Belly Up!
Over the last few days, the MICS team and their collaborators witnessed whales turned on their backs on three occasions, but in very different circumstances. Summary of a week filled with whale bellies!
Lunge feeding frenzy
Now that the team is trained and that two of our boats are ready, we go out at sea every time the weather permits, but we are seeing mostly minke whales. We take time to photograph them and document their behaviors, which includes spectacular lunge feeding maneuvers to capture schooling fishes like capelin and sand lance. To surprise, corral, and catch their prey, they quickly lunge with their mouth open, above or near the surface, with a variety of body orientations that are vertical, at oblique angles with the surface, on their sides, or upside down as a ventral lunge. We can then briefly see their pectoral fins, flukes, inside of their mouth or even their ventral pouch filled with water and fish. It makes for a very impressive show that can sometimes be observed in shallow water, just a few hundred meters from the beach.
A minke whale lunge feeding to catch a school of capelin. © MICS photo
A drifting minke whale
On the first outing of the season, on July 4th, we found a dead female Minke whale drifting on her back just south of île Nue. The carcass was fresh with only the tongue starting to become bloated from decomposition gases. The skin was in good condition so we were able to document a few scratches and superficial injuries. Because it is difficult to make an in-depth examination of a dead whale at sea, we took a few pictures and videos before letting it drift. Even if it was a sad and morbid encounter, the interns enjoyed being able to see a minke whale up close instead of from afar and for only a few seconds at a time!
On July 8th, we received information that the carcass had beached near the town of Magpie. Two team members went to take measurements and tissue samples. The exact cause of death could not be determined, but no evidence of a ship strike or rope entanglement was observed. Many onlookers gathered nearby and our team explained that the public must stay away from marine mammal carcasses and that it is illegal to remove any parts. Bacteria and parasites in the decaying tissue can make humans sick, and the dead animal must be intact for scientists to examine it and record as much information as possible. When a marine mammal is in distress or a carcass is found, please contact Urgences Mammifères Marins, just as the residents of Magpie thankfully did.
The same carcass has since been observed adrift again near Île du Wreck, about 3 nautical miles southwest of Longue-Pointe-de-Mingan. It could decompose at sea and sink, or get beached again somewhere else, depending on the action of winds and currents. Also, a dead whale can swim! Even a slight swell can agitate the tail up and down to a point where the whale moves forward. Who knows where it will end up?
The carcass when it was first observed, on July 4th. The animal is on her back and the tongue is bloated. © MICS photo
Flipper slapping fright
On July 10th, Pierrot Vaillancourt, the captain of a Parks Canada boat working in the Mingan Islands area, contacted MICS to report a humpback whale showing unusual behaviour south-west of Grande Ile. The animal was swimming on its back, seemingly in distress, and was not diving or showing its flukes, as is typical for this species. Cpt. Vaillancourt and his crew were worried that the whale was entangled in fishing gear, or was having difficulty for some other reason. After examining pictures from Vanessa Ward, a crew member, and talking with Cpt. Vaillancourt on the phone, the MICS team came to the conclusion that the animal was showing an uncommon, but well documented behaviour of humpback whales called “flipper slapping”. This behaviour involves a whale rolling on its side or back while at the sea surface, and then slapping the surface with its flippers (pectoral fins). We can’t say for sure what is the function of this behavior but evidence suggests that it could be a form of communication, a reaction to boat presence, play behaviour, or another behaviour that is still unknown to researchers. That individual was not seen in the area again, so it is probable that it continued on its journey elsewhere. In the end, Cpt. Vaillancourt and his thoughtful crew had the right idea when they contacted researchers as soon as they had a doubt about the well-being and safety of the whale. We were concerned about the idea of finding a second animal either dead or in distress over the course of a few days, but it was fortunately a false alarm!
Two humpback whales flipper slapping in Gaspésie. They are not calling for help! © René Roy
We’re still waiting for larger whale species to show up en masse in the Mingan Archipelago. Our collaborators further down the North Shore, Jean-Marie Jones and Ross Fequet, both commercial fishermen, say they have seen fewer whales than usual. In Gaspésie, René Roy only saw two or three blue whales moving quickly through the area, and few fin whales, although it’s already late in the season. Several humpback whales were seen in Gaspésie, near Sept-Îles and Baie-Comeau, and higher up in the estuary, including possibly two mother-calf pairs. Climate change and the lack of ice in the St. Lawrence last winter could partly explain the lower numbers of cetaceans observed so far this summer.
The team at MICS is now working at identifying whales from pictures we are receiving. In addition to other well-known individuals such as females Cédille (H144), Fleuret (H009) and Tic Tac Toe (H509), we were pleased to see that male Siam (H007) is still alive and kicking. He was one of the first whales photographed in the late 1970s by researchers working for Fisheries and Oceans Canada. Such information is valuable to evaluate population structure and migratory habits of individuals, and shows once again the importance of continuing long term studies about cetaceans in the St. Lawrence.