Mid-Hood Canal Juvenile Salmonid Evaluation: Duckabush and Hamma Hamma 2012

Juvenile salmonid monitoring in central Hood Canal, Washington began in 2002 on the Hamma Hamma River and in 2007 on the Duckabush River. This work has been a collaborative project between the Washington Department of Fish and Wildlife (WDFW), Long Live the Kings (LLTK), and the Northwest Fisheries Science Center’s (NWFSC) Manchester Research Station. This report describes the juvenile abundance, egg-to-migrant survival, and outmigration timing of Chinook, chum and pink salmon. We also derived independent estimates for summer and fall chum salmon stocks in these watersheds via molecular genetic analysis. In addition, coho salmon and steelhead smolt abundance estimates were derived for the Duckabush. Duckabush River

A floating five-foot screw trap was located at river mile 0.3 (0.48 rkm) and operated by WDFW from January 10 to July 9, 2012. The abundance of juvenile summer chum salmon was over six times larger than fall chum (Table 1). Egg-to-migrant survival for summer and fall chum salmon ranged between 15.2% and 1.3%. The peak of the summer chum outmigration occurred 6 weeks earlier than the peak of the fall chum outmigration. Abundance of juvenile Chinook salmon was estimated to be 2,788 sub-yearlings with an egg-to-migrant survival of 22.3%. Abundance of juvenile pink salmon was over 14 times larger than estimates from 2008 and. The 2012 season marked the first season that abundance of yearling coho (7,082) and steelhead (2,299) were estimated. Hamma Hamma River

A floating eight-foot screw trap was located at river mile 0.5 (0.8 rkm) and operated by LLTK from January 30 to July 9, 2012. Juvenile fall chum salmon abundance was 3 times larger than the summer chum salmon abundance (Table 1). Egg-to-migrant survival averaged 0.9% for the fall stock and 2.7% for the summer stock. Abundance of juvenile Chinook salmon was estimated to be 12,306 sub-yearlings with an egg-to-migrant survival of 1.8%. Abundance of juvenile pink salmon was estimated to be 49,314 with an egg-to-migrant survival of 0.7%.