This plan describes the coded-wire tagging of juvenile Chinook salmon Oncorhynchus tshawytscha on the Unuk River for the 2019 and 2020 brood years, which covers the coded-wire tagging of parr in fall of 2020 and 2021 and smolt in spring of 2021 and 2022, and sampling returning adults for age, sex, length, and coded-wire tags in escapement from the 2022 through 2027 return years. This study provides estimates of smolt and parr abundance, overwinter (freshwater) survival, mean lengths of juveniles, and harvest information of Chinook salmon originating from the Unuk River in Southeast Alaska. A separate project will be conducted on the Unuk River that employs aerial and foot survey peak counts to estimate large (≥660 mm mid eye to fork of tail length) adult Chinook salmon returning to the river in 2020 and 2021. The primary goals of this and the companion study are to estimate inriver run size, total run size, marine harvest-exploitation rate and harvest distribution, smolt and parr abundance, marine survival (smolt to adult) and overwinter survival (parr to smolt). The Alaska Department of Fish and Game uses this information to make local and regional management decisions, and the Pacific Salmon Commission uses the data for coastwide management and stock assessment through the Chinook Technical Committee.

This plan describes the coded-wire-tagging of juvenile Chinook salmon Oncorhynchus tshawytscha on the Unuk River for the 2021 and 2022 brood years, which covers the coded-wire-tagging of parr in fall of 2022 and 2023 and smolt in spring of 2023 and 2024, and sampling returning adults for age, sex, length, and coded wire tags in escapement from the 2024 through 2029 return years. This study provides estimates of smolt and parr abundance, overwinter (freshwater) survival, mean lengths of juveniles, and harvest information of Chinook salmon originating from the Unuk River in Southeast Alaska. A separate project will be conducted on the Unuk River that employs aerial and foot survey peak counts to estimate large (≥ 660 mm mid eye to fork of tail length) adult Chinook salmon returning to the river in 2022 and 2023. The primary goals of this and the companion study are to estimate inriver run size, total run size, marine harvest and exploitation rates, harvest distribution, smolt and parr abundance, marine survival (smolt to adult) and overwinter survival (parr to smolt). The Alaska Department of Fish and Game uses this information to make local and regional management decisions and to evaluate the Unuk River Chinook salmon escapement goal, and the Pacific Salmon Commission uses the data for coastwide management and stock assessment through the Chinook Technical Committee.

This plan describes the coded-wire tagging of juvenile Chinook salmon Oncorhynchus tshawytscha on the Unuk River for the 2017 and 2018 brood years, which covers the coded-wire tagging of parr in fall of 2018 and 2019 and smolt in spring of 2019 and 2020, and sampling returning adults for age, sex, length, and coded-wire tags in escapement from the 2020 through 2025 return years. This study provides estimates of smolt and parr abundance, overwinter (freshwater) survival, mean lengths of juveniles, and harvest information of Chinook salmon originating from the Unuk River in Southeast Alaska. A separate project will be conducted on the Unuk River that employs aerial and foot survey peak counts to estimate large (>660 mm mid eye to fork of tail length) adult Chinook salmon returning to the river in 2018 and 2019. The primary goals of this and the companion study are to estimate inriver run size, total run size, marine harvest-exploitation rate and harvest distribution, smolt and parr abundance, marine survival (smolt to adult) and overwinter survival (parr to smolt). The Alaska Department of Fish and Game uses this information to make local and regional management decisions, and the Pacific Salmon Commission uses the data for coastwide management and stock assessment through the Chinook Technical Committee.

An ongoing coded-wire tag project, used as part of a stock assessment program for Chilkat River Chinook salmon Oncorhynchus tshawytscha and coho salmon Oncorhynchus kisutch, will be conducted during fall 2020 and spring 2021 to provide estimates of smolt abundance and marine harvest for Chinook and coho salmon. This project uses modified Peterson 2-event mark-recapture methods to estimate smolt abundance, and port and creel sampling of coded-wire tags in mixed stock commercial and sport fisheries to estimate marine harvest for both species. Juvenile salmon will be measured for length and weight, marked with adipose fin clips, and tagged with coded wire tags in fall 2020 (juvenile Chinook salmon) and spring 2021 (Chinook and coho salmon smolt) as event 1 of the mark-recapture study. During event 2, adult Chinook salmon will be sampled for missing adipose fins, coded wire tags, age, sex, and length in Chilkat River fishwheels and drift gillnets, which are operated in the lower Chilkat River as part of a separate adult mark-recapture project. Adult Chinook salmon will be also sampled for missing adipose fins, coded wire tags, and age, sex, and length during Chilkat River drainage spawning grounds surveys to complete event 2 sampling. Coho salmon will also be sampled as adults during event 2 in the lower Chilkat River fishwheels. Age composition of Chinook salmon adults will be estimated by scale ageing techniques; age composition of coho salmon smolt and adults will also be estimated. The Alaska Department of Fish and Game uses these data to make local and regional management decisions. Chilkat Chinook salmon is a Pacific Salmon Commission exploitation rate and escapement indicator stock and has recently been added to the base model of abundance indicator stocks for the Chinook Technical Committee, which influences coastwide management.

In response to guidelines established in the Policy for the Management of Sustainable Salmon Fisheries (SSFP), the Alaska Department of Fish and Game (department) recommended that the Unuk River stock of Chinook salmon (Oncorhynchus tshawytscha) be designated as a “stock of management concern” in October 2017. This recommendation was adopted by the Alaska Board of Fisheries (board) in January 2018. Then, in October 2020, the department recommended continuing this designation and additionally recommended that the Chickamin River stock of Chinook salmon be added as a “stock of management concern”. A “management concern” is defined as “a concern arising from a chronic inability, despite use of specific management measures, to maintain escapements for a salmon stock within the bounds of the SEG [sustainable escapement goal], BEG [biological escapement goal], OEG [optimum escapement goal], or other specified management objectives for the fishery.” The escapement of the Unuk River stock of Chinook salmon has been below the lower bound of the existing BEG (1,800–3,800 fish) in 3 of the past 5 years (2016–2020). The escapement of Chickamin River Chinook salmon has been below the lower bound of the existing BEG (2,150–4,300 fish) in 4 of the past 5 years (2016–2020). Since 2014, the department has implemented conservative management actions to reduce harvest of Unuk River Chinook salmon, and by extension and proximity to the Unuk River, it is assumed those actions have reduced harvests of Chickamin River Chinook salmon as well.

This project surveys the Chinook salmon sport fishery on the Naknek River. Information will be collected on angler-days of effort by type of angler (guided vs. unguided), catch and harvest rates of Chinook salmon, as well as age (from scales), sex, length, and weight of Chinook salmon in the sport harvest. Data collected from onsite surveys will be used to document angler use patterns and to design regulations that will accommodate growth in the sport fishery and maintain angling opportunity. Results will also guide review of current regulations and will be used to assess the effectiveness of current regulations.

A creel survey will be conducted to estimate sport angler effort, catch, and harvest of large (≥75 cm mid eye to tail fork length) early- and late-run Chinook salmon in the lower Kenai River between the Warren Ames Bridge (river mile [RM] 5.1) and Slikok Creek sanctuary area (RM 18.6). Creel survey estimates will be geographically stratified in relation to the RM 13.7 Kenai River Chinook salmon sonar to provide angler effort, catch, and harvest of large Chinook salmon. A standardized inriver netting project will be conducted in the Kenai River at RM 8.6 to index abundance and estimate the age, sex, and length (ASL) composition of large early- and late-run Chinook salmon. Inseason estimates of Chinook salmon catch and harvest, used in conjunction with sonar passage estimates, inseason catch rates, and the length of returning Chinook salmon from the inriver netting study are used by fisheries managers for inseason management decisions to achieve escapement goals. This plan covers the creel survey and inriver netting studies for the 2021–2023 seasons.