Stikine Enhancement Feasibility Study

For this study several new enhancement opportunities for Stikine sockeye were investigated in order to provide details upon which enhancement implementation could be pursued. For 2015, it is proposed that Tahltan Lake should be the sole focus of this final year of the enhancement feasibility study. This work would centre upon collecting and analyzing data to inform the detailed design and budget for creating additional sockeye spawning habitat at Tahltan Lake. Information thus far provides strong indication that this would be a promising new enhancement initiative. Analysis and modeling of hydrogeology data is considered to be a critical precursor to construction of the spawning area.

The intent of diversifying or expanding the existing Stikine enhancement program was reflected in the updated 2009 Transboundary PST arrangements. It states that: For the duration of this Chapter, the ‘Parties will pursue a diverse program to enhance sockeye production in the Stikine River …’ and that ‘The existing enhancement program may be expanded to include new activities such as barrier removal, habitat improvement and/or other agreed enhancement projects.’ (PST Appendix to Annex IV, Chapter 1, section 5.)

Tahltan Lake has ranked highest in enhancement feasibility since the beginning of this study. The lake is known to be spawning limited in terms of productivity and also to have underutilized rearing capacity. Field surveys during the feasibility study thus far have indicated that an area of riparian wetland on the north-east lakeshore has high potential for the creation of new sockeye spawning habitat. Beneath the wetland there is a partially confined aquifer within a gravel paleo-channel, which will likely provide essential groundwater flow and suitable substrate. The creation of a new spawning area would not only serve to increase wild productivity, but could also be utilized as an alternative site for the collection of brood stock. Such would be a useful manner of supplementing needs and addressing challenges of the current egg-take project.