Sockeye Smolt Enumeration at Babine Lake – Hydroacoustic Feasibility

Skeena Fisheries Commission (SFC) in collaboration with Lake Babine Nation (LBN) propose to extend a feasibility study to implement a new estimation method for enumerating the outmigrating smolt population from Babine Lake, British Columbia using hydroacoustic methodology in 2015. The proposed project will build on the success of a prefeasibility study conducted in 2014 in partnership with the Pacific Salmon Commission Northern and Transboundary Fund.

The hydroacoustic methodology being implemented promises a direct count of emigrating sockeye smolts. We propose to continue to develop this technique during the spring of 2015. The Babine Lake hydroacoustic project will be carried out concurrently with the standard mark-recapture method proposed to be conducted again in the spring of 2015: see project proposal “Babine Lake Sockeye Smolt Enumeration: Mark-Recapture”. This will permit detailed data comparison of the two procedures.
If feasible, the hydroacoustic technique has the potential to improve the accuracy of the Babine sockeye smolt estimate because it is not dependent on a number of variables related to mark-recapture methodology (tag retention, mortality, predation rates, change in behavior, etc.) and has the potential to enumerate the entire sockeye smolt population. In contrast, the trap currently used for the mark-recapture program samples approximately 1% of the total smolt population, with an estimate derived from this sample.