Researcher Anik Boileau, director of the Centre d’Éducation et de Recherche de Sept-îles (CERSI), based in Sept-Îles, observed a pair of blue whales on August 9 off Port-Cartier. The two giants swam together in unison for two hours before separating and maintaining a distance of approximately one nautical mile for nearly three hours. “A very interesting observation for us as we study the social behaviour of these giants,” emphasized the researcher. In addition, she noted the presence of minke and fin whales that day, as well as 200-300 Northern gannets.

Rather solitary and nomadic, blue whales travel in pairs or in small temporary groups. In the St. Lawrence, the formation of stable pairs lasting a day or even several weeks is sometimes observed beginning in July. These pairs are most often male/female duos. According to the Mingan Island Cetacean Study (MICS) team, this association is believed to possibly be a precursor to the reproduction that takes place in winter.

The blue whale is a summer seasonal resident of the Gulf and Estuary, where it can sometimes be seen quite close to the coast. Sightings have been reported in recent weeks, including in the Escoumins-Tadoussac and Gaspé regions.

Observation of the Week - 11/8/2015

Marie-Sophie Giroux

Marie-Sophie Giroux joined the GREMM in 2005 until 2018. She holds a Bachelor’s degree in Marine Biology and a diploma in Environmental Consulting. As Lead Naturalist, she oversees and coordinates the team working at the Marine Mammal Interpretation Centre and writes for Whales Online and Whale Portraits. She loves to share “whale stories” with visitors to the CIMM and readers alike.

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