The grey whale that washed up on the beach at East Sooke Park on Easter weekend is among five that have perished in area waters over the last two weeks, and all seem to have died from starvation.

This spate of grey whale deaths is not unusual, say marine biologists. In 1999, more than 100 grey whales died on the West Coast and in 2000, 12 died along the B.C. coast.

article continues below

"This is nature -- we get these cycles," said Paul Cottrell, acting marine mammal co-ordinator for Fisheries and Oceans Canada.

"We have to keep our eye on it. If this year is like 1999, we're going to have lots of grey whales die."

The reason emaciated grey whales turn up here and die has to do with the remarkable three-month migrations the mammals make each year, starting in October, between their feeding grounds in the Bering Sea and mating areas in southern California and Mexico.

It's one of the longest migrations by mammals on the planet. The whales don't head north again until sometime between February and May, with mothers and calves sticking around the longest.

They do almost all their feeding in the far north, said Lance Barrett-Lennard, head of the cetacean research program at the Vancouver Aquarium.

"They're thought not to eat at all on the southbound migration and they may snack a little bit on the northbound migration," said Barrett-Lennard.

"It's even worse for females -- they have to swim all the way from the Arctic to warmer areas, produce a calf and swim back with the calf. They're lactating all the way and the calf is growing like fury.

"The calf is twice as big when it gets to the Arctic. The poor female is dumping out all this fat-rich milk into the calf and trying to make this incredible migration."

The deaths of grey whales stem from poor food supplies in the Bering Sea last year, said Barrett-Lennard. "If they have a poor feeding year, they usually have enough fuel to get all the way south. Where they tend to run out is on the way north again -- they're running on fumes."

Almost all of the 20,000 grey whales in the eastern Pacific make the round trip each year.

Between 100 and 200 choose to stop in B.C. waters and do their feeding there, said Howard Garrett of Orca Network.

"They know where to go and they find the food and do very well," said Garrett yesterday.

The grey whales who don't know the area come in because they're desperate for food, Garrett said. Grey whales feed in shallow waters by scooping up mud and using their baleens as a filter.

"They turn into the Strait of Juan de Fuca and meander everywhere," Garrett said. "They show up in the most remote, dead-end locations in the labyrinth of inlets, way down in Puget Sound and all over the place. Often they die."

On Easter weekend, a grey whale washed ashore at East Sooke Park. Another landed in Oakland Bay in the southern reaches of Puget Sound.

Last Saturday, a grey whale beached at Samish Bay near Anacortes. The next day, another dead whale turned up north of Whidbey Island in Deception Pass.

Then on Wednesday, a grey whale died near west Seattle.

Several of the dead whales have dried blubber, which indicates they've been drawing on their own fat supplies for energy, said Garrett.

One whale had a large quantity of sawdust in its stomach. "It had been attempting to find food in a mud flat that was near an old sawmill," Garrett said.

The grey whales get thinner and lose insulation, so they have to use more energy just to stay warm, said Barrett-Lennard. "It's a double whammy."

smcculloch@tc.canwest.com