Tennessee Teams Release 131 Endangered Topminnows and Rescue 232 From Drought

Conservation teams released 131 federally endangered Barrens topminnows from Tennessee’s Hickory Creek population back into the wild this month. On the same day, biologists rescued 232 wild topminnows from a shrinking pool at a separate site, the U.S. Fish and Wildlife Service reported Nov. 9. The release and the rescue involved different groups of fish.

The release followed earlier work to protect fish from drought. Biologists monitored sites where the species still lived and moved fish to safety as water levels fell. Some adults were kept for breeding, while others were moved to facilities where they could grow until conditions were suitable for release. Conservation Fisheries, Inc. led breeding work, and Wolf Creek and Dale Hollow national fish hatcheries provided space for fish in the recovery effort.

The 131 fish released from Wolf Creek National Fish Hatchery carried small color tags under their skin. The tags identify groups by details such as when they were released. If biologists catch tagged fish during future surveys, they can tell which group those fish came from.

At the separate rescue site, a prolonged dry spell had cut the pool off from the spring that fed it. Biologists collected the fish with a net and sent 40 adults to Conservation Fisheries, Inc. for its breeding program. Another 145 adults and 47 juveniles went to Wolf Creek National Fish Hatchery for care until habitat conditions improve.

Why This Matters for Animals

The Barrens topminnow occurs naturally only in Middle Tennessee. It lives in springs and spring-fed streams, so a drying pool can put an entire local group at risk. The species was listed as endangered in 2019. Habitat loss and pollution contributed to its decline, along with the introduction of western mosquitofish, which prey on topminnow eggs.

Moving fish out of the shrinking pool addressed an immediate threat. Releasing the tagged Hickory Creek fish addressed a different question: whether fish raised in human care can survive after returning to the wild. The release count records how many went back. Future surveys can help show how they fare.

The accompanying AI-generated illustration depicts a fictional Barrens topminnow in an imagined creek.

Source: U.S. Fish and Wildlife Service — November 9 release and rescue report