Orcas Explained
#10.
Orcas are actually dolphins Despite the fact that Orcas are commonly referred
to as killer whales, their actual biological classification is quite different.
The name killer whale was given to the creatures by sailors/ who observed their behavior of
targeting and killing actual whales in ferocious ways.
They were initially called whale killers.
However, over time, the name has flipped to what we know today.
A lot of people get confused about the biological identity of Orcas, mistaking them as shark
species, due to their appearance and hunting patterns, or whale species, due to their confusing
common name.
Although Orcas do fall within the loosely defined whale group, they are actually biologically
classified as dolphins with the Latin name Orcinus orca.
They have black and white coloration, are toothed/ and can be found in oceanic waters
all around the world, save for the Arctic and Antarctic regions and the Black and Baltic
seas.
They are carnivorous mammals, have an average lifespan of 50 to 80 years, and can grow between
23 to 32 feet, and can weigh as much as 13,000 pounds.
That s at least half the length of a bus/ and at least a quarter its weight.
#9.
Orcas use a special sense to hunt Most marine predators have a tremendously
potent sense of smell.
Take a shark, for instance, which has two-thirds of its entire brain dedicated to olfactory
acuity.
Sharks can detect tiny amounts of blood/ from a long distance away, at least a quarter-mile.
This makes it difficult for injured prey to escape.
Orcas, on the other hand, do not have such a powerful sense of smell.
In fact, they have no olfactory acuity whatsoever.
Yet, still, they have a reputation as a ferocious marine predator.
And so, how do they hunt?
Orcas have developed a special adaptation that takes advantage of echolocation.
Although echolocation, also called bio sonar, is thought to be the forte of creatures such
as bats, orcas, and other toothed dolphins, have heightened senses in that capacity as
well.
They detect the location and characteristics of prey and other objects in the water/ by
emitting clicks and listening for echoes.
They have a special organ in their brain capable of transmitting three different waves for
the best sensitivity.
#8.
Orcas have really big brains Speaking of an orca s brain, these creatures
have a really big brain size.
After sperm whales which have the largest brain of any animal at all orcas have the
second-largest brains of any marine animal.
Their brains can weigh as much as 15 pounds, which is half the weight of an entire Icelandic
sheepdog.
Although in the past, big brain size was thought to correlate with high intelligence, that
isn t quite the case anymore, and orcas might be more intelligent than their pretty massive
brain size suggests.
Orcas are really high up on the list of intelligent creatures.
However, you wouldn t know it just by judging the brain size.
Brains are made up of different types of cells which all perform different functions.
For example, sharks have a decent body-to-brain weight ratio, rivaling that of other mammals.
But since a third of the brain is dedicated to olfactory acuity, the weight doesn t mean
that much.
And so, although orcas have a brain size that is 2.5 times larger than the average of other
mammals, their cognitive abilities far exceed what is expected of them.
They have really impressive social, cultural, and echolocation abilities.
#7.
Orcas are the second most widespread animal in the world
Other than having the title of the second-largest brain among marine animals, orcas also hold
the title of the second most widespread animal in the world.
They can be found in all oceans and seas, although their population densities tend to
vary depending on the exact location and the exact depth.
Killer whales tend to prefer higher latitudes and coastal areas over pelagic environments.
The highest densities of these creatures occur in the northeast Atlantic around the Norwegian
coast, in the North Pacific along the Aleutian Islands, the Gulf of Alaska, and in the Southern
Ocean off much of the coast of Antarctica.
In these waters, one orca can be found per every 97 square miles.
They also migrate quite a lot, although, due to their low population numbers, their migration
patterns are poorly understood.
As recently as 2006, their numbers were estimated to be 50,000 worldwide, with 5,000 in the
Antarctic, 8,500 in the tropical Pacific, about 2,700 off the cooler northeast Pacific,
about 1,500 off Norway, and about 2300 in Japan.
Although these figures are low, it s more likely that there s little information available
rather than that these creatures are endangered.
#6.
Orca Clans Speak Different Languages This is one of the benefits that a large brain
affords these creatures.
Not only have they developed the basics of language, but the different orca clans speak
different languages.
Orcas are highly social creatures that stick together to hunt, mate, protect one another,
and migrate.
They stick to small family groups called pods, which, when placed together, form larger societal
groups known as clans.
Orcas communicate which each other using sounds and non-verbal gestures.
These include whistles, clicks, and loud broadband packets of sounds called burst pulses.
Communication is useful for warning each other of predators and prey.
It can also be used to establish higher societal functions, which we will touch on in a little
while.
In any case, since the orca language isn t that developed, neither are the dialects.
It would be best to think of them as different accents of the same language.
These dialects differ from each other in much the same way as Australian accents, American
Accents, and British Accents differ from each other.
Nonetheless, their existence showcases the intelligence and higher social dynamics of
these creatures.
#5.
Orcas go through menopause As, biologically speaking, the one purpose
of life is to reproduce more life, the vast majority of creatures stay sexually active
for much of their lifecycles.
However, there are some notable exceptions, including humans and orcas.
The evolutionary purpose of menopause in humans is to protect both mothers and newborns.
Births among older women are always difficult, with a high chance of miscarrying.
However, for killer whales, the reasoning is quite different.
Of their average lifespan of 50 to 80 years, males come into sexual maturity at 15 years
old, while it takes 21 years for females.
After mating and giving birth, the females go through menopause, living for long periods
without sexual activity of any kind.
This menopause occurs due to the habit of killer whales of staying in pods.
Because both sons and daughters remain in the pod throughout adulthood, older females
are increasingly related to everyone in the pod, and so they need to stop breeding lest
they breed with their offspring and share genes, which will weaken the gene pool.
Instead of doing this, females stick around and help by guiding and protecting young members
of the pod.
#4.
Orcas have evolved based on culture Evolution is one of the most basic laws of
biology.
At its most elementary level, it ensures that only living organisms with the best traits
for surviving their environment can breed and pass these traits down to newer generations.
For more intelligent creatures such as humans and orcas, the rules of evolution are a little
different.
Where intelligent creatures, who have managed to develop their own language and culture,
are involved, the rules of evolution are quite different.
They don t just depend on environmental pressures but on social and cultural constructs as well.
In 2016, a team of researchers studied the genetic material of different orca groups.
Lead scientist Andrew Foote and his colleagues discovered that genetic variations between
different orca pods coincided with distinctions in culture and group social behaviors.
To elaborate, this simply means that different orca pods hunt different types of prey in
different ways.
And these hunting patterns eventually led to observable differences between the genetic
material of these pod groups.
This is partially why different pod groups have different dialects.
#3.
Orcas are voracious eaters Killer whales are very greedy, and their greediness
manifests in two ways.
One, their diverse food palette.
And two, the amount of food they eat in a day.
Orcas eat just about anything, including fish, squid, marine birds, seals, sea lions, penguins,
sea turtles, sharks, and even other kinds of whales.
Their diet varies depending on the season, the ecotype of the orca, and their exact location.
However, irrespective of these factors, the average killer whale can eat 500 pounds of
food a day.
To satiate this massive appetite, Orcas tend to hunt in groups.
It helps that they have no natural predators and can spend 60% of their time looking for
food.
The hunting groups tend to focus on vulnerable whales who are with children or separated
from the group.
A hunting exercise on this scale can take as much as nine hours.
First, they chase whales to exhaustion.
Then they drown them by preventing them from resurfacing.
Then they eat them.
#2.
Orcas exhibit sexual dimorphism This means both males and females have different
physical characteristics.
These differences exist because males and females have different ways of life.
Males need only to hunt and mate, but females need to perform the function of childbirth,
child protection, and child-rearing.
While in most other marine species, females are larger to accommodate for these functions,
that isn t the case with orcas.
In fact, female orcas are smaller than orca males.
Males typically range from 20 to 26 feet long and weigh in excess of 13,000 pounds.
Females, on the other hand, range from 16 to 23 feet and weigh between 6000 to 8000
pounds.
Males have an impressively tall dorsal fin, which can grow up to 6 feet long, compared
to females whose dorsal fins measure up to 31 inches.
Other than that, most other features are the same, including the black and white coloration,
blunt snout, and sharp teeth.
#1.
Orcas bully and eat sharks Although great white sharks are thought to
be apex predators, they get bullied and eaten quite often by orcas.
Sometimes, after sharks go through the trouble of stalking prey, orcas show up and take the
catch away from the sharks.
In such situations, the sharks are happy merely to get away with their lives.
As mentioned earlier, orcas are known to eat sharks from time to time.
Killer whales hardly eat sharks unless they are having trouble finding less defensible
prey.
Because sharks aren t social creatures, orcas manage to take them down using the power of
teamwork.
In 2015, a charter operator known as Matt Waller observed with other divers in South
Australia how a team of orcas took down a great white shark by repeatedly slamming into
it.
Two of the orcas were calves, who were being taught how to hunt by their elders.
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