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.

Sunday, March 21, 2004

Long-legged Skeeters are Actually Crane Flies
Ro Wauer, March 21, 2004, The Victoria Advocate, © 2004

Crane flies are later than normal this year. But it seems that lots of things are later than usual this year. While crane flies sometimes appear in South Texas as early as late January or early February, the first did not appeared this year until March. I discovered a few crane flies, mostly paired, in weedy areas in my back yard. I did not find the huge numbers that occur at times. Huge swarms occasionally are found in cool, damp places, such as in culverts or under concrete bridges. Sometimes these swarms bob up-and-down, by raising and lowering their bodies by bending their long legs, in a really strange manner. This behavior is not well understood, although some entomologists suggest that it may be a way for the males, that dominate the swarms, to attract passing females. Others suggest that it is more related to safety-in-numbers. But whatever the reason, it is a little odd and also a little spooky.

Crane flies are those huge mosquito-like insects that, when flying about, are slow and clumsy, sometimes even bumbling into lights, doors, and even mouths of predators. These daddy-long-legs of the air have also been called "drolls of the insect world," due to their unassuming personality. They are not at all like most other members of the Diptera or the True Fly Family, that include such well-known creatures as the house fly, mosquito, fruit fly, midges, and gnats. Most of these other flies are sun-loving creatures. There are about 90,000 Diptera species worldwide, including almost 17,000 in North America. Dragonflies, mayflies, and stoneflies are not true flies.

All of the true flies possess a single pair of wings and a pair of short knobbed projections called "halteres," located on their bodies just behind the wings that serve as balancing organs. They are easy to see on crane flies, due to the insect's large size. Halteres act as a second pair of wings, like gyroscopes, vibrating rapidly in opposition to the insect's wingbeat; when the wings move up, the halteres move down. If one of the halteres is removed, the insect can no longer fly; it sideslips and yaws, out of control. In people, this sense of balance derives from structures in the inner ear. If something goes wrong with this mechanism, a person has difficulty in navigating, and even standing up.

Crane flies, unlike their mosquito cousins, have no sting or bite; they are totally oblivious to humans. One usually can get within a few inches for a close-up examination. Except when disturbed, they will stay in place. They can be described as having a narrow abdomen, narrow wings, and absurdly long legs. Occasionally they can be found walking about on tree trunks or logs or damp leaf-cluttered ground. Many of those found on the ground or on logs are males in search of a female. They may even sit beside a pupa until the female emerges and then mates, scarcely before she has freed herself of the pupal skin. The female crane fly, once filled with eggs, deposits them on the surface of rotting wood or pushes them into the soft pulp. The larvae, tiny greenish grubs, crawl about below the surface of the ground, feeding on roots and seedling plants, sometimes killing them. Although adult crane flies are most obvious and attract our greatest attention, the larvae, that are rarely evident, are biologically more important.

In spite of the relative unimportance of the adult crane flies, they are far more interesting at this stage than at the larval stage. Finding a swarm of these long-legged insects on some damp structures, or seeing several individuals flying about one's property on a warm spring day, seems to be a telling signal that the new season has truly arrived.

Tuesday, March 16, 2004

Bird Songs and Springtime
Ro Wauer, March 16, 2004, The Victoria Advocate, © 2004

Anyone wondering if spring has really arrived has only to spend a few minutes outdoors listening to the abundant bird songs. Avian vocalization has increased considerably during the last few weeks, so it is impossible not to notice. Perhaps our northern cardinal was the first to speak out, but several of the other full-time residents were not far behind. Now, any wooded area in the Coastal Bend rings of songs by chickadees, titmice, wrens, jays, mockingbirds, and doves.

Most folks pay little attention, and when asked to identify even the most common bird songs, readily admit they are birdsong challenged (I believe that is the current appropriate term). But yet, it would surprise those same individuals how many bird songs they already know. For instance, who doesn't recognize the "bob-white" song of a bobwhite quail, the "fee-bee, fee-bu" song of a Carolina chickadee, the "jay, jay, jay" song of a blue jay, or the "what, cheer, cheer, cheer, cheer, cheer, whot, whot, whot," or "birdy, birdy, birdy" song of the northern cardinal. And what about the "caw" of a crow or "teakettle" of a Carolina wren?

Birdsong can be difficult for even the avid birder. Even those of us who have been enjoying birdsong for many years can have problems in spring, especially when the neotropical migrants begin to arrive. Songs not heard since last year, or for several years for some species, can be difficult. Others can be easily recalled. The "pee-ah-wee, pee-err" of the Eastern wood-pewee, for instance, can hardly be mistaken. Warbler songs require an extra good memory to be able to identify each in spring. Although a few, such as that of a northern parula, is so distinct that the first song each spring is easily recognized. And what about the high-pitched calls of cedar waxwings?

The vast majority of South Texas birds possess a song, although fewer than half of the almost 9,500 known bird species actually sing. But many species possess a repertoire of songs, often singing different songs in order, one after the other. Our northern mockingbird has as many as 150 songs, while a brown thrasher can sing more than 3,000 song types. A European starling's repertoire may include as many as 67 song types. And many wrens, especially the tropical wrens, often sing duets, so that one individual begins the song and its mate ends the song.

Although most birds learn only the songs they hear from their own species, the mockingbird is an exception. It is estimated that only about 85 percent of a mockingbird's singing are "uniquely mockingbird," while the other 15 percent are derived from all types of sources. Those can include other nearby birds, a human baby's cry, an engine, a whistle, and an amazing assortment of other sounds. They rarely imitate extensive sounds, but rather simplify a phrase by utilizing only pieces. Mockers often imitate cardinals but seldom if ever imitate the more detailed and extensive songs of wrens.

How many songs do birds sing in a single day? That varies with the species. Ornithologist Margaret Nice recorded 2,035 songs in a single May day for a song sparrow. She also reported a black-throated green warbler that sang 1,680 songs in seven hours, and she estimated that on a typical day of 16 daylight hours he would have sung more than 3,000 songs. But the North American winner is the red-eyed vireo. Ornithologist Harold Mayfield recorded a Michigan red-eye which sang 22,197 songs in a day.

Biologists tell us that bird songs are utilized to identify the bird's territory, usually directed at other males, and to attract a mate. The song may also serve to convey a message. But whatever their purpose, most listeners appreciate birdsong simply for their acoustical quality. For many of us, it would be an empty world without the songs of birds. And who could enjoy a fresh spring day without birdsong?

Sunday, March 07, 2004

Hawk Nests are Built in a Variety of Locations
Ro Wauer, March 7, 2004, The Victoria Advocate, © 2004

A recently reported nest atop a utility pole along Loop 463, between Mockingbird and Ben Jordan in Victoria, is that of a red-tailed hawk. It is a huge nest, built of sticks, situated at the top of the pole. When I checked it out, an adult hawk was sitting on what I assumed to be a clutch of eggs. It probably is too early in the season for youngsters, although I suspect that hatching will occur any day. And then we can watch the adults bringing food back to the hungry nestlings.

The nest was first reported to be that of an eagle, but eagles do not nest in such locations, and most bald eagle nests, the eagle species that does nest in the Coastal Bend, would probably be considerably larger. In fact, one bald eagle nest in the East was measured at 10 feet across and 20 feet deep. Bald eagles often utilize the same nest for many years, normally adding several sticks to the nest every year. There are records of eagle nests becoming so large that they eventually break the tree branch on which they are built.

Hawks, including eagles, as well as some owls, such as great horned owls, are some of the earliest nesters. Already most of our local bald eagles have fledged young. Red-shouldered hawks have been screaming overhead for several weeks. Doves and pigeons are early nesters as well, although these birds will usually nest two or even three times each year. And many of the full-time resident birds are also nesting, or at least preparing to nest. Carolina wrens, Carolina chickadees, bridled titmice, northern mockingbirds, and northern cardinals are in full courtship mode. The neotropical species, birds that overwinter south of the border and spend only the breeding season in the U.S., nest somewhat later. Most of these neotropical migrants are only now, as the day lengths increase, getting the urge to head north. Many fly nonstop across the Gulf to Texas from Mexico's Yucatan Peninsula, while other take a land route.

Nest types vary considerably. Although the larger species, such as the hawks, build stick nests on poles, on tree branches, and even on ledges of cliffs when available, other birds utilize very different nests and sites. Many are cavity nesters, taking advantage of cracks and crevices in trees, cliffs, and even riverbanks. Examples of cavity nesters include many of our more common species, such as chickadees, titmice, bluebirds, martins, and woodpeckers. Kingfishers are also cavity nesters, actually constructing tunnels in dirt banks.

Cliff swallows construct closed nests of tiny mud pellets, usually placed under a concrete bridge or similar place. Although cliff swallows usually return to their natal nesting ground and often only restore last year's nest, a colony of these birds are just as likely to complete brand new nests in record time to lay eggs, fledge their young, and be heading back south within only eight or ten weeks.

Many other birds, including most of the neotropical migrants, build open nests in foliage or on tree limbs. In fact, 77 percent of all birds utilize open nests. Hummingbirds, for example, construct tiny thimble-sized nests of grasses and spider webbing on branches. These tiny nests are flexible so as the family grows the nests expand. Warblers, vireos, doves, thrashers, thrushes, and even finches utilize open nests.

There also are a number of birds that nest on the ground, some barely building a nest at all. Our common killdeer, for example, may only smooth out an area for a nest. Nighthawks practice a similar nesting regime. Quail, such as our bobwhites, also are ground-nesters. All of these usually lay numerous eggs and produce very precocial young, many able to run about within only a few hours after hatching.

The nesting red-tailed hawk along Loop 463 offers an exceptional opportunity. Most large nesting birds shy away from people. But here is a pair that has decided to share their lives with interested humans. But stay some distance away, like across the highway, so they will not vacate their nest.

Monday, March 01, 2004

Book Review
"The Road to El Cielo" is About a Superb, Isolated Place in Mexico

Ro Wauer, January 2004, The Victoria Advocate, © 2004

This marvelous book is subtitled "Mexico's Forest in the Clouds," providing a clue to an area in Tamaulipas that is considered the northernmost cloud forest. Although it seems remote and distant, the entrance to this unique region it is only a day's drive from the Border. The nearest village is Gomez Farias, about two hours south of Cd. Victoria.

"The Road to El Cielo," written by Fred and Marie Webster of Austin, contains some truly wonderful descriptions of the region, including details of the routes to the heart of the El Cielo area, Rancho del Cielo. This site is surrounded by forest, where Marie conducted a series of breeding bird surveys during the 1940s and 50s. Since then, Christmas Bird Counts have been undertaken in the area almost every year. Four years ago, I participated in one of those counts, staying at the rather rough accommodations at the Rancho. It was a great experience there among oak-sweetgum woodlands in the highlands on the Sierra de Guatemala.

Fred and Marie first visited Rancho del Cielo in 1964, where they met a Canadian immigrant Frank Harrison, who had settled there and carved out a small clearing where he raised his own food. They fell in love with the area on that first trip and returned on many occasions. Their book discusses their various trips and the changes that occurred within the region. They document the invasion of loggers and farmers that began to severely impact the wild character of the landscape. Harrison was eventually murdered by a party of the "agrarians."

The Websters tell a fascinating story about the efforts to protect this unique environment. In spite of the difficulties of protecting land in Mexico, the State of Tamaulipas eventually established a 360,000-acre El Cielo Biosphere Reserve, a United Nations designation. A Biosphere Reserve includes a fully protected core area and surrounding land with villages and activities that provide work related the protection of the core resources.

For birders and other nature lovers, "The Road to El Cielo" is a must-read. It offers an entertaining and informative account of a magical place. Their descriptions of the bird life, the abundant mammal predators that roam the forest, and the vegetation offer insights into an area of Mexico that few Norte Americanos have any knowledge about. Their adventures into the mountains, their struggle to help preserve the land, and their contacts with the friendly and not so friendly folks of the area make it a most enjoyable read.

"The Road to El Cielo" contains a forward by an eminent scientist who has studied the region, Dr. Paul Martin, as well as 27 line bird drawings by Nancy McGowan who also provided excellent drawing for a couple of my book. This book ($34.95, hardcover) was published by the University of Texas Press (ISBN 0-292-79149-2), but is available in Victoria at Tricia's Antiques and Gifts at 117 John Stockbauer.

The Websters firsthand reporting, enlivened with vivid tales of the people, land, and birds of El Cielo, adds an engagingly personal chapter to the story of conservation in Mexico.