California coastal (CC) chinook salmon are part of an EEL river catch and release sport fishery and are also acomponent of several chinook salmon populations available in californias recreational…

California coastal (CC) chinook salmon are part of an EEL river catch and release sport fishery and are also acomponent of several chinook salmon populations available in californias recreational ocean salmon fishery. Theeel and van duzen rivers in-river fishery attracts numerous anglers and supports visitor, tackle, and guideservice industries similarly, californias recreational ocean salmon fishery is conducted from ports throughoutthe state and significantly contributes to visitor, tackle, boating, and charter service industries. Access tothe in-river chinook salmon and ocean salmon fishery varies from easy access charter and drift boats, drive tobank or pier access to varying degrees of remote access trails and wading.california chinook salmon populations have experienced notable declines in abundance over the last 50 years. As aresult of these declines the CC chinook salmon evolutionarily significant unit (ESU) is federally listed asthreatened under the endangered species act (ESA). The CC chinook salmon ESU has a geographic range whichextends from rivers and streams south of the klamath river in northern humboldt county to and including therussian river in sonoma county. Californias third largest watershed, the EEL river, composes a significantproportion of the overall CC chinook salmon ESU range and natural production however, recent, and historical eelriver CC chinook salmon population data are limited. While this species is caught in recreational and commercialfisheries, the lack of data has made IT difficult to sufficiently determine population status and trend for thisesu and slowed the development of direct fishery assessment and abundance-based fishery management (ABM) (lacy etal. 2014). Accurate and cost-efficient annual and long-term monitoring of CC chinook salmon population status isrequired for information-based management of chinook salmon populations and in-river and ocean recreationalfisheries. This project will operate adaptive resolution imaging sonar (aris) cameras to monitor and estimate the escapementof EEL and van duzen rivers california coastal (CC) chinook salmon (oncorhynchus tshawytscha) during the fall andwinter of 2024-2025. This project has demonstrated that even in the highly variable flow conditions (dischargeand turbidity) that characterize the EEL river during the period of salmon migration, aris cameras are ableprovide valuable fisheries movement and population data. Enumerating the run size of adult chinook salmon is acritical management component for chinook salmon sport fisheries and commercial fisheries in california.additionally, the project provides near real-time data and run size estimates for northern california (NC)steelhead (o. Mykiss), an important in-river fishery in the EEL river.