Shock and awe in McMillan Lake
Last July there was electricity in the air at Trinity Western University.
To be more exact, the electricity was in the water of McMillan Lake. After two long all-nighters, we’d caught a total of 579 fish via electrofishing.
As expected, the vast majority of the fish were invasive and non-native. In fact, only 10 were native. However, we were shocked back in 2008 when summer student Dustynn Diack netted large numbers of pumpkinseed sunfish and largemouth bass. We hadn’t realized that aliens had taken over our lake.
Since then the B.C. Ministry of Environment has been advising us to try to remove this threat to native fish. A major concern is that during high water the lake overflows into the Salmon River, potentially exposing coho salmon juveniles and other native fish to marauding bass from McMillan Lake.
Electrofishing facilitates selective removal of large numbers of fish. In the weeks leading up to the operation in mid-July, the summer students, our environmental manager and I feverishly worked to prepare. I phoned up Golder’s electrofishing expert Tom Willms in Kamloops regularly to pepper him with questions.
Then the day finally came when Tom and his netter showed up with the electrofishing boat.
The boat produces an electric current that stuns fish at short range, and it’s the netter’s job to quickly scoop up stunned fish. We began electrofishing when it got dark in order to be able to sneak up on the fish.
Each time a large tub aboard the boat was filled with fish, the electrofishers brought them to shore where a team of summer students and I were waiting.
Non-native fish were euthanized with an anesthetic.
All fish were weighed and measured, and the native fish were released.
Epic memories of the two nights of electrofishing include the camaraderie of the team, the thrill of close encounters with hundreds of fish of all shapes and sizes, late night coffee runs, trying to handle slippery fish at 4 a.m., and seeing the sun rise as we headed home after a long night.
My thesis student, Melissa Bargen, was thrilled with the catch of 579 fish. At 4:30 am after two all-nighters she tiredly told me something like: “I’m going to look back on this time with awe.”
Melissa’s thesis work is focused on assessing our potential to eliminate bass.
However, by far her favourite catch from the two nights was an enormous 20 pound carp — an awesome product of our efforts to seize the day … the night … the fish.
David Clements is a professor of Biology and Environmental Studies at Trinity Western University.