Visitors to the Umatilla National Wildlife Refuge can expect to see dead carp littering the pond at Whitcomb Island on the Columbia River for the next two to three months.
The U.S. Fish and Wildlife Service will be using rotenone, a chemical that only affects fish, to kill carp, starting Nov. 10. The chemical dissipates quickly, and the water will be safe for people, dogs and other wildlife, according to officials.
Carp eat aquatic vegetation and muddy the water to keep it from growing.
Fish and Wildlife has poisoned carp in other areas of the McNary and Umatilla National Wildlife Refuges in recent years. Numbers of waterfowl have dramatically increased as ducks, geese and swans again have a dependable supply of aquatic vegetation to eat.
“The increase in waterfowl use at those sites has been even better than we hoped,” said Lamont Glass, manager of the Umatilla refuge, in a statement. “Before treatment, waterfowl were almost entirely absent.”
In the near term, visitors to the Whitcomb Island area should see large numbers of fish-eating birds — which could include bald eagles — show up to feast on the dead carp, said Denise McInturff, visitor services specialist for regional refuges.
Whitcomb Island is about eight miles west of Paterson.