Snake River Spring Chinook Salmon Fishery Report, 2003

The Snake River recreational spring chinook fishery opened April 26 through May 31, and was then extended through June 15, 2003. The area opened for fishing 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. The preseason estimated harvest target of 700 hatchery adult spring chinook was set, with an allowable Endangered Species Act (ESA) impact set at 75 wild fish mortalities. Assuming a 10% mortality rate on released fish, this allowed for 750 wild adult encounters. Fishing was opened for a seven day per week fishery, with daily hours set from one hour before sunrise to one hour after sunset. The daily limit for the original season consisted of one hatchery (adipose fin-clipped) spring chinook salmon (adult or jack) per day, with a minimum size of 12 inches. In-season tracking of the upriver spring chinook return and estimates of harvest in lower river fisheries indicated a larger than predicted return, allowing for an extension of the originally adopted season. During the extension from June 1 to June 15, the daily limit was increased to two hatchery fish per day, with a minimum size of 12 inches. Anglers were required to use barbless hooks, with no more than 5/8 inch from point to shank throughout the fishery.

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 and boat anglers and the number of boats (counts at least five times a day). Monitoring was conducted at least one weekday and one weekend day per 7 day period, utilizing a dawn to dusk survey format. Creel surveys were conducted on 20 days (8 weekend days and 12 weekdays) of the season. Of the 51 day season, 34 weekdays and 17 weekend days were available (this included Monday May 26th as a weekend day, since it was a holiday). This gave us a sample rate of 47 % of weekend days and 35% of weekdays. Survey data was summarized weekly to assure compliance with the harvest target and ESA impact level that had been set for the fishery.

Interviews were conducted with 2,298 anglers with a total of 6,374.67 hours of fishing effort, but only 2,119 of these anglers were targeting spring chinook (5,854.44 angler hours). Other anglers interviewed were targeting catfish, smallmouth bass, sturgeon, and northern pikeminnow. Data collected during the creel surveys was entered into a spreadsheet that was used to calculate angler hours, total fish harvested, catch rate (hours/fish harvested and hours/fish caught), total fish released, release rate (hours/fish released), and fish size (min, max, and mean) (Table 1).