Identifying all of the world's gull species, travel aside, sounds like an impossible task.
OK, not impossible. But nothing to bet your life on. Too many species are, at first glance, look-alikes.
Finnish birder/photographer Klaus Malling Olsen will help you do that, however, with his new guide book, "Gulls of the World, a photographic guide."
There are only a few more than 50 gull species, total. Smallish number notwithstanding, they pose, according to the publisher, "some of the greatest field identification challenges of any bird group."
No kidding.
The problems are age-related plumage changes, variation within species, hybrids, and complex distribution.
ID disagreement is not uncommon, even among gull fanciers, like those who shiver on Lake Harriet's shore in late-fall twilight. Prior to ice, they are watching gulls return from garbage-dump scavenging, coming for nighttime roost.
In recent Novembers birders have been watching for Lesser Black-backed Gull, an unusual but recently regular visitor with deceiving plumage. (It frequently is seen, so observers say, but very hard to pin-point with a pointed finger.)
The book, from Princeton Press, is 368 pages, about six pages per species, with ample text, excellent photos, and well-done maps. (The maps do not show Lake Harriet, however.)
Gulls are interesting birds, mostly common in appropriate habitat, mostly easy to find and see.
The challenge, of course, is giving the bird its proper name. Olsen here gives you a guide to help with the challenge.
Gulls do appear out of range, like here, just often enough to often make second looks count. Being familiar with North American species could be helpful.
Gull photos in this book (and others) are, for good reason, well-lit closeups of individuals. How else to capture ID variances?
There are photos in Olsen's book, however, that capture the essence of gull — birds in flocks loafing on a beach, in the air, a cloud of gulls following a fishing boat. Gulls individually are to be identified. Gulls in a flock are to be enjoyed.
There are the usual guide-book aids to bird shape, and the wide variety of plumages defined by gull age and molt pattern. The intro text defines this book as a "concise companion" to an earlier gull guide by Olsen and Hans Larsson.
(Princeton University Press, hard-bound, index, maps, hundreds of photos in color, published in April, $45.)
