Orcas: Facts about killer whales

Orcas were originally called "whale killers" because ancient sailors saw them hunting in groups to take down large whales. Over time, that name morphed into "killer whales."

Killer whales are apex predators, which means they're at the top of the food chain and no animals (other than humans) hunt them. Killer whales eat many different types of prey, including fish, seals, seabirds and squid. They also take down whales larger than themselves, such as minke whales, and they are the only animal known to hunt great white sharks. They've even been spotted teaming up to kill blue whales, the biggest creatures on Earth.

Scientists don't know whether orcas kill for fun. The marine mammals do some things, like killing and tossing dead porpoises in the air, that raise that question. But while playing catch with a dead porpoise could be a form of play, it could also be hunting practice.

Orcas are the largest members of the dolphin family. Males are bigger than females, but they both vary in size and weight. The largest orca ever recorded was a staggering 32 feet (9.8 meters) long and weighed 22,000 lbs. (10,000 kilograms). That's longer and heavier than most RVs.

An orca's body has a special pointy shape that helps it move quickly and efficiently through the water. This shape, along with the orca's large size and strength, makes it one of the fastest marine mammals. It can reach speeds of 35 mph (56 km/h) — faster than Usain Bolt's Olympic sprinting record. Orcas also have massive teeth, which can grow up to 4 inches (10 centimeters) long.

There is no record of an orca ever killing a human in the wild. One of the few documented near-attacks — an orca charging at a surfer in Norway before pulling away — most likely happened because the animal mistook the surfer for a seal.

Although wild killer whales do not intentionally harm people, they have attacked boats. In the summer of 2020, orcas rammed into and damaged sailing boats near Spain and Portugal. Three young male orcas were behind most of the attacks, and biologists think the young males were playing with the boats.

Orcas in captivity sometimes attack humans. Captive killer whales have been linked to four human deaths and many other violent incidents. For instance, a SeaWorld orca named "Tilikum" was involved in three human deaths. Marine biologists don't know why captive orcas are more violent, but stress likely plays a role.

Orcas are very social creatures and live in family groups called pods, which generally have five to 30 members. These pods are made up of related mothers and their descendants. Male orcas stay with their moms for life, while daughters may spend time away after having calves of their own. Pods often use their unique calls to communicate, but they can meet with other pods and sometimes come together to form even larger groups of over 100 orcas.

A female killer whale gives birth to one calf at a time every three to 10 years. Orcas work together to take care of the young.

Female killer whales live to be around 50 years old, but some orcas have lived up to 100 years. Males live shorter lives, usually dying by age 29. The oldest male orcas reach just 60 years.