![]() A polar bear can occasionally catch a fleeing walrus on land, but even the biggest polar bear cannot subdue a healthy adult walrus. A marauding polar bear will only rouse the whole group into a panicked charge back into the sea, where they are safe. Walruses, by contrast, are gregarious animals that usually come ashore in large, tightly packed groups. Just imagine how devastatingly effective polar bears would be if they hunted in packs! But they never do - they are solitary hunters. What’s amazing is that, unlike lions and wolves, bears do not hunt cooperatively. This might not be so surprising, considering that lions and wolves hunt prey much larger than themselves. Walruses are the largest pinnipeds (seals) in the Arctic but they are not top predators they eat primarily mollusks from the seabed.ĭespite the huge disparity in size, polar bears do hunt walruses. An adult male walrus (Odobenus rosmarus) can weigh more than 2,000 kg (4,400 lb), about three times as much as a polar bear. Which is bigger, a polar bear or a walrus?Ī mature male polar bear (Ursus maritimus) can weigh more than 700 kg (1,500 lb), making it one of the largest land carnivores on Earth. A few of our expedition team members weighed on the subject of these two fearsome creatures to give their views on who really rules whom. Within the frozen realm of this renowned monarch, there lives another powerful Arctic denizen who does not readily submit to ursine rule - the mighty walrus. “It is important to understand how polar bear hunting success will be affected by these changing conditions.The polar bear is often called the king of the Arctic. “Wind speeds in the Arctic are projected to increase, potentially making olfaction more difficult,” explained Togunov. Like most studies done in the Arctic these days, the findings also gave scientists pause about the implications of climate change on these polar bears. “Crosswind search was most frequent when winds were slow, when it is easier to localize the source of a certain smell, and at night when bears are relatively active and when vision is less effective, so bears rely more heavily on their sense of smell,” explains University of Alberta professor Andrew Derocher. ![]() The researchers found that the best conditions for this type of hunting usually occur at night in the Arctic winter. But they were left wondering what a polar bear might do before it even catches on to a smell.Īs Togunov explains, “Travelling crosswind gives the bears a steady supply of new air streams and maximizes the area they can sense through smell.” This behavior was suspected in many animals, but this is the first time scientists have been able to quantify it in mammals. ![]() Before beginning the study, the researchers had hypothesized that when a bear smells prey, it moves up-wind to find it. “Predators search for prey using odors in the air, and their success depends on how they move relative to the wind,” says Ron Togunov, University of Alberta alumnus and lead author on the study. They then combined the movements of these polar bears with wind patterns in order to see how the two matched up. The researchers attained satellite telemetry data collected from more than 120 adult polar bears in Canada’s Hudson Bay over an 11-year period. Although that “discovery” may seem rather obvious, it goes a little deeper than that. ![]()
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