KALISPELL (AP) – Hybrid trout in two lakes west of Hungry Horse Reservoir have been poisoned to make room for pure westslope cutthroat trout, state Fish, Wildlife and Parks officials said Friday.
Fisheries crews completed the poisoning on Black Lake on Sept. 28 and on the smaller Blackfoot Lake on Monday.
Crews used an air tanker to drop 1,260 gallons of rotenone in three drops into Black Lake while another 210 gallons was sprayed from a boat. Small tributaries were also treated.
Trout from fingerling size up to 18 inches began dying almost immediately. The majority sank to the bottom of the lake.
Crews applied 65 gallons of rotenone to Black Lake by boat.
Next spring, westslope cutthroat trout will be stocked in the lakes.
The long-range plan is to poison hybrid trout and restock westslope cutthroats in two lakes in the area each year over the next nine years.