DWR reminding public 'don't ditch a fish' after discovering fish illegally introduced into 4 waterbodies in 2023

Salt Lake City — After several recent illegal introductions, the Utah Division of Wildlife Resources is reminding Utahns that it's both harmful and illegal to dump unwanted pet fish into local ponds or to move fish you've caught from one waterbody to another.

Each spring and fall, DWR biologists across the state survey various lakes and streams to get data about the fish in those waterbodies, including weight, condition and population numbers. However, this year, biologists discovered several fish that were illegally placed into several waterbodies across Utah, including:

• Green sunfish at Yearns Reservoir in Sanpete County
• Smallmouth bass in Settlement Canyon Reservoir in Tooele County
• Redside shiners in Paragonah Reservoir in Iron County
• Largemouth bass in Newcastle Reservoir in Iron County

When a fish is illegally introduced into a pond, stream or lake, it can have several negative effects on that fishery, including:

• Illegal fish species can prey on and outcompete other fish species, including sportfish, native fish and endangered fish species.
• The new fish can introduce disease because they weren't properly tested before being dumped into that waterbody.
• The new fish can negatively impact water quality.

"Illegal fish introductions seldom improve fisheries — instead, illegal introductions typically ruin fisheries and threaten the species that live there," DWR Sportfish Coordinator Randy Oplinger said. "It is also illegal in Utah and can result in a class A misdemeanor."

While it's illegal to dump unwanted aquarium fish into a waterbody, it's also illegal to move live fish from one waterbody to another or to take them home. Anglers often think that when they move fish from one waterbody to another that they are introducing a species that will help improve the fishing at a pond, stream or lake. This is seldom true, and instead, these illegal introductions often ruin a fishery.

"It is very expensive and takes a very long time — often requiring rotenone treatments that kill all the fish — to restore these waterbodies after fish have been illegally introduced," Oplinger said. "Please help our native fish species and maintain quality fishing in Utah by never dumping a fish or being a 'bucket biologist.'"

Utahns are encouraged to call 1-800-662-3337 to report any invasive fish they find, or if they see anyone illegally introducing fish into a waterbody or trying to relocate live fish. Utahns can also contact their nearest DWR office if they have an unwanted fish or if they have concerns about a fishery in Utah.

Learn more about the negative consequences of illegal fish introductions by visiting the "Don't Ditch a Fish" page on the DWR website.