A Little Salt in the Thorn Scrub

(A Continuation of “From La Sal Vieja to La Sal Del Rey”)

We drove from La Sal Vieja westward to La Sal Del Rey (“The King’s Salt”), which is another part of the Lower Rio Grande Valley National Wildlife Refuge. La Sal Del Rey refers to a shallow lake sitting on salt deposits, which make it ten times more saline than ocean water. Clint and I visited this place some years ago, on a searingly hot summer day that had us staggering back to the car, desperate for water.


Sign within the refuge



In contrast to the first photo, this one shows that the thorn scrub can be pretty impenetrable.

This mid-October day was far more pleasant. The sky had been clearing, and by now it was a sunny, warm day, with a breeze that kept things comfortable. The first part of our walk took us past mostly open mesquite woodlands with thick grass and huge prickly pear cactus growing in mounds sometimes standing well over head high. Other plants and trees included the ebony blackbead, tepeguaje, and a bush that appeared to be some sort of acacia. This latter plant seemed to be an invertebrate Mecca, attracting all manner of invertebrates. Clint found a pair of stick insects, the female perfectly camouflaged as just another gray branch, and the male more spindly and with green color, as would befit a thinner new shoot off the main branch. There was a large predatory wasp with a red abdomen that never would sit still for a photo and kept flying off, only to return shortly to this apparently irresistible bush. Scattered among the branches were the little ailanthus webworm moths, with folded wings looking like a mosaic of orange and yellow edged in black. There was a mesquite borer, double-banded longhorn beetle, and mantid flies. Snout butterflies fluttered among the branches. And growing fat among this buffet of insects was a green lynx spider that had pounced on some sort of colorful fly which was now being drained like some dipteran Slurpee.


Stick insect, female


Stick insect, male


Green lynx spider with fly

We arrived at the lake and I walked up on the observation deck to see the broad salt flats shading into the lake, with a large group of sandpipers milling around at the water’s edge. It was like a glimpse of the beach in microcosm, only the water was undisturbed by any wave or movement. The birds presumably were poking in the sand for prey. I approached, and at one point they spooked, briefly flying in a tightly coordinated group, quickly returning to the wet sand to continue their activity.


Scrub, then salt flats, and finally the lake




I walked out over the salt-crusted sand and silt toward the water, in places crunching on a glittering deposit of salt. I approached the sandpipers, which shuffled about nervously but did not fly away. Several of their group hopped about on one leg, like little one-legged pirates. My reaction to the first bird that did this was a concern that it had lost a leg and was forced to hobble about with his brethren. Then I saw that it appeared to be a habit among numerous members of this troupe, and I was less concerned.

Walking back from the bare salt flats into scattered vegetation, I wondered what could live in the salty, bare sand, in many places under a brittle glaze of salt. I took a photo of one of the principal plants which appears to be a saltwort, with succulent little fingerlike leaves, pale green or blue-green toward the top but pinkish toward the base.


Silver argiope

Walking back, I spotted a kind of argiope spider sitting in its web constructed in a clump of prickly pear cactus. Clint identified it as a silver argiope, a more southern resident that barely crosses into the United States. It has the basic argiope or garden spider form, but its abdomen has some projections that were fairly subtle in this young one but Clint says become more pronounced in adults.

We did see a couple of whiptail lizards, and the second, tiny one reminded us that this year’s eggs have fairly recently hatched. We saw lizard scat, suggesting that there were many other lizards we did not get a chance to see. But our walk had been a pleasant one filled with invertebrates of amazing form and color, sandpipers, and a pair of magnificent caracaras soaring over the thorn scrub.

Western (Texas) Ratsnake

fullsizeoutput_1011Many years ago I was contacted to go to my son’s day care, which had some land and kept a few animals around a small barn. They said that a big snake had been eating the duck eggs, and the culprit had been spotted earlier in the day. I went over and had a look, and as I raked hay away from what appeared to be an old burrow in the floor of a stall, I caught sight of the dark coils of a ratsnake. After pulling about five feet of Texas ratsnake from her refuge, I then had to get a very unruly snake into the bag so that I could relocate her. A day or two later I took the snake to the wooded corridor of a large creek and tried to pose her for some photos before letting her go. This did not go particularly well; draping a big ratsnake along a log by the woods gives the snake an immediate plan for escape and a very impatient attitude about sticking around for pictures. Of course she turned and bit me. I stood, finger dripping blood into the creek, wondering how many hundred times I have been bitten by Texas ratsnakes. Meanwhile I did get a photo or two before the big snake climbed into the highest branches of a nearby pecan tree.

I wished her luck, and she would need it. Relocated snakes often do not do very well, because they learn to recognize a particular area (their “home range”) where they live, and when taken somewhere new, even if the habitat is pretty good, they may act as though they are lost, and wander without settling down. Many studies of translocated snakes show that they’re more likely to die, failing to avoid hazards and/or to take advantage of resources in the new location. However, sometimes a snake like this Texas ratsnake faces a dilemma: stay and be killed or get relocated and “lost.” At least in her new woodland, she had a chance.

While I stubbornly hang onto the name “Texas ratsnake,” this species was re-named a few years ago after improvements in the scientific understanding of the relationships among North American ratsnakes. Its proper name is now the western ratsnake, Pantherophis obsoletus. What used to be called the “black ratsnake” and “yellow ratsnake,” east of the Allegheny Mountains, is now the “eastern ratsnake,” Pantherophis alleghaniensis. In the middle part of eastern North America, they are Pantherophis spiloides, a new name for the gray ratsnake. West of the Mississippi River, they become western ratsnakes, but some habits are hard to break, and so I still call them Texas ratsnakes.

This species may be the subject of more run-ins with people than any other snake in our area. Lots of “snake calls” are generated by people seeing a Texas ratsnake in their trees or yards. Soon after eggs hatch at the end of summer, babies sometimes turn up in people’s garages and sheds. Lots of them are killed on the road each year. Yet somehow, they continue to be abundant year after year around parks and suburbs (as well as in more remote locations).

This is one of our longest snakes, averaging about 3.5 to 6 feet long, with a record length of seven feet, according to Werler & Dixon’s Texas Snakes: Identification, Distribution, and Natural History. Like several other ratsnake species, the Texas ratsnake’s body, seen in cross-section, is rounded on top and squared at the bottom, like a section of a loaf of bread. This is thought to aid them in climbing trees.

The adult snake’s fairly broad, flat head is dark gray on top, shading to white on the lips and chin. Starting with the neck, there is a pattern of dark saddles going down the back. The dorsal ground color may be yellowish-gray to gray or charcoal. Along the sides is another row of blotches, these being somewhat diamond-shaped. The skin between the scales of the neck and forebody generally includes reddish or orange color, more visible when the skin is stretched. Some of the skin between the scales within the blotches is light gray to white, showing as small flecks of white in a patch on the lower parts of the blotch. Add to this one further complexity of pattern – many adults have the suggestion of vague, smudgy stripes where the edges of the blotches seem to smear a little and join each other down the back. On the belly, the scales are light on the throat, darkening from front to back with large pale squarish blotches and then a mottling of gray and yellow toward the tail.

Texas rat snake - subadult female

A young adult Texas ratsnake with more yellow in the background color


An individual with lots of gray color, though considerable red can be seen between the scales

Hatchling Texas ratsnakes have brighter and bolder patterns than the adults, with a light ground color so that the blotches stand out more. On the top of the head, juveniles have some dark spots and flecks, and a broad, dark band across the snout just in front of the eyes. That band then goes through the eyes diagonally to the jawline. The pattern darkens with age.

E-o-lindh- juv-LBJG-Jun02

Juvenile Texas ratsnake

Texas ratsnakes take advantage of a wide variety of habitats within roughly the eastern two-thirds of Texas where they are found. They occur in east Texas and down the Gulf Coast to Corpus Christi, and in central Texas to a little west of Wichita Falls, out to San Angelo, and southwest nearly to Del Rio. This means that they live in east Texas piney woods, bottomland hardwoods, cross timbers woodland, and savannas from north Texas down through the Hill Country. They are excellent climbers, and this may be one factor in their success, keeping them away from ground-based predators and people at least some of the time. While up in the trees, they may eat birds and their eggs.

My field notes and my memory indicate that I’ve found lots of Texas ratsnakes in patches of prairie, old fields with at least a creek nearby, and woodlands and forests. During the day, I have been more likely to find them by flipping cover such as discarded plywood or logs. I’ve seen a great many on back roads at twilight or at night, quite often in brushy or wooded areas, or within a short distance of a creek. Undoubtedly they use wooded creek and river corridors to move around in more dry, open areas further west in their range.

Both the accepted common name, “rat” snake, and the often used name “chicken” snake refer to some of their preferred food. A stomach contents study cited in Werler & Dixon, looking at 100 wild specimens in north Louisiana, found mice, rats, and a few squirrels and rabbits in their stomachs. This snake is more than happy to eat birds and their eggs. Coming upon nests, it may eat eggs or fledglings. A big adult reportedly can swallow an adult chicken. While this may not make the Texas ratsnake popular with either farmers or birders, it is simply doing its “job” and may eat enough rats that it does the farmer more good than harm.

The most memorable activity seen in Texas ratsnakes may be their belligerent self-defense when cornered or handled. When first approached, the snake may “make a break for it” or may stay where it is. I have often seen one pull its body into a series of short kinks and sit still, hoping that it won’t be seen. Once picked up, the snake thrashes in an attempt to get away, and may bite repeatedly while discharging musk from the other end. While some snake musk is only moderately disagreeable, musk from a Texas ratsnake is very offensive, a little reminiscent of burnt tires. But the open-mouthed gape while looking for an opportunity to bite is worse. Very commonly, having picked up one of these snakes, it remains coiled on one of your arms as if it were a tree limb while gaping at your hand or other arm as the obvious visible target. If your hand moves closer, the snake will strike, leaving a series of pinprick holes. Occasionally it will hold on and chew. It is important to remember that this only happens to humans who harass and pick up a ratsnake; an observer who simply watches and photographs will not be attacked.


The famous Texas ratsnake gape, ready to bite the attacker

One additional note in defense of the Texas ratsnake, showing that biting is only self-protective and never because it wants to pick a fight: I have many times been able to pick up a Texas ratsnake by slipping a hand under it and supporting it while giving it no target that looks like an enemy. A freshly-caught ratsnake may crawl from one arm to the other as long as nothing comes at it like an attacker. However, this is in no way foolproof, and fairly often it pauses and seems to recognize that this is no tree, abruptly biting my arm. And again I would stress that I have never, ever been bitten by a Texas rat snake that I was  not handling or attempting to handle. They have no venom and they have no interest in becoming aggressive as long as they are left alone.

Spring mating results in the laying of a clutch of five to twenty eggs in June or July. The eggs are laid in rotting logs, in a protected area under leaf litter, in abandoned mammal burrows, or under rocks. It is also known to use above-ground tree cavities for nesting, and the description in Werler & Dixon notes that the tree cavity was used by perhaps four different females for communal nesting. The eggs hatch in August and September, and the baby snakes have much the same temperament as their parents!

(This article is adapted from one I wrote for the January, 2003 issue of the Cross Timbers Herpetologist, newsletter of the DFW Herpetological Society.)

Hanging Out With Master Naturalists

Texas’ wildlife and wild places can use all the friends they can get. Many of our citizens are in the grip of “nature deficit disorder,” and so the best friends nature can have are those who like science and natural history. Luckily, there is a cadre of people who study nature in Texas, who like nothing better than spending time immersed in it, and volunteer to support it. Who are these ecological illuminati? They are Texas Master Naturalists, an organization with 42 chapters in Texas and over 8,000 trained volunteers. Last Tuesday I spent the better part of three hours with the incoming group of Cross Timbers Master Naturalists, teaching their herpetology class. We followed up yesterday with a brief walk at the edge of the marsh and in the bottomland forest at Fort Worth Nature Center & Refuge.

We started at the marsh boardwalk, expecting to find a few frogs and a basking turtle or two. Sure enough, I quickly spotted a green treefrog on a reed stalk. Adhering to the stalk like a lime-green lump, it stayed motionless as the group of us pointed, took photos, and talked about this beautiful little amphibian. I encouraged the group to take any opportunity they could get to listen to a springtime breeding chorus of these frogs at night. Hundreds of eagerly “quacking” male green treefrogs at close range in the darkness is a slightly overwhelming and oddly beautiful experience.


A green treefrog at the boardwalk, FW Nature Center & Refuge

We also spotted a couple of young American bullfrogs, sitting on the mud beside the water and so marvelously matching the color of mud and algae that they were hard to spot without looking for the outline of the body and the two eyes scanning the area for insects to eat and for any approaching watersnake or heron with a taste for bullfrog. While adult bullfrogs may reach up to eight inches in snout-vent length (that is, not counting the legs), these may have emerged from tadpole stage earlier this year. Some were only a couple of inches in snout-vent length.


American bullfrog (photo taken at LBJ Grasslands, Wise Co.)

The second group was treated to a glimpse of a western coachwhip as we left the boardwalk area. It took off within a small group of trees and greenbriar and I followed as quickly as possible, but these snakes are fast and agile as they thread their way through downed branches and greenbriar tangles. We lost it where a small log lay in the leaf litter, and did not see it again although I had people position themselves around the perimeter (watching for a “back door” escape), I used the snake hook to move the log, and we scanned the branches of surrounding trees. Perhaps it had already slipped away before we could get in position, or maybe a cavity where roots had rotted away provided it a deeper refuge. I love these slender, four or five foot harmless snakes. They are among the fastest and most agile of Texas snakes, and they have big, bright eyes and a tendency to “periscope” up to look around in curiosity.


Bottomlands, Fort Worth Nature Center & Refuge

We then walked into the bottomlands near the marsh. Here was a chance to see cottonmouths, watersnakes, frogs and toads, skinks, and other herps. Not that I expected we would hit the jackpot and see all these things, but we had a great chance to see some of them. Every herp trip is a roll of the dice, and in a big patch of habitat you can only turn a few of the logs and examine a small sample of leaf litter and tree trunks. Every additional hour and each new acre of habitat increases your odds of finding things. As it was, we saw a series of toads ranging from a tiny toadlet to a small adult Gulf Coast toad. We talked about the difficulty of identifying toadlets, while every millimeter of additional growth makes a pattern a little more apparent, cranial crests a bit more visible, and the shape of parotoid glands more apparent.

Someone in the first group noticed a little wiggle in the leaf litter, and that wiggle belonged to our smallest skink, the “little brown skink” (an unimaginative but accurate name). These two-toned brown to slightly coppery-colored lizards have small legs, long bodies, and almost seem to swim through decaying leaves and soil. I will never forget its description, in the Conant & Collins field guide, as an “elfin reptile of the woodland floor.” It took me several tries, using care not to break the tail of this subadult skink, before I had it in hand for closer inspection by the other participants.


Little brown skink

Elsewhere in the bottomlands, there were many invertebrate treasures to find. Someone found a luna moth that had finished its short adult life and fallen to the ground. Luna moths are always a beautiful and special treat with their pale green wings, the hindwings gracefully trailing behind in an adaptation that I understand is designed to fool bat radar. And spiders had spun webs between branches everywhere. Especially common were the spiny orb weavers, little spiders with flattened abdomens and spines projecting around the edges (in the larger female spider). Sitting in the center of their orb-shaped webs, the spider can look like a small thorny seed that has become stuck in the web.


Spiny orb weaver

I try to navigate through places like this with some care not to run into the webs. As a child, I had put my hand down a small burrow in the back yard and brought up a tarantula, and the experience was badly frightening. I had a severe spider phobia for some time, but in later childhood when I hung out with biologists at the Fort Worth Children’s Museum it became apparent that in order to pursue field biology, I would have to tolerate a certain closeness with spiders. The field trips were a sort of “exposure therapy,” which is actually the most effective treatment for phobia, and I came to have a certain appreciation for these arachnids – but I stop short of handling them and certainly don’t want to become entangled in their webs! When this happened a couple of times during our walk, I managed not to squeal like my former eight-year-old phobic self, but it sure was not the high point of the outing.

We were careful not to indiscriminately damage rotting logs, but those we rolled over or examined often contained bess beetles. I took a photo of one that was reddish-brown rather than black, and texted it to Clint, who identified it as a just-metamorphosed bess beetle whose chitin would soon harden and turn black. BugGuide says that these beetles live in family groups in galleries within the rotted logs that they eat. Adults take care of the larvae and feed them pre-chewed wood.


Bess beetle

It seems like the ideal herp trip is one in which there are folks who know about and can interpret many aspects of the natural world, even if you aren’t finding a whole lot of herps. This little trip was enjoyable both for the herps we found as well as for the fascinating invertebrates, the giant cottonwoods, and all the other life of the bottomland forest. “Thank you” to the incoming Cross Timbers Master Naturalists, for making this a shared learning opportunity!

Conant, R., & Collins, J.T. (1998) A field guide to reptiles and amphibians, eastern North American (3rd Edition). NY: Houghton-Mifflin.

Night Driving on the Rolling Plains

Out in the red dirt country, the grasslands with mesquite and prickly pear, we have seen lots of wonderful things. Clint knows this country better than I, but I have walked and driven on the part of the Rolling Plains roughly between Abilene, Wichita Falls, and Lubbock enough to love the openness, the raw and uncompromising extremes, and the wildlife in this part of Texas. There’s hardly a better place to listen to the song of the coyote, catch a glimpse of owls at nightfall, and of course to see rattlesnakes, coachwhips, long-nosed snakes, and the Texas horned lizard.

Yesterday we set out again to drive out there, Clint with his legs healing from a terrible accident at work and just now able to tolerate longer drives without elevating his feet, getting around on crutches like a pro. We chased a few rainstorms westward, getting positioned so that we would be west of Graham by sunset and ready for what we hoped would be some snakes on the move, crossing the roads. Seeing snakes is wonderful, but we both love the land, the trees and flowers, the bugs, birds, and furry things enough that we are pretty easy to please. As long as the landscape is mostly intact, only lightly altered by the hand of man, we will find things to admire and wonder about, whether reptilian or otherwise.

Past Jacksboro, Clint spotted a coyote out loping along, paying no heed to the nearby highway or to the risk posed by his being out there in the light of day for all to see. Many decades ago, I helped take care of a coyote at the Fort Worth Children’s Museum, and feel some sadness even now for the close confinement of that irritable old codger, a big old boy that paced his cage and never had the social connection and chance to roam that these animals need. When they live on ranchland, landowners might consider them pests, but much of their diet consists of rodents, fruit when it can be found, and occasional carrion. Coyotes have been amazingly resilient in and around cities. Our former governor famously shot one while out walking his dog, and some of us might have rooted for the coyote instead. They certainly could be threats to smaller dogs, but overall, coyotes are smart, elusive predators with whom we can usually coexist.

The sun was setting in shades of brilliant tangerine, and we looked for a place to take a photo. I hoped for some place where I could look out toward the horizon with no towers, storage tanks, or telephone lines in the way. We just about gave up on finding such a spot before finding a good enough location where nothing but trees were on the horizon, and the sky was golden and then shaded past orange clouds to a deepening gray-blue sky and a crescent moon overhead.


August sunset on the Rolling Plains

We were not alone in greeting the sunset. Somewhere nearby we heard the lonely, whistling call of a chuck will’s widow. Soon this “night hawk” would be flying, catching insects and settling in some spot on the ground, maybe in the gravel off the shoulder of this highway. A little further down the road, we spotted a great horned owl sitting on a telephone line, no doubt scanning the ground for movement. A scurrying wood rat, a cottontail rabbit crouching among the grasses, or even a skunk prowling around may be preyed upon by this big owl. Its wingspan can approach 50 inches (around four feet!) and the force of a strike with those big talons is enough to break the spine or crush the skull of many prey animals.


Great horned owl

Somewhere before Haskell we turned around and headed back. Although the temperatures were holding within the 70s, it was just not a night for significant snake movement. We did see the ghostly image of another coyote, at the edge of the reach of our headlights, trotting across the road. Then, we passed a big owl standing in the opposite lane. Perhaps it had just dropped down to claim some rodent that had ventured out on the pavement. The most amazing sight was a badger, who abruptly came into view near the center stripe of the road, apparently feasting on some road kill. In our brief glimpse, the big mustelid jumped back a little and looked as if to say, “hey, watch what yer doing!” They don’t yield an inch, even to a speeding car.

It reminded me of a day trip Clint and I took in July of 2014, driving back roads in the vicinity of Aspermont. At nightfall, we came upon a badger who was beginning to dig in an embankment. Finding himself somewhat trapped between the car and the steep wall of red dirt, he turned and faced us with a growl that was enough to make anything, animal or human, a little weak in the knee. I got a photo from within the car, but Clint was standing behind the car and trying for an even better shot. I called out something about being extremely careful; these guys are not related to wolverines for nothing! The encounter ended with no injuries – Clint got his shot and got back in the car, and we let the badger go on his way. (I don’t think we “let” the badger do anything; he decided what to do and did it. David Schmidly mentions a documented report in which one badger held off two coyotes, and I’m pretty sure this one could have kicked our butts all the way back to the metroplex.)

Stonewall Co., TX, NW of Swenson

Badger, Stonewall County

There were plenty of other joys on that trip to Aspermont in 2014, like the numerous roadrunners sprinting ahead of us or taking low, short flights to a nearby tree branch, or the coachwhip we surprised on the road. In several places, the road was bordered by a tall plant with beautiful white flowers, each with a flat ring of petals topped with a cluster of filaments. Hovering and flitting among these flowers were sphinx moths. I set the shutter speed to try to freeze the motion of their hummingbird-like wings, to capture something of their brown, pink and white striped and banded bodies.

Stonewall Co., TX, NW of Swenson

Sphinx moth

On that day, we had seen about a dozen Texas horned lizards. Watching the red dirt road carefully, we would see what looked like a chunk of that dirt run ahead a few feet and stop. We would then pull over, jump out, and take some photos of these spiny little dust-pancakes with their two dark-brown horns and alert little black eyes. Close examination of their pattern shows many of the colors we admire in fall leaves. Brown spots are surrounded by a corona of golden yellow, fading into a sandy color that can be nearly orange. This is especially the case for areas with colorful soils, as a population of Texas horned lizards will come to resemble the color tones of their surroundings, giving them a survival advantage because they blend in with the background of soil, sand, and rocks.  For those “of a certain age,” seeing horned lizards is immediately followed by the wistful recollection, “I remember when we could find those in our back yards.” And I do fondly remember those days.

Stonewall Co., TX, NW of Swenson

Texas horned lizard

But on this day, August 26, 2017, we saw no horned lizards in the remaining light before sunset. Nor did we see snakes, until nearly 9:30pm as we were driving back. On the outskirts of Throckmorton, along the shoulder, we spotted a roughly two-foot long serpent, almost surely a rattlesnake. As we pulled over, sure enough it was a young western diamond-back. Out on the Rolling Plains, these snakes are so common that we’ve been known to slow down, note what it is, and drive on. However, when it is the first snake of the night, you stop for a closer look. I took a quick iPhone photo in the glare of the flashlight, and then moved it on across the road in the direction it had been heading. Although the occasional cranky individual will pull back and even strike repeatedly when touched with the snake hook, this one had the more typical laid-back temperament of many western diamond-backs. It tried to crawl away, not frantically but as if getting away from some inconvenience, and never rattled or showed any sign of annoyance. And with that, Clint and I could claim that we had not actually gotten “skunked.” It was our only snake of the night, but how could we possibly complain about a night seeing owls, coyotes, a badger, a frog and toad or two, and one easygoing little rattler?


Young western diamond-backed rattlesnake, near Throckmorton, TX

Manaster, J. 1997. Horned lizards. Austin: University of Texas Press.

Schmidly, David. 2004. The mammals of Texas, Revised Ed. Austin: University of Texas Press.

Smith, D.W. 2002. Wild bird guides: Great horned owl. Mechanicsburg, PA: Stackpole Books.



(And the Things-On-The-Snow-On-The-Prairie)

One of the best things about an August visit to a prairie may be getting to see snow-on-the-prairie. “What?” you may say, “It was 100 degrees today, and the heat index was 105. Good luck seeing snow.” But this is a special sort of snow, a plant in the spurge family whose simple white flowers are surrounded by floral leaves with white edges. At first glance you would think that those leaves are the flower, but as you look closer you see the little flowers with five petals at the center of these groups of leaves.


Snow-On-The Prairie

I first saw this beautiful plant at Parkhill Prairie, a prairie remnant east of McKinney that is part of the blackland prairie. I then learned that it is found in places throughout the eastern half of Texas and beyond. I figured that the prairie at Tandy Hills Natural Area in east Fort Worth would be another good place to see it, so I visited there today, despite the heat.

And it was hot! I walked the trails for a while, found shade under a juniper and sat for a while, and then walked some more. The little bluestem (maybe this region’s most noteworthy native grass) was healthy blue-green and all the plants appear to have benefitted by the unusual August rains this month.


Little bluestem in the foreground

Like most prairie within the cross timbers, there are patches of open grassland bounded by clusters of trees or wooded ravines; there are no huge expanses of grass. As I climbed a small incline between patches of trees, I nearly bumped into a common prairie resident that thrives in late summer – a golden argiope or garden spider. She had woven her web between two clumps of bluestem, and this had pulled them toward each other to form an arch. She sat in the middle of the orb-shaped web, waiting for some insect to wander into that sticky web. With my apologies for nearly ruining her web, I took a photo of her underside and then walked around to get a photo of her upper body.IMG_2292


A golden argiope, underside shown in the top photo and upper body in the bottom photo

Walking further, I found a couple of snails stuck to vegetation, and I wondered what it must be like to be stuck to something, waiting out the day in full sunlight in a Texas summer. I needed to take advantage of the dappled shade every few minutes, and I’m amazed that some of these creatures tolerate the heat so well.


A snail stuck to prairie grasses

I found my way into more patches of snow-on-the-prairie, and promptly saw a spider on one of them. It seemed amusing to consider “things-on-snow-on-the-prairie,” and I began to look for more. I saw a honeybee, a large wasp, and then came across a large fly with a green abdomen. When I sent him the photo, Clint said it was one of the species of soldier fly.


Soldier fly on snow-on-the-prairie

In short order I came upon a wasp on the snow-on-the-prairie, and approached it closely but only managed a rather fuzzy photo. I’ve learned that I can approach bees and wasps without much worry if I don’t make sudden close movements or get too close. This particular one was a pretty brown and yellow wasp that most people call a yellow jacket, but it is more properly called a paper wasp, after the paper nests that they build, suspended from branches, ledges, and the eaves of houses. Real yellow jackets live in burrows in the ground. Clint identified this particular one as Polistes exclamans, a name that always makes me smile as I picture someone “exclaiming” after being stung.


Paper wasp, Polistes exclamans

Another treat during this walk on the prairie was the eryngo, or Leavenworth’s eryngium. It forms beautiful purple spiny flower heads with a stiff row of spines below and a small “crown” of spines above. People often think of it as a thistle, but it is not a true thistle.


Leavenworth’s eryngo, or Leavenworth’s eryngium

By this time I had nearly forgotten the oppressive heat. Standing in a field with eryngo, Maximillian’s sunflower, and snow-on-the-prairie, the heat seemed irrelevant. Soon however, it was time to leave, but I hope to return soon to this little gem of a preserve, managed by the folks from Fort Worth Nature Center & Refuge, and loved and looked after by the Friends of Tandy Hills Natural Area.


Bumbling Around the Partridge Pea

I needed to get out, regardless of the steamy pattern of rain and heat this weekend, and so I headed to the Southwest Nature Preserve for a short walk. Somewhere along the sidewalk there was a large patch of what I’m reasonably sure is partridge pea (and if I’m wrong I trust my fellow naturalists will correct me), its yellow flowers being visited by an assortment of honeybees, bumblebees, wasps, and butterflies. I decided to take a few photos and brief video of the American bumblebee doing its thing. These big furry bees don’t seem bothered when approached, though I suppose if you stumbled into one or swatted at it, things could get a little tense.


South end of a northbound bumblebee

It was a great, though brief, escape from a nightmarish weekend for our country. All this hymenopteran buzzing and busy-ness was soothing in its shifting patterns of yellow, black, and green.

One of these American bumblebees devoted quite a bit of energy to what appeared to be scraping pollen onto the large mounds already collected on its back legs. At one point she appeared to be hanging from the flower by one leg as she scraped and scraped.

It is amazing to watch these bumblebees in flight, as they hover and drop slowly into tangled branches and flowers, then take off and maneuver easily around the stems and leaves. (Well, it looks easy to me; they do bump into stuff at times!)

The bumblebees also took advantage of the Maximilian sunflower blooming all around the walkway. And not just bumblebees – I got a workable iPhone photo of a small bee that Clint thought might be a leafcutter bee.


Might this be a leafcutter bee (genus Megachile)?

It was a nice visit – I’m never disappointed when I visit this preserve!fullsizeoutput_fda


A Summer Sunset at That Pond

In January of this year, I sat for an hour at the edge of a pond at Southwest Nature Preserve and then wrote about what I saw. I sat there again in March, taking note of the changes as spring progressed. On July 21st, it was time to do it again, but I went with some misgivings. There had been heat advisories during recent days, with the humidity making the heat index very uncomfortable. I took plenty of water!

IMG_1171It was a great day for Orthopterans and Odonates. The grasshoppers scattered out of the dry grass in front of me as I walked to the pond, and then when I arrived the dragonflies hovered and flitted around the water’s surface. Pondhawks settled on twigs and stems at the pond’s edge, and skimmers floated on the air, then quickly darted to the water’s surface. Whoever gives names to these Odonates seems to have more of a descriptive or whimsical sense than do herpetologists. We give names like “plain-bellied watersnake” or “Texas brownsnake,” while they use words like “blue-eyed darner,” “red saddlebags,” or “Halloween pennant,” invoking a sort of poetic sense with names that describe these fantastic insects.

I settled in beside the black willow where I have sat in each of these visits, putting out a small thermometer that soon reached 90 degrees in the shade of the willow, a big improvement from the high of 100. Periodically, a light breeze stirred things. The pond had grown a huge crop of some submerged plant that might be sago pondweed or maybe southern naiad, thin strands with filamentous leaves forming big clumps or mats. It brushed the surface of the water all around, from the edge toward the center, leaving a circular area in the center of the pond where none of it was evident. In that central area, two or perhaps three pond turtles’ heads surfaced, they paddled along briefly, and then submerged. One day I will learn to keep binoculars in the pack; if I had brought them, I might have been able to identify the turtles, which were almost surely red-eared sliders.

What would a hot summer evening be without the calls of cricket frogs? One of them soon began to call from somewhere to my right along the pond’s edge, with that gradually accelerating “grick-grick-grick” cutting through the hazy summer air. On my walk around part of the water’s edge, there were many of them hopping into the water or back into the surrounding vegetation. I did not see bullfrogs or leopard frogs, just dozens of little cricket frogs.

As the light began to fade, swallows began to appear, gracefully flying over the pond and engaging in all sorts of acrobatic maneuvers as they chased insects. I would imagine that they were barn swallows, but again, where were those binoculars? In any case, it was a quiet and peaceful few minutes there at the close of the day, with the sun sinking below the horizon and the dark silhouettes of the swallows cutting across a dimming pastel sky.


Just before dark. The central part of the pond that was free of vegetation is visible here.

A Giant Serpent of the Prairies? A Bull That’s No Bull!

A few years ago, driving along a back road in Parker County, a long, uneven dark line came into view on the pale caliche road. I pulled up closer on a four-foot snake stretched out in its sunset wanderings, nervously eyeing the human that was walking up to it. The bullsnake flattened its neck and tongue-flicked to check whatever scent it could pick up in the air, but tolerated my approach. There was a big scar along the right side of its face, probably the result of a near-fatal encounter with a predator or maybe a human. For a few moments it warily put up with my crouching beside it and I admired its allowing me to be there despite the glowering, don’t-tread-on-me expression on its face. And then, it was time for it to move on into the grasses and wildflowers, making its way along to wherever it was going. This was a treasured encounter in which the snake made no panicked attempt at escape or big defensive display, and I sought only to share a moment with the snake, without trying to collect it or harm it. I could almost make the case for it being marked by mutual respect, though the bullsnake probably just regarded it as a near-miss with something that could hurt it.

The bullsnake is one of our largest nonvenomous snakes, routinely growing to four or five feet in length. The record length is nearly nine feet long (Werler & Dixon, 2000). It is not so slender as a coachwhip, but smaller in girth than the western diamond-backed rattlesnake. The bullsnake has a pattern of dark blotches on a lighter sandy or tan background, with the darker blotches becoming more ring-like toward the tail. Its head is not as flat as is the case with other larger snakes such as the ratsnakes, and the snout is vertically flattened a little. At the tip of the snout, the rostral scale is taller than it is wide, and is somewhat raised from the surrounding scales. The structure of the underlying skull is more rigid than that of most snakes. Taken together, the head shape and skull rigidity enable the bullsnake to be very skilled at digging and excavating.


Bullsnake head, showing the vertically flattened snout and slightly raised rostral scale


A young bullsnake, from Parker County

The bullsnake’s skills as an excavator were described by Carpenter (1982), who tested eight bullsnakes in an enclosure with sand substrate. The snakes generally began prodding the sand next to a stable object, and began digging sand with sideways movements of the head. Then, the snake bent its head to the side to scoop loosened sand and move it away. A loop of the neck continued to push the sand backward. In further testing, bullsnakes were seen to excavate tunnels up to a meter long. Additionally, Carpenter examined whether bullsnakes would recognize pocket gopher mounds, and showed that these snakes actively explore and excavate pocket gopher burrows in attempt to eat the gophers.

The diet of the bullsnake includes various rodent species, birds and their eggs, and the occasional lizard. Werler & Dixon (2000) reviewed literature suggesting that they may eat burrowing rodents such as gophers in greater numbers than species such as the hispid cotton rat that spend more time above ground.  Rodriguez-Robles (1998) examined published reports of stomach contents of Pituophis catenifer (including gophersnakes and bullsnakes), finding that mammals constituted 77% of prey items.

Their range in Texas includes central and west Texas with an eastern boundary that includes Lamar, Henderson, McClennan, Bastrop, and Victoria Counties (Dixon, 2013). That is, the eastern boundary of their range runs a little east of a line from Dallas down through Waco, Austin, and Corpus Christi. This means that the blackland prairie and parts of the adjacent post oak savannah serve as the eastern boundary of the bullsnake’s Texas range.  In west Texas, the bullsnake shades into the Sonoran gophersnake subspecies around the Pecos River. Bullsnakes occupy niches within the south Texas plains, the hill country, the cross timbers, rolling plains, and high plains. They make use of open habitats such as prairies and plains, but can also be found in rocky hillsides and bluffs in the hill country. A study of bullsnakes in Wisconsin found that the snakes preferred south-facing open canopy bluffs but mostly avoided agricultural lands (Kapfer, et al., 2008). They examined the relationship between amount of preferred habitat and home range size, and concluded that where there are large patches of good habitat, bullsnakes can live within smaller home ranges. Where preferred habitat (such as grassland and savannah) is broken up by farmland and other less-usable land, they travel over larger areas and do not survive as well. Werler & Dixon (2000) noted that researchers in Nebraska reported bullsnake home range sizes of 10 to 42.5 acres.

Predators of bullsnakes undoubtedly include birds of prey such as the red-tailed hawk, as well as coyotes and other medium-sized carnivores. It seems very likely that people are a significant source of bullsnake mortality. Because they are large snakes that are sometimes active during the day and frequently cross roads, they are more easily seen and targeted by humans who may kill them or run over them in cars. Additionally, the slight resemblance of bullsnakes to rattlesnakes undoubtedly increases the number of deaths at the hands of humans. Bullsnakes have a very intimidating threat display when cornered or caught, raising the head and first part of the body in preparation for striking, hissing loudly, and vibrating the tail. The hissing has been described as like the sound of escaping steam, and it shares a little similarity to the high-pitched buzz of an enraged rattlesnake. The particular sound quality is the result of a small band of tissue (the epiglottis) positioned vertically just at the opening of the airway (the glottis). When air is forced around it, a loud hissing sound is created. A large bullsnake that is aroused in such a way gives the impression that it could be quite dangerous, although it is not. Instead of frightening the person away, it’s likely that this behavior often leads to the snake being killed.


The glottis is the opening just behind the tongue, and the epiglottis is the vertical strip of tissue just in front of it

Many of us, at least in north central Texas, would report seeing fewer bullsnakes than we used to. Decades ago, I remember finding them much more often, but the cities were smaller then and there was more prairie and ranchland around the edges of Fort Worth. However, bullsnakes are not considered to be imperiled overall. The International Union for the Conservation of Nature (IUCN) notes that the bullsnake has not yet been assessed for the Red List of Threatened Species. It is not listed in the Species of Greatest Conservation Need compiled by Texas Parks & Wildlife Department. Overall, the status of the bullsnake in Texas has not been identified as a concern, but like many other species of herpetofauna, we may not know just how secure it is. I hope that bullsnakes continue to live in healthy populations wherever there is enough good prairie and savannah habitat. When I think of the prairie out west of Fort Worth, the image of the bullsnake comes to mind along with images of grasses and forbs, pale yellow yucca blooms, little massasauga rattlesnakes, and the beautiful calls of doves and chuck-will’s-widows in the evenings. It is a wonderful, shrinking ecosystem, and I hope we save it in places here and there. And it would not be the same without the bullsnake.

Carpenter, C.C. 1982. The bullsnake as an excavator. Journal of Herpetology, 16(4), Pp. 394-401.

Dixon, J.R. 2013. Amphibians and Reptiles of Texas (3rd Ed.) College Station: Texas A&M University Press.

IUCN Red List of Threatened Species (Internet). http://www.iucnredlist.org/search (accessed 2/12/17)

Kapfer, J.M., J.R. Coggins and R. Hay. 2008. Spatial ecology and habitat selection of bullsnakes (Pituophis catenifer sayi) at the northern periphery of their geographic range. Copeia 2008(4), Pp. 815-826.

Rodriguez-Robles, J.A. 1998. Alternative perspectives on the diet of gopher snakes (Pituophis catenifer, Colubridae): Literature records versus stomach contents of wild and museum specimens. Copeia, 1998(2), Pp. 463-466.

Texas Parks & Wildlife Department. Texas Conservation Action Plan: Species of Greatest Conservation Need.  http://tpwd.texas.gov/landwater/land/tcap/sgcn.phtml  (accessed 2/12/17)

Werler, J.E., and J.R. Dixon. 2000. Texas Snakes: Identification, Distribution, and Natural History. Austin: University of Texas Press.

The Woods at Ray Roberts Lake State Park

It was time to search for more areas within the eastern cross timbers, which are blackjack and post oak woodlands dotted with small “pocket” prairies and meadows. Clint and I both want to get to know the woodlands and prairies of north Texas more completely. We both grew up here, but it is surprising how you can get to know some areas so that they become familiar friends while completely missing other places.

crosstimbers map

Portion of a map showing the eastern cross timbers (29b) and western cross timbers (29c). Map citation:  Griffith, G.E., S.A. Bryce, J.M. Omernik, J.A. Comstock, A.C. Rogers, B. Harrison, S.L. Hatch, and D. Bezanson, 2004, Ecoregions of Texas, U.S. Environmental Protection Agency, Corvallis, OR.

In north-central Texas, two belts of oak-dominated woodland extend down from the Red River, ending just above Waco in the east (the eastern cross timbers) and around the Colorado River in the west (the western cross timbers). The eastern cross timbers is skinnier and smaller, and running underneath it is Woodbine sandstone, which makes for reddish sandy soil. The patch of eastern cross timbers that I know best, at Southwest Nature Preserve in Arlington, has outcrops of iron-rich sandstone along with smaller rocks on the surface of the sandy soil. As the years progress, more of these woodlands disappear under the bulldozer in the metroplex and all up and down the I-35 corridor. But looking at a map and the Texas Parks & Wildlife Department website, it seemed that the “Isle du Bois” unit of Ray Roberts Lake State Park would contain a good remnant of eastern cross timbers.

Lake Ray Roberts is a little bit northeast of Denton, and along the eastern shore of the lake there is a knob of park land that juts out into the lake. This is the Isle du Bois unit. We decided to meet there, and circumstances dictated that it would be in the middle of a pretty hot day. I got there about noon and began walking from a spot near the Quail Run campsites.


Two juvenile red-eared sliders

Early in the walk, an interpretive sign pointed back to an ephemeral pond partly hidden within the trees. I looked around the margins, expecting that I might find a watersnake, and I did see a couple of baby red-eared sliders that probably hatched last year. I always love seeing wetlands, but my goal was further upland. Soon I was seeing open patches of prairie grasses surrounded by oak woodland. I heard from Clint and his family, and they joined me soon afterward.


small prairie or meadow within the Isle du Bois unit

A good part of our walk was on a “sidewalk” that winds up through the woodlands and glades, but eventually we found a small dirt trail to follow further back into the oak forest. Sure enough, the occasional sandstone broke through the grasses in woodland glades, and much of the soil was red sand. Blackjack oak was everywhere, and it was easy to imagine this being a continuous, unbroken ecosystem extending down to the Southwest Nature Preserve in Arlington.




Three views of the cross timbers woodland

This walk was a good introduction to a place we want to return to and get to know better.

The Big Bend Country as a Refuge for the Soul

This summer, I plan another trip to the deserts and mountains west of the Pecos River. If it was anywhere else, I might have had enough of it by now, but it looks like I’ll never get enough of the Big Bend country. Cool mountain meadows and bright expanses of rocky desert haunt my imagination. I need time “out west” on a regular basis.


In the Chisos Mountains, a view from the Lost Mine Trail

Those of us for whom nature is like an essential nutrient (as Richard Louv puts it, “Vitamin N”) spend time seeking out places to roam like starving people searching for a scrap of food. Urban nature refuges are wonderful, but often have unavoidable noise from highways and airplanes, and everything from discarded beer cans to fast food wrappers. These nature centers are essential and beloved oases in a sea of sprawl, despite the reminders of their urban surroundings. In fact, they are particularly loved and needed because of their urban surroundings.

Outside of these preserves, life is paved. We get from place to place on roaring highways or in glacial traffic jams. We commute from crowded hives buzzing in towering glass buildings, past urban blight and Wal Mart, to rows of boxy houses. Do we want to be constantly surrounded by our stuff? Everywhere we turn, confronted with mirrors reflecting us, our things, what we have done? Being so immersed in ourselves, our products, our excretia, we are distracted from the fact that we are part of nature. We live as if we were the beginning and the end of all things. We are not.

Out in the Big Bend country, much of our self-focused distraction is stripped away. The sky stretches away, limitless and quiet. Ancient mountain ranges are reminders of beginnings long before the earliest human memory. Life depends on rainfall, and on the aquifers flowing beneath the desert. Water, soil (however thin and rocky), green plants, and the bright, burning, radiant sun – these things support life in the Chihuahuan Desert. Wandering among the mountains, grasslands, and desert even for a short time reveals a rich diversity of life that has found ingenious ways of living in places we would consider harsh. It is reassuring that even the arid, sun-baked rocky arroyos of the desert floor provide opportunities for life to thrive. The earth is good and generous in every corner; even this place is a garden.


Chihuahuan Desert, within Big Bend National Park

For many of us, this garden – the Big Bend – is a refuge for the soul. It is one of the rare places where we can walk in real solitude. Stepping out of the overly human-centered world feels to many of us like a healthier perspective. People comment about the Big Bend being “bigger than us,” or “not made by us,” as if the scale and wildness of the place puts us in the right perspective, participating in our surroundings but not controlling them, not overwhelming them. It is as if nature is more trustworthy than human schemes and ambitions, and we need its predictability and its resilience in the face of human folly. When talking with others about this place, I have said that I never feel safer anywhere than I do in the Big Bend. How factually true is that statement? There are no guarantees of safety in the Chihuahuan Desert. An unprepared visitor could become dehydrated and overheated, could fall off a mountain, or could have some sort of emergency and be too far away from help to get through it. My internal feeling of safety comes from the sense of peace, beauty, and trustworthiness of the desert and mountains.

Not surprisingly, those of us who love the Big Bend feel protective of it, and the news that it is under assault by the petroleum industry is very troubling. If those for whom the Big Bend is nothing but a business opportunity get their way, how much of this place will become nothing more than an industrial park? Already, the Trans-Pecos Pipeline is a reality, intending to send fracked natural gas to Mexico, for export on to Asia. The first wells are already pumping in the newly-discovered Alpine High oilfield, a large area between the Davis Mountains and Balmorhea that is thought to contain 15 billion barrels of oil and gas. Those wells are not producing as much as expected, but more wells may be coming, with more roads, trucks, fracking pollution, and methane releases.


The Davis Mountains, with no wells or trucks

Will we lose the peace and beauty of the Trans-Pecos region? Will the nighttime desert landscape be lit by wells flaring methane gas, and will travelers have to dodge speeding wastewater trucks roaring down two-lane highways? Will the beautiful springs at Balmorhea be poisoned by toxic fracking water? Will the pipeline scar across the desert ever heal? I have no answers.