Dispatch from Hudson Bay, Manitoba: Unraveling the Mysteries of Belugas

Dispatch from Hudson Bay, Manitoba

Scott HighleymanScott Highleyman, international Arctic director for The Pew Charitable Trusts, last week travelled to the Seal River estuary on Canada's Hudson Bay, along with staff of Oceans North Canada, as part of a three-year study of the Arctic's largest population of beluga whales.

Pew's Oceans North Canada research team, in collaboration with Ducks Unlimited, is in its second year of examining how belugas use this crucial summer habitat and why the Seal River estuary and two others like it in the region merit protection. 

Seal River Estuary: Belugas and Beyond

By Scott Highleyman
July 16, 2013

SEAL RIVER, Manitoba— One way to think about Hudson Bay—the world's largest northern inland sea—is as one giant estuarine system. Massive estuaries like the Seal River, drain huge upland areas, mixing fresh water and nutrients into the ocean through a delta of wetlands, marsh, bog, and tussocks. No one yet knows why beluga whales return every year to this estuary, something our research is trying to discern. But it's easier to understand why so many other species rely on this productive region.

The dynamic mix of fresh and salt water, nutrients from the land, and energy from the sun help estuaries such as the Seal River function as engines of marine productivity.

Traveling by boat from one beluga survey line to another on July 9, we saw a mother polar bear and her cub swimming offshore. At roughly the same time, other members of our team observed eight polar bears circling a beluga carcass on shore in the estuary. On their way back to the lodge, the team members passed another male bear swimming in the ocean. That made 11 polar bear sightings in one day.

Polar bears are excellent swimmers, as comfortable in Hudson Bay as on its shores.

During the week, we dropped off an observer for the Manitoba Breeding Bird Atlas on the south side of the Seal River estuary. Right away, she recorded seeing 5,000 black scoters in the water. The black scoter, an Arctic sea duck, flies here from as far away as Georgia on the eastern seaboard of the United States. She estimated that 4,000 additional birds were wheeling around in the air. When we did background research on the Seal River two years ago, the best estimate we could find for the black scoter population in the region was 2,000 birds. Now she had seen 9,000 of these sea ducks in five minutes.

Black scoters wheel overhead offshore from the Seal River estuary.

Walking up from the beach into the willow thickets, the bird observer found the nest of a northern harrier with three young birds, as well as nesting least sandpipers and savannah sparrows. No one really knows where all the black scoters nest. Ducks Unlimited is working with the government of Manitoba and the U.S. Fish and Wildlife Service on aerial surveys in the Seal River region to estimate the numbers of black scoters using this habitat.

Humans have relied on the abundance of this estuary for thousands of years, and still do. One of our boat pilots, Johnny Mamgark, is from Arviat, Nunavut, an Inuit community 120 miles north of the Seal River that depends on caribou, geese, and beluga as mainstays of their diet. Local wisdom, as well as numerous government studies, confirm that maintaining this subsistence diet—called “country food” in Canada—is the key to reducing diabetes, heart disease, and other ailments related to processed food that have swept through communities in Nunavut.

The Arctic tern is one of more than 60 bird species observed in this region.

On the last day of beluga research in the field, we finished our final transect survey line at 10 p.m. In the Arctic twilight, our two boats stopped at Hubbart Point between the Seal River and Arviat, close to the border with Nunavut. We saw three more polar bears, including one so full from feasting on a beluga carcass that it barely stirred upon seeing our boats. On shore, Johnny showed us stone fox traps, food caches, graves, and rock foundations from summer dwellings that were used by his ancestors.

High tide lapped at the napping spot of two polar bears at Hubbart Point north of the Seal River.

But the Arctic is as much about the future as the past. Johnny and his people still use this region, camping amidst the lichen-covered stones placed by his ancestors. Today, his community and the residents of Churchill, Manitoba, are busy building a modern economy. Churchill has become a hub for ecotourism as visitors flock there to see beluga whales and polar bears. The town also has a deep-water port, and residents hope to capitalize on increased shipping made possible by the melting of Arctic ice.

A gray beluga calf with mother.

The belugas, bears, birds, and people in the region all need the Seal River and neighboring estuaries to continue to produce natural wealth from the mixing of land, water, and sunlight. Our beluga study is one small part of understanding and protecting this habitat so that its abundant biological life, and the people who depend on these natural resources, can thrive.

Counting Belugas

By Scott Highleyman
July 11, 2013

Seal River, Manitoba—The ache in my lower back from the shock of the Zodiac boat repeatedly slamming into the waves was a jarring reminder of the difference between participating in a survey of the beluga population in this fast-changing environment and looking at a two-dimensional research plan on paper.

A sketch of the survey plan in marine biologist Kristin Westdal's notebook.

The sketch of the research ahead showed 10 “transect” lines, or routes, each 15 kilometers in length from shore to open ocean, neatly spaced in five-kilometer intervals starting south of the Seal River and ending to the north. The plan was for our two boats to work in tandem on parallel lines, leapfrogging along the grid to count beluga whales. But the paper, with its clean straight lines, didn't convey the 20-to-30-knot wind gusts that kicked up the waves. It didn't show the rocks that threatened to take a bite out of the boat's propeller or the tides that uncovered extensive boulder fields and mud flats.

A research boat launches at dawn.

Fortunately, the field biologists and boat drivers knew the survey plan would be implemented in a constantly changing, three-dimensional sea. Kristin Westdal, the marine biologist for Oceans North Canada who set up the survey, used available charts and local knowledge to avoid most of the rocky reefs.

A bird's-eye view of two research ¬boats in the Seal River estuary.

The boat pilots, an experienced Arctic guide and an Inuit hunter from the nearby community of Arviat, Nunavut, proved exceptionally talented at keeping the boats at a constant speed of 15 kilometers per hour and, using handheld GPS units, along the grid lines. The field biologists, working in pairs as observer and recorder in each boat, ignored the waves and wind to scan for whales within 100 meters.

Getting ready to run the first survey line.

The beluga we encountered along our survey lines traveled exuberantly at multiple depths: swimming along the surface in pods of 10 to 20 or more in a straight line like a train of aquatic railway cars; just breaking the ocean's plane with a dorsal ridge; or swimming below our boats, white ghost-like shapes in the clear water.

One of our boats from a beluga's perspective.

Unlike a whale watching cruise that looks for groups of belugas, our research methodology required us to pursue a survey transect line to its end, even if no whales were visible. The potential value of this came from recording an absence of whales, as well as their presence. Repeatedly running the survey lines was a key to increasing the value of the data, and piecing together an understanding of how belugas use the Seal River estuary.

A ghost-like beluga swims in the silty freshwater at the mouth of the Seal River.

The day had started early. At 3:15 a.m. on July 5, the first full day of research, the boat pilot knocked on our doors with the good news that "we're go for weather." After bolting down hot Red River cereal, a mix of wheat, rye, and flax invented in Manitoba in 1924, we scrambled into multiple layers of warm clothes and rubber, and rolled the boats out of the polar-bear-proof enclosure. By 6 a.m., we'd made the long trip out to the start of the most distant survey line. A few minutes later, Kristin called out our first sighting: "Three pods of five animals each."

Eight hours later, we had finished six of the ten transect lines, but increasingly gusty weather forced us to head back to shore. While the pilots worked on the outboard motors amid swarms of mosquitos, the biologists returned to the Seal River Lodge to enter data from handwritten logs into laptops and plot it onto a digital map using GPS coordinates. After my first day of beluga surveys, I suspected I would never look at Arctic scientific research again without appreciating the sheer difficulty of studying these fundamental questions in such highly variable conditions. And most field work means sleeping in tents rather than a lodge.

The second and third survey days were much the same, only longer. Improving weather allowed us to stay out up to 12 hours and run all 10 transects. We encountered many belugas on the survey lines and saw even more outside of recording range. In the bright Arctic sun, adults were easy to spot as they flashed white while swimming or diving. The gray-colored babies and juveniles were only visible at closer range. At one point, looking up from the 100-meter observation zone, an experienced biologist estimated that she could see 350 adults in a 180-degree arc around our boat.

Beluga swims among fish.

On our way back to the lodge, we stopped to switch gas tanks close to a moving lane of dozens of belugas. A pod of five were attracted to the boat and swam around and under it repeatedly, their white bodies clearly visible underwater. I was still thinking about straight lines—and maybe a bit addled from a long day of waves and wind—when a fanciful metaphor came to mind. I imagined our survey transit lines in the water as the parallel lines of the staff on a sheet of music, and the beluga whales as notes swimming along, creating a melody that all of Western Hudson Bay could hear. 

Tides, Patience and Arctic Field Work

By Scott Highleyman
July 9, 2013

Seal River, Manitoba—"We'll have to head back," our boat pilot shouted over the wind. "We'll try again at 3 a.m. for the next high tide." He swung the open aluminum skiff around. Our survey crew of 10 and our bags of gear were dripping wet from rain and the waves that had kicked up as we loaded the boat on the afternoon of July 3 for the 25-mile journey from Churchill, Manitoba, up Hudson Bay to the Seal River. As we turned back, we rode alongside dozens of beluga whales coming into the Churchill River estuary with the high tide.

Just before reentering Churchill Harbor, we passed the diamond-shaped stone reminder of centuries of European travel and commerce in the region: Fort Prince of Wales. The star-shaped British fortification was built by the Hudson Bay Company in 1731 to defend against threats to the fur trade. In spite of its 35-foot-thick walls and 40 mounted cannons, the fort was surrendered without a shot to a French fleet 50 years later.

"Welcome to field research in the Arctic," said Kristin Westdal, marine biologist for Oceans North Canada, in response to the delayed departure. Westdal designed this year's research at the Seal River to answer fundamental questions about the beluga whales that return each summer to its estuary. The Seal estuary, and two neighboring estuaries on the Nelson and Churchill rivers, provide summer habitat for the Western Hudson Bay beluga whales. This population is thought to be the largest in the Arctic, comprising roughly 20 percent of the world's beluga. I joined the research team as another pair of eyes and hands.

Hudson Bay Beluga Project: Whale Distribution Survey

Last summer, the research team, including Westdal and Chris Debicki, an expedition leader and Nunavut project director for Oceans North Canada, tagged six belugas in the Seal estuary. The data transmitted by the whales over subsequent months allowed researchers to map their use of summer habitat as well as their migration north in the fall up the west side of Hudson Bay and to their winter home in Hudson Strait. The results—displayed in this interactive map provided important insights into the site fidelity of belugas in the Seal: other than one quick foray to the neighboring Churchill River by a single animal, the whales stayed in the Seal until they left these protected waters in the fall.

This year's research was designed to build on these insights with a boat-based survey of the Seal River beluga population to help collect baseline information on their distribution and abundance. Expanding on what we learned from the six whales tagged last year, the boat survey should provide a closer look at habitat use based on belugas' activities and density. Over the next five days, we'll be following specific “transects,” or routes, recording numbers, locations, and behavior of whales spotted from our boat, including whether the belugas are feeding, nursing, or resting. We hope to gain an understanding of what parts of the estuary are most important and why.

Chris Debicki of the Oceans North Canada research team, at sunrise on boat trip from Churchill to the Seal River.

The last beluga population survey, conducted in 2004, suggested that there are approximately 57,000 whales in this Western Hudson Bay group. Despite its size and importance, this population of beluga remains relatively under-studied. That's because increasingly scarce government research dollars often are spent studying Arctic animals in decline rather than healthy populations of whales, seals, caribou, waterfowl, and fish that are the core of the Arctic's natural wealth. But understanding the habitat and dynamics of healthy populations can help us devise conservation measures to maintain this abundance. This is essential to the ecosystem and to the more than two dozen Inuit communities in Canada whose ancestors lived on the shores of the Arctic Ocean for millennia before the earliest Europeans arrived.

A polar bear mother and her six-month-old cubs walk the Seal River tideline.

The working theory that emerged from last summer's research in the Seal estuary is that the belugas display great site fidelity in the summer and that there is little intermixing between estuarine regions. Our goal is to confirm this and discover more about habitat use in all three estuaries in the next two seasons of research. This will help inform potential recommendations to protect this habitat.

But first we need to get to the Seal River and the tides and the weather must cooperate. Early on July 4, we attempted the trip again. Two o'clock in the morning crept up too soon, but the diffused Arctic light in the pre-dawn at this latitude in summer gave us the visibility to reload the boat and shove off into the incoming tide an hour later. Now calm, the vast flat ocean soon gave us a clear view of the deep red sun nudging above the horizon.

Two hours of running time took us to the Seal estuary where we spotted our field work base, the Seal River Lodge. That was about the same time the black flies and mosquitos found us. Hot coffee and our first sighting of a polar bear and two cubs walking the rocky coastline followed, in that order, before we hit the bunks at the lodge for a nap. Later, we met to plan the first survey work.

Welcome to Arctic field work, I thought to myself.

Kristin Westdal (far left), marine biologist for Oceans North Canada, goes over study protocol with team after their arrival at Seal River Lodge.

Learn more about the Hudson Bay Beluga Project

Hudson Bay Beluga Project