To hope to survive, the two minke whales visiting Montreal must quickly find the waters of the St. Lawrence estuary, which are very different from those of the Old Port.
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The fresh water of the river, at the height of Montreal, does not in fact present any favorable conditions for rorquals: they are unable to feed there and the organisms which are in the water can stick to their skin and cause irritation.
Tests carried out on the whale which had been found dead near Montreal in 2020 had precisely made it possible to determine that it had an empty stomach and that the condition of its skin had deteriorated a lot after its arrival in the metropolis.
If the two minke whales seen in Montreal still seem in good health, their condition could deteriorate as their stay continues, warns Anik Boileau, researcher in veterinary sciences and animal welfare and co-founder of the Center for Education and Research Center of Sept-Îles (CERSI).
“The longer they stay in Montreal, the more we can observe a deterioration in their state of physical health, but also psychological. Their death is likely to be long,” she says.
“Being always on alert weakens you,” says the researcher. As long as one of them cuts, there is an increased risk of infection. Stress really causes global degradation [de la santé].”
Irritations caused by organisms can also be a source of additional stress which could weaken their immune system.
What can we do?
The Group for Research and Education on Marine Mammals (GREMM) indicated that no intervention was planned to relocate minke whales. As it is not an endangered species, the organization believes it is best to leave individuals the freedom to decide when to leave, to “let nature take its course”.
“The welfare of the animal, as well as the cost, logistics and chances of success of an intervention, are also considered” in the decision-making concerning a possible intervention, can we read on the GREMM website .
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Anik Boileau regrets this decision by the GREMM. “It sends a mixed message to the population,” she said. There is a societal consensus that we want to save marine mammals, but we are doing nothing to save these two individuals.”
Although she agrees that capture and relocation are not an option, in particular because of the stress that this could represent for the whales, she believes that the situation deserves more attention. .
She suggests placing a hydrophone that would emit sound frequencies, like those emitted by minke whales, to attract the two visitors to the right path. An “inexpensive” method that has already worked with gray whales, notes Anik Boileau.
Not because of climate change
How to explain that in two years, a humpback whale and two minke whales undertook the journey to the big city? Hard to say, argues Anik Boileau. She nevertheless puts forward a few hypotheses to explain their presence.
“There may be chemical signals in the water that can attract certain individuals. Or they detect sound frequencies that resemble those of schools of fish,” she says.
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But one thing is certain: climate change has nothing to do with it. “I do not see an explicit link between climate change and the arrival of these individuals. I rather have the impression that there is a specific factor in this place [du fleuve qui explique leur visite]», says Anik Boileau.
Human activity, however, could be responsible for these visits.
“The fact that there have been three of these events in two years tells me that we should do more research on this to try to understand the phenomenon and thus protect these species. It is our responsibility, as researchers, knowing that human activity has such a great impact on nature,” says the researcher.