possibilities. If it has a crest or if it's all white or has asymmetrical white blotches, it is very likely a domestic duck that’s been dumped or there’s a domestic duck somewhere in its ancestry. It could be a partly albino wild duck, but that’s rare. Your odd duck could be a hybrid of wild ducks, especially if it has symmetrical features: it could be a cross between a mallard and a northern pintail, for example, or a wigeon or a gadwall. If it has those tightly curled tail feathers above its rump for which the D.A. haircut was named, you can bet there was a mallard involved.

These strange birds may be domestic but they are still fabulous (see photos 3, 4 and 5). Don’t give up: You might get lucky and see a truly uncommon visitor, such as the harlequin duck that’s been hanging around at Point Richmond this year.

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The East Bay Regional Parks have a Thursday birding program once a month. On May 26 will be a raptor baseline trip on the Marsh Creek Regional Trail, where you can help park staff document the variety and number of raptors on the east side of Mount Diablo. “No experience necessary,” they say. “We’ll teach you how to identify these birds.” 9 to 11:30 a.m., registration required: call 1-888-327-2757.