Tennessee Wildlife Resources Agency

TWRA's Region 4 - East Tennessee

Reservoir Fisheries Management Program

Invasive/Exotic Species in Tennessee

Help limit the spread of invasive/exotic (non-native) species!

A number of non-native species are waiting to destroy Tennessee's aquatic ecosystems. Invasive plants, fish, crayfish, snails, mussels, or parasites can destroy existing aquatic communities when they enter a new river or reservoir. Many of these invaders have already entered our borders, so don’t help them get around.

All Anglers:

Bucket Biologist Beware Article pdf (99 k)


Didymo - Invasive algae found in TN tailwaters

Stream Anglers:

Rusty Crayfish pdf (242 k)

It is illegal to possess or transport live specimens of the following in Tennessee:

Bighead Carp pdf (816 k) Extremely prolific species of "Asian carp" that poses a significant threat to native ecosystems by disrupting the food chain. Can grow to four feet and may exceed 100 pounds. Immature bighead carp are easily misidentified as shad. (Poster)
Black Carp pdf (450 k) Also known as "snail carp" or "black amur" that poses a threat to native mussels.
Blueback Herring Releasing bait fish such as blueback herring can upset the balance of fish communities.
New Zealand Mud Snail pdf (99 k) This snail has become so abundant in some trout waters that they have displaced the native food supply for trout. Don’t let them ruin your trout streams, keep your waders clean!
Round Goby pdf (1,312 k) Competes with native, bottom dwelling fish such as sculpins and darters.
Rudd pdf (57 k) Disrupts spawning and nursery habitats of native species.
Ruffe pdf (215 k) Displaces native species and shown to reduce populations of yellow perch and emerald shiners.
Silver Carp pdf (609 k) This species of "Asian carp" is known for its explosive leaping abilities and poses a serious threat to boaters and aquatic communities. They have the potential to disrupt native food chains. Immature silver carp are easily misidentified as shad. (Silver Carp Video) (Poster) (Picture)
Snakeheads pdf (99 k) Popular aquarium trade species that can live several days out of water. A top level predator that can quickly impact native fish populations through predation or displacement. (Picture) (ID)
Swamp Eels pdf (78 k) Predator that eats a variety of animals including crayfish, frogs, and other fishes. Breathes air and in addition can achieve up to 25% of respiration through the skin.
Zebra Mussels pdf (1,060 k) These mussels have the potential to overwhelm aquatic communities and create costly problems for water supply and power projects. Help slow the spread of zebra mussels by following the boat cleaning guidelines.


For more information about the dangers of exotic species: http://www.protectyourwaters.net/

For more information about asian carp: http://asiancarp.us/