NASHVILLE, Tenn. (WKRN) — It’s important to get a check-up from the doctor – and that goes for animals too. U.S. Fish and Wildlife is kicking off its five-year review to see which species face extinction in Tennessee.

“We want to catch whatever ills there are in the system early when we can do something about it,” said Warren Stiles, listing and recovery biologist in Cookeville’s Tennessee Ecological Services Field Office for the U.S. Fish and Wildlife Service.

Stiles said that Tennessee wildlife is facing numerous threats, including invasive species and drought. But, top of the list is sediment.

According to Stiles, sediment invades creeks and streams and wreaks havoc on wildlife. “That fine silt and sediment can smother eggs, fill in gaps between rocks, clog gills on the fish, and bury mussels.”

Take the oyster mussel, which is currently endangered, and critical for the ecosystem. “They call them the livers of the rivers. They’re filter feeders. They’re filtering algae and bacteria and other nutrient matter in the river.”

Also hurt by sediment is the laurel dace fish, which is now only found in six streams. And because of invasive fish, the endangered Barrens topminnow is only found in a few spots in Middle Tennessee.

“Warren County, Coffee, Cannon, Grundy—areas around McMinnville, Tullahoma. Its main threat is mosquito fish.”

The Endangered Species Act requires these species to be studied every five years. Stiles is hopeful some can be taken off the endangered list once and for all.

“Tennessee has some of the highest fish diversity in the world for its area, certainly in the country. Every one of these species counts towards that.”

Stiles said he’s seen tremendous progress over the years too. A snail called the snail dugger is no longer endangered. He’s hopeful a small catfish called the smoky madtom will show improvement this year.