Marine mammal specialists with Fisheries and Oceans Canada discovered a dead grey whale as they were patrolling an area with many reported sightings of the massive creatures.

Paul Cottrell, assistant marine mammals co-ordinator for DFO Pacific, says they found it in Boundary Bay Tuesday afternoon and immediately questioned whether it was the larger of two grey whales that’d been stranded in the area for hours there several weeks ago.

“The animal is flipped upside down so its ventral side is showing, but we’ll definitely looking at the markings on its side to see if it matches up,” he said, estimating it had been dead in the water for five days or less.

The veteran marine mammal rescuer and assessor spent hours with the carcass and says at first blush, there’s no obvious cause of death from what he could see.

“There were crab floats associated with the animal near the tail section, but we’re not sure if that was picked up after the animal died, so we’ll be looking at that and scars and a full necropsy tomorrow morning,“ he explained.

The Canadian Coast Guard hovercraft towed the animal toward its Sea Island base at just five knots per hour, taking several hours to make it there, only to arrive at low tide and discover the 14-metre mammal was too big to haul ashore till the water rose once again.

A mother and calf had been stranded by low tide in Boundary Bay May 10, struggling and then lying motionless for hours until the water levels rose enough for them to swim away. DFO experts had been monitoring the pair since, and had expected to spot them in Boundary Bay during Tuesday’s monitoring.

This whale is now added to the growing tally of dead grey whales along North America’s west coast that have experts concerned. Cottrell says more than 160 of the enormous mammals have been found dead in Canadian, American and Mexican waters.

“Every eight or 10 years we get a year like this where this is a high mortality among grey whales,” said Dr. Lance Barrett-Lennard, Director of the Marine Mammal Research Program at OceanWise. “The ultimate cause of most of those mortalities is the whales simply didn’t get enough food last summer.”

The bottom-feeding mammals experience the longest migration of any mammal, foraging for food in arctic waters all the way down to the Mexican coast. If they can’t get enough food on the way, particularly on the northern end in the food-rich Arctic, they may have enough blubber to make it back.

Barrett-Lennard says it’s possible that after decades of population growth and recovery, the whales may have reached the natural number sustainable by an ocean already under-producing small creatures the whales depend on due to warmer temperatures..

“It really worries us because those creatures are at the top and indicators of the health of the whole eco-system,” he said.

As they await the results of the necropsy that’ll determine the cause of this whale’s death, Cottrell hopes the public will keep an eye out for dead whales or those in distress and call their responders at 1-800-465-4336 if they see anything.

“The public is the eyes and the ears for the DFO marine mammal response network, we count on them to be able to help whales that are entangled and the faster we get to the dead ones, the better the chances we can determine why they died.”