Drawdown planned for McArthur Lake wildlife area

McArthur Lake, a shallow reservoir between Sandpoint and Bonners Ferry managed by Fish and Game, will undergo a summer-long drawdown beginning June 1. The lake level will be dropped as low as possible over the course of four to six weeks and remain at that level throughout summer, which will render the fishing dock and boat ramp unusable until it’s refilled.

Water will continue to flow through McArthur Lake’s relic channels of Deep and Dodge Creeks and provide habitat for fish and wildlife during the drawdown. Refill will begin in early fall and is expected to be completed during 2020 spring runoff.

This property is used by hunters, anglers, fur trappers, as well as birdwatchers, hikers and naturalists.

Fish and Game’s top management priorities for McArthur Lake include maintaining habitat for waterfowl, upland game and big game.

The goal of the drawdown is to continue to provide a healthy wetland ecosystem to benefit wildlife, particularly waterfowl. Habitat and water levels at McArthur Lake are managed to provide forage and security cover for migrating waterfowl, as well as nesting cover for locally breeding ducks and geese.

To maintain and improve habitat, managers must draw down the lake every five to 10 years. The last complete drawdown at McArthur Lake was in 2012, preceded by a partial drawdown and dam repairs in 2006, and a complete drawdown in 2002.

Periodic drawdown is designed to mimic natural wetland cycles. Once these long-flooded soils are exposed and dried, Fish and Game staff works to increase soil aeration, stimulate native seed growth, reduce overstocked cattails and contain noxious weeds.

Plant and wildlife communities in the reservoir have improved following previous drawdowns, and gradually exposed mudflats provided foraging areas for great blue herons, bald eagles, killdeer, lesser yellowlegs and multiple species of sandpipers.

Highly productive wetland plants such as smartweeds, sedges and rushes responded to the receding water levels through the summer months, typically producing more than a ton of seeds per acre, which provides food for a variety of waterfowl.

In addition to more seeds produced, varied flower timing is valuable for pollinator insects, and aquatic plants provide habitat for a variety of invertebrates, including protein-rich insects, worms, crustaceans and mollusks that provide important food sources for waterfowl and fish.

By managing water levels and connections between tributaries, fish can move into Deep Creek, Dodge Creek and relic pools and channels within the wetland during the drawdown. Some fish loss is expected, but fish repopulated the lake without restocking after previous drawdowns.

While McArthur Lake is drawn down, anglers can check out other nearby fishing spots, including: the Pack River Delta of Lake Pend Oreille, Cocolalla Lake, Smith Lake, Bonner Lake, Jewel Lake, Brush Lake, and Dawson Lake.

To learn more about these locations, and see other fishing options, go to the online Fishing Planner at idfg.idaho.gov/ifwis/fishingplanner.

McArthur Lake Wildlife Management Area is one of Fish and Game’s oldest management areas in the state. The land was purchased and has been managed primarily for waterfowl habitat since its establishment in 1942.

For questions regarding the drawdown, please contact Panhandle Regional Habitat Manager Norm Merz at 208-769-1414.

Evan DeHamer is a regional wildlife habitat biologist for Idaho Fish & Game in the Panhandle Region.