N.S. researchers use tracking technology to learn from ocean animals

Newborn Orca calf L121 swims with its mother, L94, off Westport, Wash., with the NOAA research ship Bell M. Shimada in the background on Feb. 26, 2015. (Candice Emmons / NOAA Fisheries)

HALIFAX -- Ocean researcher Nigel Hussey says the hardest part of tagging a giant Greenland shark isn't dealing with the carnivore -- it's keeping his hands in sub-zero Arctic water while he does the work.

Hussey tags animals from the high Arctic down to the tropics as part of his research with the Nova Scotia-based Ocean Tracking Network, which connects scientists to the movements and behaviours of animals around the world.

The latest issue of the academic journal Science features a paper by Hussey and his fellow researchers on advances in the field of aquatic animal telemetry -- where scientists tag an animal with an electronic device to monitor its actions from a distance.

Hussey says improvements in tracking technology mean scientists can go beyond observing an animal's location. He says researchers can now use "animals as oceanographers."

"You can actually use the animals to monitor their own environments," said Hussey, a research associate at the University of Windsor.

Rather than having to go out on a ship and drop down equipment to measure ocean qualities such as temperature and salinity, scientists can put sensors on sea creatures and download the data from back on land.

Next year, Hussey plans to use receivers on narwhals and several hundred tagged Greenland halibut to observe interactions between the two species.

"Basically your narwhal becomes your monitor of sustainable fisheries. He's swimming around, giving you detections on where your fish are," he said.

The tracking devices are not reserved for larger fish and mammals. Hussey says tags have become small enough to be implanted into a fish weighing only a few grams, and can be used on species including lobsters and jellyfish.

One advantage to using tracking for ocean research, Hussey says, is that the animals have access to places humans cannot reach by boat. Animals also spend more time on the job.

"These animals don't just go out like me and you for an eight-hour working day. These animals can monitor 24 hours a day, 365 days a year," he said.

The Ocean Tracking Network, based at Dalhousie University in Halifax, facilitates tracking in oceans around the world and includes more than 400 researchers from 20 countries.

The network centralizes ocean data so scientists can learn from each other's research, Hussey said, which allows them to tackle broader questions on how the environment shapes animal behaviour.

"These are obviously key questions that we want to ask when we're thinking about current climate change and predictions for the future as species start to redistribute themselves," he said.