Zodiacs and Crossbows: I Spent a Day Chasing Whales to Learn How to Study Them
Right whale sightings are up on Canada's East coast. Nobody knows why.
Image: Mingan Island Cetacean Study
Biologist Kate Gavrilchuck advanced to the bow of the zodiac and loaded her crossbow as the boat navigated the rough waters of the Saint Lawrence River, which feeds into the Atlantic Ocean on Canada's East Coast.
"Be careful! One whale is right near the boat," Gavrilchuck shouted to her crewmates, who were struggling to keep the vessel steady in the meter-and-a-half swells. "Veer to the right!"
Suddenly the loud exhale of two humpback whales, which can weigh almost 80,000 pounds each, sounded out as they broke water alongside us, the spray from their spouts quickly blown away by the 40 km/h wind gusts. Gavrilchuck recognized one of them, which she called "Tracks," by sight.
"Tracks is the whale on the left," she yelled. As the boat veered to portside, she brought the crossbow to her eye and took aim, pointing it right at Tracks.
The whale was due to be biopsied.
The non-profit Mingan Island Cetacean Study (MICS), which keeps a research station in Longue-Pointe-de-Mingan, Quebec, on the Gulf of Saint Lawrence, is interested in whales—blue whales, especially, but other species, too. This summer out on the storied Canadian river, which links the Great Lakes to the Atlantic, has provided them with more questions than answers, and some new mysteries to solve. They're seeing fewer baby humpbacks and fin whales in the area, for one thing. Yet sightings of endangered North Atlantic right whales are suddenly, and inexplicably, on the rise.
Founded in 1979 by Paris-born biologist Richard Sears, the MICS is recognized as the first organization to undertake long-term studies of the blue whale, the largest animal on Earth. A major player in a collaborative project that succeeded in satellite tagging and recording the full winter migration of a blue whale in the North Atlantic for the first time, in 2014, the group's findings have been instrumental in understanding the movements and distribution of this enigmatic and still under-studied species, which is now designated as "endangered."
One of the MICS' main research tools is the biopsy performed by launching a modified arrow from a crossbow to collect a small tissue sample as the animal surfaces to breathe. After removing a small plug of its skin and blubber, the arrow bounces off the whale and floats in the water, where it can be retrieved. (This technique is approved by Fisheries and Oceans Canada.)
From that little piece of flesh, scientists can glean all kinds of information, including the animal's sex, what sorts of prey it consumes, and which contaminants are in its body—which in turn describe pollutants present in the animal's habitat. Biological sampling can complement other research methods to help scientists understand the social structure, reproduction and even the genealogy of each species.
As we bounced across the rough waters off Anticosti Island, a buzzing sound rang through the air. It was Gavrilchuck's arrow flying towards Tracks, the humpback whale, connecting on the first attempt. The arrow bounced off Tracks' side and floated in the water as the whale submerged.
After plucking the arrow from the waves, Gavrilchuck carefully withdrew a two-centimetre long, black-and-beige piece of skin and blubber and placed it in a vial inside a red thermos, where it would stay chilled. The sample would be processed and stored in the MICS laboratory, then sent away for genetic and hormonal analysis.
Over the past few seasons, information from biopsy samples, combined with photo identification of individual humpback and fin whales, has allowed the MICS scientists to notice a troubling trend. Since 2011, they haven't observed many sexually mature females in the company of calves. This year, only four humpback mother-calf duos have been seen in the estuary by the MICS, they told me, although approximately 30 mature females have been identified—a reproduction rate of close to 10 per cent, explained research coordinator Christian Ramp. While it's hard to give a firm number of how many calves were seen prior to 2011 (the numbers can fluctuate), in a good year, the team might observe 12 to 18 different calves, he said. That's a worrying drop.
"Because whales are long-lived animals, long-term studies like ours are necessary"
These scientists haven't observed one single fin whale calf in the estuary this year either, although approximately 30 mature females have been sighted, he added. Tracks is one of the many female humpbacks to have been observed without a calf this year, and the team hopes to find out why.
Robert Michaud, president and director at the non-profit Groupe de recherche et d'éducation sur le mammifères marins, a marine mammal research group that also operates in the Saint Lawrence, says that he suspects his organization is witnessing the same trend in other parts of the estuary. Causes of a seemingly low reproduction rate will be hard to confirm, he added. And they might also be different for both species.
That same day, out on the Saint Lawrence and far off on the pale-blue horizon, the MICS team spotted the V-shaped spout that is characteristic of the rare North Atlantic right whale. They raced against the swells to reach it, preparing their cameras as the boat rushed over the waves.
The team's most utilized research method is photo identification. The station, which is the official curator of the North Atlantic blue whale catalogues, is home to thousands of whale pictures, some of them in black-and-white. Researchers sort through newly captured photographs to make matches with older ones by comparing the whale's' skin pigmentation patterns, scars, and other unique characteristics, like fluke and fin shapes. A match can reveal important details about migration and lifespan—like when a specific blue whale was photographed near Pico Island in the Portuguese Azores in 2014, and matched with a photograph snapped across the Atlantic near the Mingan Archipelago, on the east coast of Canada, some 30 years earlier.
That day on the Saint Lawrence, the zodiac reached the right whale just in time to photograph it graciously lifting its large black fluke high out of the water, then diving deep. These pictures would be sent to the New England Aquarium in Boston, Mass., where the North Atlantic right whale catalogue is based.There, scientists might be able to identify the individual animal by matching it against other known whales in the collection.
Decimated by whaling, the current North Atlantic right whale population (which was estimated at 465 animals, as of 2011) is protected in both Canada and the US. The MICS team had spotted only four since early 2014, and none at all for a few years prior, said Ramp. So it's surprising that, this year alone, the MICS has seen 20 North Atlantic right whales. Total reported sightings in the Saint Lawrence are close to 50, he continued. Nobody knows why, exactly, there are suddenly so many whales here this year.
"These whales spend much of their lives aggregating in areas of high plankton concentration," explained Charles Mayo, senior scientist and director of the right whale ecology program at the non-profit Center for Coastal Studies in Provincetown, Mass. "I imagine that if we could get the best profiles of the Gulf of Saint Lawrence right now, we'd find that there is an unusual concentration of their primary food, which is copepods," a type of small crustacean, he added.
Mayo stressed that it is possible for whales to roam over very large areas, sometimes hundreds of miles, in search of food. The whales currently in the Saint Lawrence are likely the same ones previously identified in areas like the Bay of Fundy or the Gulf of Maine, he added.
Shifts in oceanic currents and other environmental variations influenced by climate change could potentially be contributing to their sudden increased presence, Ramp added.
More whale sightings in the Saint Lawrence sounds like a good thing, but it could mean trouble for them. Many sightings are occurring in maritime shipping lanes. Measures have been enacted to reduce ship strikes with right whales in other Canadian habitats, including New Brunswick and Nova Scotia, said Moira Brown, a senior Right whale scientist at the New England Aquarium.
"More research is needed to better define where right whales aggregate in the Gulf, to identify potential critical habitat and to find out which ships are using the area," said Brown. Several groups, including the MICS, relay their information about sightings to the shipping industry, she said.
As the winds increased, blowing blustery waves over the Saint Lawrence, the MICS team decided to call it a day. They photographed one more whale, a finback, on the wavy ride back to port.
"Because whales are long-lived animals, long-term studies like ours are necessary," said Sears, who is planning another expedition to tag blue whales off the coast of Gaspé in September.
This type of study could eventually help explain why humpback and fin whale calf sightings are much less common in the Gulf since 2011—while endangered right whale sightings seem to be more common. In the process, scientists might make some new discoveries about the effects of climate change and other pressures, anthropogenic and otherwise, that are affecting these animals. Even after almost 40 years of research with the MICS, Sears said, "there is still a long way to go."
Image Above: A North Atlantic right whale surfaces in the Gulf of Saint Lawrence on August 14, 2016. This whale is one of 20 North Atlantic right whales seen in the Saint Lawrence by the MICS this year. Image: Mingan Island Cetacean Study