More gear, underwater gliders to be used in ongoing effort to save right whales

Canada will triple underwater glider missions in the Gulf of St. Lawrence in 2018 in an effort to detect endangered North Atlantic right whales.

Two new unmanned gliders — each costing $300,000 — have been purchased to carry out the expanded surveillance program. The self-powered two-metre gliders are used to study whale movements by listening to and recording their sounds.

The glider program is being run out of Dalhousie University in Halifax, but is bankrolled by the Department of Fisheries and Oceans, which paid for new gliders, upgraded equipment and support technicians.

"It's all because of the whales. It's driven by the whales," said Richard Davis who runs Dalhousie's glider operation. "It's considerably more than my budget in any one year."

Preventing a catastrophic repeat

A dozen North Atlantic right whales died in the southern Gulf of St. Lawrence last year after being struck by ships or entangled in snow crab fishing gear.

"At this rate we are looking at the extinction of the species in 20 years. We have to ask ourselves, 'Is this an animal we want to see disappear off the face of the planet?' My answer is no. We are putting a lot of energy into finding out what's going on," said Davis.

The federal government has announced a wide range of measures to protect the whales this year, including an earlier start and end to the snow crab season and a lowering of shipping speed limits. It also promised increased aerial and at-sea surveillance to detect whales. That's where the glider effort comes in.

In 2018, three gliders will patrol the Gulf continuously from June to the end of November. That is up from the single glider used in 2017.

This year, one glider will be stationed along the St. Lawrence Seaway shipping lane to warn mariners. Another will patrol in the areas where whales were tracked in 2017. It has not been decided where in the Gulf the third glider will be deployed.

"The gliders have the advantage they are out there 24/7. They are are not affected by the weather. It doesn't matter if the seas are rough. It doesn't matter if it's foggy. They are out there listening," said Davis.

Smart enough to tell whales apart 

The Slocum gliders used by Dalhousie carry hydrophone technology developed at the Woods Hole Oceanographic Institution in Massachusetts that is capable of distinguishing right whales from other whales in near real-time.

The underwater drones surface every two hours and transmit data to satellite, including a small burst of the whale call.
The gliders can also measure the density of the tiny zooplankton that right whales feed on, which is a potential predictor of their likely whereabouts.

The drawback? Gliders are slow

As useful as the data is, Davis said gliders have a drawback.

"The downside to them is they are very slow. If you've got whales over here, it takes a while to transit the glider from where it is to an area," he said.

That's why gliders need to work with aircraft and surface vessels.

"By using all three, we get a much better picture of where the whales are," said Davis.

Are acoustic buoys part of the solution?

Davis is an advocate of fixed acoustic monitoring buoys — along, say, a shipping lane — and using gliders to search for where the right whales might show up.

Last year, about 100 appeared in the Gulf, leaving the whereabouts of the remaining population of the 300 to 400 right whales largely unknown.

This year, Dalhousie gliders will also increase patrols in the Roseway Basin off southern Nova Scotia in case they return to the area they once regularly frequented in summer.

Two other agencies based at Dalhousie are also contributing time, money and effort to the right whale surveillance efforts. They are the Ocean Tracking Network and Marine Environmental Observation Prediction and Response Network.