A recent research study has revealed that critically endangered North Atlantic right whales are now engaging in surface feeding at night, which is increasing their vulnerability to collisions with boats. The study, recently published in the peer-reviewed journal PLOS One, highlighted the nighttime surface feeding behavior of North Atlantic right whales, offering valuable insights to mitigate fatal collisions between the whales and vessels.
Lead author of the study, Jay Kirkham, a Ph.D. student at Dalhousie University in Halifax, collaborated with the U.S.-based non-profit Ocean Alliance to attach tags to 23 right whales in the Shediac Valley, located in the southern Gulf of St. Lawrence. The Shediac Valley serves as a seasonal feeding ground for a segment of the North Atlantic right whale population, estimated to be around 384 whales.
The tags utilized by the research team recorded video footage and tracked the movement patterns of the whales, providing essential data on their feeding behavior. Kirkham utilized the video recordings to observe the whales’ feeding behavior during daylight hours.
According to Kirkham, these observations were instrumental in training a machine learning algorithm to identify right whale feeding activities at night when visual identification was not feasible. The findings indicated that the whales are feeding at similar depths as large vessels during the night, heightening the risk of collisions.
While North Atlantic right whales typically feed near the ocean floor during the day, Kirkham explained that they ascend in the water column at night to pursue their primary food source, zooplankton. This behavior places them in close proximity to passing ships, increasing the likelihood of collisions.
Collisions with vessels and entanglements in fishing gear are the primary causes of mortality among the North Atlantic right whale population. The insights from this study could aid in the development of conservation strategies for the protection of these whales.
Current protection measures for the whales are overseen by Transport Canada and Fisheries and Oceans Canada. These measures include speed restrictions and a vessel exclusion zone in the Shediac Valley during the summer to mitigate collision risks. Despite these precautions, Kirkham highlighted that a significant portion of the tagged whales spent a considerable amount of their feeding time outside the designated exclusion zone, exposing them to potential ship traffic.
Transport Canada emphasized its commitment to protecting the whales through a surveillance program that employs visual and audio detection tools to prevent collisions. The department stated that it leverages the latest scientific research, monitoring data, and stakeholder feedback to enhance protective measures for the whales.
Fisheries and Oceans Canada mentioned that the study findings could inform tailored management measures to safeguard North Atlantic right whales, focusing on preventing entanglements in fishing gear and enforcing seasonal fishing closures. The collaborative efforts of these agencies and ongoing research aim to ensure the conservation and well-being of the critically endangered North Atlantic right whales.
