It's all about the blub­ber; get­ting caught in the middle of a shark fight; a pop­u­lar ship­wreck with a shady past.


Scuba Diving - - Contents - BY TRAVI S MAR­SHAL L

Among the an­i­mals that make their homes in the ex­treme po­lar re­gions of the planet, wal­ruses are some of the most iconic. Their mus­ta­chioed faces and long tusks make them im­me­di­ately iden­ti­fi­able, even though most peo­ple will never see one in the wild. Wal­ruses live in the Arc­tic Cir­cle along­side other denizens of the ice such as po­lar bears and nar­whals. Most peo­ple don’t re­al­ize there

are ac­tu­ally two sub­species of wal­ruses. At­lantic wal­ruses range from Canada to north­ern Europe, while Pacific wal­ruses range from Alaska to north­ern Rus­sia. Divers would be most likely to see them on an Arc­tic dive ex­pe­di­tion around Sval­bard, Nor­way.

Wal­ruses are part of the pin­niped clade, a sci­en­tific group­ing that also in­cludes seals and sea li­ons. How­ever, wal­ruses come from their own dis­tinct fam­ily, Odobenidae, of which they are the only re­main­ing liv­ing species. Wal­ruses can grow to an im­mense size — up­wards of 10 feet long and weigh­ing 2 tons — but they aren’t the big­gest pin­nipeds on the planet. That dis­tinc­tion goes to their cousins the ele­phant seals.

Like ele­phant seals, wal­ruses are highly so­cial an­i­mals, of­ten loung­ing on ice sheets in groups that can num­ber into the hun­dreds. Also like ele­phant seals, male wal­ruses get ag­gres­sive around mat­ing time, us­ing their large bod­ies and tusks to claim ter­ri­tory and harems of fe­male wal­ruses. The fe­males give birth after about 15 months, and they are known for dot­ing on their chil­dren, cud­dling them like hu­man moth­ers and car­ing for them un­til they’re about five years old.

A walrus’s most no­tice­able fea­ture is its tusks, and that was the ba­sis for the sci­en­tific name Odobe­nus ros­marus. The name is Latin for “tooth-walk­ing sea­horse,” and it comes from the walrus’s habit of us­ing its tusks like a climber’s ice ax to haul it­self onto ice sheets or cling to the edge while it floats in the wa­ter.

On land, wal­ruses are big, blub­bery crea­tures, but they’re still fast. Un­like seals, which drag their bod­ies with their flip­pers, wal­ruses can run on all fours. Of course, un­der­wa­ter is their true el­e­ment. Wal­ruses spend about two-thirds of their lives in the wa­ter, where they are as grace­ful as bal­leri­nas.

When it comes time to eat — which hap­pens of­ten for crea­tures this size — wal­ruses go mostly for in­ver­te­brates such as sea cu­cum­bers and clams. They find them on the seafloor by us­ing their whiskers, which are as sen­si­tive as hu­man fin­gers. Wal­ruses even have a spe­cial method for eat­ing shell­fish such as clams and mus­sels: They hold the shell in their mouth with their lips sealed around it, then cre­ate such strong suc­tion with their tongue that the meat pops out of the shell.

Wal­ruses are so­cial mam­mals and care for their off­spring for up to five years.

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