The walrus is known for using its tusks to enlarge or maintain breathing holes in sea ice.
Walrus tusks are elongated canine teeth present in both males and females. They serve several purposes, including display, fighting, hauling out onto ice, and manipulating the ice around breathing openings. A walrus can use its tusks to pull its heavy body from the water onto a floe, although it does not routinely drill through very thick ice from below.
Walruses also have sensitive whiskers called vibrissae. These help them locate clams and other bottom-dwelling prey in dark or murky water. Their diet is dominated by benthic invertebrates, especially bivalve mollusks.
The species lives around the Arctic Ocean and adjoining sub-Arctic seas. Two commonly recognized subspecies are the Atlantic walrus and Pacific walrus. Their tusks are not horns: they are teeth, a distinction that separates them from the horn structures of many hoofed mammals.