Leopard seals are huge predators who mostly live in and around Antarctica. Though they will eat small fish and krill, they are the main predator for penguins. These seals can reach up to 3.5 m (11.7 ft) in length and tip the scales at up to 600 kilograms (1,320 lbs). They have massive sharp front teeth used for shredding meat and can open their mouths twice as far as a Grizzly bear. Yikes.