'We need to be concerned': Rising temperatures lead to early fish kill in Alberta waters

EDMONTON -

Following a recent spike in hot temperatures, hundreds of dead fish have reportedly been spotted in various lakes and rivers in Alberta.

Due to a combination of extremely high temperatures and slow flows, Darryl Smith, the provincial fish chair for the Alberta Fish and Game Association, says summer kill has arrived earlier than usual.

Smith told CTV News Edmonton streams usually start to heat up late July to early August, but direct sun on waterways for upwards of 14 to 16 hours a day lower oxygen levels.

“People would say to me they were seeing 10 or 15 fish float by in a matter of 10 minutes,” he said.

“Other people reported seeing a hundred dead on the shores, like on the beach just where they were swimming.”

“Trying to suck in as much oxygen as they can, and you can look at them and their eyes were basically popping out of their heads,” Thomas Muis, a local fisher at Muir Lake, added. 

Smith said when he crossed Little Smoky River a week earlier, he looked down the river from the Highway 43 bridge and could see groups of fish kill all along the way.

“There was fish, actually dead fish in the water, you know moving with the water,” he recalled.

“Nature does things that we can’t explain. This could affect their overall sustainability.”

Smith said the public has to start looking at global trends. Amid rising temperatures, he told CTV News Edmonton this isn’t the first time he’s seen fish kill in flowing water.

“I think we all need to be concerned,” he said. “Some of our fish populations will be really susceptible to this type of event.”

Fish kill on the Little Smoky River. (Credit: Brad Vancuren)

Courtesy: Brad Vancuren

In order to help mitigate some of the effects of summer kill, Smith said it’s important to understand it and strategize future land use planning and earlier angling seasons.

A good dose of significant rain or precipitation would be very beneficial in getting more water into the rivers and streams. On top of that, Smith said cloud cover would also improve conditions for the vulnerable fish populations.

“I’m hopeful this is a one off,” he added. “But, I think in the future we should be prepared to see more of these.”