THUNDER BAY -- What goes down the drain in this city can end up inside beluga whales, a living litmus test for the health of the Great Lakes system and the people who live here.
Calling the waters along Quebec home since the last ice age, there were an estimated 10,000 belugas in the St. Lawrence before whaling brought the population to around 1,000 before hunting stopped in the 1950s.
The population was expected to double after the whalers left. But by the 1970s when the belugas hadn't recovered researchers began asking why.
"We've been looking for explanations for that and the main explanation we have is that they've been exposed to toxic compounds that we've dumped in the Great Lakes and the St. Lawrence for decades," said Robert Michaud, scientific director with the Group for Research and Education on Marine Mammals.
Belugas, which typically live in the Arctic, are social mammals with long life-expectancies just like humans.
Michaud has spent his early mornings over the past 30 years heading out to the St. Lawrence. He's followed herds of belugas, watching babies become grandparents in their natural habitat.
"We think in doing so we probably will better understand how we can help ourselves surviving in this amazing environment," he said.
He's also seen the toxins in their tissue, the increased cancer rates and climate change threaten their environment, similar to human populations.
Bans on PCBs and other toxins helped recovery efforts for awhile but in the past 15 years numbers are on the decline again. There are now less than 900 belugas left in the St. Lawrence.
"They're telling us a lot about what we've done with our environment and it will take a lot of investment and time to change this system," Michaud said.
The belugas are a bellwether for the 40 million people who use the Great Lakes and St. Lawrence for drinking water, represented by the more than 100 mayors in Thunder Bay for the Great Lakes and St. Lawrence Cities Initiative conference, which wrapped up Friday.
Mayor Keith Hobbs said he never thought he'd be considering the beluga whale but Michaud, along with a presentation from Chicago's Shedd Aquarium discussing a recent partnership with GREMM, have shown how vital keeping the St. Lawrence whale population healthy is.
"If beluga whales are dying we need to fix things so our people aren't dying as well," he said.