North Atlantic blue and right whales are disappearing from our waters: the blue whale (Balaenoptera musculus) has been listed as endangered on an international level, while the right whale (Eubalaena glacialis) has been named the most endangered large cetacean in the North Atlantic.
But our knowledge is limited. Most blue whale sightings in the North Atlantic have come from the St. Lawrence region, while right whale identification has generally been compiled within 80 kilometres of the eastern seaboard. So what happens when the whales venture out to sea? What happens in the Grand Banks or eastern Scotian Shelf? That’s what Richard Sears of the Mingan Island Cetacean Study, Inc. is determined to find out. The Canadian Wildlife Federation’s Endangered Species Program is giving $87,000 to Mingan Island Cetacean Study, Inc. to research the distribution, dispersal and numbers of blue and right whales in the North Atlantic.
The heavyweight of the whale group, the blue whale can grow up to 33.6 metres in length and live up to 80 years. Approximately 372 blue whales have had their photos snapped over the course of 21 years of research in the Gulf of the St. Lawrence. Of these, 40 per cent return to the St. Lawrence every year; however, the remaining 60 per cent are hard to account for. Researchers are concerned about the low numbers of blue whales in Canadian waters; some years see as few as 20 blue whales in the St. Lawrence. The question is why.
The population took an enormous hit between 1898 and 1951, when commercial whalers took 1,500 of 11,000 blue whales in the North Atlantic. While blue whales were given worldwide protection in 1966, researchers believe the low number of calves being born every year and the weak population numbers indicate that blue whales haven’t recovered from whaling. In addition, blue whales are now up against ship strikes, disturbance from eager whale watchers, becoming caught up in fishing gear, ocean pollution and climate change.
The Right Stuff
While these gargantuan creatures may seem invincible measuring 16 metres in length and weighing 80 tonnes, researchers estimate that the right whale could go extinct in approximately two centuries. The Committee on the Status of Endangered Wildlife in Canada reports that there are 322 identified right whales in the North Atlantic. When summer hits, right whales nurse, chow down and live it up in the Bay of Fundy, Roseway Basin and on the Scotian Shelf. While there’s been a great decline in the number of offspring produced every year since 1990, numbers from recent years have researchers scratching their heads: 2009 saw 20 more calves born than in 2006. Nevertheless, the birth rate of North Atlantic right whales is significantly lower than their Southern comrades. Researchers have a laundry list of culprits including injury and mortality from ship collisions, entanglement in fishing gear, a decline in the availability of food, changes in the way they use habitat, disease, marine toxins, genetics and climate change.
How Sears’ Research Fits in
Considering that most right and blue whale research has been conducted close to home, Sears and his team set out to sea from St. John’s, Newfoundland to survey the whales in the offshore shelf-edge waters of the Grand Banks and Laurentian Channel between July 21 and August 11, 2010.
Researchers have long speculated that blue and right whales regularly visit the Grand Banks en route to the St. Lawrence, however, no one has ever tested the theory until now. The verdict? It seems we can tentatively rule out the Grand Banks as another summer habitat for blue and right whales. Sears and his team did not come across any right whales and found only four blue whales in the area.
They did however find a number of other cetaceans in the Grand Banks including fin whales, minkes, humpbacks, Northern bottlenose whales, as well as porpoises and dolphins. The researchers also photo identified an entire pod of killer whales.