Two aquatic species found in the Edwards Aquifer, the San Antonio area’s primary source of drinking water, will not be listed as endangered under the Endangered Species Act, the U.S. Fish and Wildlife Service announced Tuesday.
The two species — the Texas troglobitic water slater and the mimic cavesnail — do not meet the standards required to be listed as endangered under the federal act, USFWS officials decided after a “thorough review of the best available scientific and commercial information.”
“After completing status reviews of the species and consulting with academia, state agencies, species experts and others, the Service concluded that neither species are in danger of extinction or likely to become in danger of extinction throughout all of their range or in any significant portion of their range and do not meet the definition of threatened or endangered species,” the USFWS stated in a press release.
Both species could still be threatened by environmental impacts, however, such as reductions in groundwater quantity and groundwater contamination, the agency added.
The mimic cavesnail is a small freshwater snail that lives deep within the Edwards Aquifer in Bexar County. The species is minute, measuring just 1 millimeter on average. The snail is a type of gastropod mollusk and has a single gill and a curly shell.
The Texas troglobitic water slater is a tiny, eyeless unpigmented groundwater crustacean that lives deep within the Edwards Aquifer. These small isopods range between 3 to 4 millimeters in length and feed on organic matter created by a unique strain of underground bacteria. They are mostly found in the Hays County region of the aquifer.
In 2007, WildEarth Guardians petitioned the USFWS to list the slater — and several hundred other species — as endangered. After several delays, USFWS found in 2009 that the water slater may be warranted for listing based on “presented substantial scientific or commercial information.” Since then, officials have been reviewing the species’ status.
The slater is one of 11 species covered by the Edwards Aquifer Habitat Conservation Plan, the habitat conservation plan managed by the Edwards Aquifer Authority. The conservation plan provides measures to minimize and mitigate harm to listed species, including maintaining sufficient spring flows to help them survive prolonged drought conditions. These measures also indirectly benefit the mimic cavesnail and other species that live in the aquifer.
“The determination to not list these species under the Endangered Species Act has no effect on the current status of the Edwards Aquifer Habitat Conservation Plan but does alleviate any concern that these species will need to be accounted for in any future iteration of an HCP for the Edwards Aquifer,” the Edwards Aquifer Authority said in a prepared statement.
The full status assessments for the two species can be found in the Environmental Conservation Online System.
The USFWS recently proposed adding two Edwards Aquifer cavefish species, the toothless blindcat and the widemouth blindcat, to the federal endangered species list.
