Like all toothed whales, they are carnivores. Killer whales are apex predators and they hunt in family groups called 'pods'. Members of the pod work together to surround their prey. Killer whales eat many different kinds of prey, such as small sharks, seals, sea lions, dolphins, whales, penguins, seagulls, squid, octopuses, stingrays, crabs and sea turtles. In 1997, the first known killer whale attack on great white sharks was documented off the coast of San Francisco. There are several different types of "Orca", each of which has different living and prey habits. They do not interbreed and seems to be subspecies or even separate species. Their behaviour and hunting techniques also differ.