Snake River Spring Chinook Salmon Fishery Report, 2004

The Snake River recreational spring chinook fishery opened April 16 and was set to run through May 31, 2004. Two areas of the Snake River were open for the fishery in 2004. The first area was from the Texas Rapids boat launch upstream to the Corps of Engineers boat launch (approximately one mile) upstream of Little Goose Dam on the south bank of the river; referred to as the Little Goose (LGO) fishery in this report. The second fishery area was from the mouth of Wawawai Creek (approximately three miles) upstream of Lower Granite Dam to Red Wolf Bridge in Clarkston and will be called the Lower Granite (LGR) fishery in this report.

The preseason run estimate was for 57,800 spring Chinook at Lower Granite Dam with about 25% estimated to be of wild origin. Our estimated harvest target was 2,000 hatchery adult spring chinook, with an allowable Endangered Species Act (ESA) impact of 116 wild fish mortalities (0.2% ESA impact on wild Chinook estimated at Columbia River mouth). Assuming a 10% mortality rate on released fish, this allowed for 1,156 wild adult encounters. These fisheries were open seven days per week, with daily hours set from one hour before sunrise to one hour after sunset. The daily limit for the season consisted of two hatchery (adipose fin-clipped) spring chinook salmon (adult or jack) per day, with a minimum size of 12 inches. Anglers were required to use barbless hooks, with hooks of no more than 5/8 inch from point to shank. Inseason monitoring of spring chinook was used to reduce the estimated run size from 360,700 to approximately 200,000 fish. Estimates of harvest in lower river fisheries and the reduced run size prediction indicated the 2% ESA impact for non-tribal fisheries had been achieved, forcing the closure of the season on May 7, 2004.

The Washington Department of Fish and Wildlife monitored the fishery using a roving creel survey which included: boat ramp and shore interviews to collect catch rate, completed trip and biological information; and effort counts of shore anglers, boat anglers, and the number of boats (counts at least four times a day at LGO and at least three times a day at LGR). Monitoring was conducted at least one weekday and one weekend day per 7 day period, utilizing a dawn to dusk survey format. Creel surveys in both the LGO and LGR areas were conducted on 7 days (3 weekend days and 4 weekdays) of the season. The 22 day fisheries had 15 weekdays and 7 weekend days available (this included Friday April 16th as a weekend day, since it was opening day). We sampled 42% of weekend days and 27% of weekdays. Survey data were summarized weekly to assure compliance with the harvest target and ESA impact level that had been set for the fishery.