A recent research study has discovered that the critically endangered North Atlantic right whales are engaging in nighttime surface feeding, a behavior that raises their vulnerability to boat strikes. The findings of this study, recently published in the peer-reviewed journal PLOS One, shed light on the feeding habits of North Atlantic right whales and offer insights that could aid in preventing fatal collisions between these marine mammals and vessels.
The lead author of the study, Jay Kirkham, a PhD student at Dalhousie University in Halifax, collaborated with the U.S.-based non-profit organization Ocean Alliance to attach tags to 23 right whales in the Shediac Valley, an underwater valley in the southern Gulf of St. Lawrence. This valley serves as a feeding ground for a portion of the estimated 384 North Atlantic right whale population during the summer months.
By utilizing tags that captured video footage and movement data of the tagged whales, Kirkham and his team observed the feeding behaviors of the right whales both during the day and at night. The research revealed that while the whales typically feed near the seafloor during daylight hours, they ascend higher in the water column at night in pursuit of their primary food source, zooplankton.
According to Kirkham, the study’s data showed that right whales and large vessels share similar depths during nighttime feeding, increasing the risk of collisions between the two. Collisions with ships and entanglements in fishing gear are identified as major causes of mortality within the North Atlantic right whale population, underscoring the importance of conservation efforts.
Current protection measures for the whales are overseen by Transport Canada and Fisheries and Oceans Canada. Fisheries and Oceans Canada emphasized that the study findings could help tailor management strategies to safeguard North Atlantic right whales, focusing on mitigating entanglements in fishing gear and enforcing seasonal fishing closures.
Transport Canada enforces speed restrictions 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 significant portion of the tagged whales ventured outside the exclusion zone during their feeding activities, exposing them to potential ship traffic hazards.
In response, Transport Canada mentioned its right whale surveillance program, which employs visual and audio detection tools to aid in the protection of whales against collisions. The department highlighted the use of advanced technologies and scientific research to inform and enhance protective measures for the whales.
The study’s insights can play a crucial role in shaping effective conservation strategies for North Atlantic right whales, offering hope for the preservation of this endangered species.