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Wild Neighbors: The Fine Points of Gull Identification: Why Bother?

By Joe Eaton
Thursday December 03, 2009 - 09:15:00 AM
A western gull, aggressively panhandling at Drakes Beach in Point Reyes.
Ron Sullivan
A western gull, aggressively panhandling at Drakes Beach in Point Reyes.

It’s been a long time coming, but there was one identifiable point in my life when I realized I was no longer a Serious Birder. That was two years ago, when Gulls of the Americas, a Peterson Reference Guide, was published, and I didn’t buy it. I still haven’t bought it. In fact, I passed up a discounted copy at the end-of-Cody’s sale. 

Not that it’s a bad book, for what it is. You’ll note that Houghton Mifflin called it a reference guide, not a field guide. This thing is a doorstop. The authors, Steve Howell and Jon Dunn, included detailed text descriptions and photographs for every distinct plumage of every species of gull that regularly occurs from Point Barrow to Tierra del Fuego, plus hybrids, waifs, and strays. That’s fine. I still don’t want it. I just can’t take gulls that seriously. 

I suspect the roots of gullmania go back to the ’70s, when the Thayer’s gull was elevated from a race of the herring gull to a full species, and birders had to work out its subtle field marks. Then came a spate of books, like the National Geographic guide and Kenn Kauffman’s Advanced Birding, that dealt with the plumage changes that gulls undergo as they mature.  

Birders began to go out of their way—to landfills, to the Great Lakes in winter—to see newly identifiable rarities. European taxonomists got into the act, splitting the herring gull six ways from Sunday. Some of the newly recognized taxa showed up in North America, and observers had to consider Vega gulls and yellow-legged gulls. 

The Howell and Dunn book is the logical culmination of those trends. They refer to “cycles” of plumage rather than “years,” and that usage has caught on. Last week, on one of the regional birding listserves, somebody reported a gull at the mouth of the Mad River as a probable first-cycle Thayer/Kumlien’s intergrade/hybrid. I applaud the observer’s field skills, but I don’t care. It was still a gull. 

Gulls have very little appeal for me, especially the big white-headed jobs: western, glaucous-winged, herring, California. 

They’re just feathered appetites: raucous, greedy, untidy—corvids without the smarts. You want to know how intelligent gulls are? More than once I’ve seen a western gull attempting to eat a starfish bigger than its head. The gull was standing around with one arm of the starfish down its throat, maybe waiting for the little sucker feet to lose their grip. Not the kind of thing a raven would try, even on a bad day. 

It’s not really about intelligence, though. Albatrosses can’t tell floating plastic junk from fish but that doesn’t tarnish their mystique. Terns, skimmers, jaegers, and skuas, all close relatives of gulls, are cool in their various ways. Even the smaller gulls have redeeming features: I’d love to see one of the polar exotics, like the ivory or Ross’s gulls, or the swallow-tailed gull of the Galapagos. But at this point in my life I wouldn’t go across town to see a slaty-backed gull, which is pretty much a western gull with a bit more white in its primaries. 

Did I mention that gulls hybridize at the drop of a hat? Western gulls have a 200-mile-long hybrid zone with glaucous-winged gulls on the Oregon and Washington coasts. Glaucous-winged gulls hybridize with glaucous gulls and herring gulls. Herring gulls also mate with lesser black-backed gulls and the California gull. 

Even without all that interspecific fooling around, the big white-headed gulls all seem to be very similar genetically. When biologists compared the genetic “barcodes”—snippets of mitochondrial DNA, inherited matrilineally and thus not affected by hybridization—of 643 North American birds, they found that eight large gull species, including western, glaucous-winged, herring and California were 99.8 percent genetically identical. (The flip side: the study found deep genetic divisions within such uniform-looking species as winter wrens, in some cases aligning with differences in song type and other behaviors.) 

So we’re talking about birds that, while separable in the field, may not even be valid species, depending on which of the many definitions of species you’re using. But the obsession persists.  

Another listserve had a lot of traffic recently about a lesser black-backed gull that had been spotted in Fresno County. After a couple of days, someone noticed that the gull didn’t look healthy. Then a message was posted that the bird had begun listing badly, and that birders who wanted to see it while alive and countable should hurry. I don’t doubt that some people charged off down I-5 to see the poor creature before it expired, which it did shortly after that posting. 

At bottom, I suspect, gullmania is an outlet for the kind of hypercompetitiveness to which birding has long been prone. Fine for the young and compulsive, but, as Mr. Goldwyn said, you can include me out.