MISSOULA (AP) -- Efforts are underway to rebuild the brook trout fishery in Georgetown Lake, which supported a self-sustaining population of the popular fish since 1915 before whirling disease hit.

The Montana Fish, Wildlife and Parks wants to stock 50,000 of the young trout in the lake annually until the fishery is restored to historic numbers.

The public has until Jan. 22 to comment on the proposed hatchery stocking.

In recent years, whirling disease has cut into the fishery, and a 2003 census turned up no brook trout.

''By stocking brook trout that are free of infection and large enough to avoid getting infected, we expect that stocked fish will survive better than wild fish," said fisheries biologists Pat Saffel and Wayne Hadley, authors of the environmental assessment.

The goal, they said, is to return brook trout to large enough numbers that they again represent 10 percent to 15 percent of the trout caught in the January ice fishery.

The agency's plan would deliver 50,000 brook trout, 2-4 inches in length, to the lake near Anaconda each year, with annual reductions of that number as the population recovers. The hatchery fish would be marked.

A major concern, the biologists said, is the potential impact of any stocking on native bull trout and cutthroat trout, but they expect none because neither species currently exists in the lake.

However, both species are found in Flint Creek, some 20 or more miles below the reservoir.

Saffel and Hadley said the lake's stocking probably would not change the population size or distribution of brook trout in the Flint Creek drainage ''since they have been present for almost 100 years."