Five Questions for Richard Sears
Why are humpback whales moving into the Gulf and estuary of the St. Lawrence, while blue whales seem to be moving out? Could it be an unexpected result of the collapse of cod stocks around Newfoundland and in the Lower St. Lawrence? With answers to these questions is Richard Sears, a noted whale biologist and founder of the Mingan Island Cetacean Study (MICS), a non-profit research organization active in the Gulf of St. Lawrence and dedicated to ecological studies of marine mammals.
Richard Sears, founder of MICS (Photo courtesy of MICS)
George Tombs: The blue whale is the largest animal that ever lived on Earth. Adults can reach 30m in length. What a fascinating species! Could you describe the migration route of the blues of the St. Lawrence estuary and Gulf?
Richard Sears: In the western North Atlantic, we are not certain where they migrate to in winter, but we do know that some are seen or heard by hydrophone between Bermuda and the US coast , some offshore of New York and New Jersey, others off Newfoundland and Nova Scotia. In the eastern North Atlantic we know that blues can migrate between Iceland and NW Africa and the Azores.
George: What do these blue whales live on?
Richard: They feed on what is called krill, which are small shrimp-like animals mostly of the Euphausiid family. Are their numbers stable, increasing or decreasing? In the western North Atlantic I would guess that numbers are stable and may be increasing, but at a very low level, which may be a problem for this group of blue whales as far as returning to a strong population.
A humpback whale spotted by the Mingan research group. (Photo by Fred Paquet, MICS)
George: Since the early 1990s, you have seen blue whales moving out of the Mingan area of the Gulf of St. Lawrence, whereas humpbacks have been moving in. Can you explain why?
Richard: In the early years at Mingan, we had a lot of blue whales – they were very regularly sighted there, from August on to November, and probably December – we weren’t there in December to see them. And then all of a sudden, by the early 1990s, most of the blue whales seemed to choose another place, for some reason. And there was no increased level of boat activity in that area, or anything of that sort, and actually fishing had decreased because the cod were disappearing. And I’ve been wondering why this happened. And then on top of it, some of the blue whales we had been seeing in Mingan didn’t just show up in the St. Lawrence estuary or off the Gaspé Peninsula – they vanished – about 20 or so animals that haven’t been seen again…. And we thought that as we increased our coverage of the western St. Lawrence, from the Gaspé and the North Shore, we would have a chance of finding these animals. Well, we haven’t. So what happened? Either these animals all died from some catastrophic event – although I don’t think that is what happened. We know one of them died. Or they chose to go to another place for some reason. And interestingly enough, at that time humpback whales were starting to increase in the St. Lawrence, both in overall numbers and in numbers reproductively. Some seasons we have 16 calves. Finback whale calving has also been increasing. So there is a steady source of food for these animals. We know that humpbacks and finbacks will eat krill, but they will also eat fish – capelin, sand lance, herring and squid. Interestingly enough, studies suggest the amount of capelin is very solid off the Lower North Shore, and probably sand lance. So, did the blues leave because the cod that used to devour these other species of fish were suddenly removed from the water column – and the capelin and sand lance and other species increased as a result? And because the capelin feed on krill, have they been hammering the krill in that area?
As blue whales move out of the Gulf of St. Lawrence, humpbacks like this one are moving into the area. (Photo by Fred Paquet, MICS)
Could the blue whales have found too much competition from the fish to have adequate access to krill themselves, and so they moved to other areas? And on the other hand, humpbacks found the St. Lawrence to their liking, because there were greater quantities of capelin and sand lance and other species. Both the finback and humpback have benefited from this change in the water column and food chain. Anyway, this is something we would like to discover. It will take further research to answer your question.
George: Given that hunting whales is a thing of the past, what do you see as the main threats to whales now, and what actions would you like to see in order to protect them further?
Richard: The main threat to whales is posed by humans and by what we do by polluting with toxic chemicals. Acoustic pollution is also a huge problem given that noise has been increasing with regularity in the oceans due to seismic oil and gas surveys and shipping. A further threat is from overfishing, not to mention fishing gear entanglements, since some whales get caught in fishing gear and then die.
Puffins on île aux Perroquets in the Mingan archipelago (Photo by George Tombs)
George: I remember camping once with my family at Bergeronnes just northeast of Tadoussac, and during the night we could hear what sounded like very distant singing – almost like a party. As we listened to it, we could hear whales just off shore, ten metres off shore in the trench there, breathing and occasionally spouting. But we could hear this distant sound, in the darkness of night. And next day, we asked people what it was, and they said it was belugas that you can occasionally hear right at the surface, and they do stay a lot at the surface.
Richard: At night, I have been in bays along there, and you can certainly hear the breathing of all these different whales, which is impressive in the stillness of the night. Different animals breathe a little differently. Finbacks sound more like someone is blowing over the top of a bottle when they breathe in. But if you have humpbacks around, you could certainly hear humpbacks trumpeting or some of the sounds they make are very recognizable at the surface – trumpeting, sort of like elephants when they are annoyed, or just interacting among themselves. With blue whales, there is a sort of equivalent we have come to recognize. We call it “rumble breath.” It’s akin to the sound of a truck on airbrakes coming down a hill – a sort of “bububububub.” And I’ve noticed it’s in situations where females are being approached by males, and they are showing their annoyance – “get away from me, you bugger – I don’t want to have anything to do with you!” There are slowly emerging personalities from these blue whales, the more time we are able to spend with them. With humpbacks, you see their personality much more quickly. They let you know what they like and don’t like, they are much more vocal at the surface, or under the water using hydrophones, amongst themselves. They breach, in other words, they jump out of the water and they hit their flippers on the water: they are much more expressive. They are perhaps the more akin to us because they are so noisy. We are an incredibly noisy species. Almost everything we humans do is noisy. And the more you spend time on the water, the more you seek stillness, like your moment in Grandes Bergeronnes there, where you had a quiet evening camped out on the rock. Those are things we really need to seek out….
MICS encourages the general public to take part in whale research. (Photo by Fred Paquet, MICS)
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About MICS:
Founded in 1979 by Richard Sears, MICS was the first organization to carry out extensive long-term research of cetaceans in the Gulf of St. Lawrence. The principal study area is along the Québec North Shore in the Mingan Island/Anticosti region. MICS is best known for being the first organization to carry out long-term studies of the endangered blue whale (Balaenoptera musculus).
In order to fund their research, MICS invites the public to participate in ecological studies of marine mammals. Each year, MICS offers research sessions to the public from June to October in the St. Lawrence and during February/March in the Sea of Cortez. The purpose of these sessions is to help finance their research and to educate the public on marine mammal ecology while observing these animals in their natural habitat. The aim of MICS is not to offer just another whale-watch; they want you to have the opportunity to take part in and contribute to their research!
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If you would like to hear « Les Bergeronnes », Marie Frenette’s song in French about the St. Lawrence whales, click on this link:
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© Marie Frenette 2004
Marie Frenette (Photo by George Tombs)