OLYMPIA, Wash. (AP) - A smaller-than-expected return of chinook salmon has prompted regulators to close chinook fishing at the end of the day Sunday on sections of the Snake and mid-Columbia rivers.

In addition, almost all recreational salmon fishing has been closed on rivers throughout California, and a chinook closure was ordered on the lower Willamette River in Oregon.

Chinook, also known as kings, are the biggest and most prized of the Pacific salmon species.

The Snake and Columbia fisheries had been scheduled to remain open through mid-June, but returns of spring chinook have fallen short of expectations and action was needed to save protected fish runs, said Cindy LeFleur, Columbia River harvest manager for the Washington state Department of Fish and Wildlife.

The current forecast is for 180,000 returning chinook, down from 269,300 initially projected by Washington and Oregon fishery managers.

"This is an unfortunate situation," LeFleur said. "Many of these fisheries were just getting started, but an updated run forecast indicates we need to take action on these spring chinook fisheries."

Columbia River treaty tribes also agreed to close their mainstem spring chinook fisheries on Sunday, the state agency reported in a news release.

Areas covered by the early closures include:

-The Columbia near the Ringold Springs hatchery in Franklin County.

-The Snake from the railroad bridge at confluence with the Columbia upstream to the no-fishing zone below Ice Harbor Dam.

-The Snake from the Texas Rapids boat launch upstream seven miles to the boat launch about a mile upriver from Little Goose Dam.

Sport and commercial fisheries below Bonneville Dam on the Columbia have been closed since mid-April, and the recreational fishery between Bonneville and McNary dams is scheduled to close at the end of Saturday.

On the flip side, a chinook salmon season opens Thursday on the Icicle River in Chelan County in central Washington and will run through July 31, fishery managers announced Friday. More than enough fish are expected to return to meet the needs of the Leavenworth National Fish Hatchery, according to the state agency.

In Oregon, state regulators banned spring chinook fishing on the Willamette River below Willamette Falls, effective Monday. Chinook can still be taken above the falls and in the Clackamas River.

The California Fish and Game Commission voted Friday to ban almost all recreational salmon fishing in that state's rivers this year to protect declining chinook stocks. Limited fishing will be allowed on part of the Sacramento River in November and December, the panel decided.

The federal government previously closed the California coast and most of the Oregon coast to both recreational and commercial salmon fishing because of the chinook shortage.