Thursday, March 26, 2009

Seduced by a Siren

For the past several weeks, I’ve cheerfully placed my jacket and sweatshirt in the back of my closet several times, confident that the periodic warm spells had finally signified the last gasp of winter. After each of these gleeful episodes, I’ve had to grudgingly retrieve them the next morning after I opened my front door and was predictably greeted by the cold, crisp air. But now, surely, this is the real deal.

When I stick my head out of the window, I can no longer hear upland chorus frogs calling for mates. This winter-breeding amphibian, whose call sounds like a finger running down a plastic comb, is usually the first species to start singing each year, and the first to stop. Instead, last night I heard grey tree frogs and southern toads trilling in the pond near my home. It’s a good time of year.

Undergraduates at Auburn University sometimes conduct independent research projects for credit and for experience. Since my lab is known for studying interesting critters, there are often individuals working with us and looking for help with their projects, particularly when it gets warm and the amphibians and reptiles start to move around. Last week I received an e-mail from a student looking for help catching one of the most elusive animals in the south, the greater siren.

Sirens are a group of salamanders that don’t subscribe to the typical amphibian way of life, instead of laying their eggs in the water and waiting on land until the next breeding season, sirens simply never leave the water at all. They obtain oxygen through the large, feathery gills that emanate from their neck.

Over time, sirens have lost their hindlimbs and are left with only greatly reduced forelimbs, rendering them incapable of meaningful terrestrial movement. It’s no matter to these eel-like creatures as they patrol the watery depths, legs would only slow them down. We know very little about these secretive animals, they spend the majority of their lives in the muck lining the bottom of swamps, ponds, and similar bodies of water. We do know, however, that they are ruthless and effective predators. Sirens can reach lengths of three feet long and at that size there are few other animals in the water that aren’t potential prey.

The Auburn undergraduate was interested in shedding some light on the ecology of this little known organism. By capturing some and bringing them temporarily back to the lab, he hoped to make observations on how efficient they are at absorbing oxygen. The first step (and what I feel is the most fun part) was finding and catching the sirens.

On Friday afternoon we gathered on campus to collect our gear, into the van went numerous nets, crayfish traps, and a large seine. Crayfish traps, although designed for edible crawdads, are effective at capturing a large number of different animals. They have a simple design: plastic-coated wire mesh is molded into a rough pyramid shape; at the base, there are three funnels leading inside. Aquatic animals crawling around the bottom of the pond may find their way through the funnel and become trapped. The seine is even simpler, a ten foot rectangular net with weights on the bottom is stretched between two wooden poles; one person grabs each pole and drags the net (weighted side down) through the water. Animals get swept up in the net as it is brought through the water. After a sweep, the net is brought to land and the contents examined.

The van loaded, we headed down to Henry County, Alabama to search a pond that was the site of a siren study many years ago. On the drive down I envisioned wading through a vast expanse of marshy wilderness, parting reeds as I strolled through the water exploring the pristine swamp. Imagine my surprise as the van pulled to the side of the road alongside a farm pond surrounded by acres of grassland closely cropped by a multitude of cow mouths. This is it? I thought to myself as I surveyed the pond, similar to so many dotting the agricultural landscape of south Georgia and Alabama.

Carefully avoiding any cow patties, I gave the pond a preliminary examination. I noticed there were some tupelo trees along the shore and a few small patches of aquatic vegetation. I decided I would focus on these areas and any other form of structure I could find. I thought that in a relatively uniform pond such as this, any animals would be concentrated there.

In the fading light, we set out our crayfish traps. We’d check them when our evening was over. I grabbed a steel framed dip net and began to work the shoreline, thrusting the net into the water and working it along the bottom for several feet before hoisting it into the air. It didn’t take long before my arms began to tire from lifting the various leaves, sticks and assorted muck that I captured. After each sweep I eagerly and optimistically peered into the depths of my net, half expecting to see a squirming siren within my grasp.

I began having trouble with my headlamp, it seemed to blink out whenever I tried to see what I had captured, making for a frustrating exercise. It’s unfortunate that we weren’t there to catch aquatic beetles and other insect larvae, we could’ve made it an early night due to my great success. Any amphibians, however, effectively evaded me. I was considerably discouraged by the time I heard some excited yelling coming from the bank several hundred yards away.

Curious, I slowly made my way back to our starting point. By the time I had arrived, there was nobody in sight, however, there lay a large red cooler on the bank. The lid was weighted down by a bucket full of water. I couldn’t resist removing the bucket and peering inside the cooler. There, with gills billowing through a couple inches of water, lay a two foot long siren. Thick as a vacuum hose, the amphibian looked relaxed as I excitedly peered at him.

It turned out to be the only one captured that night, he had been nabbed during a sweep of the seine, likely as he hid within a leaf pack. Despite the traps, the seine, the nets, and six enthusiastic searchers, our success was limited. But the confirmed presence of just one siren indicates that there were probably dozens, if not hundreds more within the pond.

Sirens are rarely seen and hard to capture. We know little about the species, but you should consider how many of these huge, unique salamanders live within your neighborhood pond, marsh or lake. You may be surprised.

Tuesday, March 24, 2009

Reptile Van Winkle

I wrote this column last March, still relevant this time of year.

It’s finally starting to warm up around Auburn. On cue, red-winged blackbirds have begun to make their appearance known in area wetlands. You’ve probably heard them too, singing their distinctive, “Konk-a-ree!” About the size of a sparrow, males can be recognized by their black body and bright red shoulder patch. Small yet fiercely territorial, they’re often found perched on cattails, singing to attract mates and defend their little patch of swamp from other males.

Other animals are starting to appear and look around too. Lizards, snakes, and turtles are all beginning to emerge from the winter refuges to take advantage of the weather to warm their bodies. Most people know that these animals are reptiles and, like all reptiles, they are “cold-blooded”. This term isn’t used so much anymore in scientific circles because it implies that reptiles have no control over their body temperature. It is now known that some reptiles can keep their body temperature higher and more stable than we can, simply through their behavior. This is why you’ll see turtles lined up on a log over the water; they’re trying to raise their body temperature. You may have also seen alligators sitting on a waterbank with their mouth open, this is actually how these animals lower their body temperature. They’re letting heat escape through their mouths. Given how hot a Florida afternoon can be, I don’t blame them for trying.

But a reptile’s dependence on the weather outside brings up an interesting question, one that I hear a lot. If the temperature outside influences the internal temperature of reptiles, how do they last during the cold of winter? It’s a good question because it turns out that different animals have different adaptations for persisting in cold weather.

As you might expect, reptiles hibernate. But if you’re picturing a snake curling up in a cave like a bear might, you may be surprised. These animals don’t hibernate in the traditional sense, they are quite awake.

As cold weather approaches, lizards and snakes start seeking out shelter that will serve as their winter hibernacula (hibernation sites). Common areas include abandoned mammal burrows, gopher tortoise burrows, or the caverns surrounding burnt up tree stumps. In more northern climates, these animals will hibernate together and it’s not unusual to find timber rattlesnakes, rat snakes, and black racers all nestled together in rock outcrops. Down here in Alabama though, these animals tend to be loners.

In their refuges, snakes and lizards wait out the long, cold winter. Impressed? I get hungry just thinking about going just a few hours without food. Their secret is in their slow metabolism. Reptiles can go long periods of time without eating, particularly when it’s cold. As their body temperature decreases, so does their metabolism. Mammals like us need to use a lot of energy to maintain our body temperature, reptiles have no such obligation.

So they lay in their caverns, the cold around them making them sluggish. If these animals were truly hibernating, it would take them a long time to gradually retain their normal activity periods. But this isn’t what we see with snakes. You may have remembered that we received a warm spell over a month ago, during one of the warmer days I stepped outside and found a small red-bellied snake sunning itself on my sidewalk. This is a common, harmless snake in the Auburn area and all are less than a foot long. During warm weather, snakes and lizards may often come to the surface and enjoy the sun’s rays. The small snake that I saw likely crawled back to his shelter that night, before temperatures got too cold again.

Turtles have particularly fascinating strategies for escaping the cold. Most of the aquatic turtles you see will burrow in the mud at the bottom of their pond and swamp and wait for warmer weather there. Now, we’ve already talked about why reptiles don’t need to eat during the winter, but now there’s another problem. How do the turtles breathe?

Since their body is running at such a slow speed, turtles don’t need much oxygen. But holding their breath for months would be a feat not even they could accomplish. Although it may be hard to believe, but turtles are able to absorb oxygen from, for lack of a better term, their butt (technically referred to as a cloaca in reptiles). The chemical processes that turtles undergo during cold temperature are quite interesting and complex.

Swamp Moccasins

This column was originally written in June 2008.

I was sitting in my office a couple weeks ago, commenting to my colleague Sean that I had nothing to do that night, when he offered me the chance to accompany him to Tuskegee National Forest to help him search for cottonmouths.

For his Ph.D. dissertation, Sean is studying how these snakes may influence transmission of certain diseases and it is necessary for him to find snakes in their natural habitat to take blood samples. Unfortunately for me, their natural habitat includes the muddiest, deepest, swamps that Tuskegee has to offer. Oh, and we have to find them at night, when they’re most active.

I agreed to go with him, I thought it would be a good opportunity to get out and see some animals that I wouldn’t otherwise have the chance to observe. I changed into some of the rattiest clothes I owned and before I knew it, we were in the forest, hiking to his research site. You might wonder if I was wearing waders. The answer is no, the swamp terrain is so full of underwater channels (created by beavers) and submerged stumps, that is inevitable that one will fall in, drenching nearly your entire body. This happened to me promptly once we stepped into the wetland.

We mucked around in the water for about 30 minutes and it was quickly dark; I switched on my headlamp and started searching near the shoreline, looking for any snakes that might be hunting in the area, while Sean was in a slightly deeper area. All we had to show for our efforts so far was a brown snake. It wasn’t the species we were after but it was interesting to see this animal in the wild. As it’s not particularly vulnerable to the changes that humans wreak upon the landscape, brown snakes are most often found in people’s backyards.

There were plenty of frogs calling that night though; we could hear many grey treefrogs and bird-voiced treefrogs singing to one another. Although their calls are distinct, they 
are difficult to tell apart by sight. We caught one of the bird-voiced treefrogs and Sean was showing me the difference (the upper legs of the grays are orange or yellow) when he exclaimed, “There is one, a mouth!” Following Sean’s gaze and his headlight’s beam, I noticed only the head of a 
cottonmouth sticking out of the water about 20 feet away, its pale throat caught the light and my attention. In a flurry of activity Sean strode through the water and grasped the snake with his tongs.

So began an elaborate process of handling the snake. The first step is to persuade it into a plastic tube for our safety. Then my job was to hand Sean equipment as needed, including syringes, measuring tape, sample vials, and the GPS unit. I was very dismayed as the expensive GPS unit fell into the water promptly after I placed in what I felt was a secure spot on a half submerged log. I instinctively thrust my hand into the water after the unit to immediately retrieve it, but I was too late. It didn’t work for the rest of the night.

After our first snake we split up, Sean focused on the main pool of the swamp while I was nearer the shore, pushing shrubs out of the way as I navigated around tupelo trees, the water up to my calves. The beam of light from my headlamp caressed the outlines of reed bunches and tussocks of emergent vegetation in the water. And then, suddenly, a snake. After looking at 100 bunches of grass that looked identical, I made out the outline of a snake’s head at the base of one. I hesitated, convincing myself that this was one of our target animals before I yelled out. I traced the outline of the snake as it wove in and out of some emergent vegetation. It was facing the water, perhaps waiting for a hapless frog to swim by to eat.

I yelled out, “Here’s one. Snake!”

“Alright, I’m on my way”

“Do you want me to take it?”

“Do it!”

I heard splashing noises signaling Sean’s impending arrival. I knew that cottonmouths at this site were skittish and I didn’t want it to get away before he got there. But I hesitated, although I have considerable experience with eastern diamondback rattlesnakes and timber rattlesnakes,I’m usually on solid ground when I deal with these snakes. Catching a venomous snake in the water was something I’m not familiar with. However, the chance of losing a snake and never living it down persuaded me to make a move. Before the cottonmouth could react it was within the grasp of my tongs and it was quickly processed.

As we worked our way around a beaver dam, searching along downed logs and vegetation bunches, Sean warned me of a deep beaver channel. “You may want to crash through this brush right here if you don’t want to get soaked to your chest.”

Even though I had recently lost my balance and fell into the water, soaking myself already, I decided to take the high ground. The reeds were taller than me as I used my tongs to part a pathway through the vegetation. I disappeared into the brush, glancing downwards occasionally to ensure I wouldn’t trip over a submerged log. It was then that I noticed the triangular shaped head about two feet from my leg.

“Another snake!” I yelled out again.

I didn’t know if I’d be able to grab the snake through all the vegetation, but if it spooked and swam off then I wouldn’t be able to tell which direction it went, even if it decided to head towards me. So I thrust the tongs through the reeds and was able to secure it. Sean quickly appeared behind me to get a better grasp and helped pull the snake out.

It was getting late at this point but only four minutes after we released the last cottonmouth, Sean spotted a plain-bellied water snake slowly making its way through the grass. He quickly grabbed it and took some weight and mass measurements. Finally, after releasing the last snake, he suggested we call it quits for the night. Overall, we observed a great diversity of animals, including three species of snakes, and saw bird-voiced treefrogs, gray treefrogs, cricket frogs, and green treefrogs breeding. But it was a week before Sean’s GPS unit started working again.

In Over My Head

This column was originally written in July 2008.

Summer is in full force in southwest Georgia and afternoons outside can be sweltering. The heat can be oppressive, even many snakes and lizards choose to spend their days in underground burrows, where it may be cooler.

So, I didn’t hesitate for long when another graduate student at the Center offered me the opportunity to accompany him on a turtle surveying trip in nearby Spring Creek. Now, I should tell you that turtle surveys are basically an excuse to go snorkeling and that’s exactly what I feel like doing after sweating under the sun. The only setback was that due to a 2:00 p.m. meeting of mine, we’d have to get in the water at about 10:00 a.m., a few hours earlier than normal surveys. No problem, I thought.

I met Sean and Brent at the lab and we got our gear together. Did I want to bring my wetsuit they asked? Now, I’m a native New Yorker and I pride myself at not complaining about the cold, at least not in front of any of my friends from Georgia. So, I quickly explained that I wouldn’t need my insulated wetsuit, I mean, how cold could a South Georgia creek be? Brent and Sean exchanged a look.

“Okay, I’ll bring it…just in case.”

This proved to be a wise decision.

After a short drive we unloaded our canoe and stepped into the water. Brent uttered a high-pitched squeal as it lapped at his calves. It’s cold, his shriek indicated.

Our plan was to take a short canoe trip to one of Sean’s study sites where we would unload our gear and snorkel 500 meters downstream (a trip of about an hour and a half). Once we reached the 500 meter mark, we’d turn around and snorkel back to the canoe. Sean’s research aims to determine how river turtle populations are influenced by surrounding land use. He’s sampling turtles by trapping and by hand capture (via snorkeling) in relatively pristine creeks surrounded by forests and in areas that are more impacted by land uses such as agriculture. By comparing what he finds in the different areas, he’ll be able to see if and how turtles are affected.

It was a short trip to our starting point and a single foot in the water quickly convinced me that I would put on my wetsuit after all. The rest of my gear included flippers, gloves and a snorkel and goggles. Our job was to keep our eyes peeled for any turtle of any size. This is trickier than it sounds, different species prefer different habitats and vary widely in color and patterning, once we establish a search image in our head, it’s sometimes hard to see anything else.

After we spotted a turtle, we needed to catch it so Sean could measure it and make marks in their shell so he could recognize it if it was captured again. Although turtles have a reputation for being slow, a few minutes trying to swim after one will quickly dispel that notion. Our flippers evened the playing field somewhat.

I braced myself and submerged, inhaling sharply as the cold water reached various portions of my body. After a few moments of searching through a maze of underwater roots near the shoreline, I spotted a loggerhead musk turtle (on right). It was perched on one of the roots, craning its long neck towards me. This small, brown turtle is often caught by fishermen; it’s not a picky eater and loves to feed on carrion and small invertebrates, including worms. I quickly grabbed him, careful to keep my fingers away from its jaws. Although small, they have a legendary bite. I handed the turtle off to Sean for him to process and dove underwater. Sean's semi-aquatic, mobile, turtle-processing lab is demonstrated below.

After about 20 minutes, I started to feel a tingling sensation in my foot and I assumed that the tight flippers had started to cut off my circulation. No problem I figured, I’d just periodically take off the flippers and allow the blood to flow back into my foot.

It wasn’t long before Brent started to find turtles as well, quickly bringing a yellow-bellied slider and river cooter back to Sean. The slider is an abundant southeastern species and it’s a habitat generalist, meaning it’s found in a wide variety of wetlands from creeks to small temporary ponds. The cooter, on the other hand, is rarely found in areas other than riverine systems. When it comes to diet, the slider isn’t picky there either, eating everything it can fit in its jaws. This species is the turtle most often caught in traps baited with sardines. The more vegetarian cooter, however, is not as vulnerable.

The turtles tended to prefer one of two kinds of habitat. We found sliders and cooters in brushy areas, where the current had consolidated branches and other riprap (these areas also held largemouth bass and big bream) and we also found lots of turtles hiding under submerged logs in deep holes. These logs are considered deadhead logs, left over from the days when the forests were intensively harvested and the wood was floated downstream. Left behind for decades, they are now excellent turtle hiding spots.

One of the more exciting finds was an adult female Barbour’s map turtle. Map turtles are often restricted to single river systems, for example, the Barbour’s map turtle can only be found in drainages associated with the Apalachicola. Other species of map turtles can be found in other rivers. Males and females of this unusual species are strikingly different. Females can be three times the size of tiny males and have huge, broad jaws that they use to crush the mussels they eat.

We hit the halfway point right on time. As we paused before turning around I noticed that the tingling sensation had spread to my hands as well. In the excitement of swimming in the creek and catching turtles I didn’t notice the cold. The blood had left my extremities to keep my core warm, and as a result my hands and feet had gone to sleep. I looked for a sunlit spot on the bank and I began to shake my hands around wildly to get the blood flowing again. Brent and Sean also began to feel the effects; our teeth chattered when we spoke to each other and our hands shook mightily when we tried to help Sean write down data. Without compromising our survey, we tried to cover the water back to the canoe as quickly as possible. We continued to find turtles, but we did so reluctantly, and they were processed as quickly as possible.

When all was said and done we had captured twelve turtles of four species, not a bad haul and important data for Sean’s project. I’ll help again, but I’ll have to make sure that we do so in the afternoon when the water’s warm. I suppose there was at least one upside; perhaps the cold water is what deterred any curious alligators from taking a closer look.

Monday, March 23, 2009

From Dusk 'till Fawn

This column was originally written in August 2008.

A few weeks ago, Brent Howze needed my help finding white-tailed deer fawns with a $12,000 heat-detecting camera before coyotes or bobcats got to them first. Although it meant a late night, I agreed to give it a shot. Brent is a University of Georgia graduate student and he’s studying fawn mortality; by capturing newborn fawns and monitoring their activity, he can determine the influence of predators on deer populations.

Historically, panthers and red wolves patrolled the southern pine forests, eating and outcompeting smaller predators such as bobcats and raccoons. When these big predators became locally extinct due to overhunting and habitat loss, the smaller predators increased in number as a result. Also, coyotes invaded from the west, taking over the niche previously occupied by wolves.

For many years, smaller predator populations were kept down by trappers after their fur. But over the last few decades, both interest in this activity and demand for fur has steadily decreased, resulting in higher numbers of raccoons, bobcats, coyotes, etc. This isn’t necessarily a bad thing, but wildlife biologists are eager to know how these changes have affected the ecosystem.

That’s where Brent comes in; this time of year does often temporarily leave their fawns behind as they graze for food. Fawns are virtually scentless and highly camouflaged, their primary defense is to lay perfectly still in the grass. But they still give off heat and Brent has a secret weapon to exploit this.

At night, Brent hooks up a television to his truck’s battery and places the tv in the bed. To the television, he plugs in his heat-detecting thermal camera, an expensive piece of equipment. Images from the camera are transmitted onto the television for easy viewing. Pointing the camera in the dark night reveals a hidden world.

The outlines of trees, rocks, and bushes are various shades of gray but easily distinguishable. The warmer an object is, the lighter it appears. The camera is so sensitive that we can easily make out rats and mice hiding in the weeds, their body heat causing a bright white ball to appear on the screen.

I thought my job was to drive the truck through the woods while Brent kept a close eye out for any white blob that might be a hidden fawn. He quickly informed me of some additional duties: if he saw a fawn, he’d alert me and I was to stop the truck and jump out with a giant net. Brent would guide me towards the fawn by viewing my progress on the television and at his cue I’d pounce forward, hoping I could capture it before it bounded away. Once captured, the fawn would be fitted with a radio collar, allowing Brent to keep an eye on it with an antenna. I solemnly acknowledged my responsibilities, adjusted my head lamp, and put the truck in drive.

I slowly navigated the dirt roads, occasionally distracted by a miniature screen in the front seat that allowed me to view through the camera as well. It wasn’t long before we both noticed three white blobs in the grass. What is that? I heard Brent mutter. Some quick birdlike movements and the animals revealed themselves, a covey of bobwhite quail. We drove on.

Then there were several armadillos, their turtle-like shell was immediately recognizable as the unusual creatures shuffled across the ground looking for insects and grubs to eat. When we first spotted a deer, its form looked gigantic compared to all the small critters we had seen. Brent flicked on his 500,000 candlepower spotlight; the doe was illuminated only about ten feet from the truck but we never would’ve had a clue it was there without the thermal camera.

Unfortunately, the doe was without a fawn nearby, a trend that continued through the night. Although we spotted nearly 30 deer, they were all adults or nearly so. One huge buck lay in the grass a few feet from the road; its broad, velvet-covered antlers included a drop tine. After briefly viewing him with the spotlight, he lazily rose to his feet and slowly sauntered off. He might make some hunter happy this fall.

A successful capture from a previous effort
At about 11:00 we briefly saw three or four large shapes through the camera. By the time I slowed the truck and backed up to a better vantage point, the shapes had quickly slinked away into the night. They were gone before we could get a good look at them. Coyotes, Brent told me. They are fascinating animals, in the west this species is relatively small and solitary but as they’ve expanded their range eastward their size and behavior has shifted. They’re larger here, which enables them to hunt larger prey. It’s almost as if they’re acting like the wolves that used to be found here.

At midnight we called it quits, the night was a bust for catching fawns. But we know they’re out there, the next day Brent found some coyote scat and on closer inspection (a particularly unglamorous part of his job), he noticed a pair of small hooves in it.

Sunday, March 22, 2009

Shell Shocked

This column was originally written in September 2008.

Our mission: upon locating North America’s largest species of turtle, pry it out from under the submerged logs and limestone caves on the bottom of frigid Spring Creek, taking great care to avoid its prominent jaws as we brought it to the surface. Easier said than done.

The alligator snapping turtle is found primarily in the southeastern United States in rivers and creeks that drain into the Gulf of Mexico. They can reach over 200 lbs, although they’re seldom that big. A beast of a turtle, they prowl creek bottoms searching for dead fish to eat. A turtle this size has few natural predators, patrolling its riverine hideaways with impunity. And yet, we almost lost it forever.

Close your eyes and picture a can of turtle soup. This is the closest that many people have ever gotten to an alligator snapping turtle. After decades of unregulated harvesting, populations of this species declined precipitously. Protections were recently put in place and these turtles have slowly started to rebound, but it’s a precarious recovery and populations are still vulnerable.

This species is a secretive and rarely studied animal; but John Jensen of the Georgia Department of Natural Resources is researching a population in southwest Georgia. By trapping for turtles over many years, he can estimate the size of the population based on how many individuals he recaptures. These efforts also provide baseline data necessary to monitor the population and determine if it’s stable.

Once a year, John supplements his normal trapping routine by inviting biology graduate students and his colleagues for a snorkeling trip in an attempt to root up some turtles that have eluded capture. We met early at the public boat ramp before the crowds arrived to cool off in the water. It was a large group this year, about 20 people. Some had brought their SCUBA gear; they knew what they were in for. I looked forlornly at my snorkel and wondered how long I could hold my breath while wrestling with a giant turtle.

After a brief introduction to our mission (the only reason we were able to handle these protected animals is because we were helping a state biologist), our fleet of kayaks and canoes slipped into the water and headed downstream to the study site. I was content to float along but others quickly donned their gear and submerged. I saw snorkels crisscrossing the creek and bubbles burst through the water’s surface as divers explored the depths.

It wasn’t long before I started seeing hands full of turtles thrust skywards as Barbour’s map turtles, yellow-bellied sliders, and river cooters were found. Although these weren’t the species that we were targeting, they still provided valuable information. One student even collected leeches for a parasite study.

As the morning waned, our flotilla dispersed widely. But suddenly I heard some news that had spread quickly among the trail of boats. One of the SCUBA divers had found a snapping turtle.

I muscled my kayak around and doubled back, paddling against the current until I reached a crowd of boats floating around a mass of giant logs and trees lying flush against the steep banks of Spring Creek. Apparently there was not one, but two giant alligator snapping turtles wedged in a submerged cave. A strategy had to be crafted, the turtles were too far back and in too tight to simply be dragged out. The divers submerged repeatedly with no success. Finally, from the depths came a massive turtle, firmly within the grasp of one of the intrepid biologists.

The beast’s massive jaws gaped menacingly, daring us to let a careless hand stray too closely. Water poured off its serrated shell, sufficient protection from any predator besides us. The turtle was carefully maneuvered to shore, where it was measured and marked for future identification. After a few photos, we allowed the 40 lb animal to slip back into the creek. In the excitement, the other turtle had given us the slip as well, and we didn’t catch another turtle on this trip.

When we reached the designated end of our survey, we were free to enjoy the scenery. At our start point, Spring Creek is small and almost completely shaded by overhanging trees. But as we flow south the water flow becomes increasingly influenced by Lake Seminole. The creek opens up widely and marshy areas are more common. Good habitat for alligators, not so great for snorkeling.

Despite our day-long effort, the miles we covered, and all the seasoned turtle biologists on the trip, we caught sight of only two alligator snappers. We have no way of knowing how many we missed, surely there are more prowling the depths. But our efforts indicate how the loss of only a few individuals may resonate within a creek.

Saturday, March 21, 2009

In the Heat of the Night

This column was originally written in January 2009.

Last month, I traveled to Atlanta to visit a “Dialogue in the Dark” exhibit, wherein participants are plunged into total darkness and led through several scenarios and arenas by a blind guide. The formal goal of this exhibition is to promote awareness of blind and similarly disabled people by enabling participants to experience life as they do. I suspect that many ticket holders aren’t entirely selfless and also visit for the thrill and the novelty. I’d like to say I was in the former camp, but there was admittedly something about stumbling around in the dark that sounded exciting.

As I approached the entry point of the tour, I was provided with a cane and lead to a seat in a weakly lit room. I was pleased to see that there were several young, giggling children present. If I were to get separated from my group, I schemed that I could follow the sound of their shrieks back to safety. The lights slowly dimmed as a resonating pre-recorded voice reassuringly introduced the exhibition. It gently informed us that darkness is often associated with danger, but this is seldom accurate. Just seldom? A wave of anxiety passed over me as I was enveloped by the inky blackness of pure, unadulterated darkness.

Out of nowhere (but then again, so everything seemed in the dark), we heard the voice of our tour guide instructing us to slowly stand and make our way towards him. And so began our dialogue. I’ll save you from the details; I recommend you experience the tour yourself, but as I stumbled through the various rooms and scenarios, leaping away from the inquisitive hands of my sightless companions (there was more awkward groping than at your typical high school prom), I envied snakes.

We humans like to think that we are the pinnacle of biology, perfectly suited for any situation. But, we tend to stick to circumstances that we’re comfortable with, restricting most of our activity to the daylight hours. There are actually entire senses that we completely lack, including the ability to detect heat. In the woods, in the dark, it is this sense that allows pit vipers to find their prey.

There are five species of pit vipers in our region, including cottonmouths, copperheads, and timber, diamondback and pigmy rattlesnakes. Ever wonder why they’re called pit vipers? Each of these snakes has a small opening in front of each eye that leads to an organ that can detect infrared rays given off by heat.

Light is made up of different wavelengths; the length of each wave determines what color we see. But there are waves with lengths well beyond what humans can detect. Infrared rays are made up of wavelengths in this category.

Infrared rays hit a membrane within the snake’s pit organ; where the rays hit signify to a snake the relative location of a warm prey item. Warm objects stand out against a colder background (watch the movie “Predator” for a stylized representation) and since a snake has a pit on each side of its face, it’s able to pinpoint the location of unlucky mice or rats that scurry by.

It’s a surprisingly accurate system; you just try to grab a mouse with your eyes closed. The pit organs are so sensitive, vipers may detect when something is 0.4 degrees Fahrenheit (or less) different than its surroundings.

Who needs eyes when you can see heat? A pit viper would not have been as awkward in the dark as I was, tripping over my cane, trying to get my bearings, all while attempting to figure out what I was touching, which at least once included someone’s backside. As to how warm it was, I couldn’t accurately say.

Thermal camera photograph of yours truly courtesy of Richard Bryant

Friday, March 20, 2009

Diamonds on the Move

This column was originally written in fall of 2008.

Last weekend I came face to snout with the magnificent king of the longleaf pine forest, the eastern diamondback rattlesnake, Crotalus adamanteus. I was in south-central Alabama, driving slowly along some dirt roads in Conecuh National Forest when I saw him slowly make his way across my path. He was as stately as a snake could be, his slightly arched back prominently displaying the golden-bordered diamonds checkered across his body. It was an exciting discovery.

The eastern diamondback is the largest rattlesnake in the world and it’s known only from the southeastern United States. Although this impressive animal can be abundant in some areas, populations of this species are declining throughout their range. Whenever I have the good fortune to find one, it’s an exhilarating experience. This snake was a large mature adult, probably almost four feet long. I admired the unique tail, without getting too close, I counted about ten rattles. Rattlesnakes don’t add a rattle each year, as is commonly thought, they add a rattle each time they shed their skin. This happens frequently when a snake is young and growing fast but less often once a snake reaches maturity.

It’s fall, which means it’s time for these usually extremely secretive animals to start crawling around looking for mates. Although most people associate the spring with the birds and the bees, diamondbacks conduct their business in September and October. It takes them about a year from mating to produce a litter, giving birth the following fall. This is a big investment for the snakes and they likely only breed once every few years.

I knew better than to get too close. These venomous snakes command respect and it’s not worth taking a chance. I sometimes need to handle this species for my work, and when I do so I am extremely cautious. Most of the nature shows on television are more sensational than realistic. They often give people the wrong impression regarding the proper way to handle dangerous animals.

Because of their potentially dangerous nature, rattlesnakes are much maligned and feared. Many interactions between people and snakes result in a dead serpent. But attempting to kill or harass a rattlesnake is much more dangerous than walking the other way. The overwhelming majority of reported venomous snake bites occur on people’s hands and arms. Now, if they were minding their own business, what do you think the chances are of getting bit on their hands by a snake?

About two weeks ago, a central Georgian man was bitten by an eastern diamondback rattlesnake and required emergency care. This is a tragic incident but not the whole story. When he saw the snake crossing the road, he proceeded to drive over it multiple times with his tractor and then attempted to beat the still-writhing animal to death with a deer antler. The snake bit the man between his fingers before its head was cut off with a shovel. Fortunately, the man survived.

The entire incident could have been easily avoided. How? By letting the snake finish crossing the road.

When a snake is encountered in natural settings, it’s not safe to go out of one’s way in an attempt to kill it, it’s dangerous and it doesn’t respect the role that these animals play in natural environments. They have many jobs, eating rodents perhaps primary among them.

However, when you have rattlesnakes in your yard and you’re concerned about your children or pets, it’s understandable that you’d want them gone, and quickly. Instead of finding ways to get rid of snakes, it may be more effective to dissuade them from ever establishing residence in the first place.

If there’s one thing that snakes love, it’s hiding places. If you don’t want snakes around your house, make sure to remove any brush piles. These animals often hide in stacks of wood. Keep lawns mowed and bushes trimmed so that they don’t reach the ground, this eliminates cover for snakes. Although much has been said about commercially available snake repellents, their usefulness has not been clearly demonstrated.

There’s no denying that rattlesnakes are potentially dangerous. But by using some common sense you can virtually eliminate your risk of a bite. If you’re concerned about your children, make sure they can identify potentially dangerous animals and teach them to give vipers a wide berth. Always watch where you put your hands and wear appropriate footwear if you’re in snake habitat. No sandals! A snake minding its own business is not likely to bother you. If you see a snake in nature, just leave it alone.

The rattlesnake I found last week sure wasn’t interested in me. After I took some photographs from a safe distance, it slithered away into the wiregrass. Once it reached the forest, the snake’s camouflaged patterning made it nearly invisible. I wondered how many I walk by without ever knowing they’re there.

Thursday, March 19, 2009

Gone on a Bender

Snot Otter. Devil Dog. Mollyhugger. Alleghany Alligator. Intimidating names sure to unnerve the most intrepid explorer, yet they all refer to the same diminutive beast, a beast I was to spend the weekend trying to find in the mountains of northwest Alabama.

Of all its names, Cryptobranchus alleganiensis is most commonly referred to as the hellbender. It’s the largest salamander in North America, and by far. Reaching over two feet long, the hellbender prowls the depths of pristine, mountain streams looking for crayfish to eat. Picture a giant brown, chunky salamander and you’ve probably got a pretty good idea of what they look like. They have a flattened appearance, which helps them fit under rocks when they’re hiding, and small beady eyes. Hellbenders can be found all the way from southern New York to the creeks meandering through the mountains of north Alabama and Georgia, yet populations are in decline throughout their range.

These giant salamanders are in trouble: although dams, over-collecting for the pet trade, and wanton killing all take a toll on populations, perhaps their primary threat is siltation. Agriculture and development both lead to increased silt in streams, which smothers the rocky habitats the hellbenders need to survive and reproduce. Hellbenders prefer clear, clean streams with lots of rock cover. They mate and nest under large rocks; males will protect the eggs until they hatch, providing them oxygen by circulating the water with movements of their body.

Only a handful of hellbenders have been observed in Alabama over the last decade, all within the same general region: the creeks and streams nestled in the valleys in the state’s northwest corner. To determine if these sporadic observations were signs of a healthy, breeding population, a few Auburn colleagues and I suited up and prepared for a five hour drive.

Jim and Faye Lacefield began purchasing land in the area almost thirty years ago, culminating in over 400 acres of what is now known as the Cane Creek Canyon Nature Preserve. Their objective was to conserve a unique ecosystem that was under threat of impending human encroachment and development. However, they’ve never had the intention of keeping it to themselves; the Preserve is open to hikers, nature enthusiasts, boy scouts and anyone else that wishes to enjoy the scenic vistas, the majestic waterfalls, or look for snot otters. Can you find the hellbender in the picture on the right? The stream represents nice hellbender habitat elsewhere.

On Saturday morning, Jim met us at the Preserve to show us some creeks that could potentially harbor hellbenders. As we took in the scenery, we became particularly interested in some of the caves and overhangs we passed. They looked like perfect habitat for a number of interesting amphibians, like slimy, cave, green and dusky salamanders. But those could wait, we were after bigger prey.

We were encouraged by the vast expanses of hardwood forest on the property. These forests prevent erosion and keep silt from entering the pristine streams. Although the clear creeks had many promising rocks scattered throughout, the water flow was low. We decided to give it our all but we weren’t optimistic; since the creek was so shallow, it wasn’t a stretch to assume that it periodically dried up completely, suggesting that hellbenders couldn’t persist here. The strategy was simple; I was to lift rocks while my frequent field companion, Sean Graham, thrust his hands underneath to feel for the slimy form of a giant salamander.

Some of the rocks were huge and tested my strength. As I strained to keep them upright, I occasionally yelled at Sean to hurry up so his outstretched arms wouldn’t get crushed by a rock slipping from my grasp. After about an hour, we started to tire. Although we found many crayfish, there were no hellbenders to eat them.

There were also lots of small dusky salamanders crawling around the stream. At one point I felt an odd wriggling from within my sandal, as I lifted up my foot to investigate, an inch-long dusky salamander fell out and splashed into the water. If only the hellbenders were this easy to find.

We decided to return that night to investigate the several caves and look for some other animals. After dark, we probed the many crevices with the beams of our headlights and found numerous small salamanders hiding within cracks.

Many revealed only their face, perhaps waiting for an unlucky cricket to wander by. When I spotted them, they quickly ducked back into their holes.

I also found a worm snake within a cluster of grass, a species I had never seen before. This snake is small, less than a foot long, with a bright pink belly. It’s rarely found above ground and, as its name suggests, eats primarily worms.

The next day, we began the long, solemn drive back to Auburn. Over the weekend, we managed to see about 16 different kinds of amphibians and reptiles, including black kingsnakes and pickerel frogs, species which are hard to find elsewhere. But the status of hellbenders in Alabama remains a mystery and is likely precarious. The last sighting in the state was in 2006, a large dead adult found floating down a mountain stream.

The author and a hellbender survey crew on a
previous effort in northeast Georgia in 2005

The column originally ran in November 2008

Hellbender photos courtesy of Jeff Humphries

Wednesday, March 18, 2009

Hopper Poppers

            I’ve eaten bugs.  I can’t honestly say it was by accident either, because I went online beforehand to look for recipes.  Now, before I lose you completely, let me explain myself.
            A few years ago I read an article about a man that was attempting to promote insects as food in the United States (and he’s not the only one). Insects, he argued, are an abundant food source and a more sustainable form of protein than the animals Americans typically eat, particularly cows.  Raising cattle can be costly; each cow requires a vast amount of resources before they can be consumed.  In fact, more energy goes into raising cows than we get back from eating them. Plus, cattle can produce a lot of greenhouse gases. Together with concerns about antibiotics and growth hormones administered to livestock and animal welfare issues associated with large, factory farms, some have grown dissatisfied with the system.  Insects represent a food without the baggage.
            That’s not entirely true, I suppose, as bugs could benefit from a public relations campaign.  After all, they’re gross.  But I was intrigued by the prospect of a cheap source of protein and my thoughts kept drifting to all the grasshoppers that would fly out of my way when I walked through the field next to my house. I kept telling myself that eating insects wasn’t really all that unusual, after all, many cultures have eaten insects throughout history.
            When a friend announced that she was hosting a potluck dinner with the requirement that dishes needed to contain ingredients that we foraged for ourselves, I had the excuse I had been waiting for.  I would make fried grasshoppers.  I started referring to them as hopper poppers, hoping a catchy name would remove images of antennaes and wings from everyone’s thoughts.
            Catching the grasshoppers proved to be more difficult than I had planned.  I didn’t recall have any problems catching bugs when I was a kid (no, I didn’t eat them).  But after I ran around my yard pouncing after grasshoppers, I was left sprawled on the ground, arms outstretched in a futile attempt to grab one.  They would see me before I could see them; grasshoppers erupted out of the grass and flew away as I walked, always just out of reach.  I hoped that nobody was watching.  Don’t mind me, I’m just trying to get something to eat, I imagined explaining.
            A change in strategy was warranted.  After borrowing a sweep net I was ready to try again.  I rapidly swung the net back and forth in front of me as I strode through the tall grass, hoping that I was snagging grasshoppers as I went.  It was tiring work.  After about ten minutes or so I ventured a glance into the net and I was pleased to see a wriggling mass of insects at the bottom.
            I kept the grasshoppers alive overnight so they’d have a change to purge themselves of anything in their digestive system and then I placed them in the freezer.  After a quick bake in the oven to ensure they were cooked through, I dipped them in egg and breaded them in a mixture of flour, bread crumbs, garlic powder and oregano.  After that, they only needed to be deep fried for about 20-30 seconds before they were crisp and golden brown.  My roommate used about 20 grasshoppers to dip in melted chocolate. 
            So there we were, standing in our kitchen looking at about 100 prepared grasshoppers.  All that was left was to eat them.  With a deep breath, I closed my eyes and threw one in my mouth.  They were good!  They tasted just like anything else you might deep fry.  Although the recipe called for removing the wings and legs, we decided that the ones I had caught were so small it would probably be okay to leave them on. Nevertheless, I will probably remove these parts next time (if there is a next time), or at least have a toothpick handy.
            When we arrived at the potluck, everyone wanted to see me eat one first so they knew this wasn’t an elaborate plan to get them to eat bugs while I laughed.  After I obliged, everyone tried at least one.  Elaborate ruse or not, I still thought it was funny.

Thursday, March 12, 2009

Long Walks on the Beach...

Although Mother Nature has recently offered some tantalizing glimpses of the impending spring weather, it’s been bitterly cold lately. So cold that I would not have been motivated to take a stroll through the woods even if there had been any critters crawling around. Just as all the snakes have been coiled in their dens and underground caverns, I have been holed up inside, on my couch. It’s a time for quiet reflection, for remembering warmer times and places.

About eight years ago I visited Costa Rica in a quest to find exotic reptiles. A highlight of the trip, and of my life, was the night we visited Tortuguero, a sea turtle nesting beach on the Caribbean coast.

At Tortuguero is found the Caribbean Conservation Corporation , an organization created in the 1950s to protect and better understand the plight of the critically endangered sea turtles that nest in the area. At night, we met with researchers to guide us as they searched for turtles along the moonlit shore. As we marched along the shoreline, my eyes kept drifting to the dark and menacing jungle that began immediately where the sand ended. The forest harbored jaguars, lots of them, and they were patrolling the same stretch of beach. Sea turtles are an important food source for the big cats; they killed and ate dozens of them that nesting season.

We had only the moonlight to guide us. Flashlights disturb the turtles and were forbidden. I squinted in the dark to better make out any turtle trails in the sand before me; these are the telltale signs of a female nesting nearby.

We walked for hours as the waves lapped against the beach and my oversized rubber boots rubbed my calves raw, yet we saw no turtles. The night wore on as we diligently marched and we had covered about four miles by the time we had returned. Disappointed and exhausted, we slumped into anything that would hold us and rested our eyes.

No sooner had our eyelids begun to slowly lower did garbled voices spring from the researchers’ radios. What was going on? I strained to make out the conversation. Another group had located a turtle down the beach. Did we want to go, the researchers asked? I have to admit that I hesitated briefly, I was so comfortable after our long arduous hike, but I quickly got my second wind. As we marched towards the other group, we caught word that the nesting turtle was a leatherback and our excitement soared.

Leatherback sea turtles are one of the largest reptiles in the world. The biggest on record measured nearly ten feet long and weighed over 2,000 pounds, that’s a huge turtle. But their size isn’t all that makes them special. They’ve been documented diving to depths in excess of 1,000 yards (10 football fields), they eat poisonous jellyfish, and their warm metabolism allows them to inhabit the cold water of the northern oceans. They’re truly a unique animal. But they’re declining worldwide.

Leatherbacks are critically endangered. Major threats include accidental capture by fishermen, over-harvest for food, pollution, and destruction of nesting sites. Turtles also eat plastic bags that have made their way into the ocean; the turtles are unable to distinguish between the bags and their jellyfish prey. The mistake is often fatal.

Turtle populations aren’t accustomed to experiencing high levels of adult mortality. Of the many young that are produced each year, only a few escape the hungry eyes of seagulls and large fish. This makes breeding, adult turtles especially valuable, and now, after a long, arduous, late-night hike, one was suddenly before me.

The researchers were working with flashlights covered by a red film; this keeps the light from disturbing the beasts while nesting. A weak beam of light briefly illuminated the turtle’s basketball sized-head; I glimpsed one of her eyes and was in awe. Many years ago, this turtle likely emerged from a nest on this very same beach. For decades she had defied the odds, reached a huge size, and returned to deposit eggs of her own. And I was here to see this feat of nature.

When the biologists gave us the okay, I reverentially ran my fingers along the length of her five-foot leathery shell and gently grasped one of her giant flippers. I don’t know how long we watched her; I lost all sense of time. After the ancient turtle had dropped perhaps 80 eggs, she used her back flippers to fill the nest with sand.

Nesting complete, the turtle made her way back to the sea. Her flippers were made for swimming the open ocean; her awkward motions seemed out of place as she flapped and floundered her way to the water. It was a most inglorious ending to an otherwise graceful event.

As we made our long way back along the beach, I was on a high. It hardly bothered me when someone pointed out some fresh jaguar tracks alongside the footprints we had left earlier. The tracks hadn’t been there when we crossed the first time.

Photo of leatherback sea turtle courtesy of the Caribbean Conservation Corporation /

Wednesday, March 11, 2009

Hanging By A Thread

On a brisk night last fall, I found myself hanging off a moss-laden cliff, clinging to a rope for dear life and trying not to look down. As the light from my headlamp careened around the wall of dirt in front of me, I cast furtive glances upwards, silently willing the rope to hold me and the knot to stay wound around the tree above. A tree which appeared sturdy enough earlier but now seemed to be giving a little too much. I took a deep breath, closed my eyes, and tried to focus on the task at hand; I was here to capture one of the rarest animals in the world, the federally threatened Red Hills Salamander.

This salamander, Alabama’s state amphibian, is found solely in south Alabama, and in very specific habitats. To my great misfortune, these specific habitats are steep slopes and ravines. I vainly tried to gain a foothold among the loose dirt clods on the cliff, gingerly moving so that I didn’t disturb the ground or accidently squish a salamander as miniature avalanches of dirt and small rocks cascaded down around me.

Red Hills salamanders live nearly their entire lives in small burrows on these cliffs, often only their head is visible as they peek out from their subterranean caverns. They’re thought to rarely leave them. Unlike many other salamanders, hatchlings do not develop in water, females lay eggs within their burrows and that’s where the young are born. Interestingly, the hatchlings possess gills for their first few days of life, perhaps a reminder of their more traditional ancestors.

Red Hills salamanders have a few things going against them. Due to their extremely small range (five counties in south Alabama) and their specific habitat requirements (steep slopes), there just aren’t a lot of places for them to live. Combine that with logging practices that degrade their homes and it’s easy to see why the salamander is in trouble.

The inevitable march of human “progress” is stepping on this rare species. I was helping a colleague, contracted by the state, capture all the salamanders on this cliff before a road construction project destroyed the entire area. It’s a common misconception that endangered species often halt construction and development projects, what typically happens instead is developers first make some concession to limit their environmental impact and then proceed as usual. When the next project comes along, they make another concession, and so forth. It’s not surprising why it’s hard for endangered species to recover, although there are some success stories.

As I swung back and forth looking for salamander burrows, my waist harness creeping up uncomfortably, I figured that there must not have been a large concession. Our goal was to catch salamanders here so they could eventually be relocated elsewhere. It was a risky proposition as there was no way of knowing if the relocated salamanders would take to their new home, but it was better than the alternative, (i.e. leaving them to get paved over).

About an hour after arriving, my headlamp suddenly illuminated what I thought was an eyeball. When only their head is visible in their burrow, it’s hard to imagine how big Red Hills salamanders can grow, nearly a foot long. These slender animals are a nightmare to any unfortunate cricket that might stroll by their burrows. In a flash, the salamander will emerge, mouth agape, to grasp any insect that it can cram down its gullet. I trained my light on the little cavern and slowly maneuvered closer for a better look. A salamander face looked back at me. I reached into my pocket for a bag of crickets, moving very slowly to avoid scaring the skittish creature back into the depths.

It takes some finesse to catch these animals. There’s really only one reliable method: fishing for them. Still moving as slowly and deliberately as possible, I impaled a hapless cricket onto a barbless hook and gently placed the insect in front of the burrow. I should interject here that we took every precaution to minimize stress on the salamanders; we likely wouldn’t have used this method if it weren’t so important to catch and relocate the animals. This was a specific conservation effort sanctioned by state and federal authorities.

When the salamander detected the cricket, it was instantly interested and on the prowl. With focused intensity, the amphibian zoned in. Mirroring the salamander’s concentration, I willed it to take the bug bait. Seemingly in slow motion, the salamander began to open his mouth. This was it, I readied myself. It continued to open its mouth so wide that it could no longer see the cricket, understandably reducing its aim. As I watched the salamander awkwardly miss the cricket several times, I wondered how they ever catch enough food to survive. Eventually however, the salamander did figure out the right angle, and I quickly secured the animal. As I gently removed it from the burrow, I admired the strange creature in front of me.

Red Hills salamanders not as bulky as other amphibians you might see, they’re long and slender with greatly reduced limbs. Overall, it reminded me of a worm. An unflattering description, but they’re surprisingly charismatic, perhaps because of their large, inquisitive eyes. I gently removed the hook and placed the salamander within a small tube, we hoped it would remind it of its burrow.

I waited until the salamander was safely secured in its tube before I yelled to the others that I had caught one, the first of the night. They responded with their praise. I was starting to get the hang of this whole night mountain climbing thing after all; I could hardly notice the creaking rope, the dark abyss below me, or the intimate relationship I had developed with my harness. I managed to catch another salamander, two of several captured that night.

I hoped the salamanders would be content in their new home. They’d be safe for now, at least until they start talking about the next road construction project.


Over a year later, the road construction has yet to occur and the salamanders have been brought back to their original burrows. Due to the large number of salamanders documented in the effort described above, the United States Fish and Wildlife Service required a revision to the original blueprints. The updated plans now require the roadway to miss the majority of the burrows; however, the highway will separate the remaining salamanders.