SAN ANTONIO – Two cave-dwelling catfish species from the San Antonio area might be added to the endangered species list after federal officials say too much water is being pumped out of the Edwards Aquifer.
USFWS officials said findings indicate that both of the ‘blindcats’ are in danger of extinction throughout their range due to mortality from uptake by groundwater wells, according to a press release.
“The toothless and widemouth blindcats are among the rarest fish species in the world and are found at the greatest subterranean depths known for cavefish, at over 1,000 feet below the City of San Antonio in the Edwards Aquifer,” said Supervisory Fish and Wildlife Biologist for the Austin Ecological Services Field Office Michael Warriner.
The blindcats were first discovered in the early 1900s and are among the smallest catfish species in Texas.
Like other cave-adapted animals, they lack pigment and developed eyes and inhabit a very deep and little-studied region of the aquifer that is inaccessible to humans, USFWS officials said.
“While the great depth of their habitat protects them from many human-caused threats, thousands of these fishes were likely lost over the last one hundred or more years as groundwater pumping activity increased across Bexar County,” said Warriner.
KSAT reached out to the Edwards Aquifer Authority and receive the following statement from EAA General Manager Roland Ruiz:
“We believe that to list these two species now is premature. The best available science regarding the distribution, status and potential protection of both the toothless blindcat and the widemouth blindcat is extremely limited and, in our opinion, needs further study prior to determining whether listing them is appropriate. We look forward to availing ourselves of the US Fish and Wildlife Service’s public comment process to share our perspective.”
USFWS officials allege that while groundwater pumping has directly resulted in the death of the blindcats, groundwater quantity and quality in areas of the aquifer that support the fish’s habitat has not experienced a substantial change from historical conditions.
The San Antonio portion of the Edwards Aquifer supports a wide array of aquatic species, including seven species listed under the ESA:
- Fountain darter
- Texas blind salamander
- San Marcos salamander
- Texas wild-rice
- Comal Springs riffle beetle
- Comal Springs dryopid beetle
- Peck’s Cave amphipod
These species inhabit the Comal and San Marcos Springs Systems of central Texas and derive their flow from the Edwards Aquifer, according to the USFWS.
“We recognize that water resources are incredibly important for local communities, landowners, businesses, municipalities and visitors,” said Karen Myers, Field Supervisor at the Austin Ecological Services Field Office. “We look forward to continuing to work collaboratively with the Edwards Aquifer Authority and other local organizations to conserve and protect the Edwards Aquifer for the benefit of people and wildlife.”
The widemouth blindcat was last collected from a well in 1984, while the toothless blindcat has been collected in small numbers from a single well as recently as 2022, according to the USFWS.
Comments are invited on the proposed rule to list these species as endangered on the Federal Register. Comments will be accepted until Oct. 23.