CHATTANOOGA, Tenn. (CN) – Pointing to its battle against an evasive species and threats posed by climate change, the Fish and Wildlife Service on Friday extended Endangered Species Act protection to a small, colorful fish found only in a handful of Tennessee counties.
The Barrens topminnow, which grows to be about 3.75 inches long, lives primarily near the surface of springs and small streams in four counties in central Tennessee. According to FWS, the area where the species can be found has shrunk to just five locations, down from 18.
The primary reason for the decline of the Barrens topminnow has been the expansion of the invasive western mosquitofish, which preys on young Barrens topminnows and keeps them upstream when droughts descend on the habitat.
Humans introduced the western mosquitofish widely across the United States as a way to control mosquito larvae and thus tamp down the spread of malaria.
Once the western mosquitofish invade an area, the Barrens topminnow has three to five years before it meets local extinction, FWS said.
“All of the remaining populations of Barrens topminnow are at imminent risk of further expansion of western mosquitofish, as well as drought events, with no reasonable prospect of natural reestablishment once a population is extirpated,” according to the agency’s’ 17-page rule to be published Monday in the Federal Register. “Therefore, we conclude that the species is currently at risk of extinction throughout its range, thus meeting the definition of an endangered species.”
The FWS also said the Barrens topminnow will be increasingly sensitive to “extreme dry and wet years” that is expected to come with a changing climate. At one of the five sites where the fish swims, the spring has dried up three times since 2006. Each time, people captured the topminnows and returned them back to the wild after the drought passed.
The move to protect the Barrens topminnow under the Endangered Species Act was spurred by a lawsuit from the Center for Biological Diversity. One of its senior scientists, Tierra Curry, applauded the decision but called for more funding to protect other species.
“These beautiful fish are finally getting federal protection, but the decades of delay almost drove them extinct,” Curry said in a statement Friday. “It shows the steep cost of underfunding the Endangered Species Act. We’ve got to start protecting imperiled wildlife before recovery gets more difficult and expensive.”
Other groups such as the Tennessee Wildlife Resources Agency and universities in Tennessee have worked since 2001 to conserve the species.