Most Ontarians know belugas only from nature documentaries, but a hardy population of this marine species persists in the province’s northern reaches. Can it resist the impacts of climate change?

Beluga whales that inhabit Ontario waters in Hudson Bay and James Bay are part of the 55,000-member western Hudson Bay population — the largest of seven distinct Canadian beluga population groups

EVERY YEAR, SOMETIME DURING the Arctic spring, beluga whales wintering amid the pack ice in Hudson Strait between Baffin Island and Nunavik and the Labrador Sea feel the tug of home. For most of the belugas in this area, “home” means the estuaries and coastal shallows of western and eastern Hudson Bay where they were born. As soon as the floe edge starts to recede and openings in the melting ice permit, they make their way west and south.

They reach their destination around mid-June and stay several months. During that time, these social animals — known for their white skin, large foreheads, intense vocalizing and “smiling” facial expression — use the coastal areas to feed, moult, calve and take refuge from predators, mainly killer whales and polar bears. “The pods go back year after year along the same routes to the same places that their mothers and grandmothers came from,” says Kaitlin Breton-Honeyman, a biologist who spent the past five years in Inukjuak, on eastern Hudson Bay, and is currently director of wildlife management at the Nunavik Marine Region Wildlife Board.

The scientific term for this behaviour is “matrilineal site and route fidelity,” meaning that the creatures learn the behaviour from their mothers. This trait is not unique to belugas but it is a key to understanding this whale’s biology and ecology — and why beluga conservation in Ontario can be understood only in the context of a larger, nuanced and intricate regional story.

Hudson Bay beluga high-density summer population core area (green) and migration routes (Source: Oceans North)

Some people may be surprised to learn that whales live in Ontario waters. But during summer, pods of belugas can be found along much of the province’s Hudson Bay and James Bay coasts. No firm estimate of their numbers exists. Instead, most “Ontario” whales are part of the 55,000-member western Hudson Bay population — the largest of seven distinct Canadian groups the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) has identified. Each of these populations is distinguished by its unique summer distribution, genetics and migratory pattern; together, the populations account for about two-thirds of the estimated 150,000 belugas found in Arctic and sub-Arctic waters. Several of the groups are threatened and require immediate conservation intervention, whereas the challenge in Ontario is more about protecting the beluga’s abundance while that is still possible.

THE WESTERN HUDSON BAY group’s summer range lies generally in a narrow 60-kilometre-wide band from shore running west from Ontario’s Polar Bear Provincial Park, through Manitoba waters, to Arviat in Nunavut. The largest concentrations are in Manitoba’s Nelson, Churchill and Seal river estuaries; in Ontario, belugas frequent the Winisk and Severn river estuaries. The animals, which weigh up to 1,500 kilograms and reach four to five metres in length, can live 60 to 70 years.

Kristin Westdal has a history with the whales in this area, first as a kayak tour operator and now as a marine biologist with the non-profit conservation organization Oceans North. She calls belugas “unique and special” animals: “They’re very curious whales, rich in Vitamin D and selenium (which counteracts the effects of mercury exposure), are a staple of Inuit diet and culture. Other threats include altered water flow in coastal estuaries due to hydroelectric dams and climate change.

Climate change is the biggest wild card, says Tanya Pulfer, Ontario Nature’s former conservation science manager. Among cetaceans, belugas are uniquely adapted to an Arctic existence by their snowy colour and the absence of a dorsal fin, which helps them swim under ice. Yet warming temperatures will mean less ice and more open water, which may expose belugas to higher predation by killer whales. Ice loss is also expected to bring more resource development, noise and ship traffic, which may lead to increased stress, pollution and collisions with ships.

Furthermore, climate change may alter the food web and relative abundance of species like Arctic cod, capelin and shrimp that make up much of the beluga diet. In light of these prospects, says Pulfer, “while this population may be doing well now, given multiple stressors we can’t assume this will continue.”

A further complication is that Ontario belugas within James Bay are, for the most part, members of different population groups, but the dynamics of this are not yet well understood, which makes management difficult. Some intermixing occurs, for example, between Western Hudson Bay whales and the endangered Eastern Hudson Bay population, which totals only around 3,500 animals — the legacy of commercial harvesting up to the mid-1900s from which that population has never recovered. Researchers also increasingly recognize that James Bay contains its own unique beluga population of up to 15,000 whales. These whales do not migrate; instead, they find enough open water between gaps in the sea ice around the larger islands to stay in the area all winter.

Belugas are “very curious” animals, says marine biologist Kristin Westdal

BECAUSE HUDSON BAY and James Bay are largely under federal jurisdiction, responsibility for the protection and management of Ontario belugas falls mostly under Fisheries and Oceans Canada (DFO). Increasingly, to expand its knowledge, DFO is consulting with local First Nations and Inuit communities.

Endangered and threatened beluga populations (in Eastern Hudson Bay, Ungava Bay, Cumberland Sound and the St. Lawrence Estuary) are more closely studied, given their precarious status. In James and Hudson bays research focuses mainly on the whale’s distribution, abundance and response to potential threats. “We want to make sure this population keeps doing well,” says Marianne Marcoux, a DFO research scientist. “We need to figure out how many there are, how the groups work. We’re interested in seeing how much they mix with other groups.”

Marcoux’s department did its most recent population assessment — a mix of aerial surveys and GPS location tracking — in 2015. DFO is also studying whether shipping routes in the area will become a concern.

For the moment, there are few large vessels in Hudson Bay, although DFO is worried about big ships since the port of Churchill re-opened. In contrast, ship traffic on the busy Atlantic and Pacific coasts of Canada is causing high-profile problems for whales there. With the growing popularity of whale watching in Hudson Bay, smaller tourist craft are also increasingly common. While no documented whale casualties or other conclusive signs that whale watching harms belugas have occurred, DFO has introduced rules requiring boats to stay at least 50 metres from the creatures in the Churchill and Seal estuaries (part of a package of national measures restricting approach distances to whales) — limits that tour operators say are unrealistic given the way belugas purposely approach vessels.

Westdal recently began a study of beluga behaviour in response to the presence of whale-watching vessels and kayaks. It involves picking random pods of belugas around vessels, measuring their distance from the boats and noting their behaviour, then tracking them for three minutes to record any changes. “I’m not sure what we’re going to find,” she says, “but after the fact, over a summer or two, you can look at a statistical analysis of behaviour.”

Less ice in Hudson Bay due to climate change may make belugas there more vulnerable to predation by killer whales

There are other ways to measure how belugas react to interactions with humans. Marcoux, for example, is supervising a master’s degree student at the University of Manitoba who developed a technique for taking samples of the “snot” belugas expel from their blowholes when they come alongside a boat. In the lab, hormone levels in this liquid can be measured and stress levels inferred, which Marcoux hopes will yield insights about stress levels in belugas in general and in response to different stimuli.

Both Marcoux and Westdal emphasize that work like this is important to build up knowledge that may help belugas in the future. Organizations like Oceans North are also pushing the federal government to ensure greater protection for belugas and other marine species by establishing a Marine Conservation Area in western Hudson Bay.

The prospects are encouraging, but the timeline is unclear. The federal government set aside funding in recent federal budgets to study the concept, and in a statement, DFO says it is “still exploring a potential protected area in Western Hudson Bay.” Parks Canada, meanwhile, says it “remains committed to pursuing a national marine conservation area” but adds that the proposal is in the early stages.

The boundaries of such an area might not extend as far east as Ontario. Even so, the initiative would help ensure that the belugas that spend their summers in Ontario waters — following and passing on their ingrained migratory cycle of birth and renewal — are better equipped to cope with whatever threats the future has in store.

SIDEBAR: A Whale of a Hybrid

Among whales, the beluga is most closely related to another distinctive Arctic species, the narwhal — a mottled brown-black creature best known for the male’s large “tusk,” a long tooth projecting from its upper jaw. Recently, a team of Canadian and Danish scientists confirmed the existence of a beluga-narwhal hybrid, dubbed the “narluga.”

The discovery began with a strange skull a Greenland Inuit hunter saved. In 1993, a Danish biologist proposed, on the basis of the specimen’s unusual size, shape and strange teeth (some long and pointed, others like corkscrews), that it could be a beluga-narwhal hybrid. A paper published earlier this year reported that the theory was confirmed through DNA and bone chemistry analysis. Researchers concluded that the skull was from a first-generation male hybrid offspring of a female narwhal and a male beluga. Paul Szpak, an anthropologist at Trent University who led the bone study, believes the animal got most of its food near the ocean bottom, “possibly because his very unusual teeth forced him to specialize on consuming prey that were not typically eaten by belugas or narwhals.”

Could there be more narlugas? Perhaps. But since belugas and narwhals generally encounter each other only in isolated northern waters, the chances of seeing another are small.

This article was originally published in the Winter 2019 issue of Ontario Nature’s ON Nature magazine.

Images courtesy of (top) pixabay.com/nikkikeldsen; (beluga pair) pixabay.com/cello5; (killer whales) 272447/pixabay.com.