The Nature Writers of Texas

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

Sunday, March 28, 2004

Wildlife Favorites and Otherwise
Ro Wauer, March 28, 2004, The Victoria Advocate, © 2004

I often get asked what my favorite bird or butterfly or other wildlife might be. And each time I have to admit that I do not have a favorite. I guess I have a few species that I enjoy seeing more than others, but I really don't have a favorite. My wife, on the other hand, has a favorite bird, the painted bunting. I admit it is a gorgeous creature with its striking pattern of reds, green and blues. But to me it is rather gaudy, not one that could possibly be a favorite. I much prefer, in fact, the more subtly colored varied bunting.

As for butterflies, I guess I like the hairstreaks as much as any other group, but not a single species. Most of the hairstreaks are little, and people not watching for butterflies are likely to miss them altogether. But to me, they are a fascinating family, with their little tails and habit of rubbing their hindwings together. Their behavior suggests that their tails are antennae, so a predator is more likely to attack their less vulnerable rear end rather than their head. And one of the dullest of the hairstreaks - the gray hairstreak - will never win a butterfly beauty contest, but it does very well nonetheless. It is one of the most widespread butterfly species in all of North America.

Is there also an avian example of dullness? I suppose if required to name one, I would select the willet, a shorebird common along the Gulf Coast in winter. Although it is a fairly large bird, half again larger than the common killdeer, it seldom gets much notice. Except in flight, when its black-and-white wing pattern is obvious, it is largely ignored. The other exception is when someone gets too close, the willet can be a real loudmouth, with its penetrating calls of "pill-will-willet." The plumage of wintering willets is mostly dull gray with a dark bill and gray legs. Not a real attractive bird.

The advantage of a dull appearance is its ability to go unseen, to blend into its environment so that a predator is likely to pass it by when searching for prey. Many of the shorebirds possess similar characteristics. It is amazing how difficult it is to locate one of these nondescript birds on a broad plain. Even gulls, especially immature birds that still possess juvenile plumage, often blend in perfectly with the landscape. The patterns of many inconspicuous birds, shorebirds in particular, is known as "countershading," darkest on the back and gradually becoming lighter until the belly may be pure white.

Other species, such as killdeers, possess "disruptive" coloration, the use of striking patterns to break up the bird's outline. The extreme in cryptic coloration would be a bird, such as a ptarmigan in winter that possesses plumage the exact same color as its snowy surroundings. And some butterflies blend in so well with their substrate that unless one is able to see it in flight before landing, it can be next to impossible to find it once perched with folded wings. The leafwings, such as the goatweed leafwing that is common in the Coastal Band, is a great example. The underside is gray-brown, while the upperside is bright orange.

Several more tropical species, such as the bluewings and beauties, possess an underwing pattern and color that have evolved specifically to camouflage the bearer. The patterns on some mammals, such as spotted cats, have the same purpose.

On the other hand, there are lots of wildlife species, like painted buntings, that stand out among all its neighbors. Female painted buntings, however, are greenish, so that they blend in very well with their greenish environment.

Although the gaudy males do not blend in well, their strategy is designed to be so attracting that a mate can hardly pass them by. Hummingbirds also utilize this same technique; male hummingbirds possess brightly gorgets while the females are dull. Apparently, both methods work reasonable well. Painted bunting and hummingbird populations, as well as those of willets, killdeer, and gray hairstreaks are doing very well.

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