Salmon Spawning Escapement Surveys in North Hood Canal

In 2006-07 tribal staff and volunteers conducted foot surveys on index reaches using the standard procedures established by Washington Department of Fish and Wildlife, to count either live or dead adult salmon and redds. Numbers of spawning salmon were counted every one to two weeks on standard stream sections between August 15 and December 30. The surveys were initiated in August to include the early return timing for summer chum. Supplemental surveys were conducted on additional stream reaches several times during the season to obtain a better understanding of the distribution of spawning salmon in the monitored watersheds. Surveys were conducted on 12 streams: Gamble Creek, Harding Creek, Spring Creek, Middle Creek, Martha-John Creek, Miller Lake Creek, Cougar-Kinman Creek, Thorndyke Creek, Stavis Creek, Little Anderson Creek, Thomas Creek and Seabeck Creek. WDFW and the North Olympic Salmon Coalition sample additional streams in the upper Hood Canal area. As part of the survey, scale samples were collected to estimate age and proportion of wild versus hatchery salmon. Length data was also collected. The number of fish and/or redds observed in index reaches were compared with index counts in prior years, when comprehensive surveys were also undertaken. The relationship between counts in the index reaches and total escapement is assumed to be stable. When flow and visibility conditions were good, redd counts provide a better estimate of escapement than counts of live or dead fish. Three tribal employees expended 1-3 days of effort per week conducting escapement surveys from mid-August through late December.

The survey data are essential for determining stock productivity, trends in survival of recruits per spawner, forecasting abundance and establishing exploitation rates. Biological sampling of spawners will additionally provide essential data on age composition of the returning salmon and an estimate of wild versus hatchery origin of adults.