Nine nights of gillnetting in the lower Columbia River between Warrior Rock and Beacon Rock will begin Aug. 7. The commercial fleet will fish Sundays, Tuesdays and Thursdays from 9 p.m. to 6 a.m. through Aug. 26, according to regulations adopted today in Vancouver by the Columbia River Compact. Nine-inch-minimum-mesh nets will be required. Robin Ehlke, assistant Columbia River policy coordinator for the Washington Department of Fish and Wildlife, said the netters are projected to catch 2,200 fall chinook in the first week, 7,500 in the second week and 19,700 in the third week. The 9-inch-mesh nets are expected to reduce the handle of steelhead and sublegal sturgeon.