Fam.: Delphinidae Killer whales are familiar to most people due to their unmistakable black-and-white colour pattern and their spectacular habit of preying on other marine mammals. However, they also take a variety of schooling fish, and large numbers of killer whales gather each autumn in the Norwegian Tysk Fjord to prey on spawning herring. Killer whales are the largest members of the family Delphinidae, with adult males exceeding 9 m in length and weighing almost 10 tons. Females are considerably smaller.

Orcas are a truly cosmopolitan species, distributed throughout the World Ocean and all climatic zones. Killer whales are common around the northern part of the British Isles, along the Norwegian coast and throughout the eastern North Atlantic. They occasionally enter the North Sea and Skagerrak.

Illustrations: M. Camm