Diving into the third dimension
Whales only spend 10-20% of their time at the water’s surface. This is often all scientists have to study them. In the St. Lawrence, scientists use satellite and radio telemetry. These techniques allow to study whales in their underwater world.
Ideal for understanding the details of a whale’s life and monitoring its movements over short distances.
Janie Giard and Robert Michaud, of the GREMM and Véronique Lesage, of the Maurice Lamontagne Institute (Fisheries and Oceans Canada), study several rorqual species using data recorders equipped with radio transmitters. Some transmitters, such as those developed by researchers at the Woods Hole Oceanographic Institution for a beluga project in collaboration with the GREMM, are fitted with a sound-recording device. Such transmitters are used to study the vocalization behaviour of belugas and their exposure to ambient noise.
Two techniques are used to attach tags to the backs of whales: poles and crossbows
Two deployment methods: pole and crossbow © GREMM
- Transmitter placement on a humpback whale using a pole; transmitter placement on a fin whale using a crossbow
- Video credit: © GREMM
Placement of transmitter (telemetry) on Tic Tac Toe, August 27, 2013 © GREMM
- Placement of transmitter (telemetry) on Tic Tac Toe, August 27, 2013 © GREMM
- Video credit: © GREMM
- 0:00 – 0:00 – Aboard the Bleuvet: Michel Moisan and Renaud Pintiaux of the GREMM, and Véronique Lesage of Fisheries and Oceans Canada. The team finds humpback whales Tic Tac Toe and Aramis.
- 0:06 – 0:06 – Approaching the two whales.
- 0:15 – Pole-assisted placement of tag onto the back of Tic Tac Toe: it’s a success! Aramis is nearby.
- 0:39 – Aramis is spotted first, then Tic Tac Toe, with the yellow and orange tag on its back. The signal is heard as picked up by the receiver.
- 0:54 – Throughout the monitoring, the crew collects data whenever the whale surfaces. Here, Véronique Lesage.
- 1:00 – The Parks Canada team, on board L’Alliance, conducts a prey census by means of acoustic monitoring, in the sector frequented by Tic Tac Toe.
- 1:05 – The tag falls off Tic Tac Toe’s back during a breach. Shortly thereafter, she is observed flipper slapping. The tag was recovered.
Satellite telemetry is ideal for studying the movements of a whale over long distances and to obtain information synopses on its activities over extended periods. However, this technique implies a number of challenges:
- Placing transmitters on animals in the wild which only surface briefly and which are often difficult to approach;
- High costs of this type of tag and subscription to a satellite communication system;
- Development of prototypes that do not cause injury to the whales;
- And the risks and uncertainties associated with attaching a tag to a smooth and hydrodynamic body moving through the water at high speeds and interacting with other organisms and obstacles!
Since 2009, a team composed of researchers from Fisheries and Oceans Canada, MICS and the Alaska Sealife Center has been using telemetry on blue whales in the St. Lawrence to document, from spring to fall, the animals’ movements, their utilization of known sectors and to discover new ones, including wintering grounds.