The Nature Writers of Texas

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

Sunday, November 27, 2005

Bluebirds are with us for the winter
by Ro Wauer

Bluebirds and robins seem to have a lot in common; they are two of our best known songbirds. And both of these lovely creatures are commonplace again. We can pretty well depend upon them to be with us throughout the winter months.

Although bluebirds are resident in much of South Texas year-round, they are far more numerous in winter than during the warmer days of summer. Our bluebirds, actually Eastern bluebirds, are a good example of "winter Texans," moving south for the colder months to increase the resident populations. The majority of the northern birds will be with us through March before they move northward to their breeding grounds. Others may actually nest and raise a family before they go north.

Our Eastern bluebird is a lovely creature. Males are especially colorful with a bright blue back and rufous chest and throat. Females are a duller color. The male's rufous throat is what sets it apart from the Western bluebird that possesses an all-blue head and throat, but only rarely gets to South Texas. And a third bluebird, the mountain bluebird, is also occasionally found here. Male mountain bluebirds are a sky-blue color. While females are a duller gray-blue.

All bluebirds are cavity nesters, utilizing holes in trees, posts, and other sites. They also utilize birdhouses placed at strategic locations at the edge of fields. They will not utilize houses in or facing nearby wooded areas; they rarely spend much time in locations without adequate open space. All bluebirds are insect-feeders, utilizing grasshoppers, crickets, and a wide assortment of other insects, as well as various other invertebrates. But in winter they often feed on berries.

Bluebirds are members of the Turdidae family, along with robins and thrushes, some of our most vocal songbirds. Although bluebirds can hardly compete with such marvelous songsters as the hermit and wood thrushes, their springtime song is still rather enchanting, like a musical "chur-lee chur-lee." In winter they rarely sing, but their call notes, a rising "chur-lee," is often commonplace. They call from either a post or in flight, and often times one can detect their presence long before they fly by. Both their songs and calls are most pleasant.

Few birds are so well known and appreciated as bluebirds. Yet, because they depend primarily on insects for food, they are extremely susceptible to pesticides. Their survival depends upon our prudent use of these poisons. In some areas where their numbers have declined, bird lovers install "bluebird boxes" along fence lines and at other appropriate places. This practice has greatly enhanced their numbers. Increased numbers of bluebirds, at any time of the year, will not only help in keeping insect pests under control but also add to our enjoyment of one of nature's most lovely creature.

Sunday, November 13, 2005

Fall Color is Possible in South Texas
by Ro Wauer

One of my earliest memories of being raised in Idaho and Utah was the color of aspens on the mountainsides in fall. Great blotches of golden-yellow would dominate the landscapes, and I realized that winter was soon to follow. That brought snow and cold, but it also offered skiing, skating and sledding. Those activities also are but a memory, many of which I would as soon forget. And now living in South Texas, where fall color is barely noticeable, and snow is restricted to those very rare occasions, fall and its attributes require a little more imagination.

Fall color does occur in South Texas, however, although it is more subtle than it is to the north. Some of our broadleaf trees, such as some oaks, pecans, sycamore and cottonwoods, cypress trees, as well as a number of shrubs, do change color in fall. The reasons for the color change in our vegetation are the same as that to the north. It primarily is due to chemistry. Tree expert Robert Bartlett explained the process this way: "As summer wanes a band of tiny cells at the end of a leaf stem, where it hooks onto a twig, begin to dry and harden. This stops up the plumbing system inside the leaf. The manufacture of sugar slows down and the green chlorophyll no longer reaches the leaves. Now yellow pigments that have been masked within the leaves all summer are revealed. The red pigments are manufactured and the trees take on a kaleidoscope of hues and tones, a harmony of color."

Some of the eastern Native American tribes had a very different perspective on the fall color. They believed that leaf changes were due to celestial hunters who killed the Great Bear and that his dripping blood fell onto the forest trees, gradually changing the leaves to various shades. And although "Jack Frost," or the actual occurrence of frost, has little to do with the changing colors, weather is involved. If the fall is rainy, cloudy, or very hot, the foliage generally becomes bland, yellowish, or less vivid. Sugars, which are manufactured by the leaves, are transported down into the trees where they have little effect on fall foliage.

Locations and genetics are also significant in leaf color. The southwestern side of a tree usually has the deepest color since it gets more sunshine. And trees in lower places may show color earlier than those in higher spots if cold air settles in the low spots on still nights and the cooler temperatures trap sugar earlier. Genetic differences are also important. Typical red leaves are found in maples, dogwoods, and red and scarlet oaks, Browns and oranges are typical for white and black oaks, hickory, and hornbeam, while yellows are more prominent in cottonwoods, pecan, redbud, and elm trees.

Even though our fall colors are less dramatic than they are to the north, they still represent a change in season, a time to appreciate the end of hot weather and the beginning of mild winter days.

Wednesday, November 09, 2005

Cross Timbers Wildlife News
Fly Up the Creeks
By Jim Dillard, Wildlife Biologist, Texas Parks and Wildlife Department, Mineral Wells

Creeks are wonderful places here in Cross Timbers Country during the summer. By escaping to the shadowy canopy of towering pecans, elms, oaks and cottonwoods that hug their banks, one can find at least some relief from the heat that parches this land of sand-rock, woods and grass. Although most creeks here are intermittent, those that run year round or have deep pools of water that persist during dry spells are a Mecca for wildlife and me. Indians that occupied this region in bygone days were also drawn to the creeks for their sustenance. Today, the riparian zones that border these ribbons of life are some of the most ecologically diverse and yet most environmentally sensitive lands in Cross Timbers Country.

I spent a lot of time in my youth tromping up and down creeks in the Blackland Country of Central Texas. Although my motivation for going to the creeks was usually to hunt squirrels or fish for a mess of channel cats, their lure was strong and inviting. There was something magical about them that drew me back time and time again. Now, they’re only creeks in my mind, but the lessons I learned there about wildlife and land inspire me to this day.

One memory is of the fly-up-the-creek bird that I often encountered on my forays to the creeks. At least that’s what old man Springer called them and who was I to question old man Springer. He spent most of his days sitting, spitting and watching my dad pound away on the anvil down at the blacksmith shop. In his youth, he also had done his fare share of hunting and fishing on the same creeks I was then. “Yes sir, those fly-up-the-creek birds always fly up the creek, never down the creek,” he’d said. Why they did he wouldn’t say and I didn’t ask.

Fly-up-the-creek birds go by other more common names such as green heron, little-green heron, green-backed heron, green bittern, crab-catcher, skeow, shitepoke and swamp squaggin – green heron (Butorides virescens) works for me. They’re found primarily from southern Canada to northern South America and throughout the eastern half of the United States and along the Pacific coast to Baja. During winter, most birds migrate to the southern U. S. or south into Mexico.

Feather coloration on their back and wings is dark bluish-green; underparts are brownish-gray. Neck feathers are sorta chestnut-maroon color. Their shaggy head crest is dark and is often erected when they’re alarmed. Their relatively long legs are yellowish or orange. Overall length is one and one-half to two foot and wingspread about 26 inches. With the exception of the least bittern, it’s our smallest heron species, weighing in at five to seven ounces. When sitting motionless, they’re hard to see due to their blend-in coloration. Flush one and they’re likely to fly up the creek with a loud resounding skeowww – skeowww! They also make a series of kuk-kuk-kuk-kuk calls.

Habitat for these crow-size herons is muddy streamsides of creeks and rivers, swamps, marshes, lakes, ponds and other wetlands where they feed on a wide variety of aquatic life. Amphibians, reptiles, small fish, crustaceans, mollusks, insects, spiders, worms and small mammals are on the menu for green herons.

They’re one of the few species of birds known to use bait to lure fish into striking distance. They’ll drop things like insects, earthworms, twigs or feathers on the water surface and wait until a fish comes to investigate and then grab and gulp it down. They’ll also hunt from low branches or limbs over water and catch prey with an explosive jab of their sharp bill or dive right in to pursue their victim. Usually, they’ll just stand motionless along the shoreline waiting for something to pass by or shuffle their feet to stir something up. When walking, they nervously flick their tail while they raise and lower their head crest feathers.

For the most part, they lead solitary lives but may nest in loose colonies. During the breeding season, males will select a nest site and then go through elaborate courtship displays to attract a mate. If he’s the one, he’ll then bring nest building materials to the female and she’ll build a small platform nest to her specifications. In it she’ll lay four or five pale greenish-blue eggs that they both help incubate for about three weeks. Young are fed regurgitated cuisine by both parents and leave the nest in another two weeks. They hang around near the nest for a couple more weeks begging handouts from mom and dad before flying up the creek on their own.

I guess I was lucky to have had several creek bottoms within bicycle-riding distance from the town where I grew up to poke around in. It’s too bad that a lot of young folks these days don’t have access to a creek with critters to help them channel their lives and develop an appreciation for the natural world around them. And by the way, I once saw a fly-up-the creek actually fly down the creek. I wonder what old man Springer would have said about that. I wouldn’t have the heart to tell him. Until next time, I’ll see you down the road and God Bless America!

Sunday, November 06, 2005

Butterfly Numbers Peak in Early November
by Ro Wauer

For those of us who enjoy butterflies, early November days offer the highest numbers for the year. Butterflies present at this time of year usually include those species that have been present most of the season as well as strays from elsewhere, a few fall-only species, immigrants moving southward, and our lone migrant, the monarch. On a good sunny day in early November it is possible to find up to 50 species in our area.

The secret to finding butterflies is one or a few places to visit where nectaring plants attract and hold the passing butterflies. Even the travelers must stop occasionally to feed. So choice nectaring plants this time of year, such as flowering cowpen daisy, crucita, duranta, lantanas, Mexican heather, Mexican milkweed, palmleaf (Gregg's) eupatorium, penta, and tropical sage (my favorites), are the key. Especially crucitas (Eupatorium odoratum) are marvelous butterfly magnets in fall.

Besides the migrating monarchs, immigrants moving southward can make up a good number of a population. Most numerous of these are the painted ladies, the only butterfly species know to occur world-wide; red admiral, one that often stays around most of the winter months; and some of the larger sulphurs, such as cloudless and large orange sulphurs. Other wanderers, oftentimes strays from the south, can include rounded metalmark, julia heliconian, common mestra, and dorantes longtail.

Also in fall, a few temporary colonists, such as zebra heliconian and white peacock, can put in their appearance. Temporary colonists are a fascinating group of butterflies. They include species that cannot be expected on a regular basis, but only after a year when a stray female from another location happens upon a larval foodplant on which to lay eggs, the eggs or caterpillars overwinter, and adults appear the second year. They may breed again for another year, or several more years, before a colder winter occurs to destroy the population. An example is the zebra heliconian population that we had the last two years apparently got wiped out by last year’s Christmas Eve snowstorm. It is very likely, however, that additional strays will reach our area again this fall.

Butterfly populations usually are dominated by the full-time residents, although numbers of each species will vary, depending upon emergence cycles. But in general we can expect constant numbers of pipevine and giant swallowtails; little yellow; dainty sulphur; gray hairstreak; dusky-blue groundstreak; gulf fritillary; phaon crescent; common buckeye; goatweed leafwing; white-striped longtail; coyote cloudywing; long-tailed, sickle-winged, clouded, fiery, dun, eufala, and ocola skippers; common and tropical checkered-skippers; whirlabout; southern broken-dash; and sachem.

Many people first learning butterflies are surprised at the large number of the very small and tiny butterflies, species that are easily ignored in favor of the larger and showy species. Their small size also makes them difficulty to see. But with the advent of close-focusing binoculars, those can focus to six feet or less, even the smallest butterflies can be seen well enough to identify. And without seeing the butterfly's pattern, it is next to impossible to identify many of the smallest ones. For many of us watching butterflies, the smaller species, such as the hairstreaks, blues, and many of the skippers, present a challenge that is akin to identifying sparrows in a field of ducks and blackbirds.

Yet fall is a marvelous time to learn butterflies, as a single garden can attract a wide variety of species. That makes learning easier when one can be compared with another. And for those readers that are just starting out learning butterflies, keep in mind that a single butterfly species can vary in size by as much as forty percent, depending upon the nutrients obtained when in the caterpillar stage. The butterfly’s wing pattern is all-important. And even though a butterfly that is several days old will be faded and often worn or torn from an attack by a predator, the pattern can usually be determined.

Fall is a marvelous time of year for many reasons. The hot summer days are behind us, hurricanes are less likely, leaf color begins to change, and butterflies are galore!