NASHVILLE, Tenn.— In response to decades of advocacy from the Center for Biological Diversity, the U.S. Fish and Wildlife Service today proposed to protect critical habitat for the endangered Barrens topminnow, an iridescent green fish from central Tennessee. The proposal includes 1.5 acres of spring pools and 11.4 miles of flowing springs in Cannon, Coffee, Dekalb, Franklin, Grundy and Warren counties.

“All wildlife are important, so it’s a relief that the springs where these stunning fish swim will at long last gain protection,” said Tierra Curry, endangered species co-director at the Center. “The tale of this little fish, who’s waited nearly five decades for protection, highlights why we need a comprehensive federal plan to protect imperiled wildlife that keeps pace with the urgency of the extinction crisis.”

The Barrens topminnow was proposed for Endangered Species Act protection with critical habitat in 1977, but the proposal was never finalized. In 1982 it was moved to a waiting list for federal protection. The Center filed a scientific and legal petition with the Service to protect the fish in 2010 and it was finally protected as endangered in 2019. A 2023 lawsuit led to today’s proposal to protect the fish’s essential habitat.

Critical habitat designation is an additional layer of protection for endangered animals and plants that requires the Service to review any federally funded or permitted activities to make sure the places they live aren’t harmed. The habitat protection for Barrens topminnows should be finalized by July 2025.

Barrens topminnows only live in clear cold streams where the predominant source of base flow is groundwater. The fish grow to 4 inches long, have flashy coloration, and swim near the surface where they prey on mosquito larvae and other insects.

The topminnow is threatened by invasive mosquitofish, droughts and severe floods, and livestock intrusion into springs. Once known to live at 18 sites, the fish survive at only six sites. One of the topminnow’s springs has dried up three times since 2006, and fish were rescued by scientists and held until water flows resumed.

To make sure Barrens topminnows are safeguarded from extinction, captive-breeding populations are held at Conservation Fisheries Inc. in Knoxville and at the Tennessee Aquarium Conservation Institute in Chattanooga.

The topminnow’s range includes headwater streams in the Duck and Elk river watersheds, which are part of the Tennessee River drainage, and the Caney Fork watershed in the Cumberland River drainage.