BISMARCK, N.D. (AP) — The North Dakota Game and Fish Department says the invasive silver carp population is holding steady in the state and doesn’t appear to be growing.

The leaping fish was first detected in North Dakota in the James River in 2011, moving upstream from South Dakota when water levels were high during record summer flooding.

Invasive Species Coordinator Jessica Howell tells KFGO silver carp are surviving in North Dakota, but don’t appear to be reproducing. The carp are considered a significant threat to local aquatic species because they attack the food chain and the leaping fish have been known to injure boaters.