Makah Regional Salmonid Monitoring

Task A) Lake Ozette Sockeye smolt trapping in the Ozette River during outmigration provided an estimate of total sockeye smolt production. Hatchery and natural origin smolts were enumerated separately, as were all other salmonid species encountered. These smolt abundance estimates are necessary to measure marine and freshwater survival and productivity and relative contribution by hatchery-origin sockeye. The smolt trap was installed in the Ozette River in April, as conditions permited, and was tended through the end of the sockeye smolt outmigration in June.

Task B) Spawner surveys and sample collections were conducted on Lake Ozette beaches and in many of the Ozette tributaries. Surveys for spawning sockeye in Lake Ozette tributaries and on the beaches were conducted between October and January. Otoliths were collected from the carcasses, during beach carcass counts to determine age and release group. The WDFW laboratory in Olympia, WA read otoliths for age and thermal marks. Tissue samples were also collected from recovered carcasses and archived for future genetic evaluation of the integrity of the spawning aggregations, potential interbreeding with kokanee, and possible effects of hatchery practices.

Task C) Adult sockeye run-size entering Lake Ozette was monitored annually to estimate overall abundance. The adult sockeye run was recorded with an underwater video camera, which transmitted to a both time-lapse DVR recorder and a computer hard drive. Fish passages were recorded 24/7. Estimates for natural- and hatchery-origin adult sockeye were determined by reviewing images for adipose fin clip ratios. Population estimates were subsequently compared to estimates from both the adult weir at Umbrella Creek and the stream spawner surveys. Predator encounters and general fish condition were also evaluated. The estimates of survival to return results are essential to monitor the status of this ESU and have resulted in increasingly accurate measurements of abundance.

In conjunction with Task C a DIDSON/ARIS, sonar imagery tool was deployed in the river consecutively with the adult weir in an effort to research the feasibility of using this technology to replace the adult weir in future years. The data is assisting in developing appropriate protocols for deployment and image review. The weir is proposed for removal in future years to lower predation risk at that location. The ARIS was also used to assist with Task B, beach spawning surveys in Lake Ozette. The sonar imagery provides an opportunity to observe spawning salmon that aren’t visible with the regular visual surveys.

This project will allow Makah Fisheries Management to:
• Estimate the total number of adult sockeye entering Lake Ozette and separate the total into different spawning aggregation estimates.
• Determine the relative contribution of hatchery origin spawners in tributaries and monitor stray rates at all spawning locations.
• Estimate total sockeye smolt outmigration and relative hatchery contribution and survival in freshwater.
• Monitor smolt outmigration of other resident Lake Ozette salmonid populations.
• Identify all hatchery returns by release group and thus facilitate evaluation of performance and impacts of various hatchery programs.
• Collect and archive genetic samples for future monitoring and comparison.
• If the weir is in place: capture a representative segment of returning adults for broodstock to both maintain genetic integration with natural spawners and stay within allowed collection limits.
• If the weir is replaced with the DIDSON/ARIS: analysis of adult fish migrating without the weir and associated predatory component.

This project provides all components of data that determine estimates of the Lake Ozette Sockeye population size for outmigrating smolts and returning adults, of both hatchery and natural origin. It further facilitates the evaluation of the hatchery program’s release strategy investigation (i.e. which release stage is most effective in producing adult returns to the Ozette system). Accurate status information for both hatchery and natural components of the Lake Ozette Sockeye Recovery Strategy will lead to more effective recovery planning to assist this ESA-listed stock in regaining healthy VSP characteristics.

All of these components contribute to the overall monitoring of Lake Ozette Sockeye recovery efforts, per Hatchery Genetic Management Plan (HGMP) protocols and Hatchery Scientific Review Group (HSRG) recommendations. Monitoring populations and performance of both hatchery and natural origin sockeye is vital to planning restoration projects and evaluating overall population status. This information will allow adaptive management of programs to enhance recovery, detect and address possible negative effects, and ultimately contribute to delisting of Lake Ozette Sockeye as an ESA listed threatened species.