Tuesday, April 24, 2018

Two Unique Alabama Treasures On the Brink --Guest Post--

Flattened Musk Turtle
Take a minute and think of something unique to Alabama, something you can’t find anywhere else. What is it? Perhaps it’s tailgating on a cool Saturday afternoon after Thanksgiving, for the greatest football rivalry in the South. If you attended elementary school in Alabama, perhaps you thought of the only monument in the world to a pest insect, the Boll Weevil. Some would think of their favorite hunting or fishing honey-hole. Whatever you thought of, I doubt it is what first comes to my mind: the Black Warrior Waterdog and the Flattened Musk Turtle. In fact, most Alabamians don’t even know they exist. Native to the Upper Black Warrior River System, the Black Warrior Waterdog, Necturus alabamensis, and the Flattened Musk Turtle, Sternotherus depressus, are endemic to Alabama, meaning they only occur in Alabama and nowhere else. This alone makes these two species incredibly special, but the curious nature of the Flattened Musk Turtle and mysticism of the Black Warrior Waterdog along with the astounding beauty of the habitat in which they occur establish them as natural treasures. 

Black Warrior Waterdog (Courtesy Mark Bailey)
While conducting studies on these species over the past five years with the Alabama Natural Heritage Program at Auburn University, first as an undergraduate and now a graduate student, I have developed a deep connection and appreciation toward these species and the unique river system in which they occur. Being part of what may be the final generation of researchers to have the privilege of working with them, it is an appreciation I hope to share with you.
            
      The morning fog floating above the water’s surface begins to dissipate as I reach the sandy bank of the Sipsey Fork after a half-mile of kayak dragging. The steep path between bluffs was once an ATV trail. Before that, it may have been a horse and wagon trail used by settlers, and, still earlier, almost certainly was a Chickasaw Indian footpath to access the stream. Now, used only by me and the occasional deer, it is overgrown with briars and muscadine. A sliver of regret develops in the back of my mind over the decision to bring the kayak as I dread the idea of dragging 70 pounds of kayak and gear back up the 200 foot elevation gain to my car. Still though, the Sipsey Fork is uncomfortably cold to be wading in March and the feeling is quickly replaced with contentment as I begin paddling downstream along a colossal sandstone bluff overhanging the water. I steer the kayak between the steady drips of water falling 70 feet from the top of the bluff, avoiding the unpleasant sensation of cold water droplets exploding on my neck.

I paddle to my first trap which is set next to a car-sized submerged boulder. I pull the trap to find nothing but a Sloped Crayfish (Cambarus obstipus) and a couple young sunfish which I release. In the next trap, by a submerged log, I notice a dark, slender shape. My heart begins to race as I pull the trap from the water and the critter becomes visible. To my disappointment, the shape morphs into a small catfish, not my target, which is the rare aquatic salamander known as the Black Warrior Waterdog. I continue to check the rest of the traps, but they don’t yield much else. As elusive as they are, I knew the odds were against me capturing one of those foot-long salamanders.

Bizarre and majestic in their own right, Black Warrior Waterdogs, with their external gills, resemble mythical dragons of Asian lore and are quickly becoming as hard to find. They have declined drastically across their range over the past few decades due to increased sedimentation and poor water quality. Recent surveys indicate that they may have already disappeared from 80 to 95 percent of their historic range. To make matters worse, very little is known about their life history and historic abundances as few studies have been conducted on the species. Because of the lack of research, conservation of the species has been ignored. It is possible that we will lose the Black Warrior Waterdog (one of Alabama’s only two endemic amphibians) within the next couple decades.

My hope was to capture a waterdog at this site, where they hadn’t been previously sampled, to determine the extent of their range within Bankhead National Forest, but that would have to wait another year as the active season for waterdogs was drawing to a close. With traps pulled, I grab my radio telemetry receiver and antenna and turn my attention to another imperiled resident of the Sipsey Fork.

 I switch radio frequencies to a familiar wavelength. “Ping… ping…ping,” the receiver begins its metronomic tune. The volume increases as I paddle closer to the location of the transmitter. I triangulate the location to a submerged slab rock which had broken off the face of the bluff many years ago, perhaps at a time when the Chickasaw were using my path down to the stream. I scan the stream bottom while trying to hold the kayak steady in the current. Suddenly, I feel that rush of adrenaline that hunters can relate to. It’s the feeling you get in the split-second between the pattern recognition of your quarry, say a deer, in your peripheral vision and when you focus on and confirm that it is, in fact, a deer. My eyes adjust and focus in on the familiar sight of a Flattened Musk Turtle poking her yellow head with black reticulations out from under a rock.

The Flattened Musk Turtle gets its name from the uniquely flattened shape of its shell, a direct product of Alabama’s geology. Below the Fall Line, the dividing line between the Piedmont and the Coastal Plain where the Western Interior Seaway existed 100 million years ago, the Black Warrior River is mostly sandy with some small rocks and gravel. Above the Fall Line, however, the Black Warrior River Basin is a heterogeneous mix of bedrock, boulders, large slab rocks, gravel, and sand. This habitat, abundant with rock-crevices and isolated from other river systems, is where the Flattened Musk Turtle evolved.

Over hundreds of millennia, this new species of musk turtle evolved in the Upper Black Warrior that was unlike those found in the Coastal Plain or adjacent watersheds in the Piedmont. It developed a more compressed shell with a flattened carapace, reducing drag and allowing for individuals to lodge themselves deeper into crevices to escape predators and high velocity flow events - an important adaption for a river system with steep canyons that channel water creating extreme currents and exceptionally high flood levels. There were, of course, biological costs to compressing organs and living in these cold upland streams. Females took seven years to reach sexual maturity instead of five and laid half as many clutches per year. However, the wealth of food in the form of snails and great abundance of rock-crevice refuges were worth the costs.

This specialization was a good strategy as long as the streams had plenty of crevice cover. Unfortunately, that habitat has been increasingly altered over the past 70 years. Largely from extensive mountain-top removal, also known as “strip mining,” coal extraction in addition to the state government’s allowance of poor riparian zone management around some land development projects and forestry operations, sediment has inundated much of the Black Warrior Basin, filling in the crevice habitat that is so critical to the survival of the Flattened Musk Turtle. The coal mines have the double whammy of also creating long-term pollution issues that kill off aquatic mollusks (snails and mussels) that the turtles rely on for prey. Historic survey data is robust for the Flattened Musk Turtle and recent surveys indicate that they have been lost from around 70 to 90 percent of their historic range. The story of the Black Warrior Waterdog parallels that of the Flattened Musk Turtle, from their speciation in the Upper Black Warrior to their flattened body shape, and from the population declines to the issues causing them. Likewise, if we push the Black Warrior Waterdog off the cliff of extinction, the Flattened Musk Turtle, our only endemic reptile, will not be far behind. However, if we develop strategic conservation plans soon, we may save both for the price of saving one and, in the process, protect a number of other imperiled aquatic species in the Black Warrior.

This was the first time I had seen the adult female since she became inactive in November under a boulder about 40 feet upstream. I grab my GPS and begin recording data about habitat and location while she continues to watch my every move with curiosity from the comfort of her sandstone retreat. After recording the necessary data, I take a moment to admire this comical-looking turtle. Although only the size of my hand, she has been roaming this stretch of river longer than the 21 years I have been alive. I continue on, tracking other turtles and recording data before calling it a day and paddling back to the take-out. Knocking from a Pileated Woodpecker echoes across the forest as the afternoon sun dips below the bluff-line. I begin the long drag up and out of the canyon, but I can’t get my mind off that old turtle staring at me from under her rock. There is something humbling about looking into the eyes of such a creature, knowing that she has seen more sunrises than you.

This article was originally published in the magazine of the Alabama Wildlife Federation, “Alabama Wildlife,” in January 2018. The Alabama Wildlife Federation (AWF) has kindly allowed the republishing of this article, and I encourage all who care about and enjoy the incredible wildlife of the Southeast’s most biodiverse state to join AWF and support their mission to protect and educate the public aboutAlabama’s wildlife
 
About the Author

Joseph Jenkins, born and raised in Alabama and has had a life-long passion for amphibians and reptiles and the outdoors. He is currently working on his M.S. in Biological Sciences at Auburn University and is advised by David Steen. His thesis explores aspects of the home range, movement patterns, and habitat selection of the flattened musk turtle.



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