Covering its nose. Dr. Ian Stirling and several assistants used telescopes to watch undisturbed polar bears hunting seals in the Canadian High Arctic—24 hours a day when conditions permitted, in both spring and summer conditions, for several weeks each year, over several years. They documented the details of many hundreds of hunts. No bear was ever seen putting a paw over its nose while stalking a seal. Nor, to our knowledge, have other polar bear biologists ever observed this behavior. Simply from a mechanical point of view, Stirling expresses puzzlement about just how a bear might walk, crawl, or stalk on three legs while holding its paw over its nose for an extended period since most stalks on the sea ice cover 50 to as much as 200 meters.
Left pawed. There is no evidence to support the notion that all great white bears are left-pawed. Scientists observing the animals haven't noticed a preference. In fact, polar bears seem to use their right and left paws equally.
Use of tools. Polar bears do not appear to use tools, including blocks of ice, to kill their prey. Scientist Ian Stirling believes that this idea may have come about because, after failing to catch a seal, a frustrated and angry polar bear may kick the snow, slap the ground—or hurl chunks of ice.
Hollow hair conducts UV light. A polar bear's hollow hairs do not conduct ultraviolet light to its black skin. This theory was tested—and disproved—by physicist Daniel Koon.
Mutalism with arctic fox. Polar bears do not share food with the arctic fox in exchange for the fox's warning system. Scientists discredit the notion. Arctic foxes do travel behind polar bears and scavenge on scraps, a relationship defined as commensal. In fact, arctic foxes often annoy polar bears by nipping at their heels in an attempt to drive a bear off its prey. Polar bears sometimes lunge at or slap a fox. During the spring season when both polar bears and arctic foxes hunt ringed seal pups, they can be considered competitors.
The arctic fox is also a significant carrier of rabies and its transmission to and affect upon polar bears is poorly understood. There is one documented case of active rabies in a polar bear from the Northwest Territories, Canada that led to the bear being euthanized. Increasing transfer of existing and new diseases is a significant concern as the Arctic continues to warm.
Orca whale predation. Scientist Ian Stirling concedes that an orca might have an opportunity to attack a bear stranded on a remnant of ice or while swimming in open water, but it's extremely unlikely. To date, there are no reported or documented cases of such predation or attempts. However, as Arctic sea ice continues to recede, reports of orcas using waters in the Far North are growing, suggesting a range expansion is in progress for some regions like Hudson Bay.
Bi-polar bears? Polar bears live only in Arctic areas in the northern hemisphere—not in Antarctica, which is in the southern hemisphere. People often see illustrations of penguins and polar bears together, but this could never happen in the wild. In fact, the word Arctic comes from the Greek word for bear, and Antarctic comes from the Greek meaning the "opposite of the Arctic" or "opposite of the (great) bear."