Nahlin Chinook Escapement Enumeration

This proposal involves enumeration of the escapement of Chinook salmon to the Nahlin River using sonar technology and analysis of GSI data from in-river fisheries, for 2016-18. Based on GSI and aerial survey data, the Nahlin River (into which both the Dudidontu River and Tseta Creek drain) is the second most important Chinook tributary in the Taku River drainage, supporting approximately one third of the total annual return. An accurate escapement figure for approximately one third of the drainage will be of considerable value on its own. However, this will be enhanced by coupling the count with GSI data from the lower Taku river, thereby permitting a ratio-based estimate of Chinook abundance drainage-wide for comparison with estimates currently generated using other methodologies.