The Snake River was open
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 fishery was open seven days per week,
with daily fishing hours set from one hour before sunrise to one hour
after sunset. The daily limit consisted of one hatchery (adipose fin-clipped)
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 that 5/8 inch from point to shank.
The pre-season Snake River
runsize estimate (entering the mouth of the Columbia River) was 128,100
spring/summer Chinook with about 23,400 (18%) estimated to be of wild
origin. Preseason plans for the Snake River recreational chinook fishery
was to harvest up to 2,132 hatchery adult spring chinook, with an
allowable Endangered Species Act (ESA) impact of 47 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 468
wild adult encounters. ESA impacts for this fishery are included as
part of the non-Indian rate of 2.0% allowable impact which also includes
recreational and commercial fisheries downstream. However, the run
came in at a lower rate than expected from pre-season estimates. An
in-season estimate in early June based primarily on counts at Bonneville
Dam reduced the estimated Snake River spring/summer chinook run to
approximately 39,700 fish (at Lower Granite Dam). We reduced the harvest
target to 373 hatchery chinook adults and the encounter (or “handle”)
of wild chinook adults to 124. Total ESA impact for this fishery was
expected to be 12 wild adult mortalities or an impact rate of approximately
0.17%.
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 were done 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 7 days (3 weekend days and 4 weekdays)
of the season. The 20 day fishery had 14 weekdays and 6 weekend days
available. We sampled 50% of weekend days and 28.6% of weekdays. Survey
data were summarized weekly to estimate kept catch and encounters
(kept catch and fish released) and assure compliance with the ESA
impact level that had been set for the fishery.
The fishery results were
divided by “spill” and “no spill” segments.
The no spill days were from June 11th through the 19th and also included
June 30th. No spill days had much better fish movement through Little
Goose Dam and therefore had better catch and release rates than spill
days. June 30th was included as a no spill day because the proportion
of spill to turbine flows was modified on that day and most of the
fish that were pooled up below the dam passed on that day (Appendix
A). We have also heard that the catch rate increased on the afternoon
of the 30th although a creel survey was not conducted on that day.
The major spill days were from June 20th through June 29th. During
spill days the harvest and release rates were very poor, and fish
passage at Little Goose Dam was very low (Appendix A).
