Orca - The Killer Whale

Orca, also known as the “killer whale” is the largest living mammal of the Delphinidaw family. Although a whale, it is a sister to the dolphin and has genetic similarities.

However, they are the most dangerous predators in marine life. They survive in the icy waters of the Arctic as well as the tropical seas and adapt to various environments. They are social animals and can be found in close-knit communities of their own.

Scientific Classification

Kingdom	Animalia
Phylum	Chordata
Class	Mammalia
Order	Artiodactyla
Family	Delphinidae

Species

Orcas are classified as a species within the genus Orcinus. Researchers have categorized the Orcas into several types based on their distribution and habits. They can be categorized into various races or subspecies according to their lifestyle. Here are a few types of Orcas based on their ecological importance:

Northern Hemisphere

Type	Description
Resident Orcas	Common in the North Pacific region in small home ranges, mostly feeding on Salmon.
Bigg’s Orcas	They travel in seas between South Carolina and the Arctic in close-knit families, feeding on seals and gray minkewhales.
Offshore Orcas	These are rare types found on the outer continental shelf in large groups, feeding on fish and sharks.
North Atlantic (Type I and II)	Found in Norway, Iceland, and Scotland, with distinct features like back-sloping eye patches, feeding on whales and dolphins.

Southern Hemisphere

Type	Description
A	Found in the Southern Ocean with other whale migrations, feeding mainly on minke whales.
B	Small: They live in the Antarctic Peninsula and feed on penguins. Large: These are larger whales with yellowish skin, feeding mainly on seals.
C	These are the smallest Orcas of the Arctic. and have a dark cape across their body. They feed largely on Antarctic toothfish.
D	They also consume toothfish and are rarely seen across the Subantarctic region.

Description

Size and Weight: Orcas are huge species, with adult males around 20-26 feet long, and weighing over 6 tonnes. The females are relatively smaller around 16-23 feet in length and weigh around 3-4 tonnes. Newborn Orcas are over 7 feet long and weigh anywhere near 180 kg.

Fins and Tail: Males have elongated dorsal fins on their backs while females have slightly curved ones. These can be over 5 feet high. They also have paddle-shaped pectoral fins that help swim. The two-lobed tail has “flukes” with no vertebrae extending, creating force as they move across the water.

Snout and Teeth: Unlike other dolphin species, Orcas have a snout without the beak characteristic. Their conical-shaped teeth range from 40-56, each 3 metres long to grab their prey. Male Orcas have larger jaws, compared to females, and also have a stronger and wider occipital crest bone.

Skin and Coloration: Orcas are black and white whales. The body is mostly black on the top with distinct white patches on the bottom and sides. When born, the white-colored part of their body appears light orange or yellow which becomes clear white as they mature. Some Orcas also have gray or white saddle patches behind their dorsal fin.

Distribution and Habitat

Orcas are found across all marine regions, mostly around higher latitudes where food is abundant. Most of the population is found in icy regions like the Antarctic, but they also adapt to tropical and temperature marine environments. They are spotted in the Northeastern Atlantic, North America, California, Norway, Argentina, Alaska, and the Antarctic. Some freshwater rivers, like the Columbia River, are also home to these giant creatures.

The Orca population doesn’t follow any specific migration pattern. They move across waters based on their food and breeding requirements.

Diet and Digestion

Orcas are enormous apex predators. Although they have different dietary needs based on their size and regional habitat, Orcas need to consume 150-300 pounds of food, on average, to stay healthy. They prey on smaller mammals such as fish, seals, squids, sea lions, whales, and some seabirds. In colder regions, they intake larger quantities of food to provide heat and temperature to the body.

These killer whales do not chew their prey but swallow them as whole. The food breakdown starts at the stomach level where the food converts to nutrients absorbed by the intestines.

Behavioral Adaptations

Social Structure

Similar to elephants and primates, Orcas have a complex social structure. They interact in groups or “pods” led by senior females who no longer give birth. Each orca pod can have five or as many as 30 whales. Various pods also come together forming larger groups with more than 100 whales. The pod leader teaches young Orcas hunting and preying.

The pods are stable and the members stay with their family throughout their lives. They have close relationships and communication among them. However, some orcas do move around or migrate with their immediate family which includes mother and their children.

Hunting Behavior

They are at the top of their food chain and consume various marine animals. They commonly use pack hunting strategies and change those based on their prey and location. For example, they use echolocation to herd fish groups together into clusters to catch them at once. With their high intelligence, they can also plan complex attacks on larger sea animals such as seals and other whales.

Often, Orcas end up killing more prey than they consume due to their huge mouth. This surplus killing helps younger Orcas to understand the hunting techniques better and prey with the right method as they mature.

Communication

Orcas follow a unique dialect based on the pod they are a member of. They use clicking, whistling, and pulsating sounds to communicate with their fellows. This helps the pods stay together and coordinate their hunts. Those who feed on larger mammals are less vocal than those who consume the smaller ones.

Surface Behaviors

Besides their behavior within the marine environment, Orcas also have special surface behaviors such as spy-hopping, breaching, and tail-slapping across the water. These behaviors are to scare or stun the prey, communicate within communities, or sometimes remove parasites from their bodies.

Echolocation and Eyesight

While Orcas have excellent eyesight both above and below the water, they prefer using echolocation to navigate and find their prey. They not only make high-pitched sounds but can also listen to them from a distance to identify the shape, size, and distance of objects around them.

Reproduction and Lifespan

The reproductive cycle is unique and longer than other marine mammals. Females become sexually mature between 6-10 years of age; however, they start breeding when they are 14 years old. Males, on the other hand, become sexually mature between 10-13 years of age. They do not follow any specific mating timeline but most of it starts around the summer season. The pregnancy period lasts around 15-18 months, after which baby calves are born. A female Orca gives birth every 6-10 years.

Parenting is highly protective in that the mother and other females in the pod help in the nourishment of the newborn. The caring period lasts until the calf is 2 years of age. The children prefer to stay in the same pod alongside their mother and ancestors learning about social structures and hunting techniques.

Mortality Rate and Lifespan

Orcas can live up to 60-90 years of age if they stay healthy and maintain their dietary needs. Males on average live for about 30 years on average, whereas females can survive up to 50 years of age on average. The lifespan increases in wilder marine environments with abundant food and prey.

The survival rate of Orcas is around 50% in the first year they are born. They face the challenges of threats from other predators and human activities, decreasing their chances of survival. Once they reach maturity, they are more aware of the social structure and their surroundings and become stronger in survival.

Ecological Importance

Being at the top of the food chain, Orcas maintain several marine populations, such as seals, sea lions, and several other whales. Their ways of living also maintain the kelp forest habitats for sea urchins. A change in Orca’s behavior can have a great impact on the marine environment hence they are ecologically important for the water regions.

Conservation Status

In 2008, the IUCN declared that they did not have enough data on the exact population of Orcas. However, certain populations might be endangered. For example, the ESA has listed the Southern Resident population as endangered due to a lack of food sources such as Chinook salmon and increased human boating activities.

Fun Facts about Orcas

Orcas were named “killer whales” after some sailors found them hunting other whales in the sea.
They are extremely intelligent and have the second-heaviest brains among marine mammals.
Orcas are the fastest marine mammals and can swim at a speed of 34 mph.
Similar to dolphins, Orcas also sleep with one eye open.

Cultural Significance

These killer whales have been found in several mythologies and traditions of various cultural societies. They are considered symbols of wisdom, strength, and protection. Due to their social structures, they are shown as companions of the sea kings with supernatural powers. Orcas are also depicted in artworks and ritual accessories as pieces of freedom, independence, and autonomy.

FAQs- Frequently Asked Questions

Q: Why is an orca called a killer?
Orcas are called “killer whales” because they have been observed hunting and killing large prey, including other whales, which led sailors to name them “whale killers.”

Q: Are orcas friendly to humans?
Orcas generally do not pose a threat to humans in the wild and there are no verified cases of wild orcas attacking humans. They are often curious and social.

Q: Is orcas a killer whale?
Yes, orcas are commonly known as killer whales.

Q: What eats a killer whale?
Orcas have no natural predators as adults. However, calves may be vulnerable to large sharks and sometimes sperm whales.

Q: Are sharks afraid of orcas?
Yes, sharks, including great whites, are known to avoid or flee from areas where orcas are present, as orcas can hunt and kill sharks.

Q: Is it safe to swim with orca?
While orcas are not typically aggressive toward humans, they are powerful predators, so swimming with them in the wild is not considered safe.

Q: Who wins, orca or Great White?
Orcas are dominant over Great White Sharks and have been observed hunting and killing them.

Q: What is orca afraid of?
Orcas are at the top of the food chain and have no known natural predators.

Q: What is a sperm whale’s worst enemy?
Orcas are considered the sperm whale’s biggest natural enemy, especially when they hunt calves.

Q: Can you touch a orca?
Touching a wild orca is not advisable, as they are powerful animals. In captivity, it depends on specific regulations.

Q: What is an orca’s biggest enemy?
Orcas do not have natural enemies as adults, but human activities like boating and pollution pose threats to them.

Q: What are 5 interesting facts about killer whales?

Orcas can swim at speeds of up to 34 mph.
They use echolocation to hunt.
Orcas are the largest member of the dolphin family.
They live in social groups called pods.
Orcas are found in every ocean around the world.

Q: How intelligent are orcas?
Orcas are highly intelligent, with problem-solving abilities, complex social structures, and the ability to learn and mimic behaviors.

Q: What is stronger than an orca?
In the ocean, orcas are considered one of the strongest predators, but sperm whales are larger and can pose a threat.

Q: Is there a difference between killer whale and orca?
No, “killer whale” and “orca” are the same species.

Q: Which is bigger, an orca or a Megalodon?
Megalodon was much larger, estimated to be around 60 feet in length, while orcas can reach about 26 feet.

Q: Do megalodons still exist?
No, megalodons are extinct.

Q: Do megalodons eat orcas?
Megalodons, when they existed, might have preyed on large marine mammals, but they are extinct and have never encountered modern orcas.

Q: Why are orcas called killer whales?
Orcas were observed hunting and killing other large marine animals, including whales, which is how they earned the name “killer whale.”

Q: What eats orcas?
Orcas have no natural predators, but young calves could be vulnerable to large sharks or other threats.

Q: Do orcas protect humans?
There have been accounts of orcas protecting humans from sharks, but these instances are rare and not well understood.

Q: How friendly is an orca?
Orcas are generally not aggressive toward humans and can be curious and social, but they are still wild animals.

Q: What is the IQ of an orca?
While not measured in terms of human IQ, orcas are considered highly intelligent, on par with dolphins and great apes.

Q: Can you swim with orcas?
Swimming with orcas is not recommended in the wild due to their size and strength, even though they are not typically aggressive to humans.

Q: Do orcas have an enemy?
Orcas have no natural predators, but human activities like pollution and hunting can harm them.

Q: What is the orca afraid of?
Orcas do not have any natural fear of predators due to their position at the top of the food chain.

Q: What is a whale’s worst enemy?
For most whale species, orcas are their biggest natural threat.

Q: Do sperm whales eat orcas?
No, sperm whales do not eat orcas.

Q: Can orcas lay eggs?
No, orcas are mammals and give birth to live young.

Q: Do orcas get pregnant?
Yes, female orcas get pregnant and have a gestation period of 15-18 months.

Q: What animal kills sperm whales?
Orcas are known to attack and kill sperm whale calves.

Q: Has a sperm whale ever killed a human?
There is no confirmed case of a sperm whale killing a human.

Q: What is female sperm called?
Female gametes are called eggs or ova.

Q: What is the longest living whale?
The bowhead whale holds the record for the longest lifespan, living up to 200 years.

Q: What animal can survive 1000 years?
No known animal can survive 1000 years.

Q: Can whales live 500 years?
No whale species is known to live for 500 years.

Q: What whale can live for 200 years?
The bowhead whale can live for up to 200 years.

Learn More About Orcas

On this page, you are invited to explore our articles about the fascinating lives of orcas, also known as killer whales.

These articles answer common questions about orcas, including their diet, social structure, hunting behavior, reproduction, and their interactions with humans and other marine animals.

Scroll down to learn more about the unique characteristics of orcas and discover why they are considered one of the most intelligent and powerful predators in the ocean.