MONTPELIER, Vt. (AP) — Signs will be posted near eight Vermont ponds where the use of baitfish is prohibited to protect native brook trout, the Vermont Fish and Wildlife Department said.

“Wild native brook trout thrive in ponds where there are simple fish communities with no or few other fish species,” department fisheries biologist Jud Kratzer said in a statement earlier this week. “Adding new fish species, even minnows, disrupts a long-established food chain. Trout populations suffer as a result.”

Brook trout are native to the eastern United States but no longer exist in much of their original range, the department said.

“Vermont boasts thousands of miles of cold, clean streams that provide excellent habitat for self-sustaining populations of wild brook trout, but only a few ponds in the state support wild brook trout,” Kratzer said.

Signs will be posted at public access points near Beaver Pond in Holland; Blake Pond in Sutton; Cow Mountain Pond in Granby; Jobs Pond in Westmore; Lewis Pond in Lewis; North Pond in Chittenden; Unknown Pond in Avery’s Gore; and Noyes Pond in Groton.