Orca Facts – Did you know?

The more we know, the more we understand and will be moved to take action to protect and rebuild the southern resident orca population. Photos by Rachael Merrett

Orcas have been roaming oceans for approximately 6 million years.

That’s 30 times longer than humans! However, over the past 200 years, human activities have contributed to several orca populations becoming endangered. Orcas are especially threatened by food shortages, chemical pollution, and increasing noise in the ocean.


There are at least 10 different eco-types of orcas in the world.

Orca are found in every ocean around the world with the greatest number of different eco-types found in Antarctic waters. Different eco-types have evolved over millions of years as the genetics of each population became more and more segregated due to a lack of interbreeding between populations.


Orcas have the second-largest brain of any animal in the world.

Killer whale brains weigh up to 15 pounds. Large brains paired with extreme amounts of folding or gyrification means things like language, memory and emotional capacity are highly developed, allowing them to develop rich culture. (Sperm whales have the largest brains).


The mortality rate of orcas is up to 50% in the first year of life.

High toxin levels are passed from mother to offspring via breast milk, and the calves are highly susceptible to poisonous chemicals. To help save orcas from extinction, we have to eliminate the use and discharge of these pollutants worldwide in order to improve the water quality for the orca.


Average adult resident orcas eat approximately 385 pounds of salmon daily to stay healthy.

Chinook salmon are the main source of food but they’ve have had consistently low spawning returns for several decades. A lack of food means orcas may starve to death.


Every orca is individually identifiable because they each have a unique dorsal fin and saddle patch.

Resident orcas can have an open or closed saddle patch on either side of the dorsal fin. They are white or grey and can have a black shape within them. Transient killer whales have only closed saddle patches that are solid grey to white in colour in varying shapes.


Southern resident orca J-2, known as Granny, was the oldest known killer whale in the world.

She passed away in October 2016, at the age of 105. Due to a lack of food and the effects of toxic contamination in their bodies, southern resident killer whales are passing away before reaching their life expectancies of 60-80 years for females, and 40-60 years for males.


More than 630,000 tons of fishing gear is lost, abandoned or otherwise discarded in the world’s oceans every year and this is an entanglement risk to orcas.

Derelict fishing gear poses a serious threat to marine organisms of all kinds. Entangled whales can be severely injured, have their fins amputated, or even die. We need to clean up our oceans to protect all wildlife.


Every orca population has its own unique language that no other orca population understands.

Losing the southern resident population would mean the loss of an entire orca language, culture and unique genetic community that has evolved for millennia. Action must be taken immediately to prevent this tragedy from happening.


All whales, including orcas, are born with whiskers.

The calves lose this facial hair soon after birth, but the hair follicles remain visible.

Baby orcas are born black and peachy-orange in colour; they’re not born black-and-white.

Scientists theorize this is because babies do not have a thick blubber layer yet, therefore the blood vessels near the surface of the skin give infants this colour pattern. Most take the black-and-white colour around their first birthday.


Because orcas are the oceans top predators, they’re one of the most contaminated animals on the planet.

Chemicals such as DDT, and PCBs and PBDEs (human-made industrial chemicals that don’t break down in nature) bioaccumulate or become highly concentrated through the food chain, and are stored in the fat tissue of orca. Studies show that orcas are experiencing problems with reproduction, development and proper immune system function due to these contaminants.


Orcas have a unique region in their brains.

It’s one that doesn’t exist in the brains of humans or other land mammals. Orcas have three lobes in their brain’s paralimbic system, whereas humans have only one. Scientists speculate the orcas lobes may be responsible for spatial memory and navigation.


A mother orca’s death greatly affects the mortality rate of her sons.

Males under the age of 30 experience a tripling of the annual mortality rate compared to other males in their age group if their mother passes away. Males over 30 years of age have an 8-fold increase in annual mortality rate if they lose their mom. Mothers are very important to the survival of killer whale communities!


The Exxon Valdez oil spill that occurred off the coast of Alaska in 1989, may have contributed to the death of 11 of the 22 Chugach transient orcas.

Scientists speculate that the orcas suffered from physiological damage from breathing hydrocarbons and consuming oil-covered seals. Closer to home, the increased tanker traffic in the Salish Sea poses a huge threat to the survival and recovery of southern residents.


There are countless stories worldwide of orca saving humans.

From leading boaters through the fog to rescuing children who were drifting out to sea, killer whales have shown great empathy for humans in trouble. Now it’s our turn to return the favour and help save the orca from extinction.


If unraveled, the small intestine of an orca would stretch the length of a Boeing 737-500.

That’s about as tall as a 10 storey building or 31 metres. Marine mammals who live in cold waters have small intestines that are very long, which may help them maintain body heat through processing food, which means more internal heat is being generated.


Killer whales keep half their brain awake while they sleep.

It is called unihemispheric slow-wave sleep, and they must rest this way because they are conscious breathers—they choose to surface to breathe. If they were to shut down their entire brain to sleep, they would drown. While resting, orcas still move, surface and monitor their environment.


Orcas receive sound through their lower jaw.

Sound waves travel to their inner ear and into their brain, where detailed images of their environment are formed. The ability of killer whales to hunt, communicate, and navigate depends on sound, and it’s being threatened by our increasingly noisy oceans.


Southern resident Onyx (L-87) is the only known resident orca to have “switched” pods.

After Onyx’s mother passed away, he attached to the matriarchs of the K-pod. When those passed away, he moved to the J-pod where he attached first to Spieden (J-8), and then to Granny (J-2). Today, he travels with Princess Angeline (J-17).


Humans, great apes, elephants, whales, hippos, manatees and walruses are the only animals that share a special type of cell in our brains.

They are called spindle neurons, and they’re responsible for tracking social interactions, performing certain intellectual and emotional functions, and they allow us to have feelings about other’s feelings.


Southern resident killer whales were the most highly targeted population of whales during the live capture era for captivity.

Over 40% of the population, approximately 60 whales, were removed during the 1960s and 1970s, which caused devastating effects on the structure of these families.


Orcas, like other whales, have special mucous in their lungs.

This mucous allows them to re-inflate their lungs after they collapse during deep dives. This can cause whales to have “stinky breath”!


Military sonar and underwater explosives can cause permanent damage or death to an orca.

When the shock waves hit the orca, blood vessels inside his/her body can burst and cause hemorrhaging, which leads to death. Orcas need safe, quiet places to live.


Orcas value sharing.

Females share all the fish they catch; sharing most with their offspring. Male killer whales only share their food about 15% of the time, and usually with their mothers. Pods need enough food so they can stick together, and help feed each other.


North Pacific transient killer whales are considered the most genetically distinct of all the world’s killer whale eco-types.

The North Pacific has three eco-types: residents, transients, and offshore killer whales. Each type is genetically distinct, with unique languages, cultures, prey preferences and hunting strategies.


Orcas produce sound by a process known as echolocation.

They do this by forcing air through their nasal passages, and then amplifying and projecting the sound through a fatty area of their head called the melon. Orcas have the most powerful and sophisticated echolocation of any animal on Earth.


Orcas have the longest gestation period of any whale.

Pregnancies last between 15-18 months, and females on average have a calf every 4-8 years. Females go through menopause in their early forties, but remain an integral part of the family unit.


Southern resident killer whales have 5 times higher toxic loads than harbour seals in the same area.

And transient killer whales have as much as 15 times the toxic load of local seals, as they further concentrate toxins from the mammals that they eat. (Resident orcas eat salmon, which don’t contain as many toxins).


There are only 78 southern resident killer whales, who call the Strait home.

The population has decreased by over 10% since 2003. A small population leaves them vulnerable to catastrophic events, such as oil spills, while low genetic variability can lead to inbreeding depression. Southern residents need protection now or soon it will be too late.

Learn more about what you can do to make a difference!