Dave Yurkowski learned a great deal about Arctic ecology during his two week journey to the Canadian north this summer to study how climate change affects the behaviour of ringed seals. He also learned a lot about what’s commonly referred to as one of life’s most important virtues.
“You do have to be really patient,” the master’s student said of the time he had spend waiting for a seal to be caught in the nets he helped set. “You can be sitting there for hours. But that’s just part of field work. Once the seal gets caught in the net – that’s when the action starts.”
Born and raised in Winnipeg, Yurkowski is working on a master’s degree at the Great Lakes Institute for Environmental Research under the direction of professor Aaron Fisk, after earning an undergraduate degree from the University of Manitoba. He studies trophic ecology – feeding relationships of organisms in ecosystems – specifically focusing on the ringed seal.
“With climate change, it’s important to understand the animal’s movement related to the changes in the ice,” he explained.
Yurkowski set out on his trip to Pangnirtung, a small hamlet on the Cumberland Sound in Baffin Island, in mid-August. After an arduous 14-hour journey from Windsor to Toronto to Ottawa to Iqaluit to “Pang,” he spent several days prepping before a four-hour boat ride to a remote island near the Clearwater Fjord, where he spent about a week in a tent.
Accompanied by a post-doctoral fellow from the University of Manitoba, a local hunter, his son, and the son’s girlfriend, Yurkowski was on a mission to capture 10 ringed seals to collect tissue samples and outfit them with special satellite data recorder tags. Those tags are glued to the animal with a special epoxy and remain there until it molts the following spring. Among other things, it measures the lengths and depths of the seal’s dives, water temperatures and how long it remains out of water, painting a total picture of its behaviour. Every time it comes above water, all that data is transmitted to a satellite, which is then sent to Dr. Fisk’s lab for analysis.
Besides the tags, Yurkowski used a biopsy punch, which only penetrates several millimeters deep, to collect small skin and blubber samples. Those are analyzed to detect stable isotopes and other chemical tracers to get a picture of the animal’s diet. Such measurements as length, girth and rings on the animal’s claws were recorded to help determine its age.
Much of the work involved setting nets in the fjord and then watching and waiting for a seal to be caught so they could haul it in to shore to conduct their analysis.
“A lot of it was hanging out at camp trying to stay ready, because you had to wait for the tides,” he explained.
Yurkowski only captured one seal during the trip, an eight-year-old adult male that weighed about 85 kilograms. He admits he was a bit disappointed, but still says the trip wasn’t a complete waste because they’ll still get some valuable data on that animal.
This summer’s trip was actually Yurkowski’s fifth to the Arctic and he considers himself fortunate to have been able to go there so much.
“It’s a place where not many people have the opportunity to go and it really is beautiful,” he said. “It’s a pretty remote area, so it’s neat to go and see, and especially to be able to understand how the ecosystem there works. I’ll keep trying to go back as many times as I can.”
Yurkowski said he’s considering the possibility of pursuing a PhD, but is keeping his options open and is thinking about a career in science, either in government or academia.
“I’d definitely like to keep doing something Arctic-related, something environmental science-related,” he said.
Editor's note: this is one of a series of articles about students who were engaged in cool research projects and other scholarly activities this summer.