Tay River Chinook Access Investigation

The Tay River is a tributary of the Pelly River in the upper Yukon River drainage and is also is one of the larger tributaries within the Pelly River watershed with an area of approximately 3,500 km2.

Despite the large size of the watershed and suitable habitat,  Chinook were not found in previous radio telemetry studies. The telemetry studies included detailed aerial surveys of all possible drainages that could contain Yukon River Chinook populations (Mercer 2005, Mercer and Eiler 2004, Osborne et al. 2003). The lack of radio tagged Chinook in the Tay River system led the researchers to conduct a more detailed aerial investigation of the lower reaches of the system. This investigation and subsequent surveys indicated that an impediment to salmon migration (velocity barrier) was located approximately 5 km upstream of the mouth of the Tay River drainage (Mercer and Eiler 2004).

Due to the Tay River system’s relatively large size and probable spawning and rearing habitat, it may offer one of the better opportunities to significantly increase Chinook production within the upper Yukon River system. The increase in Chinook production would be accomplished by providing and/or improving access for Chinook salmon into the system through modification of the current barrier /impediment to salmon migration.

The objectives of this study are to 1) determine the presence or absence of Chinook salmon in the system,  2) quantify the  potential Chinook production of the Tay River system using existing production models as they apply to the upper Yukon River watershed, and 3) conduct an engineering pre-assessment to identify options to improve the passage of Chinook Salmon into the system.