BOISE, Idaho — Chinook salmon fishing in the Clearwater River basin is closed due to lower-than-expected returns of adult Chinook.

The Idaho Department of Fish and Game says the closure will remain in effect May 18-19.

The closure is for the Clearwater River, the North Fork, South Fork, and Middle Fork of the Clearwater River.

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Biologists say they will reassess the fishery later this month. If more fish return, the fishing season may reopen. Right now, there's some uncertainty about the actual size of the run.

By May 22, over 80 percent of the Chinook salmon destined for the Clearwater River basin should have passed over Bonneville Dam on the Columbia River, and managers will have a better idea if the Chinook return will be large enough to allow for more fishing.

Currently, the number of fish returning to Rapid River Hatchery is projected to be high enough for the fisheries to remain open in the lower Salmon River and Little Salmon River.