Underwater Sound and its Effects on Beluga in the St. Lawrence Estuary

Marine noise comes from a wide variety of sources, whether they originate from natural or human activity. For example, this can include industrial activities taking place near or directly in the water, the presence of harbour activities, and traffic from merchant ships and other vessel types (pleasure craft, whale watching cruises, fishing, research, etc.). Natural noise can also be an issue, such as sounds from the marine species themselves, ice cracking, wind, waves, rain, thunder, earthquakes, and others.

To accurately assess the potential impacts of underwater sound on beluga in the St. Lawrence Estuary, a five-year research program was implemented by a Fisheries and Oceans Canada science team, as part of the Oceans Protection Plan. The ensuing findings will be used to:

• map the acoustic quality of the beluga’s environment;
• determine the areas and times with the highest or lowest probabilities of impacts on the beluga’s survival and the recovery of this protected population under the Species at Risk Act in Canada; and
• support the implementation of measures to reduce noise based on scientific knowledge.

Important measures have been implemented for this program, such as:

• deployment of an acoustic observatory that includes 10 recording stations to map underwater sound in the beluga’s habitat between Île aux Coudres and Île du Bic;
• modelling of the sounds transmitted by vessels and their potential impacts on the beluga;
• air surveys of the beluga, as well as series of detections and localizations of animal sounds at the 10 acoustic observatory stations; and
• combined deployment of acoustic recording tags placed on belugas using suction cups and water-drifting acoustic recording buoys in order to better understand the animals’ reactions to sound exposure.

Through major efforts as part of the Oceans Protection Plan—a $1.5 billion plan—the whale protection initiative will make it possible to implement concrete measures to improve responsible navigation and the protection of Canadian waters, ecosystems and marine habitats. Transport Canada, Fisheries and Oceans Canada, Environment and Climate Change Canada, and Natural Resources Canada are working with Aboriginal communities and relevant stakeholders to protect endangered marine mammals in Canada.

Yvan Simard
Science