Edmonton Journal: Lakes created ‘from scratch’ try to replace fish habitat in Alberta’s oilsands region

Compelled by government requirements, several energy companies with operations in Alberta’s oilsands have constructed fake lakes nearby to replace fish habitat their companies have destroyed.

It’s not enough to dig a pit, fill it with water and leave, says University of Alberta biologist Mark Poesch, an assistant professor in the department of renewable resources.

“It’s really creating a new ecosystem from scratch, which is pretty exciting for a biologist,” Poesch said.

Poesch heads a high-tech project that attempts to optimize a so-called “compensation lake” for arctic grayling, a colourfully finned fish found mostly in the province’s north.

Alberta’s Endangered Species Conservation Committee says arctic grayling are a “species of special concern,” which means it may soon be threatened with extinction without human intervention.

In 2008, Canadian Natural Resources Ltd. was the first oilsands company to create a compensation lake. The $20-million, 80-hectare Horizon Lake is now home to some of around 116,000 fish that were scooped out of the Tar River system near CNRL’s Horizon operation near Fort McKay.

Poesch and his students are trying to figure out how many fish are now in the lake, and what species they are.

They have questions about how to make Horizon Lake into grayling heaven — what kind of plants should grow there? What smaller fish should be in the lake? What should they do if predators turn up?

Supported by CNRL and Mitacs, a non-profit organization that funds research, Poesch and his students will use sonar and DNA sampling to attempt an inventory of the whole lake for three to five years. The work began last summer, he said.

The hydroacoustic equipment is a sensitive fish finder that tells researchers the weight of fish present in a defined volume of water.

“This will be a very fine-scale technique than we could deploy to give both the oilsands company and the regulator (Fisheries and Oceans Canada) an idea of exactly how well this lake is doing,” Poesch said.

To figure out what species are in the lake, researchers will scoop poop, dead skin and tissue from water samples, then isolate and sequence the DNA.

These techniques will hopefully allow researchers to monitor the lake more affordably and efficiently than previously used methods.

Although this $1-million project examines Horizon Lake, Poesch would like to collaborate with other researchers to study other compensation lakes in Alberta’s northeast. Teck, Imperial Oil, Suncor and Shell also have, or plan to set up, the lakes for environmental mitigation.

In a news release from the companies, Ken Minns, a former head of habitat science for the federal government’s Department of Fisheries and Oceans, said the project’s results should help establish guidelines for how to run a sustainable compensation lake.

“There has always been an issue in the public domain related to large oil projects and whether or not they provide adequate environmental consideration,” Minns said in the news release. “It’s time to move away from contention and get serious — we know development is going to take place and the trick is to find the most environmentally benign way to do it.”

Byline: Janet French