Low-hanging clouds laden with snow, raced above the forever-frozen landscape as an aged DC3 lumbered along an ice-clad runway here recently and strained to become airborne.

The cargo: four polar bears, about to be "saved" by the International Fund for Animal Welfare, which also has conducted highly publicized annual campaign to stop the slaughter of baby seals.

Although the dramatic airlift has garnered worldwide attention for the Canadian-basde organization - a considerable bonus at fund-raising time - there is some question about whether it has done much for the polar bears.

These bears - two adults and two cubs - were being flown from his outpost on Hudson Bay, 1,200 miles north of Minneapolis, that serves as a grain shipping port and a regional government center. The polar bears congregate here once a year, ocassionally causing property damage and scaring the 1,600 human residents.

The animals were bound for a desolate site 300 miles to the south, where they would be released away from harm from humans.

But more than likely, at least one of the refugee bears will return to Churchill despite the rescue. In the seven years since the airlift began, about half of the 70 bears moved reappeared in Churchill a few weeks later. One made the trip in a record 11 days.

Manitoba conservation officials view the airlift with some skepticism. However, because the program is privately financed by the fund - which pays $500 for each bear airlifted - they cooperate.

The only alternative for now is to shoot the bears that become nuisances, a plan that some government conservationists think might be a much better idea anyway.

But, said an official of the Manitoba Department of Renewable Resources, "At this time, the politicians aren't prepared to consider any harvest."

So the government goes along with bear-lift, and its surrounding publicity, even so far as to interrupt research efforts to allow visiting journalists to pose with a tranquilized bear in their laps.

The root of the problem that led to this airlift is that once each year, usually in the late October and early November, many of Manitoba's 1,100 polar bears gather in and around Churchill to wait for Hudson Bay to freeze. Once that occurs, the bears move onto the ice, where they begin a winter and spring of hunting seals, gradually heading south in the process.

By late summer, only small ice floes remain at the southern end of the bay, and the bears return to land. They immediately begin their migration northward, across the empty trundra, back to Churchill to wait for winter.

So strong is this migratoy instinct that - short of evacuating Churchill's residents for a few weeks annually - there seem to be few ways to lessen the potential man-bear conflict.

But this supposed to be the last year for the benefit. Next year, the plan is to impound the bears arriving in Churchill in a new, government built preserve where an attempt will be made to hold them until the bay freezes. Officials hope this will be a much more efficient way to handle the situation.

The four bears on this airlift had been snared in or near the town dump, and were considered "problem" bears. Last year, the worst year for bears that conservation officials can recall, 19 were destroyed.

These numbers gain in significance in light of the fact that the polar bear is considered an endangered species in every nation to which it is native except Canada.

In fact, some conservations officials in Manitoba think that the Canadian polar bear population is "too healthy," and should be thinned out to allow more bears to mature.

"A thousand-pound bear takes up the territory that could support four smaller bears," said Kim Mann. of the Department of Renewable Resources. "Therefore, if you harvest a thousand-pound animal, there is more range for more bears."

That kind of thinking did not sit well with the International Fund for Animal Welfare, which for 12 years has flown journalists onto the ice near Newfoundland to observe the annual, bloody baby seal hunt. This spring, the fund arranged for Brigitte Bardot, who arrived in a fur coat, to make a brief guest appearance at the site.

Although there are almost as many stories about polar bear encounters in Churchill as there are residents, there have been only four recorded attacks on humans - one fatal - with the last occuring in 1970.

It is easy to forget the potential dangers. Polar bears, with their big feet, plump bodies, fluffy white fur and loping gait, seem more like pets than killers. In fact, though, they are hunters that can outrun a man and kill a 500-pound seal with ease.

During the polar bear migration season, conservation officers here work round-the-clock. Residents are instructed to call a special phone number if a bear is spotted.

This year, 26 bears were caught in and around Churchill and 13 airlifted.

Steve Kearney and Roy Bukowski of the Department of renewable resources have been studying the bears for 1 1/2 years for the Manitoba government.They also are conducting an educational program for the public to lessen the conflict between man and animal.

"We don't want to give the people a wolf outlook on bears," said Kearney. "We want them to like the bears, but also to know they can be dangerous."

"We want everyone who comes to Churchill to see a polar bear because there just aren't too many places where you can see one. They are beautiful animals."