Orcas are big, powerful predators. Their backs are black, and their stomachs have white patterns. Males have a tall triangular dorsal fin and females have a shorter curved fin. A male can be 8 metres long and weigh about 5 tonnes. Sometimes known as killer whales, these marine mammals actually belong to the dolphin family. They live in all the oceans of the world, in social groups called pods. They will kill sharks and whales, but there is no record of them attacking humans.
New Zealand orcas
There are fewer than 200 orcas living in New Zealand waters, where they are protected. The pods are generally small – around two to four orcas. Researchers are still discovering facts about New Zealand’s orcas. For example, more have damaged dorsal fins than orcas in other regions, although the reason is not known.
Where do they live?
There are three main groups. Although they move about a lot, one group spends more time around the North Island, another off the South Island, and a third group swims off both islands. You can spot orcas off the coast of the Bay of Penty, East Cape and Hawke’s Bay in June, and from October to December. They can travel up to 170 kilometres a day. Scientists reported two males travelling 2,000 kilometres from Auckland to Kaikōura.
What do they eat?
Orcas will attack and eat fish, squid, and seals, and larger prey such as sharks, dolphins and whales. New Zealand orcas also like to eat stingrays, eagle rays and electric rays. This can be dangerous, as rays have poisonous spines.
Contact with humans
Orcas have no enemies apart from humans. They may not be killed or captured in New Zealand, but they can be harmed by boats, fishing nets and pollution. Sometimes when an orca feeds close to shore it becomes stranded on the beach. In the past stranded orcas were shot to put them out of their misery, but today people try to return them to the ocean.