Assessing Changing Baleen Whale Distributions and Incidents Relative to Vessel Activity

Abstract

Baleen whales in the Northwest Atlantic Ocean (NWA) are increasingly affected by human pressures related to vessel activity, fisheries entanglement, and climate change. Vessel strikes and entanglement in fishing gear, in particular, often result in distress, injury, or death for these animals. These negative interactions or ‘incidents’ are consistently reported to marine animal response organizations throughout Atlantic Canada but have not yet been analyzed for scientific publication. Using all available incident reports, together with opportunistic sightings data, vessel activity data, and habitat suitability projections from species distribution models, I analysed areas where baleen whales are vulnerable to vessel-related incidents both now and in the near future. Current incident reduction strategies were also reviewed, and their present and likely future success was assessed based on my findings. Results suggest that cross-species areas of high current and future habitat suitability are strongly dependent on sea surface salinity and temperature and primarily exist in the Bay of Fundy, Scotian Shelf, Laurentian Channel, Flemish Cap, and Gulf of St. Lawrence. Areas where all species of baleen whales are vulnerable to incidents occur close to densely populated areas, around major shipping channels and fishing areas. Baleen whales may also be more vulnerable than expected to incidents involving small vessels. While some of these high-risk areas have mitigation efforts in place, they likely require new measures to ensure the safety of all species of baleen whale present there now and in the future.