Development of a Genetic Baseline for Canadian-origin Yukon River Chinook and Chum Salmon

A genetics-based analysis can be used to identify to what river system, drainage, or sub-drainage a salmon is returning, long before the salmon actually reaches its spawning grounds. This type of analysis is generally referred to as genetic stock identification (GSI) and is used in both research and management. In the Yukon River, it is used to identify the stock of origin of salmon caught in commercial, subsistence, and test fisheries (e.g., Pilot Station or Eagle Sonar). This information on stock composition is used by fisheries managers to make in-season decisions and to reconstruct the run at the end of the season. It can also be used to understand where a juvenile salmon is from; this is particularly useful given that many juvenile salmon do not rear in their natal streams.

All of this analysis and its resultant information hinges on having a representative genetic baseline. This project aims to ensure that the genetic baseline used by researchers and managers is representative of Canadian-origin salmon. A good portion of the genetic baseline already exists thanks to the work on this project that has already taken place. The aim of this project is to gather genetic baseline samples from those areas and stocks that are currently un-represented or under-represented and, in this way, improve the accuracy of all the estimates developed using GSI. Canadian sampling efforts are focused on filling the baseline gaps by collecting tissues from poorly represented Canadian tributaries.