Narwhal derives from the Old Norse “nar” meaning “corpse” (Image: Paul Nicklen)
EVEN in the middle of August, Tremblay Sound in the Canadian Arctic is an inhospitable place. As the small plane descends, I get my first glimpse of our destination. Remote and desolate, it consists mostly of piles of rocks and a little scrubby vegetation. During my two-week stay it will be cold, wet and windy almost all the time. Nobody comes to Baffin Island to get a tan.
Nevertheless, this is the third summer running that Jack Orr from Fisheries and Oceans Canada has visited and, together with a team of scientists, vets and Inuit hunters, he seems right at home. In no time at all they have transformed the site into a fully operational research station, complete with colourful sleeping tents, a kitchen tent and a science lab housed in a plywood shack. Finally, they set their trap. Having firmly anchored one end of a heavy-duty fishing net to the shore, Orr jumps in a boat and crosses the narrow inlet so he can sink the other end to the seabed with a bag of rocks. Six buoys keep the upper edge of the net afloat to create a hanging curtain. All we can do now is await our quarry. Its scientific name is Monodon monoceros, which derives from the Greek for “one tooth, one horn” in reference to the males’ spiralled tusk, which can extend up to 3 metres. Many people simply know these creatures as sea unicorns.
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There are some 90,000 narwhals in the frozen northern seas. A small population lives off the coast of Svalbard, Norway, but most inhabit seas around Greenland, or are found in the northern reaches of Hudson Bay and in the Canadian high Arctic. The Baffin Bay population is one of the largest. Each summer, hundreds of narwhals return to these fjords and inlets. Orr and his team aim to catch nine of them as they swim past, and fit them with satellite transmitter tags.
“4.1 metres – Average size of a male – Females are smaller at 3.5 metres”
Orr is a veteran of this research, having tagged 300 whales over the past 30 years, mostly narwhals and belugas. It is hard, unpredictable, time-consuming work, but it is worth the effort to better understand this elusive animal. Narwhals are particularly tricky to study because they spend each winter in the dense Arctic pack ice, in complete darkness. Satellite tracking is invaluable in efforts to learn more about them.
“Narwhals spend all winter in the dense Arctic pack ice, in complete darkness”
Another researcher, Mads Peter Heide-Jørgensen from the Greenland Institute of Natural Resources has been studying narwhals for two decades. Using satellite tracking he has found . Year after year, each group undertakes the same migration in the spring and the autumn, moving between its winter feeding areas in the pack ice and coastal summering grounds (see map). The animals Orr studies leave northern Baffin Island in the autumn, migrating south to the Davis Strait where they spend the winter feeding on Greenland halibut, before returning the following summer. “They will go to the same places where they always go because they are programmed to do so,” says Heide-Jørgensen.
Narwhals are experts at navigating and surviving in the extreme Arctic environment. In the winter, they traverse the pack ice . “I am mesmerised when I see how fast the ice changes,” says Kristin Laidre at the University of Washington, Seattle. “In just an hour, a lead can close or completely freeze but the whales somehow know. They detect the change, and they are very good at navigating these dynamic areas.” , with a record dive depth of 1800 metres, which may help them stay out of trouble.
“In just an hour, a lead can close or completely freeze, but the whales somehow know”
Even so, a sudden freeze can catch them out. Between 2008 and 2010, there were several reports of narwhals becoming trapped in sea ice in Baffin Bay, unable to surface to breathe. At first, scientists thought changing sea ice conditions might be to blame, but then they discovered that the incidents coincided with seismic surveys of the bay. Narwhals are highly sensitive to noise; hunters in Greenland have known this for centuries and approach them in kayaks because if they use boats with noisy outboard engines the whales disappear. Heide-Jørgensen believes that , causing them to return to their summering grounds where they became trapped in the fast-freezing ice that now covered the sea surface. He and Laidre are currently using acoustic recordings and heart-rate monitors to better understand how narwhals perceive sound and react to noise produced by human activities.
Baffin Island in August never gets dark. We work 24 hours a day in 3-hour shifts to watch the net and keep a look out for polar bears. Often hundreds of narwhals swim past, yet none are caught. Waiting for a whale to hit the net is our main activity: when one becomes entangled it is crucial that we act quickly so that it doesn’t drown. Bundled up against the cold, we watch and we wait.
“90,000 – Total number of narwhals – Conservation status is “near threatened””
In this meditative state, you notice things. The Arctic tundra is surprisingly colourful. There is bright orange lichen growing on rocks, yellow saxifrage and the tiny Arctic willow, the most northerly of all woody plants. The ground is also covered in animal bones, some seemingly very old. Bowhead whale remains, narwhal skull fragments, the pelvis of a ringed seal and caribou jaws and antlers dot the landscape like unexpected artworks.
At one point, a storm hits and we have to pull in the net – it would be unsafe to try to tow a whale to shore. The wind is so violent I am worried it will rip my tent. There is more waiting, but this time for the storm to pass.
“5-20 – Group size in winter – In summer groups can exceed 1000”
The Arctic is changing rapidly. Since 1979, about 2 million square kilometres of year-round sea ice has melted. At this rate, the Arctic Ocean is expected to be ice free in summer by around 2050. Can the narwhal survive in a world without ice?
It doesn’t look good. A study comparing the sensitivity of different Arctic marine mammals to the effects of climate change , reliance on sea ice and specialised feeding behaviour. One problem is that the loss of sea ice during the summer is opening new hunting territory for orcas. With their large dorsal fins, orcas are poorly adapted for swimming in ice-covered waters, but areas in the eastern Canadian Arctic that were once off limits to them are now accessible. That puts narwhals at increased risk of becoming dinner.
A second concern is how the loss of sea ice and warming temperatures will affect the fish the narwhal eats. In Hudson Bay, for example, warming has led to an increase in capelin and a decrease in Arctic cod over the past three decades. żěè¶ĚĘÓƵs don’t know if the narwhal, which feeds on only a handful of species including Arctic cod, can switch to other types of prey. . Comparing the diets of narwhal populations in Baffin Bay, northern Hudson Bay and the east coast of Greenland, a team led by Cortney Watt at the University of Manitoba in Winnipeg, Canada, found they eat different food types depending on where they are. “This suggests they may be able to adapt their foraging behaviour to the changing prey availability,” she says.
“3.1 – metres Maximum tusk length – It is actually a hollow canine tooth”
Sea ice loss also opens up opportunities for industrial development and commercial shipping in the region. Peter Ewins at WWF Canada and his colleagues have reported – narwhals, belugas and bowhead whales. For example, a recently approved iron mine in northern Baffin Island is expected to bring more shipping traffic into one of the most important summering areas for narwhals. Ewins is particularly concerned about oil pollution, ship strikes and acoustic disturbance. “There is a major likelihood of disruption to these habitats, which may become totally unsuitable to these animals,” he says. The authors suggest a variety of measures to mitigate the impacts of human activities on whales, including careful planning of shipping lanes, the prevention of industrial activity in critical areas and regulation of seismic surveys.
After days of waiting, netting a sea unicorn seems like an impossible task. We play cards, wait, drink coffee, wait, drink more coffee and wait some more. Despite the tedium, it can be nerve-racking. Because narwhals are often captured in the middle of the night, we never really sleep, always ready to spring into action as soon as we hear the alarm.
Eventually it comes. First the horn and then: “Whale in the net!” We all frantically pull on our dry suits, ready to jump into the freezing water. Three people hop into a boat and race to the end of the net to cut the anchor rope. Another boat crew pulls the net up to bring the whale to the surface so that it can breathe. A shore crew then manoeuvres the animal into shallow water where the real work can begin.
“5 – 6 months – Average time a narwhal tag transmits data – The record is 14 months”
We have caught a large female, 4 metres long and anxious to get back to her calf. It’s a team effort to calm and control her. While Orr attaches the tag to her dorsal ridge using two nylon pins, others collect a small piece of skin, which will undergo genetic testing later. The researchers monitor her heart rate, take blood and blowhole samples, record body measurements and assess her overall health, noting scars and signs of moulting. “We go as fast as we can, and we put a lot of effort into ensuring that there is as little stress to the animals as possible,” says Orr. In less than 30 minutes she is ready to return to her calf.
More information is needed to plan for the long-term conservation of these extraordinary animals, but narwhals are tricky to study. “It takes years to learn even a small thing,” says Laidre. And with changes coming so fast to the Arctic, time is of the essence. “We need the answers now but it takes a while to get them,” says Heide-Jørgensen. Even with satellite tracking there are problems. One tag from a female caught in Tremblay Sound was still transmitting data 14 months later, but that is highly unusual; on average the tags last five to six months. We caught five whales during our trip, fewer than Orr had hoped for. One of the tags malfunctioned within the first few weeks, and contact was lost with the remaining whales after about four months. This is the reality of using high-tech equipment in the Arctic. Anything can happen, from programming glitches to tagged narwhals being killed by hunters or orcas.
“1800 metres – Maximum dive depth – They are among the deepest diving whales”
As scientists work to understand the mysterious narwhal, it remains a paradox. Despite being long-lived – they can live at least 50 years – slow breeding and lacking genetic diversity, the species is remarkably resilient. It has survived for thousands of years in an extreme environment and through several periods of dramatic flux. But how much more can the narwhal take?
How the narwhal got its tusk
For centuries people have wondered why male narwhals have a tusk. Today, most scientists see it as a sexual trait used to determine social rank and compete for females – much like the antlers of a stag. Another idea, suggested by Martin Nweeia at Harvard University, is that it acts as a sensor, detecting chemicals associated with prey, ice formation and salt concentration. Traditional explanations are often more colourful, and when I spoke to Nweeia he recounted a legend he had learned from Elisapee Ootuva, an Inuit elder from Baffin Island.
One day, a polar bear approached a house occupied by a woman, her daughter and her partially sighted son. The woman told her son to shoot the bear and, with help from his sister to position his bow and arrow, he struck it through the heart. His wicked mother pretended he had missed and, that night, while she and her daughter ate fresh bear meat, her son dined on dog food. But later, his sister told him the truth.
The next day, an old man came to the house predicting that the boy would encounter a giant bird on the lake and was to climb onto its back. He did so and the bird took him underwater three times. Each time he came up, he could see more clearly, until his eyesight was restored.
That summer, a pod of beluga whales swam close to shore. When the boy grabbed his spear, his mother eagerly asked if she could help. Quickly, he tied the end of the line from his harpoon around her waist so that she could hold the speared animal. Then he harpooned the biggest whale in the pod. The beluga pulled. As the woman entered the water, her body bloated and she morphed into a narwhal, while her long hair spun into its spiralled tusk. “The legend has it that it is a good sign to see a narwhal in the midst of belugas because that’s the woman who was transformed,” says Nweeia.
This article appeared in print under the headline “Hunt for the sea unicorn”
