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The Georgia blind salamander could be an indicator species for the health of the Floridan aquifer, but scientists don’t know if it’s thriving or declining BY BETSY L. HOWELL – NOVEMBER 29, 2016 “Every biologist thinks his or her species of interest is the canary in the coal mine,” says John Jensen, state herpetolo- gist for the Georgia Department of Natural Resources. “But the Georgia blind salamander, in my opinion, really fi ts this anal- ogy better than most.” Jensen, who has worked with the spe- cies for two decades, explains Photo by Jake Scott - The Georgia blind salamander’s his reasoning by pointing out the subterranean habitat makes it diffi cult to study. As a result, salamander’s habitat: aquifers. very little is known about the species. “It lives in the groundwater — groundwater that we rely on for “stygobitic” species — that is, species that live in ground- drinking. If we are seeing de- water systems or aquifers, — are some of the most diffi cult clines or disappearances of blind species on earth to fi nd. Scientists know they inhabit the salamanders, then we should be Floridan aquifer, a vast, subterranean network of limestone very alarmed.” passageways that underlies much of the southeastern Unit- ed States, yet information on specifi c locations of salaman- Yet to know if these salamanders ders is hard to obtain. Some parts of this network permit are declining or disappearing, erect walking by humans, while many areas can only be it’s fi rst critical to know where accessed by crawling through “worm holes” — tight pas- they are, or are not, living in the sages barely large enough for an adult body. Water-fi lled aquifer. Georgia blind salaman- rooms and tunnels can only be navigated by scuba diving. ders, along with other The underworld hazards to surveyors are many and varied. There is the potential for getting lost or stuck, When she did move, it was by using her running out of air or encountering bad air limbs, but also by fi shlike movements from (generally a result of carbon dioxide buildup her body and tail. Vibrations in the room from from the decomposition of organic matter), or sounds or activity sent the animal dashing breathing air fl ecked with the fungal spores wildly about the aquarium. that cause histoplasmosis, an infection that can cause fever, coughing, and fatigue. One week after the salamander had been col- lected, a fall from the x-ray table killed her “Very little is known about this species,” before more could be learned and observed Jensen admits, “beyond their general habitat and before her young were born. From this and morphology. I have only seen blind sala- discovery, however, came the Latin name for manders in Climax Caverns [in southwest the genus of the Georgia blind salamander, Georgia] and those pools took hours of caving “Haideotriton,” or “salamander of the lower to reach. The animals were in water directly regions.” below a southeastern myotis bat roost. The bats had contributed guano to the bottom of In April 2010, the Center for Biological Di- the pool, and this dark substrate really helped versity (CBD) petitioned the US Fish & Wild- make the translucent salamanders visible.” life Service (USFWS) to list Haideotriton wallacei under the Endangered Species Act. Georgia blind salamanders fi rst became The Center cited two primary threats to the known to science in May 1939. That spring, species: Habitat loss from water pollution and one individual was brought up in a water water level fl uctuation as a result of draw- sample from a 200-foot well in Albany, Geor- down of the aquifer for human uses. In 2011, gia. This female salamander had eggs visible the USFWS published a fi nding that CBD’s in her sheer belly, measured just three inches petition presented “substantial scientifi c or long, and did not have eyes. With transpar- commercial information indicating that list- ent limbs and body, tiny dark spots speckled ing [of the Georgia blind salamander] may throughout, and long, delicate, blood-red gills, be warranted.” This fi nding meant that the the animal might have crawled out of the federal agency would begin a status review to pages of a fairy tale. Or come from another determine if the species should be listed. That planet. Living in a world of darkness makes review is still being assembled. sight and coloration unimportant, while the feathery gills help to capture oxygen in slow- The lack of understanding of the blind sala- moving water. Such characteristics make this mander’s distribution is a concern when trying species unlike almost all other salamanders. to determine the level of threat to the spe- cies. As Jensen points out, “Although these The blind salamander remained alive in cap- salamanders may occur in aquifers well away tivity for one week. Unmotivated to eat any from accessible caves, their densities may not food offered, she stayed motionless most of be as great due to the lack of organic matter.” the time on the bottom of the aquarium where However, no one knows for sure, a fact that she was housed. makes effective conservation extremely dif- fi cult. photo by Alan Cressler - The USFWS is conducting a status review to determine whether the Georgia blind salamander should be listed under the ESA. With the petition from CBD came a wave The second strategy involves the remarkable of interest among Florida and Georgia state new technology of environmental DNA col- wildlife agencies to determine the blind sala- lection. All living organisms are constantly mander’s status. The question was how does shedding hair and skin and if these bits can one go about fi nding a species that inhabits be collected, then matched with reference such a challenging environment? The answers DNA obtained directly from other individu- can be found in plastic bottles, environmental als of a species, confi rmation of presence DNA, and cave divers. can be established. The challenges with this method are that one, a species must live in The fi rst method employs plastic soda bottles, great enough densities to increase the amount weighted and sunk into the aquifer through of body material available for collection, monitoring wells. The bottles, which are and two, the collection point needs to be checked daily, are baited with cashews and downstream from the animals. If a species is shrimp to entice the salamanders. This meth- present in an area, but in low numbers and od has captured Texas blind salamanders, upstream from where water is sampled, the however, it took 200 to 300 hours of trapping results will be erroneously negative. Georgia time to catch two individuals from that spe- blind salamanders have yet to be documented cies, so fast results are generally not to be had with environmental DNA analysis, though with this survey technique. A recent study water samples have been taken from wells done in 2014-2015 involved setting traps in and springs at numerous locations. 18 wells in 10 Georgia counties. Though no blind salamanders were caught, 32 Dougherty Because of the limitations inherent with Plain cave crayfi sh, another species of con- these inventory methods, most of the docu- cern, came in for the nut and shrimp baits. mentation of the species has come from visual observations. People swimming and squeezing their way “Five minutes being stuck,” says Bryant, into these serpentine caves and passageways “doesn’t sound like much, but when you’re and taking photographs have confi rmed the 155’ deep and have no visibility trying to get blind salamander at 36 locations in Georgia through a tight place, you can use a lot of air.” and northern Florida. Scientists play a role in this work, but so do cave divers, a small This, then, is the world of the Georgia blind and passionate subset of the greater technical salamander, as well as other stygobitic spe- diving community. “They’re not biologists,” cies, such as the Dougherty Plain blind cray- says John Jensen, “but they really enjoy hav- fi sh, the freshwater eel, and the Florida chub. ing a conservation excuse for doing what Each cave, according to Bryant, with its they love.” In terms of knowing more about unique geology and shape, has its own per- the blind salamanders, it is fortunate they do. sonality. The type of limestone in the cave, Cave divers face similar dangers that regular hard or soft, and the amount of impurities, cavers face, and also have to contend with including tannins, provides different color- silt, a limited air supply, and even alligators ation for each cave, while the thickness of the resting at cave entrances. But for the few in- limestone can determine whether a cave sys- volved in this sport, the rewards are many and tem becomes deep or stays shallow. The water the privileges of exploring and conserving current inside a cave can make swimming cave habitats and cave wildlife far outweigh hard or easy and plays a role in how much silt the hazards. forms on the bottom. Regarding “tight spots,” Bryant says modestly, “Sometimes I’ve had Guy Bryant, a retired pharmacist and com- to remove my tanks and push them in front of puter programmer from Valdosta, Georgia, me to fi t through.” has been cave diving for 44 years. He can’t remember a time in his life when he wasn’t Bryant has seen Georgia blind salamanders in interested in caves. “Before I began scuba two cave systems: Radium Springs, the larg- diving,” he says, “I was exploring dry caves, est natural spring in Georgia, and Hole in the so it was natural that I would incorporate Wall Spring, an electrifying blue water world underwater caves into my activities.” Bryant’s in northern Florida.

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