Area of Expertise:
Keri Benner heads the Fraser Stock Assessment program for B.C. Interior, which collects escapement and wild smolt (Cultus and Chilko) data.
There are three traditional methods used in the salmon stock assessment in this area. The first method is a visual count, either from the land, a tower, boat or by helicopter, the second method is the use of enumeration fences and the third is mark and recapture. New technologies used include sonar (DIDSON- Dual Frequency Identification Sonar) and the Remote Operated Vehicle, which transmits real time video to a computer on the surface. The ROV surveys conducted in Chilko and Quesnel Lakes in 2004 and 2005 confirmed deep water sockeye spawning to depths of 45 metres. They also use telemetric monitoring which assists in explaining the disparity often associated between in season estimates and terminal area counts.
The high precision techniques such as enumeration fences, DIDSON or mark-recapture studies are used for stocks with expected escapements of 75,000+ (the actual technique is based on local characteristics), and visual surveys are used for stocks with expected escapements of less than 75,000.Request an edit to my listing