Rock River Chinook and Chum Habitat Assessment and Restoration Investigation

Chinook and chum salmon stocks in the Porcupine River watershed comprise an important subsistence fishery for the community of Old Crow and the Vuntut Gwitch’in Government (VGG). The management, monitoring and restoration of these stocks is of primary importance to local fisheries managers and previous R&E projects have aimed to better understand these stocks and to provide in-season estimates of escapement. In particular, the 2015 Chinook and 2013-2015 chum telemetry projects have provided a great deal of information regarding the spawning distribution of these species in the Canadian portion of the Porcupine River watershed, and have determined that the Rock River is a spawning area for both Chinook and chum salmon. The headwaters of the Rock River are located to the east of the Dempster Highway (north of Eagle Plains) and the stream flows into the Bell River approximately 75 km to the northwest of the highway. During 2015 radio tag tracking flights, 5 radio-tagged Chinook were found in the Rock River between the Bell River and a point 15 km downstream of the highway. This represents a notable portion of the applied radio tags (14%), once tag dropouts, mortalities and recaptures in the fishery are accounted for. To provide perspective, other well documented Chinook spawning areas such as the Miner and Fishing Branch rivers each had 13 and 4 tags, respectively. The analysis of the 2016 telemetry data is ongoing; however, there was a notable number of tags (4 or more) relocated in the Rock River, which is similar to the number of tags relocated in well documented spawning areas such as the lower Fishing Branch, Miner and Whitestone rivers.

This project investigates the potential for Chinook and/or chum restoration projects in the watershed. This includes the identification of limitations to productivity and options for stock or habitat restoration efforts. Aerial counts of both Chinook and chum salmon during the respective spawning periods will be conducted, and juvenile Chinook will be sampled during the summer months. During the juvenile sampling, baseline habitat information for Chinook and chum (water temperature, habitat quality, etc.) will also be collected. A secondary goal of the project is to collect baseline genetic information for both Chinook and chum salmon in the watershed to aid in determining if the Rock River population is genetically distinct from other spawning populations in the Canadian portion of the Porcupine River watershed. These samples can then be pooled with genetic samples collected for this watershed in previous years.