The toothed whale suborder is comprised exclusively of whales, dolphins and porpoises that are born with teeth instead of baleen plates.
While the killer whale carries the name “whale” as part of its description this marine mammal is actually considered a dolphin.
In addition to being known as the killer whale these marine mammals may also be referred to as the Blackfish or the Orca.
Killer whales are one of the most well-recognized animals in the world and are easily spotted by their large size and distinct black and white color pattern.
In fact the killer whale is the largest animal in the dolphin family and is one of the only known cetaceans to attack sharks, whales and other large marine mammals, which helps explain why they are so well known and popular.
These dolphins are extremely intelligent animals that are well-organized and follow highly complex social structures within their pods, which often consists of large groups of family members that can span several generations.
In fact the social structure of killer whales is considered one of the most stable social structures of any animal species and is sometimes compared to the cultures of humans and elephants.
Having no known predators the killer whale is known as an apex or alpha predator, which means it is able to hunt freely without fear of being attacked by another marine animal.
In other words when it comes to marine mammals the killer whale is at the top of the food chain.
Note: Cetaceans include all species of whale, dolphin and porpoise.
Physical Characteristics and Appearance
As stated earlier the killer whale is the largest animal within the dolphin family.
At full maturity the male killer whale will usually grow to an average length of 20 – 26 ft. long and weigh an average of 8,000 lbs. – 12,000 lbs. while an adult female killer whale will grow to an average length of 16 – 23 ft. long and weigh between 3,000 lbs. – 6,000 lbs.
The largest recorded killer whale measured in at 32 feet and weighed over 10 tons.
In terms of physical appearance killer whales have black backs, white chests and sides and white circles above and behind their eyes.
Depending on the pod the killer whales belongs to their dorsal fin may either be long, tapered and pointed in a triangular fashion or rounded and curved towards the end.
The skull is somewhat oval shaped and the beak is extremely short and rounded at the end.
In order to capture their food the killer whale has a powerful jaw with teeth that are able to tear apart the flesh of their prey and withstand the jolting, wiggling and hurtling movements of prey that are trying to escape.
Because the killer whale belongs to the toothed whale family these dolphins are born with a single blowhole instead of the two that baleen whales possess.
These marine mammals have a stocky build that is widest in the center and tappers off towards the upper and lower ends of the body.
To assist with swimming the flippers are paddle shaped with rounded ends and the flukes are tapered back and pointed at the end like a wide triangle or pyramid.
Diet and Hunting Methods
In order to maintain their energy killer whales will feast on small aquatic life forms such as fish, squid and octopus as well as larger marine animals such as sea lions, seals, seabirds, penguins, whales, dolphins and even sharks.
Depending on the region the killer whale lives in their diets can change dramatically.
For example killer whales that live in resident pods typically consume a diet consisting of fish and squid while killer whales that live on transient pods will primarily consume marine mammals.
Offshore pods also tend to stick to a diet consisting of fish, but physical scarring on these marine mammals shows that they may hunt other marine mammals and sharks as well.
Just as with the types of prey they hunt the killer whales food intake can also vary significantly from one group to another.
Depending on their age and diet killer whales can eat anywhere from 2% to 10% of their body weight in food on a daily basis.
One study suggests that calves (newborn dolphins) will tend to eat a higher percentage of food in body weight than adult dolphins in order to help them grow and develop.
In order to obtain their meals killer whales can often be observed hunting in groups.
While hunting for food these marine mammals will base their strategies on the prey they are hunting and use different methods to capture different prey.
When hunting dolphins killer whales have been observed working in spaced out groups to isolate the dolphin and eventually exhaust it until the dolphin was out of energy and no longer able to run.
Some dolphins are really fast swimmers so in order to capture these marine mammals the killer whales will take turns chasing it in order to conserve their own energy while the dolphin slowly tires out.
Once the dolphin is no longer able to run the killer whale may rush in and charge the dolphin, hit it or flip it into the air in order to immobilize it before going in for the kill.
When hunting sharks one group of killer whales may attempt to distract the shark while another killer whale sneaks up from behind or beneath the shark to flip it upside down.
Once the shark is flipped over it is unable to attack or move leaving it defenseless and an easy meal.
This both minimizes the killer whales chances of being hurt while maximizing their chances of success.
As stated earlier killer whales have also been observed hunting large whales.
In these situations a group of killer whales may attempt to distract a whale pod and separate a young defenseless child from its parents in order to obtain a meal.
In addition to hunting in groups killer whales may also use echolocation to capture their prey.
When searching for food underwater or at night echolocation becomes the dominant sense for locating pray and maneuvering around objects in the dark ocean.
Since echolocation uses sound and not sight it acts as a primary sense when vision cannot be used.
In fact there are several dolphins species that are known to use echolocation as a replacement to vision since they have very poor eyesight.
Some interesting animals and species found in the stomach of killer whales include:
Habitat and Migration
Although killer whales are often found living cold ocean waters these marine mammals can be found in all of the worlds major oceans from the Antarctic to the tropical regions of the world both in coastal and offshore waters.
Unlike marine mammals that follow certain migration patterns during mating and feeding seasons the killer whale tends to migrate to wherever their food supply migrates to.
In other words rather than migrating to find a mating partner killer whales are more interested in following their food supply throughout the year, especially in areas where their primary diet moves as the seasons change.
In some regions the migration of killer whales are influenced by fish, squid and various other small pray, while in other locations they will move in response to where seals, sea lions or other marine mammals migrate to.
Social Structure and Communication
The complexity of the social structure of killer whales can be compared to elephants and humans.
Depending on the type of killer whale (resident, transient or offshore) these marine mammals may hunt in pods (groups) of anywhere from 6 to 40 members.
In larger pods as many as four generations of family members can be seen traveling within a single group which can include the children, parents and grandparents of a single family.
As with humans, wolves and elephants killer whales are very protective of their young and will attack outsiders if they feel threatened.
When traveling in large groups individual killer whales will leave their pods only for short periods of time (a few hours) to forage for food or mate.
This can occur when an adult killer whale of a small pod needs to feed his/her children.
The killer whale may go off and search for a marine mammal such as a seal or sea lion and bring the food back in order to feed the rest of the pod.
Larger groups of killer whales may hunt in groups and use complex hunting methods to isolate, attack and capture their prey.
When it comes to socializing with one another communication typically involves using a series of clicks and whistles to inform other dolphins of important information.
The amount of vocal communication that occurs between a group of killer whales varies from one pod (resident, transient or offshore) to the next.
Communication may also occur using physical gestures such as light touches, jumping out of the water, lunging, charging, lobtailing or spyhopping.
The combination of verbal and physical communication allows these marine mammals to display a wide range of interests, wants and needs to one another.
Reproduction and Lifespan
When it comes to giving birth the average gestation period (the period between fertilization and birth) for a female killer whale often lasts between 15 – 18 months (average is about 17 months).
During delivery the child is often born tail first in order to minimize its chances of drowning, however there are cases of killer whales being born head first.
After birth the young killer whale will be nursed by his/her mother and fed a diet of thick fatty milk, which the child receives by suckling from its mothers nipple.
The fatty milk possesses all of the nutrients the child needs during its early stages of life in order to develop into a healthy young dolphin.
Once the child reaches a certain level of development the child may begin hunting for food with other pod members or may be fed solid foods (such as seals or sea lions) by its parents.
After a number of years the child will eventually develop into a young adult and begin reproducing offspring of its own.
Both the male and female killer whales mature around the age of 15 although males usually start reproducing around the ages of 19 – 21.
After reaching sexual maturity and becoming impregnated the female killer whale will usually produce a single offspring once every 3 – 5 years until they reach the age of 40 or are no longer able to reproduce.
On rare occasions these marine mammals may give birth to twins, but this is extremely rare.
In terms of lifespan killer whales can live for an average of 50 to 80 years with females tending to have a longer lifespan than their male counterparts.
Killer whales living in captivity however are estimated to have a lifespan of less than 25 years.
When it comes to living in captivity killer whales are one of the most popular marine mammals that are known to inhibit captive environments making them a serious study for marine biologists and conservationists.
Due to the killer whales large size, intelligence, playfulness and ability to be trained these marine mammals have become a very popular crowd pleaser at aquariums and aquatic theme parks.
While they are generally adored by spectators and trainers some activists, organizations and conservation societies argue that keeping killer whales in captivity creates high levels of stress among the killer whales because of their need for social interaction, open space and family.
For killer whales being able to live in natural open spaces is extremely important for their health and well being.
Like humans and elephants these marine mammals also crave social interaction and family in order to survive and thrive.
In fact the average life expectancy of killer whales can be reduced by as much as 2/3 when living in captivity causing many of them to live only until their 20’s as apposed to those that live in the wild for 50 – 80 years.
While held in captivity there have also been a number of recorded cases of killer whales attacking their trainers and pulling them underwater with at least one attack leading to the death of a trainer.
Although their have been attacks on trainers these situations tend to be rare and additional steps have been put into place in order to prevent future situations.
Killer whales in the wild
Despite the fact that killer whales are known for consuming other mammals they do not appear to pose a threat against humans.
For the most part killer whales do not appear to be interested in hunting or pursuing humans.
In the wild there have only been a handful of attacks recorded by killer whales due to the killer whale mistaking a human for their normal prey.
Once the killer whale became aware of the fact that it was not their typical food the marine mammal stopped pursuing the human and moved on.
Although killer whales are known for their ferocious hunting methods the likelihood that a killer whale will attack a human is extremely low.
While the majority of killer whale attacks have occurred between a trainer and a killer whale during training at a marine park it is possible (however extremely rare) that an attack may occur in the wild.
In fact only a handful of cases have been recorded regarding killer whales attacking humans in the wild.
In many cases these attacks are the result of a killer whale either miss identifying a human for a marine mammal, the killer whale feeling threatened by an assumed attacker or the killer whale becoming aggressive due to being isolated in a small environment and separated from his/her family such as those held in captivity or at marine parks.
Even though these attacks occur on occasion many of these attacks are not the result of killer whales being naturally aggressive, but of killer whales either mistaking humans for other marine animals or becoming aggressive due to isolation or threats.
Interestingly none of these attacks resulted in the killer whale ever trying to eat or consume a human and only a small number of cases required stitching due to bite marks from an attack.
The only known recorded cases of a human being killed by a killer whale involve a killer whale pulling their trainer below the water causing the individual to drown.
Why killer whales are not interested in human flesh remains a mystery to scientists in marine biologist who studies these marine animals.
While it is unknown why killer whales are not interested in attacking or eating humans it is speculated that killer whales do not have a taste for human flesh and that we do not resemble any type of animal that they would normally bother attacking and consuming, therefore we are not considered a form of edible food.
Another assumption is that killer whales have a code of ethics in which they have moral respect for humans and therefore do not bother in trying to attack humans without a sufficient reason.
While killer whales do possess the ability to be vicious and naturally aggressive in many cases they can also be fairly friendly and cooperative.
This is often seen at marine parks were killer whales can be seen performing tricks and acrobatic feats through the commands of their trainers and although they’re often isolated from the natural environment in many cases killer whales are able to remain fairly passive and maintain a positive attitude.
While killer whales are known to be outgoing and friendly due to television and our understanding of them at marine parks and through other educational/entertainment exhibits it is always important to take caution when around these marine mammals and not try to interact or play with them in the wild as they can be unpredictable and if they feel threatened they may choose to defend themselves.