玛丽艾伦
The killer whale is the largest species of dolphin in the world and, like all dolphins, is a cetacean. It is also called an orca or killer whale. Whalers gave the killer whale the name “killer whale” because it looks brutal when the killer whale is chasing its prey.
Killer whales are up to ten meters long and often weigh several tons. A ton is 1000 kilograms, as much as a small car weighs. They can live up to 90 years. The dorsal fin of the killer whales can be almost two meters long, looks a bit like a sword, and also gives them their name. Because of their black and white coloration, killer whales are particularly easy to spot. They have a black back, a white belly, and a white spot behind each eye.
Killer whales are distributed around the world, but most live in cooler waters in the North Pacific, and North Atlantic, and polar seas in the Arctic and Antarctic. In Europe, killer whales are most common off the coast of Norway, with a few of these whales also found in the Baltic Sea and southern North Sea.
How do killer whales live?
Killer whales often travel in groups, traveling at speeds of 10 to 20 kilometers per hour. That’s about as fast as a slow bicycle. They spend most of their time near the shores.
The killer whale spends more than half of the day looking for food. As a killer whale, it feeds primarily on fish, marine mammals such as seals, or seabirds such as penguins. In groups, the killer whale also hunts other whales, which are mostly dolphins, i.e. small whales. Killer whales rarely attack humans.
Not much is known about reproduction. Killer whale cows become sexually mature at around six to ten years of age. Pregnancy lasts one to one and a half years. At birth, a killer whale calf is two meters long and weighs 200 kilograms. It suckles milk from its mother for a year or two. However, it is already eating solid food during this time.
From one birth to the next it can take two to fourteen years. A killer whale cow can give birth to five to six cubs in its lifetime. However, almost half of them die before they have young themselves.