Worry in the water
WARMING EXTENDS WHALE-WATCHING TOURISM SEASON, BUT LOST ICE INCREASES EXPOSURE OF WORLD'S LARGEST BELUGA POPULATION TO PREDATOR ORCAS AND POSSIBLE RISKS FROM ADDITIONAL SHIP TRAFFIC
(Supplied by Oceans North)
OCT. 24, 2020, WINNIPEG FREE PRESS
CHURCHILL — Some feelings you just know will stay with you for the rest of your life.
Paddling a kayak out into the Churchill River as the sun starts sinking in the late summer sky, dipping the paddles into the murky water, whistling or cooing for your submerged friends to come and say hi.
Then you feel it: the rumble of bubbles on the underside of the kayak that reverberates through the walls of the vessel — you know they’re on their way up from the river’s depths.
Belugas are unlike any other whale species. They’re relatively small (about half the size of an orca), curious and seemingly unafraid, with rounded, gleaming white noggins that can swivel on their bodies because their vertebrae aren’t fused the way they are in many other species.
Hundreds of them make themselves known to a group of tourists over the course of a couple of hours. The grey young and adolescent whales assert themselves even more than the picturesque white adults.
They don’t seem to tire of the interactions; swimming up alongside kayaks and paddleboards. They bump you. They swim alongside you. They cock their heads so they can stare at you with their beady black eyes.
Churchill might be known for polar bears, but the bears aren’t social like these summering whales.
The estuaries in southwestern Hudson Bay are home to the largest population of belugas on Earth, which most recently was estimated to be about 54,500 animals in 2015, according to a survey conducted by Fisheries and Oceans Canada.
Winnipeg Free Press reporter Sarah Lawrynuik has a chance to paddle alongside belugas as they socialize with tourists kayaking in the Churchill River. (Faye Kehler)
These belugas primarily summer in the mouths of the Churchill, Nelson and Seal rivers, where they are relatively free of predators and can calve, moult and feed in peace.
They begin arriving in mid-June and they leave at the end of August and into September for the Hudson Strait as they retreat to the Arctic Ocean for the winter months. Completely defenceless against their predators, these animals rely on their habitats to keep them safe.
It seems undeniable that the western Hudson Bay belugas will have their lives upended by climate change, as their entire existence is dictated by the freeze-and-thaw cycles of sea ice in the bay — but as it turns out, exactly how climate change will impact these marine mammals is still poorly understood.
"Not a lot of studies have looked at climate change with respect to belugas. Most of the Arctic whale species, or marine mammals generally, we’re still kind of at the stage of trying to understand them a bit more basically," says Steve Ferguson, a research scientist with Fisheries and Oceans Canada.
“Not a lot of studies have looked at climate change with respect to belugas. Most of the Arctic whale species, or marine mammals generally, we’re still kind of at the stage of trying to understand them a bit more basically.”
— Steve Ferguson, research scientist with Fisheries and Oceans Canada.
While climate-change research has progressed with respect to animals such as seals, it is more difficult to study changes in populations of animals with longer lifespans and lower birth rates, he explains. "The population dynamics don’t change very quickly because they’re so long-lived." The upper range of a beluga’s lifespan has been estimated to be between 50 to 80 years.
There are a number of things that put this healthy whale population at risk for future decline, especially in a changing climate. For one, their loyalty to their calving grounds means these animals will continue to return to this place, no matter what. That fidelity to a single spot puts them at greater risk should the area ever become less safe for them. It’s something that’s caused beluga populations in other parts of Canada to be particularly unresponsive to conservation efforts after population decline began.
Dwight Allen co-owns Sea North Tours, the largest beluga tour business in Churchill. For him, longer ice-free seasons also means a longer tourism season. He says while he used to shut down towards the end of August, he can now stay open well into September. (At least in a normal year; he closed down on Aug. 24 this year, but due to low tourist traffic as a result of the pandemic, not because of the whales leaving the river.)
Two juvenile beluga whales follow behind a Zodiac on a tourist outing by Sea North Tours. (Sarah Lawrynuik/Winnipeg Free Press)
"It does bring a longer season for beluga watching," Allen says. "So, there’s a lot of potential in running a longer season. Tourism in Churchill is very important for our community and for all of Manitoba."
Ferguson says Allen’s observations that whales remain several weeks longer roughly line up with what he would expect to see, given the lengthening of the open-ice time on Hudson Bay, however, no research has yet been done looking at changes in migration patterns.
But with longer open-water seasons for the belugas, so too is there a longer season for other species to wander into the bay which, on some occasions, brings predators to the belugas’ doorstep.
"We’ve had killer whales come into Hudson Bay fairly regularly and attack beluga," Ferguson says. "Even around Churchill it’s been observed."
“It does bring a longer season for beluga watching. So, there’s a lot of potential in running a longer season. Tourism in Churchill is very important for our community and for all of Manitoba.”
— Dwight Allen, co-owner of Sea North Tours
Orcas, apex predators, have been observed all along the western coast of Hudson Bay feeding on beluga whales during the summer months, gaining access to the bay only during the ice-free season. Beluga whales have adapted to have a smooth back and no dorsal fin, which allows them to live and feed under sea ice, since they can run alongside the ice and find breathing holes. The killer whale is prohibited from living for any period beneath the ice because of its iconic dorsal fin.
Beluga whales in Button Bay, just west of where the Churchill River flows into Hudson Bay. With longer open-water seasons for the belugas, there is a longer season for other species to wander into the bay which, on some occasions, brings predators to the belugas’ doorstep. (Sarah Lawrynuik/Winnipeg Free Press)
Research using satellite telemetry has shown that when a killer whale wanders into beluga-filled waters, the white whales change their behaviour: reducing their range, moving closer to shore and away from attack sites.
Research on the history of orcas in Hudson Bay found that the predator’s presence was tracked by local Indigenous groups starting in the mid-1900s. A study published in 2009 in Ecological Applications found that, "killer whale use in the region has intensified considerably, especially in western Hudson Bay. This increase is significantly related to a decline in the sea ice in Hudson Strait."
The last confirmed sighting of a killer whale in western Hudson Bay was in 2015.
"Then we did have a couple of fairly major ice entrapments of killer whales in the last 10 years and we think we may have lost a lot of the killer whales that were coming into Hudson Bay. We haven’t heard as much about them more recently. It’s hard for the killer whales to figure out the sea ice, they’re not used to it the way beluga are," Ferguson says.
So, the beluga whales are safe, for now. But it’s likely only a matter of time before a new pod of orcas figures out how to navigate into this easy feeding ground. An article published in the Canadian Journal of Zoology in March recommended more study into the demographic and ecological knowledge of killer whales across the Canadian Arctic.
Sitting cross-legged on a blanket laid out across a gravel patch, Erica Gillis and Terry Palmer stare out across the Churchill River, sipping coffee and watching for the white streaks of a whale’s back in the water. From their perch at the Port of Churchill they are tracking and observing the behaviour of belugas in the river when they are undisturbed.
Terry Palmer (left) and Erica Gillis document belugas’ behaviour in the estuary from their perch at the Port of Churchill. (Sarah Lawrynuik/Winnipeg Free Press)
Gillis, employed as a research manager at the Churchill Northern Studies Centre, is on contract for Oceans North, a not-for-profit organization working on ocean conservation programs in the Arctic. Palmer, a 15-year-old town resident and high school student, works as a research assistant. The information they’re gathering is for a research project that aims to document whale behaviour in the absence of boats, as well as in the presence of both tourist vessels and commercial transport ships.
They sit for hours. While whales are visible all over the place, in order to take notes on their behaviour, they have to be able to follow the same creature’s actions for three minutes. As Gillis spots them, Palmer starts the stop watch, and they dictate notes on behavioural observations to one another.
"We look for things like if they’re feeding, if they’re travelling, if they’re socializing, if they’re milling or if they’re resting. Then, when we’re (observing them from) the boat, we’re also looking to see if they’re interacting with the boat or kayak," Gillis explains. "We also look for what kind of group it is. Is it all adults? Or is it mostly juveniles? Or, if there’s a calf in a group, then that gets classified as something different."
Oceans North is pursuing this line of research because with longer ice-free seasons, there is speculation that soon there will be increased shipping through the port. What impact that could have on belugas is unknown but it is a source of great interest and concern for researchers, especially since the port is nestled along the shores of the estuary.
This monitoring project began in 2019 and will continue through next summer. The hope is that this research can fill in the gaps of missing information about how belugas are influenced by increased traffic and inform policy decisions going forward, says Chris Debicki, vice-president of policy development with Oceans North.
Tourists snap photos of belugas as they surface in the estuary. The whales are curious and like to follow along behind Zodiac watercraft. Guides suspect its the bubbles from the motors that attract them. (Sarah Lawrynuik/Winnipeg Free Press)
"There’s no outcome we’re certain of, we’re just looking to understand it better," Debicki says. "We’re trying to find a responsible way to formulate recommendations on how belugas and a community can continue to coexist."
Two researchers from the University of Manitoba are also looking at the intersection of increased shipping and the health of the beluga population. Emma Ausen, who is completing her masters research, is studying behaviour patterns using aerial photos of belugas in the Churchill River estuary.
"I’m hoping to see some kind of patterns in how they behave, especially connected to tide, weather conditions and boat/vessel presence," she says.
Veronica Coppolaro, a physicist completing her PhD at the Centre for Earth Observation Science, is using hydrophones (underwater microphones) to study the vocalizations of belugas to further understanding of how they are using the estuary.
From her work she hopes to understand how the whales’ use of the area changes in the presence of the sound pollution from the commercial ships, something known to have great impact on other whale species that rely on underwater communication but never studied in the western Hudson Bay beluga population.
When a hydrophone dips beneath the surface of the Churchill River, it brings the water to life in a way that wasn’t evident moments before. Broadcast over the speaker are the squeeks, whistles, chirps, moans, moos and clicks of the plethora of belugas that dance in the water, just out of sight. Belugas are referred to as the "canaries of the sea" because of the enormous range of sounds they produce.
"They use different sounds for different reasons," Coppolaro explains. "The socializing calls, they’re so varied, they make so many different sounds. But then they have the clicks, which are super high-frequency, and they’re used for navigation, echo location and searching for food, mainly. So, by knowing which kind of calls they’re making, we know what’s going on. (The question is) if a boat is approaching, will they stop echo locating? So you wouldn’t hear the clicks anymore, maybe you hear something else, like a call to tell the others to get out of the area, for example."
Marianne Marcoux is supervising Coppolaro’s research and works as a research scientist with Fisheries and Oceans Canada at the Freshwater Institute in Winnipeg. She studies narwhal and beluga populations in the Arctic. Marcoux says similar research to Coppolaro’s was conducted in the St. Lawrence River, and there it was observed that the belugas shifted the frequency in which they communicated in response to noise pollution.
"We’re working together with (Fisheries and Oceans Canada) to see if this could give us an idea of how ships should behave when they come in," Coppolaro says. "It could be as easy as slowing down when they come into the estuary, or only using a certain part — though there is already a channel that they mostly use — or just coming in at different times of day, when belugas are less active."
Coppolaro says she feels the pressure of the expectations that come with doing the exciting, but daunting research that could ultimately inform policy decisions.
This article was a part of a 16-part series published in the Winnipeg Free Press titled Bearing North: An Exploration of Climate Change’s Impact on the Churchill Region. Read more of the series here.