In-season monitoring of harvest and effort from a large-scale subsistence salmon fishery in western Alaska

In-season management of salmon harvest requires real-time data. Specifically, following a brief period of open fishing, knowledge of harvest outcomes is useful when deciding the nature of subsequent fishing periods. This in-season management strategy is relatively new to the lower Kuskokwim River of western Alaska, where depressed salmon runs have caused restrictions to the subsistence fishery. We have developed an in-season monitoring program to rapidly inform managers about fishery outcomes from short-duration (6-24 hours) fishery openings. Completed trip information and one or more aerial surveys are combined to estimate daily effort and harvest from drift gillnet fishers spanning 11 communities and ~130 river kilometers. We present a re-analysis of the 40 monitored openers in June-July 2016-2023, and validate harvest estimates of Chinook, chum, and sockeye salmon by comparing them to post-season estimates derived from an independent long-term monitoring program. Our results indicate that the program has produced estimates of sufficient quality to inform in-season managers, although it will likely need alterations to be successful in years with less restricted fishing.