There are three subspecies of walrus: the Atlantic walrus which lives in the Atlantic Ocean with a population of around 20,000, the Pacific walrus found in the Pacific Ocean with about 200,000 individuals, and the Laptev walrus living in Siberia's Laptev Sea numbering 10,000. Walruses mainly eat mollusks from the seafloor but also consume worms, shrimp, crabs and occasionally seals or young walruses. They can weigh up to 1,996 kg and grow to 4.5 meters in length, living for around 40 years. While clumsy on ice, walruses are agile swimmers.