Warmer climate, more orcas threaten beluga: study

WINNIPEG — A study suggests a warming climate and more killer whales could bring harm to beluga whales in the southwestern portion of Hudson Bay.

The study included researchers at Oceans North Canada, the federal government and the University of Manitoba.

It looked at an attack by killer whales on belugas near the mouth of the Seal River in northern Manitoba in August 2012.

Research showed that after the attack, the belugas scattered northward along the Hudson Bay coastline, away from a traditional calving area near the Seal River.

The study suggested such scattering could affect the survival rate of young belugas.

It also noted that as the climate warms and the water in western Hudson Bay sees longer ice-free periods, the presence of killer whales might grow.

“Here, short-term changes in distribution were recorded in relation to a predation event,” said the study published in the Canadian Field-Naturalist.

“This change, if occurring multiple times during the longer ice-free season, could have significant biological consequences related to energy expenditure and success in calfrearing.”

Kristin Westdal, one of the study’s authors, said such attacks don’t have much of an impact yet on the estimated 60,000-member beluga population in western Hudson Bay.

But that could change if the ice-free season continues to expand and the killer-whale population grows, she said.

“Any predation on those animals wouldn’t be significant at this point, but going forward in the future … it could be a fairly significant event,” said Westdal, a marine biologist for The Pew Charitable Trusts’ Oceans North Canada project.

The study’s findings point to the need for environmental protection in more areas of western Hudson Bay, both in the water and on land, Westdal added.

“We really didn’t understand [until now] how much of the coastline they were using.”

Last year, the former NDP government in Manitoba called on the federal government to extend a ban on industrial waste discharges from ships, which covers the Arctic, farther south into the sub-Arctic portion of Hudson Bay.

It also announced plans to protect beluga whales in the area by reducing noise and other impacts from shipping traffic out of the Port of Churchill.

A spokesperson for the Progressive Conservative government didn’t respond to questions about whether it would follow through with those plans.