This month, we want to talk about a very large pinniped, the walrus (Odobenus rosmarus)! Learn about our tusk fighting, mollusk eating, flipper footed marine mammal of the month. We hope to highlight some facts and their climate-changing plight.
Where in the world do they live?
There are two subspecies of walrus. The first one occupies the north Atlantic waters, from northeastern Canada to Greenland. The second subspecies inhabits the Pacific, off the coast of Russia and Alaska. Their range extends as far south as the Bering and Chukchi sea. Walruses, therefore, live in a cold Arctic environment. As a result, their bodies are well adapted to their freezing environment. Their blubber can make up about one-third of their body mass!
What’s on the Menu?
Walruses prefer mollusks, such as clams. Yet, they are not picky eaters! Walruses also eat many kinds of benthic or sea-floor inhabiting creatures, including worms, gastropods, cephalopods, crustaceans, and sometimes even polar cod. Walruses eat about twice a day. Adults, on average, eat as many as 3,000-6,000 clams in a single feeding session! You may be wondering how they find these benthic creatures in such deep, murky waters.
They, like sea lions and even manatees, have vibrissae (similar to whiskers). They move their snouts along the sea sediment, and their vibrissae will pick up on the movement of their prey. On occasion, if food is scarce, they may feed on young seal carcasses. A rarity, some walruses eat ringed and bearded seals regularly.
Walruses are, of course, known for their gigantic tusks. Yet, contrary to what one might think, they do not use their tusk for hunting…
Tusks, a tool of all trades
Walruses are known for their iconic tusks. Males use them against others to maintain or overtake another male’s harems or a herd of females during mating season. But that’s not their only use! Both males and females have tusks that can extend about three feet long. Walruses use their large canine teeth to “tooth-walk” as they haul their bodies out of the water. When they need it, they can even use them to break holes in the ice when underwater!
Effects of Climate Change
In the 18th and 19th centuries, walruses were hunted to near extinction. Their meat, oil, skin, and tusks were hot commodities. Walruses were hunted entirely out around the Sable Island in the Gulf of St. Laurence, off Nova Scotia’s coast. Now only indigenous people hunt them.
Presently, climate change is driving walruses off the edge, literally. Many of you might have watched the Netflix “docuseries” Our Planet. In one of the episodes, Frozen Worlds, there is a segment that highlights walruses. Due to climate change, sea ice is forming later each season and receding earlier throughout the Arctic. These lead to very few places where walruses can haul out; they have to swim farther out for food and have fewer refuges on the water. As pictured above, walrus have to assemble in massive haulouts that can be very dangerous—Walruses stampede when spooked. Larger walruses trample calves and other small walruses, which can cause injury or even death. A high risk of human-wildlife interaction happens when more walruses haul out on land.
As a global community, we need to mitigate the acceleration of what was supposed to be a natural cycle. So make sure to share this article with somebody who needs to know about walruses and climate change!