A recent research study indicates that critically endangered North Atlantic right whales have been observed feeding near the ocean’s surface at night, which raises their vulnerability to boat strikes. The study, released in the peer-reviewed journal PLOS One, showcases the nocturnal surface feeding behavior of these whales, offering valuable insights for preventing fatal collisions with vessels.
Lead author Jay Kirkham, a PhD student at Dalhousie University in Halifax, collaborated with the U.S.-based non-profit Ocean Alliance to attach tracking devices to 23 North Atlantic right whales in the Shediac Valley, located in the southern Gulf of St. Lawrence. This valley serves as a feeding ground for a segment of the estimated 384-strong North Atlantic right whale population during the summer months.
Kirkham utilized the data collected from these tagged whales, which included video footage and movement patterns, to analyze their feeding habits both during the day and night. He noted that while the whales typically feed near the seabed during daylight hours, they ascend in the water column at night to pursue their primary food source, zooplankton.
The study revealed that at night, these whales feed at a depth that coincides with that of large vessels, heightening the risk of collisions significantly. Kirkham emphasized that collisions with ships and entanglements in fishing gear pose the most significant threats to these whales’ survival, underscoring the importance of implementing conservation strategies based on these findings.
Current protection measures for the North Atlantic right whale population are overseen by Transport Canada and Fisheries and Oceans Canada. Fisheries and Oceans Canada highlighted that the study findings could aid in tailoring management strategies to safeguard the whales, focusing on preventing entanglements in fishing gear and enforcing seasonal fishing restrictions.
Transport Canada enforces speed limits and a vessel exclusion zone in the Shediac Valley during the summer to minimize the chances of boat-whale collisions. However, Kirkham noted that a substantial portion of the tagged whales’ feeding activities occur outside this protected zone, exposing them to vessel traffic.
Transport Canada also operates a surveillance program dedicated to monitoring right whales using visual and acoustic detection tools to prevent collisions effectively. By leveraging the latest scientific research and stakeholder feedback, the department continuously refines its protection measures to ensure the whales’ safety.
Overall, these research findings offer critical insights that can inform targeted conservation actions to safeguard the vulnerable North Atlantic right whale population.
