The Nature Writers of Texas

The best nature writing from the newspaper, magazine, blog and book authors of the Lone Star State . . .

Sunday, January 16, 2005

Geese are Especially Abundant this Winter
by Ro Wauer

On a New Year's Eve trip to Baytown, as well as on various local Christmas Bird Counts in late December, I was reminded once again of how important the Gulf Coastal area is for wintering geese. Watching thousands of geese lifting off of their roosting sites during the dawn hours, or seeing numerous lines or geese stretched out across the sky, is truly exhilarating. On many of those occasions, the numbers visible at one time can be overpowering. Guessing their numbers is difficult at best. Our Gulf Coast geese populations arrive as early as mid-September but are mostly gone by May. But during their seven-month residency, they offer one of Mother Nature's most impressive sights.

Four kinds of geese overwinter in the Central Texas Coastal area - snow, Ross's, greater white-fronted, and Canada - although a couple others are possible. Snow geese are our most abundant species, and are easily identified by their overall white plumage, pinkish bill, and "grin patch," the strongly curved border at the base of the bill. In flight, however, their black wingtips, including their primaries and secondaries, are also obvious. Snow geese also possess a "bluish" phase that can be confusing when scooping a large congregation or observing a flock in flight. Juvenile blues can be overall dark gray-brown, but adults possess a white head. These blue morphs were once considered a separate species called a "blue goose." Snow geese breed on the high Arctic tundra.

One cannot help but wonder, since these two color phased birds are the same species, why they all do not become all white or all blue. Kent Rylander, in his excellent book, "The Behavior of Texas Birds," points out that geese normally select a mate of the same color. "One interesting hypothesis proposes that sexual imprinting biases a bird to select a mate of its own color. Thus juvenile geese, because they imprint on their parents at an earlier age, are biased toward selecting a mate of their parent's color."

Ross's geese are very similar to snow geese, and they occur together during the winter months. It can be difficult to pick out a Ross's goose among a huge flock of snows, but a Ross's goose is smaller and possesses a shorter bill and rounder head. It also lacks the snow goose's "grin patch." Ross's goose was once considered rare in Texas, but it has become reasonably common in recent years. Almost any large flock of snows contains several Ross's geese. Ross's, like snows, also breed in the high Arctic, but prefer lake islands rather than open tundra ponds.

White-fronted geese can also be abundant in our area in winter, although they often are not as dependable as snow geese. White-fronts are somewhat larger than snows, possess overall gray-brown neck and underparts with black barring, a white belly, pinkish bill, and a white face, hence its "white-fronted" name. White-fronted geese breed in northern Canada and northwest into Alaska.

Canada geese may be the best known of our wild geese all across North America, but this species usually is less abundant in winter in South Texas. It is more common further up the coast and inland. In appearance, it is similar to white-fronted geese, but Canadas have a distinct black neck and head with snow-white cheeks (chin-strap) and a pale breast. Size generally is similar to that of snow geese, although they vary considerably. And this is the only wild goose that is known to breed in Texas; it has recently become a summer resident in the Panhandle. According to "The Handbook of Texas Birds," "some recent breeding records involve pairs where one individual was known to be injured." This species breeds all across North America, and has become a nuisance on golf courses throughout. These are highly gregarious birds that readily habituate to humans, making themselves at home in many urban situations, especially if they are regularly fed.

One of our most enjoyable outdoor experiences this time of year is to drive our roadways, watching for flocks of geese. Our coastal fields and wetlands contain some of the highest populations of wintering geese anywhere in the world.

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