For the past few years light planes, boats, and snowmobiles have been taking hunters to the polar ice cap in such numbers that the polar bear may be threatened with extinction. The animal is being killed as never before. Even with strict regulation, the annual kill in Alaska (about four hundred) has more than tripled in twenty years and brings to the Alaskan economy over $600,000 a year. Of the five interpolar countries— Canada, United States, Norway, Denmark (Greenland), U.S.S.R.—only Russia fully protects the polar bear. In Norway a hunter can trap bears by setting a baited gun. This often means cubs are left to die after the sow has taken the bait and been shot. With a snowmobile, a whole string of such traps can easily be maintained. The snow-mobile has also become standard equipment for Eskimos and Indians in Canada, where by far the greatest number of bears are killed—six hundred a year.

In 1968 an international “Polar Bear Group” was formed under the auspices of the International Union for the Conservation of Nature and Natural Resources (I.U.C.N.) to study the bear’s migration patterns, population, and ability to withstand arctic conditions. But unfortunately polar bear tracking and counting devices are still in their infancy. The current technique of state and federal teams in Alaska begins with finding the bear, using a ski-equipped light plane and a helicopter. Twenty minutes after the animal has been tranquilized with a dart gun fired from the helicopter, he is turned loose with a tag in each ear, an experimental collar about his neck, and big purple numbers on his flank to warn off hunters. He will also have been weighed by being dangled in a net from the helicopter, and he will have had one small tooth removed. (Like the rings of a tree, a tooth cross section will show his age.) Preliminary evidence from four hundred polar bears tagged during the past three springs indicates that the bear is not circumpolar, as was thought, and that there may be separate regional races. If true, this would mean each interpolar country could manage its own bear population.

The polar bear is large (up to a length of nine feet and a weight of one thousand pounds) and carnivorous (primarily seals), and he wanders over the ice drift some twenty to forty miles a day in search of food. In fact, the bears never go to land except to have their young, and fewer and fewer of them are doing even that. They are tough animals to study. The best hope for successful tracking of the polar bear lies in electronic transmission—a radio transmitter on the bear’s collar that will send a beep to an earth-circling Nimbus satellite. A transmitter and battery able to operate at 50 degrees below zero and to withstand frequent plunges into icy waters is being developed, and by 1971 polar bears will doubtless be