The North Atlantic right whale regularly migrates to Canadian waters in the summer and fall to feed on zooplankton which aggregate in deep channels and basins of the western Scotian Shelf and Bay of Fundy. In recent years, researchers have noticed that sightings of this species have been declining in the Bay of Fundy, a key whale feeding and nursery ground.
Declining populations requiring increased data collection
Scientists estimate that the North Atlantic right whale population size is somewhere around 500 individuals, though there are significant uncertainties around this number. Their rarity presents an obstacle to those hoping to observe them for research purposes. To find these elusive and endangered whales, researchers from Dalhousie University, in collaboration with the Ocean Tracking Network and others with the Woods Hole Oceanographic Institution (WHOI) and the Marine Environmental Observation Prediction and Response network (MEOPAR), are using Slocum gliders equipped with devices that can “listen” and record the positions of whale calls. These autonomous robots are helping scientists detect right whales across the entirety of the Scotian Shelf and in the Gulf of St. Lawrence.
Autonomous underwater robots play the role of data collectors
Slocum gliders can travel thousands of kilometres for months at a time. During their journey through the ocean, gliders quietly collect valuable data on marine ecosystems using a suite of instruments that measure water properties and capture abundance of microscopic organisms. The gliders also pick up on whale calls – these detections are sent back to OTN and MEOPAR labs at Dalhousie in near real-time, informing researchers about the whereabouts of whales.
In the summer of 2016, two Slocum gliders were launched at the same time in the Northwest Atlantic Ocean to determine if right whales were using areas of this region. Researchers discovered that this species has been appearing near the Gaspé Peninsula, possibly in search of food. This information suggests the area might be one of the animal’s critical feeding habitats. Prior to this project, right whales had only been sighted sporadically near the peninsula.
Why track whales?
Locating North Atlantic right whale habitats and understanding movement patterns is helping reduce ship strikes and fishing gear entanglements, which are the greatest threats faced by these 60-tonne, slow-moving mammals. Understanding where Canada’s great whales are located will help minimize the impact of these and other harmful human activities while providing government researchers with the scientific basis to establish protected areas around sensitive whale habitats.
The Dalhousie-based team, in collaboration with the U.S.-based WHOI, will continue using Slocum gliders to track North Atlantic right whales again this summer.
To stay up-to-date on the Whales, Habitat and Listening Experiment (WHaLE) Project, and see locations of Canada’s whale populations, visit the Canadian Wildlife Federation’s website and blog this summer where content will be updated throughout the 2017 research season.