SCOTT SHALAWAY Where the gulls are -- and why

Almost every year, shortly after Christmas, I get letters and e-mail sounding something like this: "While at a shopping center recently, the parking lot was filled with sea gulls sitting in the snow and swarming around the cars driving by. As beautiful as the birds looked in the falling snow, I was astounded. So were all the other people watching them. No one had a logical explanation. Could you please explain why we saw sea gulls in winter so far from the ocean?"
Of the 20 or so species of gulls that inhabit North America, most live and nest along coastal areas. Anyone who has vacationed along Atlantic or Pacific beaches has certainly been entertained by gulls. But more than a few species occur inland as well.
Franklin's gulls nest on the prairies of the northern Great Plains. Bonaparte's gulls (named after a French zoologist who happened to be a distant cousin of Napoleon) nest on the edges of the boreal forest near lakes and bogs in Canada and Alaska.
Unlike most gulls, which nest on the ground, Bonaparte's builds its nest on a horizontal branch of a coniferous tree. California gulls nest near lakes throughout the inland west. This is the bird that rescued the Mormons' crops from a grasshopper plague in 1848. It is the state bird of Utah and honored by a monument in Salt Lake City.
Where they nest: Ring-billed gulls nest throughout the Great Plains and Great Lakes area, and their range seems to be expanding. And herring gulls occur across the northern third of the continent. They are especially common and widespread in the northeast.
Though the term "sea gull" is commonly used to describe all gulls, it's obviously a misnomer. Most gulls do, however, winter along coastal areas.
Franklin's gulls migrate all the way to the west coast of South America. Many other species spend the winter along southern U.S. coastal waters.
Ring-billed and herring gulls winter along the shores of both coasts and the Gulf of Mexico, and they also venture inland along major river systems. These are the gulls we see in winter. Winter range maps for these species follow the Mississippi River and its major tributaries all the way to the Great Lakes.
Ring-billed gulls are about 18 inches long and have a four-ft. wing span. The yellow bill is encircled by a prominent black ring near the tip; hence its name. Herring gulls are larger -- about 25 inches long. And their wings span nearly five feet.
Sightings: Most winter gull sightings occur near major rivers. The observation reported in the opening paragraph was along the Ohio River near Pittsburgh. I've had other reports of gulls along the Ohio River near Wheeling and from Illinois near the Mississippi River. Usually these reports are of large numbers of birds. That's probably why they're noticed.
Another reason we see gulls so far inland is that they have adapted extremely well to human disturbance. Gulls are scavengers; they eat just about anything. Ask anyone who has tried to picnic on an Atlantic beach. Laughing gulls, in particular, can be real pests. They seem to think we created garbage dumps, landfills, and fast food restaurant dumpsters as feeding stations just for them.
In nature, gull eat fish, carrion, insects, mollusks and crustaceans. Some gulls carry hard-shelled mollusks high into the air and drop them on rocks to break them. Others can be surprisingly predatory. The great black-backed gull, for example, is the largest gull in North America and also eats rodents, small birds, eggs and chicks
. A few years ago off the Maine coast, I saw one of these predators in action. It sailed over a raft of common eiders (a type of sea duck), dropped into the flock, picked up a duckling, and swallowed it whole.
If you see gulls in what seems unusual places this winter, you're not alone. But look around for the reason. You're probably within a few miles of a major river or lake, and there's probably an open dumpster nearby.
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