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Four Southern British Columbian Chinook Salmon (SBCC) (Oncorhynchus tshawytscha) Designatable Units (DU) were assessed as Threatened or Endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) in 2020 and are currently under consideration for addition to Schedule 1 of the Species at Risk Act (SARA). The first half of the Recovery Potential Assessment (RPA) (Elements 1-11) first provides descriptions and status updates for the populations, an overview of biology and habitat requirements, and an assessment of the threats and factors limiting recovery. The major threats impacting DUs were assessed in a workshop with local experts and were determined to be climate change, natural system modifications, fishing, and pollution. All four DUs are considered to be at an extreme threat risk due to the severity and number of threats these DUs are facing. Based on the assessed threats, a population level decline of 71% to 100% is expected for DUs 1, 6, 13 and 15. Alleviating the multiple and complex threats to these DUs will be difficult, especially as many of the threats are exacerbated by climate change. The second half (Elements 12-22) provides potential recovery targets, a discussion of mitigation measures, population projections and a recommendation of allowable harm. Survival and recovery targets for each DU were suggested based on Wild Salmon Policy (WSP) benchmarks, with additional requirements about observed percent change in spawners. Data limitations from incomplete escapement coverage and unknown hatchery influences prevented many quantitative assessments and no modelling was completed. The risks imposed by climate change and continued anthropogenic development add additional uncertainty that was only described qualitatively. Based on the qualitative assessment for all four DUs, further harm may continue to jeopardize recovery. Therefore, to promote the survival and recovery of these DUs, it is recommended that all future and ongoing human-induced harm should be prevented so as not to jeopardize recovery. It is important to note that some activities in support of survival or recovery could result in harm but may have a net positive effect on the population and should be considered. [ABSTRACT FROM AUTHOR]

Eleven Designatable Units (DUs) of Chinook Salmon (Oncorhynchus tshawytscha), within the Fraser River were assessed as Threatened or Endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) in 2018, and are currently under consideration for addition to Schedule 1 of the Species at Risk Act (SARA). The first part of the Recovery Potential Assessment (RPA) (Elements 1-11) provided DU descriptions, status updates and an assessment of the threats and factors limiting recovery. This second half provides potential recovery targets, a discussion of mitigation measures, population projections and a recommendation on allowable harm. Survival and recovery targets for each DU were suggested based on Wild Salmon Policy (WSP) benchmarks, with additional requirements about observed percent change in spawners. A projection model was used to assess likely future trajectories and the chances of meeting these targets, however, results are only available for DU2 (LFRHarrison). Despite efforts to produce the required input parameters for the stream-type DUs, significant uncertainties and a considerable lack of data prevented quantitative assessment, and hence these DUs were assessed qualitatively. Results for DU2 (LFR-Harrison) indicate that reaching the survival target under recent conditions is about as likely as not likely (48% chance), while meeting the recovery goal is unlikely (16% chance). Risks imposed by climate change and continued anthropogenic development add additional uncertainty that was only described qualitatively. Based on the quantitative assessment for DU2 (LFR-Harrison) and the qualitative assessment for the remaining DUs, it is recommended that human-induced mortality and other sources of harm identified in the threats assessment should be significantly reduced and in some cases prevented to provide the best chance for these populations to recover. [ABSTRACT FROM AUTHOR]