Elevated water temperatures and low flows in the St. Regis River, west of Missoula, have prompted Montana Fish, Wildlife and Parks (FWP) to request that anglers voluntarily limit all fishing to morning-only, until conditions improve. The request takes effect on Friday, July 27.
Low flows combined with high water temperatures stress fish by concentrating them and reducing the amount of oxygen in the water. Angling can add additional stress on native bull and cutthroat trout and other species.
By limiting fishing to morning-only, caught-and -released fish will have better survival rate because water temperatures are cooler in the morning.
FWP fishery biologist Ladd Knotek, Missoula, requested the voluntary restriction because water temperatures have been above 65 degrees. "It's the first step in our department's Drought Contingency Plan to protect fisheries that are threatened by continuing drought conditions" according to Knotek. That plan calls for voluntary restrictions on bull trout streams when maximum daily water temperatures equal or exceed 60 degrees for three consecutive days and on other trout streams when maximum daily water temperatures exceed 73 degrees for three consecutive days. The preferred water temperature for bull trout is 50-55 degrees and for rainbow trout in 55-57 degrees; temperatures of 77 degrees or more can be lethal to trout.
The plan has three stages for protecting fish in streams severely impacted by drought: a voluntary request to anglers to only fish in the mornings; a mandatory restriction allowing fishing only from midnight to noon; and a full closure prohibiting all fishing.
Stream flows and water temperatures on the St. Regis and other streams and rivers will be monitored and, based on the plan's criteria, evaluated to determine if restrictions are needed.