Tuesday, October 11, 2011

{Press} Right whales still creatures of mystery

The Chronicle Herald.ca | Davene Jeffrey | October 7, 2011

"Researchers have been studying North American right whales for the past 30 years but much about the mammoth mammals remains a mystery.

One-quarter of the world’s population of 475 North American right whales leave the warm waters off Florida every spring and disappear somewhere into the North Atlantic, says Scott Kraus, the New England Aquarium’s vice-president of research.

"These animals are just missing."

Another quarter veer slightly east on their seasonal swim up the Eastern Seaboard and spend their summers in an area of the ocean called the Roseway Basin, about 65 kilometres south of the southern tip of Nova Scotia.

And about half of them regularly summer in the Bay of Fundy.

Last week researchers counted about 60 in one day.

Last year was different. Most of them didn’t show up. Researchers only counted about 50 whales in the bay that entire season.

"It’s looking like last year was just an anomaly," said longtime researcher Moira Brown, who is also based at the aquarium.

Other strange happenings in the whale world occurred in the bay in 2010 as well.

"For the first time in our 32-year study, we had sperm whales, quite a few of them, seven or eight of them. In the last 30 years, we’ve seen two sperm whales in the Bay of Fundy," Kraus said.

Why sperm whales suddenly showed up is a head-scratcher for the marine biologists, although Kraus suggests they might have been chasing squid.

Some people speculate the presence of the sperm whales could explain why the right whales went elsewhere, Kraus said.

Sperm whales make very loud echolocation clicks and "maybe that is just annoying to everybody else," he said. "We really have no idea."

While the return of the right whales to the Bay of Fundy this year is good news for researchers, the whales do appear to be shifting their travel trends.

In the ’90s, the whales typically summered in the bay between July and mid-October, but "over the last 10 or 15 years we’ve see this shift," Kraus said. "We hardly ever see any right whales in July any more and they’ve moved much later in the season. Even this year, in August we didn’t have a whole lot of whales but then they really piled in in September."

The scientists have been looking at links between climate change and whale movement but with so many unknowns, Kraus said drawing any sort of conclusions is very tricky.

What they do know for sure is that over the past decade, the right whale has experienced a slight population growth of about one per cent a year.

Two Canadian whale preservation measures have had great success, Kraus said.

Shipping lanes changes in the Bay of Fundy and near Roseway Basin have decreased the number of whale-ship collisions in Canadian waters by between 80 and 90 per cent, Kraus said.

But North Atlantic whales are still struggling for survival with the commercial fishery, said Brown

"About 82 per cent of whales have scars on their body from entanglements with fishing gear," she said.

In Canada, there has been very little movement on part of the federal Department of Fisheries and Oceans to regulate the fishery, Kraus said.

However, in the United States "there’s a lot of effort but we’re not seeing much success either," he said.

( djeffrey@herald.ca)"

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