Protecting Canada’s rivers and lakes

A love of canoeing and a passion for science guide grad student’s journey
Image by Jake Dyson.

Canada’s vast northern landscapes are laced with rivers, streams and lakes, sustaining a rich variety of wildlife and plentiful drinking water. How can we best protect those gifts of nature for future generations, even as the country’s population and demand for resources swell?

Dalal Hanna spent the past five years exploring that question for her recently completed PhD degree in Natural Resource Sciences at McGill. She has already published three scientific articles based on the research. But she’s also managed to reach a much wider audience, sharing her findings and her love of the outdoors with kids, teenagers and curious adults in a variety of ways: running canoe-camping expeditions for young women, producing science podcasts, and telling stories from the field through a National Geographic program for up-and-coming leaders committed to protecting our planet and the life it supports.

“Freshwater ecosystems are a lifeline to our very existence,” Hanna says in a National Geographic video featuring her work on Canada’s rivers. “They support immense biodiversity, provide clean drinking water, and are powerful places where we can connect to both nature and ourselves.”

As a member of the McGill Sustainability Systems Initiative’s Landscape Scholars program, Hanna has also been part of a project bringing together young researchers from different disciplines to find ways to manage the planet’s resources more equitably and sustainably.

“Dalal is a brilliant scientist with a real knack for choosing interesting and important questions and absolute dedication to answering those questions deeply and thoughtfully through her science,” says Professor Elena Bennett, Hanna’s PhD supervisor and co-leader of the Landscape Scholars program. “She has an equally impressive commitment to public education about science, and especially about the valuable streams, lakes, and other ecosystems of Québec and Canada.”

Paddling across Canada

Growing up around Ottawa, Hanna got hooked on canoe-camping at summer camps. After earning a BSc degree in Environmental Sciences at the University of Ottawa in 2011, she set out on a six-month, cross-Canada canoe trip.

Photo of Danal teaching how to use a microscope
Image by Mikayla Wujec.

The expedition raised funds for the Canadian Parks and Wilderness Society and awareness for watershed conservation — and raised Hanna’s own awareness of “ecosystems that are so beautiful, and yet threatened.” While the group was canoeing along the Athabasca River in northern Alberta, for example, she was struck by the strong smell of nearby tar-sands processing plants. “It was one of the few places, paddling across the entire country, where we were told not to drink the water out of the river,” because of possible contaminants that couldn’t be easily filtered. “That moment marked me.”

Science storytelling

That journey crystallized Hanna’s desire to pursue graduate studies in freshwater ecology. At McGill, she did an MSc degree in biology, studying mercury concentrations in African freshwater fish. She authored two articles in peer-reviewed environmental journals with her supervisor, Professor Lauren Chapman.

Hanna next spent a year with fellow McGill graduate Andrea Reid producing a podcast called Science Faction Radio. To make sure the content would be accessible to non-scientists, Hanna and Reid limited the vocabulary in their scripts to the 1,000 most common English words.

“I learned a ton about communicating science,” Hanna says. “I think it plays a really important role in helping us understand how the world works – and through that we can make better decisions.”

Studying Quebec’s streams

For her PhD research in the Bennett Lab at McGill, Hanna turned her focus back to the forests and streams of rural Québec. Her research explored the best ways to keep rivers healthy. She spent much of her time gathering and studying samples from waters between the Mont-Tremblant and Monts-Valin provincial parks. She also measured the girth of trees along the banks of streams and rivers, to gauge how much carbon is stored in the watersheds.

One takeaway message from her work: changes in land use – converting forests to farms, for example – can have huge impacts on the freshwater ecology. Assigning protection status to a watershed is a strategy that can help protect streams, their biodiversity, and the ecosystem services they provide.

Close encounters with creepy critters

Hanna’s own fieldwork adventures provide plenty of storytelling fodder. Having bushwhacked through a tangle of small trees along a stream near Québec’s Parc national de la Jacques-Cartier one autumn day, Hanna paused to measure a tree trunk. As she reached out with her measuring tape, she looked down and saw thousands of wasps swarming at her feet.

“It wasn’t the first time I’d stepped on a wasps’ nest,” she says, “but it was the first time I couldn’t run away.” Fortunately, her clothing was heavy enough to provide some protection. Backing up cautiously through the thicket, she managed to beat a retreat with fewer than 10 stings on her hand – though she did lose the measuring tape.

Dalal netting under a log
Image by Jake Dyson.

Then there are the leeches. In a National Geographic “Explorer Classroom” event for schoolchildren on YouTube earlier this year, Hanna was asked by one viewer: “What’s the grossest thing you’ve ever found?” Her response: “a really big leech on my leg.” She reassured the kids, however, that “leeches aren’t really that bad -- you just remove them from your skin, and it’s not a problem.” (While they may seem gross, leeches are an important food source for many fish that we value, Hanna notes.)

Getting youth involved

Back in Ottawa, where she recently began a postdoctoral fellowship at Carleton University, Hanna aims to conduct research that will help federal policymakers identify the best ways to protect the country’s freshwater ecosystems.

She also hopes to expand Riparia, a Canadian charitable organization that she cofounded with her podcast partner Reid, now an Indigenous fisheries scientist. Riparia’s mission is to engage young women with freshwater science. The group’s signature program brings participants on a free week-long canoeing and camping trip in the Poisson Blanc Regional Park of Québec, where Hanna got her own first taste of canoe-camping as a youngster.

“I’m really committed to trying to break down some of the barriers that exist between scientists and the public,” Hanna says. “And I think one way of doing that is getting youth involved in the science that we do.”

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