HALIFAX, Nova Scotia — A new study will help identify optimal locations, technology and scientific approaches to maximize the effectiveness of whale monitoring in and around a major Canadian shipping region with the goal of mitigating ship strike risk.
The study, led by Prof. Kim Davies (University of New Brunswick), uses autonomous underwater gliders and fixed moorings, both equipped with digital acoustic monitoring devices, to locate whales in the Honguedo Strait, between Anticosti Island and the northern Gaspé Peninsula in the Gulf of St. Lawrence.
Gliders listen to, and report, the calls of blue, sei, fin, humpback, and North Atlantic right whales in near real-time using technology developed by collaborators at Woods Hole Oceanographic Institution. It is one of the only systems in Canada that monitors North Atlantic right whales in near real-time, but local environmental factors can strongly influence glider “flight” and the efficacy of this and other systems which rely on detecting and differentiating whale sounds from other sources of noise. In addition, while the gliders represent no risk to vessel traffic, they can be damaged in a collision with a ship. So far, the gliders have proven up to the task, and are able to maintain their navigational path in this high current environment.
“The instruments deployed in early September have performed really well so far, and have detected fin, and sei whales in the Honguedo Strait. These data will allow us to measure the presence of endangered whales in and around the shipping corridor, and learn how best to use the technology to support ship strike mitigation efforts”, says Davies.
Slocum Gliders, manufactured by Teledyne Webb Research, move by changing buoyancy while short wings translate vertical motion into forward movement.
The glider will profile vertically between the surface and depths up to 200 metres, continuously recording acoustic data.
Autonomous Multichannel Acoustic Recorder (AMAR) moorings, manufactured by JASCO Applied Sciences, provide critical ground-truthing data for the gliders in high- and low-noise (e.g shipping) environments.
The international team, comprised of scientists from the University of New Brunswick, Dalhousie University, Ocean Tracking Network, Woods Hole Oceanographic Inst., JASCO Applied Sciences and Teledyne Webb Research, hopes that fine-tuning whale monitoring systems in the Honguedo Strait will help support dynamic management of these and other shipping lanes in Canada to reduce the interactions between marine mammals and vessels. Vessel strikes are one of the known threats to endangered whales in Canada, in particular the North Atlantic right whale.
Transport Canada is supporting the two-month mission during which the glider, deployed in the Gulf of St. Lawrence near Rivière-au-Renard on September 4, will complete 16-20 transects of a 65 kilometre section of the Honguedo Strait. A preliminary report may be possible in early 2020. Validated detections will be disseminated via automated systems, including the publicly accessible WhaleMap.