Arctic Science Series: Passion for the Polar Bear

When a passion for the outdoors meets a knowledge of how bad chemicals could be for the environment, a career studying the Arctic and the iconic Canadian polar bear is born.

“The Arctic and the polar bear always enthralled me,” says Dr. Robert Letcher, a senior research scientist with Environment and Climate Change Canada (ECCC). He still remembers his epiphany after completing his Masters degree in chemistry. “It became established in the 1980s that the Arctic was not pristine with respect to chemical pollution. The Northern Contaminants Program started in 1991, and I had to be part of it. I started my Ph.D. thesis work that same year on pollutants in polar bears under the supervision of Dr. Ross Norstrom (deceased). I was driven to be part of the effort to work towards solutions.” His passions combined to steer him on a path towards studying the substances that harm the wildlife, fish, water and land in northern ecosystems with a central focus on polar bears.

Of the 26,000 polar bears that live around the globe, two-thirds of these animals are in Canada’s unique northern regions. They were listed as a species of Special Concern under the Species at Risk Act in 2011, which is a designation given to species that may become threatened or endangered. The polar bear faces many stressors in a changing Arctic including climate change, habitat loss and degradation from sea ice loss and oil spills, and chemical pollutant exposure and effects – and that is Robert’s part of the polar bear research puzzle.

Beyond the cultural significance of polar bears to Indigenous Peoples and their integral use by Inuit for food and clothing, there is another connection that is addressed in ECCC’s research. “The polar bear is on the same level on the food chain as humans, both are at the top,” says Robert. “Indigenous Peoples and polar bears consume similar country foods in their diets like whale blubber and seals, so humans face comparable exposure risks to contaminants as do polar bears.” Therefore, this research provides an early warning support not just for wildlife health, but human health as well. It also reinforces the growing importance of One Health, an approach that recognizes the connection between the health of people, animals and the environment, when carrying out research in the North.

Robert works closely and in collaboration with Inuit communities in Nunavut to conduct this research. For the monitoring and research that Robert leads, Hunters and Trappers Organizations in Sanikiluaq, Whale Cove, Arviat, Rankin Inlet, Pond Inlet and Clyde River collect fat, muscle, liver and teeth samples from polar bears after they are harvested. Robert says the Inuit are equal partners in the research including the sharing of local and traditional knowledge that is used to interpret the meaning of contaminant data for collected samples that are analyzed in his lab at ECCC’s National Wildlife Research Centre in Ottawa. Over time, levels of old and new chemical contaminants are compared to assess the current state of contaminant exposure for the species that may be effecting their health, and the ongoing changes due to the influence of climate change. Robert does not do this research alone and acknowledges his team of many ECCC staff, students and other collaborators that have been part of this work over the years.

In connection to the Northern Contaminants Program under Crown-Indigenous Relations and Northern Affairs Canada, Robert monitors for Persistent Organic Pollutants knows as POPs that include pesticides and flame-retardants, metals such as mercury, and plastics, which are a new concern in the Arctic. His research informs species management decisions and assesses the effectiveness of international regulatory restrictions established by the Stockholm Convention and Minamata Mercury Convention. He works closely with counterparts in Denmark and Greenland, as Greenland is home to polar bear subpopulations as well. One of Robert’s closest and a long time collaborator on polar bear research was Markus Dyck, a polar bear biologist with the Nunavut Department of Environment, Government of Nunavut, who died tragically in a helicopter crash near Resolute Bay in April 2021. Markus shared the same passion as Robert about polar bears, and Robert was quoted in a Toronto Star article saying, “He (Markus) loved animals (and especially polar bears) and wildlife and truly believed in the meaning and purpose of what he was doing.”

Robert is proud to be part of the long history of polar bear research at ECCC where his passion for the outdoors and his chemical knowledge sparked a curiosity for the iconic bear. “The chemicals in question are largely human-made and are potential stressors to all life in the north, and perhaps more so for polar bears as they are at the top of the Arctic marine food web,” Robert reflects. “There will be no end to this work, we must be vigilant, and we need to continue to determine and monitor the growing number and levels of chemicals that reach the north and exposure to the bears. Doing so is necessary so that we can take action to minimize, regulate and eliminate the use of POPs and other chemicals such as mercury that are of concern in the Arctic, and can build-up in the tissues of polar bears and other wildlife and humans.”