You never know what you may find swimming in the caves of North Alabama, including a species of crayfish that was once thought to be extinct. Well, that is what a University of Alabama in Huntsville professor found when he was snorkeling in Shelta Cave in Huntsville.
UAH professor Dr. Matthew L. Niemiller and his team found the Shelta Cave Crayfish, even though the species was listed as extinct for more than 30 years, and have recently released papers verifying the species.
What happened to the Shelta Cave Crayfish?
Dr. Niemiller’s team found individuals of the Shelta Cave Crayfish, known scientifically as Orconectes sheltae, in 2019 and 2020 excursions into Shelta Cave – its only home, which is a 2,500-foot cave system that’s owned and managed by the National Speleological Society and is unobtrusively located beneath the organization’s national headquarters in northwest Huntsville.
Dr. John Cooper, a biologist and speleologist who was a member of the NSS, studied the aquatic life in Shelta Cave with particular focus on crayfish for his dissertation work in the late 1960s and early 1970s. Shelta Cave’s aquatic ecosystem was particularly diverse then, with at least 12 cave-dependent species documented, including three cave crayfish species.
According to UAH, the aquatic ecosystem — including the Shelta Cave Crayfish — crashed sometime in the early 1970s. The crash may be related to a gate that was built to keep people out of the cave and yet still allow a grey bat maternity population to move freely in and out.
“The initial design of the gate was not bat friendly, and the bats ultimately vacated the cave system. Coupled with groundwater pollution and perhaps other stressors, that all may have led to a perfect storm resulting in the collapse of the aquatic cave ecosystem. To the best of our knowledge, only 115 individuals had been confirmed from 1963 through 1975. Since then, only three have been confirmed – one in 1988 and the two individuals we report in 2019 and 2020.”Dr. Matthew L. Niemiller, assistant professor of biological sciences at UAH
How it was discovered
The crayfish was rediscovered during an aquatic survey aimed toward documenting all life that was encountered in the cave system. While snorkeling in about 15 feet of water in North Lake located in the Jones Hall section of the cave, Dr. Niemiller spotted a smaller-sized cave crayfish below him.
While few crayfish are considered single-site endemics, in other words known to exist in just one location, which is somewhat more common in cave-dwelling species like the Shelta Cave Crayfish, Dr. Niemiller said.
Outside of the dissertation work done by Dr. Cooper, little about the life history and ecology of the species is known.
Dr. Niemiller is currently conducting the first-ever comprehensive assessment of groundwater biodiversity in the central and eastern United States, a pioneering search for new species and new understanding of the complex web of life that exists right under our feet. The research is funded by a five-year, $1.029 million National Science Foundation CAREER award.
He says knowing the health of populations of the tiny creatures that are dependent on groundwater is important.