March 27, 2008

Sea Gulls Not On Sea

Stupid Question ™
Jan. 20, 2000
By John Ruch
© 2000

Q: Where do the flocks of sea gulls on the Olentangy River in Columbus, Ohio come from? We’re hundreds of miles from the sea!

A: Today’s lesson: The human name for an animal doesn’t affect its actual origin and behavior.

“Sea gull” is a generic popular name, not a scientific one. There are actually many types of gulls. Many of them are indeed ocean shorebirds. But many also live on freshwater lakes and rivers far inland.

In fact, the “sea gull” is the state bird of Utah—and the subject of a Salt Lake City monument—because insect-munching California gulls saved the Mormons from an 1848 grasshopper plague.

Large numbers of gulls breed in the big lakes of Canada and the northern U.S.—including Lake Erie, which is probably where most of ours come from. They frequently travel down America’s great waterways, such as the Ohio and the Mississippi.

Two types of gull frequent Columbus’ rivers, reservoirs, farm fields and shopping mall parking lots. The most common is the ring-billed gull, which is crow-sized, with yellowish legs and black spots on its upper and lower bill that look like a vertical ring. They can be greedy eaters; several have been found choked to death after trying to swallow dead squirrels too big for their throats.

Around 1900, ring-bills didn’t even breed on Lake Erie, but their population has skyrocketed with the increase in human garbage dumps and fast-food litter on which the gulls scavenge. (Metro Parks naturalist Andrea Haslage calls the ring-bill “a suburban bird.”) Today, they’re actually more common inland than on seacoasts.

In the winter, they can be found as far south as Mexico and as far inland as Kansas and Colorado.

Less common is the larger, pink-legged herring gull (which, 100 years ago, was more common than the ring-billed gull). Herring gulls are able to drink either fresh or salt water, and are known for breaking clams open by dropping them onto rocks from the air.

No gulls breed around here, so all the ones we see are visitors. Exactly why they’re visiting, however, is hard to say. Most gulls do make seasonal moves north and south, but they’re not hardcore migrators. They’ll happily hang around any place that has some open water and plenty of food (so mild, ice-free winters keep them around longer).

A bird’s age may affect how long it hangs around (though experts can’t agree on whether younger or older birds are more likely to do so).
Gulls definitely head north in the spring, since they always return to the same breeding grounds. Gulls too young to breed spend more time wandering around.

And in general, gulls are known for flying considerable distances scouting for food. Some of our gulls may simply be making a day trip from Lake Erie.

Whatever the individual reasons, gulls are most common in Columbus during the spring and fall quasi-migrations, but can be found all year ’round. (I saw 30 of them Sunday at Antrim Park.)

As Metro Park’ Haslage says, “If there’s open water, they’ll be here.”

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