The basking shark is the second largest fish in the world, and like the largest fish (the whale shark) and the largest animal (the great whales), basking sharks are filter feeders that eat tiny, planktonic prey. Reaching lengths of 40 feet (12 m) and resembling predatory sharks in appearance, the basking shark can give an intimidating impression, but they are quite harmless. They spend most of their time near the surface, swimming with their extraordinarily large mouths open, filtering out their preferred prey, but they may also make deeper, feeding dives.