Invasive species: Popular aquarium sunfish found in NH waters 

The state’s Fish and Game Department has identified the presence of a popular aquarium fish in the Piscataquog River and Waukewan Lake.

This year’s discovery of the non-native, invasive green sunfish comes after biologists found the species in the Little Sugar River in Charlestown last year. It’s a concern, says Fish and Game, because green sunfish compete for habitat and food with New Hampshire’s native sunfish.

Green sunfish can be found in a variety of habitats in all 48 contiguous states, though their native range is the central U.S. east of the Rocky Mountains. They’re also a popular aquarium fish, and Fish and Game suspects that’s how they made their way into New Hampshire waters. 

“Help us protect New Hampshire’s natural resources by not releasing any aquarium fish into the natural environment — it’s illegal and a threat to a variety of native wildlife,” Fish and Game said in a release.

The large mouths of green sunfish enable them to consume a wider variety of prey than native pumpkinseed or redbreast sunfish, an advantage that may allow them to out-compete native species for food. 

Fish and Game urges people who suspect they’ve caught a green sunfish not to release it. Instead, the department says, “humanely terminate the fish,” preserve its coloration and identifying characteristics, take a photo, record the location, and email findings to [email protected].

The department provides a fact sheet on what to do with unwanted aquarium fish.