Orca

The orca (Orcinus orca), or killer whale, is a toothed whale and the largest member of the oceanic dolphin family. It has a black back, a white belly, and white patches around the eyes. Orcas live in many parts of the world's oceans, from the cold Arctic to the Antarctic regions, but they are most often seen in cooler coastal waters.

As apex predators, orcas eat many kinds of food and often hunt together. Different groups may eat fish, sharks, rays, or even other marine mammals like seals and dolphins, and whales. They are very social animals, living in family groups called pods. They use sounds and hunting tricks that they learn from older members of their group.

Orcas have interested people for a long time. Indigenous cultures respected them, while in the past, some Western cultures were afraid of them. In the 1960s, orcas began appearing in marine parks, where they learned to do tricks. This brought more attention to the species, but it also made people worry about their safety. Orcas are usually not dangerous to humans in the wild.

Naming

Orcas are often called "killer whales" because long ago, sailors saw them hunting larger whales. Today, many people prefer the name "orca." The name comes from a Latin word meaning "a large-bellied pot." It was used by Ancient Romans to describe these animals.

Sometimes orcas are also called "blackfish," a name shared with a few other whale-like animals. Another old name for them was "grampus," but this word is rarely used now. It’s important not to confuse this with a different kind of dolphin called Risso's dolphin.

Taxonomy

The orca, also called the killer whale, is the only living species in its genus, Orcinus. It was first described by the famous scientist Carl Linnaeus in 1758. Orcas belong to the oceanic dolphin family, which has been around for about 11 million years.

There are several types of orcas, and scientists are still learning about them. Some orcas eat mostly fish, while others hunt marine mammals. Some think certain groups of orcas might be different species, but more study is needed to know for sure.

Characteristics

Orcas, also called killer whales, are the largest members of the dolphin family. Males are usually between 6 to 8 metres long, and females are a bit smaller, from 5 to 7 metres. Both males and females have black and white colouring, which makes them easy to recognise. Males have larger dorsal fins and pectoral fins than females.

Orcas have great eyesight and hearing. They also have a special skill called echolocation. This helps them find food underwater by making clicks and listening for echoes. They have thick blubber to stay warm in cold water. Each orca can be identified by the shape of its dorsal fin and the pattern of its saddle patch. This helps scientists learn about their lives and social groups.

Range and habitat

Orcas live in all oceans and most seas. They are found in many places, especially in cooler areas near coasts. Some well-studied places include the coasts of Iceland, Norway, the Valdés Peninsula in Argentina, the Crozet Islands, New Zealand, and parts of the west coast of North America, from California to Alaska. They are most common near the Norwegian coast, the Aleutian Islands, the Gulf of Alaska, and near Antarctica.

In the Antarctic, orcas can be found near the edge of the ice and sometimes even go deeper into the ice. They visit Arctic waters but only during certain times of the year. Sometimes, they even swim far up rivers, like the Columbia River in the United States. Each summer, the same orcas appear off the coasts of British Columbia and Washington, but where they go the rest of the year is still a mystery.

Feeding

Orcas are apex predators, which means they have no natural predators. They are often called "wolves of the sea" because they hunt together in groups. These clever animals eat many different kinds of food, including fish, squid, mammals, birds, and even sea turtles.

Different groups of orcas might focus on certain foods depending on where they live.

Some orcas mainly eat fish, like salmon and herring. In places like Norway, they follow herring during their migration. They have special ways to catch fish, such as working together to herd herring into a tight group and then stunning them with their tails before eating. Other orcas eat marine mammals such as dolphins, porpoises, seals, and even larger whales like sperm whales and grey whales. They work together to chase and catch these animals. Orcas also eat birds, though they often just leave them.

Behaviour

Orcas, also known as killer whales, spend their days foraging for food, traveling, resting, and playing with each other. They often jump out of the water or slap their tails on the surface to talk, play, or clean themselves. Orcas can swim very fast, up to 35 mph. They sometimes swim close to porpoises and dolphins.

Orcas live in complex social groups, like some other animals. These groups are based on family ties, with the oldest female, called a matriarch, leading. Orcas often stay with their mothers their whole lives. These family groups sometimes come together in larger groups called pods. Some orcas, called transients, leave their family groups more often.

Orcas use sounds like clicks, whistles, and calls to find food and talk to each other. Each family group has its own set of calls, which helps them stay connected. Orcas are very intelligent and can learn new skills. They have been seen using tools and solving problems, showing their cleverness.

Life cycle

Female orcas start to grow up around 10 to 13 years old. They can have babies until they are about 40. Some females live for many years after they stop having babies. Female orcas usually live for about 50 to 80 years.

Male orcas can have babies with females from other groups. This helps keep the group healthy. Males start to grow up at 15 but usually have babies when they are about 21. They can keep having babies until they are about 59. Male orcas usually live for about 29 to 30 years, but some can live up to 50 to 60 years.

Conservation

In 2008, the IUCN changed how we think about orcas and their conservation status. Some kinds of orcas might be endangered species. Big dangers to orcas include less food, pollution, big oil spills, and habitat disturbance from loud sounds and boats.

Orcas can be harmed by harmful chemicals in their bodies. In the Pacific Northwest, fewer salmon, which orcas eat, have hurt orca groups. The southern resident group in the Puget Sound area is in trouble because of this. Underwater noise from people also bothers orcas.

Relationship with humans

Indigenous cultures

The Indigenous peoples of the Pacific Northwest Coast have included orcas in their art, history, and spiritual beliefs for a long time. For example, the Haida saw orcas as powerful ocean animals, with stories of them living in underwater homes. The Kwakwaka'wakw believed orcas ruled the undersea world. Many coastal groups see orcas as important spiritual beings and family relatives.

Other cultures also respect orcas. The Maritime Archaic people of Newfoundland made stone carvings of orcas thousands of years ago. The Siberian Yupik tell stories of orcas appearing as wolves and helping hunters. The Ainu people of Hokkaido and nearby islands honored orcas in their traditions.

Attacks by wild orcas on humans and animals

In Western cultures, orcas were once thought to be dangerous. But there are very few proven attacks on humans by wild orcas, and none have been fatal. Examples include orcas moving ice floes with a dog team on them, a surfer being bitten but escaping, and a boy being bumped while playing in water.

Orca attacks on sailboats and small vessels

Since around 2020, some orca pods have started to interact with sailing boats near the southern tip of Europe. These meetings have sometimes damaged or sunk boats, with at least 15 reports in 2020. Scientists are not sure if this behavior is playful, defensive, or linked to past events.

Modern Western attitudes

Views on orcas changed a lot in the 1960s and 1970s. The capture and study of a whale named Moby Doll showed that orcas could be calm and friendly. Research showed their complex social lives and strong family ties. Public interest grew so much that orcas became cultural symbols, leading to protections and efforts to return captured orcas to the wild.

Whaling

Orcas were not often hunted until larger whale numbers went down. Between 1954 and 1997, countries like Japan and Norway hunted thousands of orcas. International rules now limit hunting, though small amounts are still allowed in places like Indonesia and Greenland.

Whale watching

Watching orcas from boats is very popular but can bother the whales. Many boats follow the same group of orcas for hours, creating air pollution that may harm their health. Rules now require boats to stay farther away from the whales.

Captivity

Orcas are often kept in aquariums and aquatic theme parks because of their intelligence and size. However, many think this is unfair to the whales, as their lives in captivity are shorter and more stressful than in the wild. Some parks have stopped breeding orcas and doing shows, but others still continue these practices.