Peter Dunfield has spent a long and distinguished career poking around rice paddies, peatlands, volcanoes and tailings ponds searching for nature’s tiniest grazers, single-celled micro-organisms that chew up methane.
That quest led the University of Calgary microbiologist to Syncrude’s west in-pit tailings pond in 2012, where he and his team isolated, identified and described two new micro-organisms – Methylicorpusculum oleiharenae and Oleiharenicola alkalitolerans.
“You have to use Latin when describing new species. The first means small-bodied methyl-eater while the second one is alkali-tolerating oil sands dweller,” says Peter. “Identifying these new species is fun, although our main job is to monitor the microbial communities in Base Mine Lake using DNA signatures, and compare them to an active tailings pond and a natural lake. Isolating and describing new microbial species is a sideline and takes a lot of tedious lab work. But when we find something interesting, we do it.”

Dr. Dunfield examining water samples from Base Mine Lake.
Photo Credit: Nadya Dunfield.
In the case of Methylicorpusculum oleiharenae – the small-bodied methane eater – what interests Dunfield is the micro-organism that was abundant in the west in-pit tailings pond in 2012 is now almost nonexistent in Base Mine Lake eight years later.
“That one has now almost disappeared from Base Mine Lake, which is an indication the lake is no longer a tailings pond.”
People should not be concerned that new species are evolving in tailings ponds, because microbial species generally do not evolve over short periods of time.
– Peter Dunfield
With these kind of species, we are talking about tens or hundreds of millions of years of evolution. What we isolated have already existed somewhere. My suspicion is they existed in oil sands seeps or other petroleum deposits but they found a really nice home in the tailings ponds. But they have already existed in nature.” he says. “There are still methane-eating bacteria in Base Mine Lake but different ones have colonized the lake because the conditions have changed and that’s a sign of progress. There have been dramatic changes in the microbes in the lake over the past six years – it really doesn’t resemble a tailings pond any more. It’s somewhere in between a tailings pond and a natural lake now.”

PhD student Chantel Biegler extracts microbial DNA from Base Mine Lake water samples. The DNA will be sequenced to determine what microbes are present in the lake.
Photo Credit: Nadya Dunfield.
Peter and a team of 10 present and former graduate and post-doctoral students have monitored Base Mine Lake since 2014 as part of a group of outside experts from different universities and research institutions working on different areas.
“We’ve enjoyed working on this project – Syncrude has been really good to work with as a partner. It’s a lot of fun – they have a diverse group assembled to look at this lake – we have limnologists, micro-climatologists, geochemists, biologists among other disciplines,” he says. “We’ve learned a lot from each other.”
Base Mine Lake has also provided lessons of its own.
“We’re quite surprised. We thought it might take decades for things to change. We certainly are seeing changes already.
– Peter Dunfield
“There have been dramatic changes, not only in the species of methane oxidising bacteria, but also in other key players such as phototrophic algae. The overall microbial biodiversity appears to be increasing. The lake is trending in a positive direction.”
Learn more about research at Syncrude.