The white underbellies of dead fish floating catch the sun and contrast against the murky Sturgeon River. About a dozen protruding bellies dot the water from the Ray Gibbon Drive bridge construction site to the boat launch at Riel Recreation Park.
Dave Burkhart, Big Lake Environmental Support Society (BLESS) secretary and board member, said he has never seen so many dead fish in the Sturgeon and he is concerned about why they died.
“To see this number [of fish] in this concentrated area, particularly with the construction activities in conjunction with that — it’s rare. It’s really rare to see that number of [dead] fish in one place,” he told The Gazette as he stood along the riverbank on Aug. 8.
Burkhart initially noticed the dead fish on Aug. 3. He said he counted about a dozen of them and reported the fish to the City of St. Albert, Office of the Environment, the federal Department of Fisheries and Oceans, and Alberta Fish and Wildlife.
The environmental co-ordinator with the city and a fish biologist with Alberta Fish and Wildlife said this is an annual event compounded by angling in the area.
Melissa Logan, Sturgeon River and Natural Areas environmental co-ordinator with the city, said her contractor initially reported 20 dead fish around the construction area, which they investigated on Aug. 2.
Logan said she monitors the site weekly, and she isn’t concerned that silt due to the construction had anything to do with the fish deaths.
Logan said there was a section of trail that was removed just before the river level went up, but directly underneath the asphalt is highly compacted gravel, “so, there's very minimal risk of sedimentation from that. And as work on the trail continues, we will be using things like coffer dams and silt fences and erosion blankets to ensure that our input into the river is minimized as much as possible,” she said.
There are also protective measures in place.
Logan said they do weekly inspections, there is a site superintendent who inspects the site daily, and they keep the equipment as far away from the water as possible.
“We do not allow refueling of equipment within 100 metres of the bed and shore. All equipment must use drip trays to ensure that any leaking fluids are captured,” she said.
Logan said the city is also bound by conditions under fisheries permits.
“We have recommendations for further measures for protection for the river written by a qualified aquatic environment specialist. The contractors do follow those recommendations,” she said.
Dr. Stephen Spencer, a fish biologist with Alberta Environment and Parks, said the 20 dead fish is a pretty low number of fish, but it is still concerning.
“We don't like to see fish dying,” Spencer said, adding that August is typically “fish kill month.”
Fish kill is something that happens on an annual basis in the Sturgeon River, said Logan.
“It doesn't seem to be isolated to any one spot. It's happened near the bridge. It's happened downtown. It can happen anywhere,” said Logan.
Spencer said there are several environmental factors that make life difficult for fish in August.
In the later summer months, the water temperature goes up and warm water holds less oxygen. Plant growth becomes quite thick, and longer evenings mean plants respire and use up oxygen during the night, which causes the dissolved oxygen levels in the water to drop significantly, Spencer explained.
Logan said the city has also been seeing a high number of fish kills under the bridge from high angler pressure.
“It’s a very popular spot for fishing and the fish are quite damaged. They get injured over and over from catch-and-release fishing,” she said.
At this time of year, when the oxygen levels dip and the fish are already stressed, catch-and-release fishing “can push them over the edge as far as survival,” Spencer said.
Burkhart said he was near the bridge on the Saturday before the dead fish showed up. He saw people wading through the water and fishing from scaffolding under the bridge, but he has his doubts that angling pressures caused the fish to die.
“If that is the cause, if catch and releases is causing those fish to die, then I think they should close fishing in the Sturgeon River, until such time as conditions improve, because typically that doesn't kill. Catch and release typically would not kill,” he said.