It was once thought that this pinniped raked the ocean floor with its tusks to look for food
[DOC] [TLE] Walruses, Walrus Pictures, Walrus Facts - National Geographic [PAR] Male walruses, or bulls, also employ their tusks aggressively to maintain territory 
... particularly shellfish, are found near the dark ocean floor, walruses use their... [DOC] [TLE] The Marine Mammal Center : Pinnipeds [PAR] At sea, true seals move their rear flippers back and forth like a fish's tail to propel 
... females have tusks and vacuum-like mouths for sucking up shellfish from the 
ocean floor.