Unalakleet River Chinook Salmon Escapement Monitoring And Assessment 2013 2014 PDF Download

The 2013 Anchor River Chinook salmon (Oncorhynchus tshawytscha) escapement (4,401 fish, SE 117) fell within the sustainable escapement goal (SEG) range of 3,800?10,000 fish. High river flows changed the channel morphology at the confluence of the north and south forks, which rendered the 2003?2012 mainstem dual-frequency identification sonar (DIDSON) site unsuitable for monitoring escapement. Thus, for the 2013 season, the DIDSON was relocated about 0.3 RKM downstream and was operated throughout the high-water period. Once flows subsided, 2 alternative escapement monitoring sites were identified upstream: 1 on the south fork and 1 on the north fork. The north fork site was located approximately 1.5 RKM upstream from the confluence and the south fork site was located approximately 0.2 RKM upstream of the confluence. Weirs and underwater video systems were used at both sites to monitor escapement. The midpoint of the Chinook salmon run was 19 June. The daily Chinook salmon escapement counts were positively correlated with daily average river stage, but not with daily average river temperature. The dominant age class was ocean age 3 (43.5%, SE 4.1%). Overall mean length of males (604 mm, SE 15) was smaller than that of females (734 mm, SE 25). The inriver sport fishery was restricted by a series of emergency orders that probably resulted in a near record low harvest of 97 fish.