Approximately 7-9 meters in total body length and weighing between 3 and 10 tons, orcas (killer whales) are carnivorous mammals that live in oceans around the world. They are colored black and white. Their unique dorsal fins can grow to a maximum length of 2 meters and they are the fastest marine mammal around. Orcas are very savage and are natural-born hunters. They prey on fish, squid, seabirds, penguins, and at times, South American sea lions, seals, dolphins, polar bears, whales, and sharks as well. Differentiating between the sounds they emit allows them to communicate with each other.