FORT ST. JOHN, B.C. – Conservation Officers are investigating what caused a large number of fish to wind up dead in a lake north of Fort St. John.
A pair of photos were posted on the FSJ MAN CAVE BUY & SELL Facebook group last Thursday that appear to show a swarm of dead fish floating on the surface of a lake. According to the person that posted the photos, the dead fish were found in Inga Lake, which is approximately 75 kilometres northwest of Fort St. John on the Alaska Highway.
When asked, David Karns with the Ministry of Environment says that members of the B.C. Conservation Officer Service attended the lake, and are consulting with a biologist to find out what caused the fish to die enmasse. Karns says that one possibility being considered is the phenomenon known as ‘winterkill.’
According to the Minnesota Department of Natural Resources, winterkill “is a term used to describe the loss of fish in winter because oxygen was lacking in a waterbody. Submerged vegetation and algae create oxygen through the process of photosynthesis. During the winter, oxygen production is often reduced because ice and snow on the lake limit the amount of sunlight reaching vegetation. In small, shallow lakes the available oxygen can quickly be used up by live plants that consume oxygen in the evening, fish, and by bacteria that feed on dead and decaying vegetation. When the oxygen level declines, less tolerant fish species, and fish in poor condition overall, can begin to suffocate.”
Karns added that the Ministry of Environment should know more on what occurred later this week.