Bessette Creek Resistivity Counter

The installation of a temporary automated fish counting system (resistivity counter) is being proposed for the Bessette Creek watershed to provide accurate escapement information for Coho salmon. Escapements in this system are currently estimated via streamwalks and the Area-Under-the-Curve method. Migrations of returning Coho are multimodal and often extended over a long period. Their propensity to move during high water events, to occupy systems intermittently, and to behave cryptically/defensively once at their spawning grounds can make visual enumerations difficult. As a result, it is a real challenge to accurately enumerate Coho returns using ground surveys in complex habitat such as the Bessette Watershed. Visual counting conditions are frequently poor due to high flows, turbid and dark water conditions (tannins), which probably leads to an underestimate of the spawning escapement. One method that has proven effective in this situation is resistivity. It is able to remain in place during high water events if properly situated, can see past turbid conditions and can remain running for extended periods of time. An electronic counter, although initially expensive to install, can supply accurate escapement estimates of salmonids for many years to come at a fraction of the cost of existing labour intensive techniques. The information can be downloaded via telephone connection which accommodates remote monitoring of salmon escapement information into this system.

Operation over multiple years is necessary to calibrate the method with existing escapement estimates collected via streamwalk surveys. If the method proves successful, the plan is to replace traditional streamwalk surveys with resistivity counter monitoring on a long term basis. Long-term operation will be funded through existing Aboriginal Fisheries Strategy funding, providing a legacy of more accurate data and cost savings.

S19-SP36 Bessette Creek Resistivity Counter 2019 Report

S18-SP07 Bessette Creek Coho Enumeration Using a Resistivity Counter

S17-I33 Bessette Creek Coho Enumeration Using a Resistivity Counter (Year 1 of 3)