Humpback whales move north. Warm oceans may be the cause

Humpback whales are steadily moving north, and warmer seas and melting ice may be the reason.

The whales, which move between the Antarctic and the southern tips of three continents, will be the focus of a six-year, $5 million study into their migration routes by eight research institutions across South America, South Africa and Australia.

“Their migratory behavior is changing, they are going further and further north,” said Alakendra Roychoudhury, an environmental geochemist at Stellenbosch University in South Africa. “If the physical and chemical conditions of the oceans change, what will happen to the whales?”

The study will involve multiple cruises to the whales’ feeding grounds in the Southern Ocean off Antarctica and the coastlines of the three continents where they breed. It will combine historical migration and whale-sighting data with the new research to determine the impact of both warmer oceans and melting ice, which may change the chemical nature of the ocean, Roychoudhury said by phone Tuesday.

In South Africa, the humpbacks, which eat phytoplankton and krill, have been seen in large numbers, known as super groups, further and further up the west coast toward Namibia.

“This has never happened before,” Roychoudhury said. “Off the Australian coast they are seeing similar kinds of things.”

Roychoudhury conceptualised the study together with Brendan Mackey, director of the Griffith Climate Change Response Program at Griffith University in Australia. Researchers from Chile, Brazil, Ecuador and Panama will also participate. The project will have 16 full-time researchers.