DWR reminding public 'don't ditch a fish' after discovering fish illegally introduced into 3 waterbodies in 2024

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

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

• Yellow perch in Palisade State Park in May
• Goldfish at Cove Pond in June
• Utah chub in Millsite Reservoir in April

The DWR also confirmed additional growth and reproduction of fish illegally introduced in two reservoirs last year: smallmouth bass in Settlement Canyon Reservoir and green sunfish in Yearns Reservoir. Biologists are also continuing to monitor Strawberry Reservoir after an illegally introduced walleye was caught there last December.

"Thankfully, we have still not verified the presence of any additional walleye at Strawberry Reservoir since the one fish was caught last year," DWR Fisheries Biologist Alan Ward said. "We have employed netting, electroshocking, angler reporting, stream surveys and environmental DNA sampling to look for additional fish, and more efforts will be made in the coming year to further look for their presence. We are hopeful that this illegally introduced fish won't spread or impact the fishery."

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 or outcompete other fish species, including sportfish, native fish and endangered fish species. Biologists in southeastern Utah are especially concerned about the Utah chub introduction into Millsite as this population cannot be controlled using conventional methods, due to native species in the drainage. These Utah chub will now freely compete with sportfish in the fishery that were not harming the native fish there.
• 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 Trina Hedrick said. "It is also illegal in Utah to transport live fish or to introduce them into a new location 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.

"Before we stock fish into a waterbody, we go through extensive processes to conduct risk assessments to native species, perform disease testing, evaluate the compatibility of the new species with existing sportfish and assess angler preferences for that fishery," Hedrick said. "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. 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 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.