Ferguson's team last year was notified of spottings of the black and white orca, (Orcinus orca, popularly called killer whales) by scientists, tour operators and Inuit fishermen who criss-cross Hudson Bay, a North Canadian inland sea bigger than France.

In the 1980s, experts counted between five and 10 summer spottings of orca each year in the same area. That number jumped to about 30 last year, the Canadian researchers said.

During the same period, the ice cover in the Arctic has sharply declined. By 2040 the ice could be completely gone during the summer, according to a study by Canadian and US researchers recently published in the journal Geophysical Research Letters.

Ferguson's team was unable to identify where the orca seen in Hudson Bay were coming from, but they said it was probably from the northern Atlantic Ocean, near Iceland or Nova Scotia.

The researchers also were unsure what was on the menu for the giant creatures, which are not true whales but instead the largest members of the dolphin family.

"We don't know for sure what the killer whales are eating. Some killer whales eat fish but we don't think there is that much good fish food for them in the Arctic. So we are working on the assumption that they are probably eating belugas, narwhals, bowhead and maybe seals as well," Ferguson said.

Their migration is worrying fishermen of the Inuit, the indigenous Eskimo people of the region, he said in discussions of the research led in cooperation with the University of Manitoba.

"It's a real concern for the hunters. They think it is competition for their food (because) the whales that they would be shooting and eating would be attacked by the killer whales," he said.

Greenland Cuts Polar Bear Hunting Quota
Copenhagen (AFP) Jan 18 - Greenland on Thursday said it would cut its annual quota for its polar bear hunt as the animal was threatened by climate change. Warmer temperatures have caused the Arctic ice cap to melt, shrinking the bears' hunting grounds and making it increasingly difficult for them to find food.

Hunters, who can get up to 2,685 euros (3,500 dollars) for a bear pelt, had been killing around 250 bears a year before the first quota of 150 kills was introduced for 2006.

The quota for 2007 has now been reduced to 139 in the semi-autonomous Danish territory.

"We have decided on this reduction in the 2007 quota to be more in line with a level suggested by biologists, who wanted an even lower number," a ministry of fisheries and hunting official, Ole Heinrich, told AFP.

The decision was taken after consultation with local authorities and the Greenland Hunters and Fishers Association (KNAPK), said Heinrich, who spoke to AFP by telephone from Greenland's capital Nuuk.

KNAPK president John Billmann criticised the authorities for not having stuck to plans to allow the killing of 203 bears.

Only hunters who are granted special permits are allowed to hunt polar bears. The hunting of bear cubs and pregnant bears is banned.

There is a complete ban on the hunting of polar bears between July 1 and September 30.

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