Killer Whale

Orcinus orca

With sleek black backs and bright white bellies and eye patches, killer whales, or orcas, are easily distinguishable from other aquatic animals.

Orca

Pair of orcas leaping in Canada. Photo by slowmotiongli / iStock.com.

One of the ocean’s largest predators, male orcas can grow to 9.5 m (32 ft) in length, while females are slightly smaller at 8 m (23 ft).

They live primarily where the water is cold but can live anywhere from the polar regions right up to the equator. This massive range makes orcas the most widespread of all sea creatures.

What Killer Whales Eat

True to their name, killer whales are effective hunters. They prey on seals, sea lions, fish, sea birds, turtles, octopuses, and squid.

Orca hunting penguin

Killer whale chasing a gentoo penguin in Antarctic waters. Photo by S_Lew / iStock.com.

Orcas will even attack other whales, including the enormous blue whale which can measure over three times their size.

They have also been known to breach the surface to grab sea lions and seals, even partially jumping onto ice floes to reach their target.

How Killer Whales Hunt

Killer whales hunt in pods, or groups, in a way similar to wolves. They circle their prey and force them into smaller areas before attacking.

Once cornered, the orcas take turns biting and ramming their prey.

Orca

Photo by sethakan / iStock.com.

Echolocation

Sending sound waves that travel underwater, killer whales use echolocation as a means for hunting. The reverberating sound provides information about an object’s location, size, and shape.

They also use echolocation as form of communication. Each pod has a distinctive sound it uses to communicate among its members.

Killer Whale Pods

There are thought to be three types of pods: transient, resident, and offshore.

Transient pods are constantly on the move following food sources. Resident pods generally stay in one area close to shore, while offshore orcas prefer the open waters.

Currently, scientists are not clear as to why there are contrasting pod behaviors. Some believe it is because there are actually several species of orca, but more research must be conducted in order to test that theory.

In resident pods, killer whales of both genders will live with their mothers for their entire lives, forming matrilines. In this way, resident pods consist of very tight, stable bonds and can comprise of 10-50 whales.

Southern Resident orca pod

A pod of Southern Resident orcas in British Columbia, Canada. Photo by cullenphotos / iStock.com.

Offshore pods are also large, made up of 30-60 whales. Transient pods, on the other hand, tend to be smaller (around 2-5 whales), as offspring will generally leave the group when a sibling is born.

Orca Reproduction

Mating can take place at any time of year and only occurs between members of different pods. After 17 months of gestation, calves are born in the water tail first. Female orcas can give birth every 3-10 years.

Newborns are very carefully protected within the pod. Often younger females will help new mothers protect their calves. Killer whales are also known to shelter injured or ill members of their pod from danger.

Killer whales live an average of 30 to 50 years in the wild.

Orca

Group of orcas with calf. Photo by slowmotiongli / iStock.com.

Conservation Status

At present, the IUCN Red List does not have enough data to provide a conservation status for killer whales.

But the Southern Resident population of orcas is listed as endangered under the United States Endangered Species Act.

Orcas are susceptible to threats like pollution, overfishing of their prey, and habitat infringement.

What You Can Do to Help

You can help orcas by spreading awareness about their special abilities to hunt, communicate, and live cooperatively. Write to your legislator about preserving their ocean habitat and keeping it free from pollution.

Orca Range

Orca range map

Orcas can live anywhere from the polar regions right up to the equator. This massive range makes orcas the most widespread of all sea creatures.

More Orca Resources

Quick Fact Sheet
Orca

Common Name(s): Orca, Killer Whale

Scientific Name: Orcinus orca

Animal Type: mammal

Size: 8-9.5 m (23-32 ft.) long

Weight: 5,550 kg (6 tons)

Lifespan: 30-50 years

Conservation Status: Data Deficient

About the Author

P.A. Smith is a middle school Language Arts teacher. He is also a contributing editor of My House Rabbit.