The Margaree Salmon Association in northern Cape Breton has been utilizing electrofishing as a method to monitor fish populations in the Margaree River over the past few years. This technique involves using an electric current to temporarily stun fish, enabling crews to safely capture, measure, and identify them before releasing them back into the river. Michael Fabiano, the association’s conservation co-ordinator, mentioned that electrofishing activities occur from May to late September with a low mortality rate of around two percent among the thousands of fish handled each season.
Ensuring the safety of the fish is a top priority for the association, and electrofishing is avoided when water temperatures are too high. Crews carefully regulate the current levels to momentarily disorient the fish, wearing protective gear such as heavy rubber gloves and chest waders to prevent accidents. Surveying various locations along the 120-kilometre river helps identify the most productive streams and assess the overall health of the fish population, which predominantly includes trout and Atlantic salmon, with occasional appearances of eels and lampreys.
This season, the association has captured and released approximately 1,800 fish across nine streams, a decrease from the previous year. According to Fabiano, last year’s challenging conditions, characterized by low water levels and high temperatures due to a severe drought, may have impacted the fish population negatively. Paul MacNeil, the association’s president, highlighted that the group intensified its scientific research efforts due to reduced data collection by Fisheries and Oceans Canada in the past five years. Established in 1982, the association aimed to gather reliable data to monitor river health amidst shifting climate patterns.
To bridge the data gap, the association collaborated with the Chéticamp River Salmon Association to acquire electrofishing equipment. While traditional fish counting methods involve swimming the river, MacNeil emphasized that electrofishing provides a more accurate assessment of juvenile fish populations within specific areas. The association’s adoption of electrofishing signifies a strategic move towards enhancing data accuracy and scientific monitoring of river ecosystems in response to evolving environmental challenges.