Killer whales, belong to the species of Odontocetes Cetaceans , Delphinidae family. They are considered as the most feared predators in the marine world. They got this denomination for being ruthless killers when it comes to hunt their prey.
Another sample of their sanguinarity, is that they prefer to choose animals accompanied by their offspring, since it make them vulnerable and slow to escape from the killer whales ferocious jaws.
The Orca or killer whale is the largest species of the delfinio group and the only one that exists of the genenera Orcinus. They are very smart mammals, which take advantage of this fact, to plan their attack strategy, and to get orientated into the water. They also learn easily different tricks and acts. For this reason they are frequently captured and marketed for recreational purposes. Their beautiful mixing of white and black colors, are very proper to be part of aquariums.
In spite these cetaceans are violent and aggressive in their natural habitat, they can be trained and make them docile, as much as the white whale beluga , which is very friendly and sociable. But it should be noted, that if they don´t feel comfortable in their environment, they may become irritable, unsociable and up to finish assaulting their caregivers.
In this article about killer whales, you will know much more about this interesting and intelligent cetacean.
Now, let´s start knowing better these whales through the following video….
Table Of Content
- 1 Origin Of The «Killer Whales Name»
- 2 Types of Killer Whales
- 3 Main Characteristics of The Killer Whales
- 4 Common Behavior of the Killer Whales
- 5 Reproduction
- 6 Communication
- 7 Alimentation Habits of Killer Whales:
- 8 Killer Whales And Their Attack Techniques
- 9 Attacks on humans
- 10 Killer Whales: Main Threats
- 11 Pathologies
- 12 Killer whales in captivity
- 13 Conservation of Killer Whales
- 14 Killer Whale: A wonderful species
Origin Of The «Killer Whales Name»
The name Orca was a term originally used by the Romans and it is very possible that it comes from the Greek language «ὄρυξ«, that makes reference to whale. The word «orc» originates from the ancient English, and it means sea monster, big fish or as it is currently called ork, which refers to whale.
However, the first who applied the term killer whales were Spanish fishermen and whalers. They used it to describe a cetacean that ferociously attacks others of the same species.
In 1846, the word Orca was established as the name of this marine species. Although at present the complement “killer” is still added ,to highlight its status as a fearsome sea predator .
Types of Killer Whales
According to researches conducted on killer whales, based on their physical contexture and behavior there are three types of Orcas:
According to their ecology, behavior and morphology;
These specimens are located on the coasts of the North Pacific, Canada and the United States. They stay in these area throughout the year, and when they migrate, they do it to near locations. They eat mainly salmon and on very rare occasions squid.
Residents Orcas live in complex groups of more than sixty individuals. They can be identified by having a dorsal fin, slightly curved and round at the tip. Resident Orcas have unique vocalization patterns and they only mate among them.
These killer whales live in small groups of ten or less individuals, and they displace at wider distances than the residents orcas.. They feed on other marine mammals and their dorsal fin is pointed and triangle shaped.
This type is made up of five to twenty individuals in a single herd, which swim together. They can be seen at distances of 15 km, close to the coast, and their diet consists of sharks. They are much smaller than the previous ones and their dorsal fin is rounded like the residents.
Types of Killer Whales in Antartica;
They are characterized by being black and white, having an average size compared to others whales of the same species. They feed on other whales of the family of rorquals.
These killer whales have a large patch around the eye. Their white portion has a yellowish tinge, so actually they are gray and feed on sealss.
These cetaceans are the smallest ones, and they displace in big groups of whales of the same species. They have an oblique spot around the eye, which makes the difference when comparing them with others killer whales. They have a grayish spot on the back and their white portion is also yellowish. Their diet is based on eating cod.
These whales move in large herds, of approximately 9 to 35 individuals per group. Although there are still no studies to prove their food preferences, it is suspected that they eat fish exclusively. They have a fairly small eye patch, which is another of their characteristics.
Main Characteristics of The Killer Whales
Know it´s time to know the disticntive characteristics of these creatures…
Appearance and Size
This cetaceans are characterized, by their robust appearance and their black and white color pattern. These features are magnified when they are adults, since in their youth, they may be confused with «seals” , because their white parts are not totally developed.
As for the whales calves , their white spots are actually yellowish. Another feature that distinguishes them from the other whales, is that they have a dorsal fin in triangular shape with a gray spot behind it, which is very similar to a saddle. Males can reach a length of 9 meters long and 5,500 kilograms in weigh. In the case of females, they are usually smaller, with only 7 meters in length and 3, 800 kilograms in weight
Since killer whales belong to the delphinidae family, they have their same characteristic . With a large skull which reaches 1 meter in length. Its temporal fossa is large and doesn´t look like a snout or beak, its size indicates the strength of the muscles of the jaw to catch its prey.
They can have 10 to 14 teeth in each mandibular quadrant, to make a total of 40 to 46 large teeth, with a blunt shape and slightly curved inwards.
As for the shape of the skeleton, it is large and robust. It has 50 to 54 vertebrae, and between 11 to 13 pairs of ribs, 6 of which are joined with the sternum.
The pectoral fins are different between males and females. In the case of males, they have a triangular and elongated shape; reaching 1.8 meters long. While the female have a rounded and curved fin at the tip, reaching only 0.7 meters.
The killer Orcas in general, have a perfect condition in terms of their senses. They have perfect vision inside and out of the water, and an excellent sense of hearing and touch. But like all cetaceans, they do not perceive odors due to their lack of sense of smell.
They have perfect echolocation system, like the humpback whale ; so they can detect the characteristics and position of their possible prey; as well as objects, through the emission of sounds that are captured when returning
Common Behavior of the Killer Whales
These creatures are grouped in herds of a maximum of 10 individuals forming groups of 35 to 65 Orcas. It is possible that the size varies according to the geographical arrangement, quantity, behavior and type of food found in the area.
Based on studies conducted to the different types of Orcas, their social organization is defined as follows:
Their social group is strictly matrilineal, and it comprises female with her offspring of both genders and their adult daughters with their babies whales. They maintain such a close relationship between them, that they almost never separate from their herd ; that do not exceed 5 or 6 individuals.
It is known that similar to the residents , they also maintain a matrilineal society made up a female with her offspring . The males stay with the mother for a long time, even when they are adults; but in general terms, it is common that the offspring get separated from the group permanently. They can mate with other killer whales of an offspring with different ancestors. Contrary to residents who only do it with their same lineage.
They have a style of vocalization, which is maintained as a way to communicate among them.
To date there is no study that can clarify the form of social organization of this group. However, it is known that they form groups of 20 to 65 individuals, and there is exchange with other groups different from them. Different specimen of Orcas are always coming and going.
There is few information about the reproduction of Orcas, and it comes from those who are in captivity.
In this sense we will start mentioning, that females reach sexual maturity between 6 and 10 years old; and males between 10 and 13 years old, when the dorsal fin reaches its maximum size. Females in captivity have proven, that they have heat cycles interspersed with moments of ovulate inactivity. These cycles vary in each species .
Males court females for a week, and it has been observed that they may copulate with pregnant orcas, even with those that are not in heat. In fact , they can even mate with females of other groups; if they belong to a family with the same vocal style.
The gestation period of females last between 15 to 18 months, giving birth a baby whale each birth, which take place mainly in winter.
Killer Whales breastfeed their babies inside and outside the water, for an estimated time of 5 minutes; so they need an approximate frequency of 35 times a day. This way the optimal growth of the calf is ensured, since the death in captivity of this species is quite high.
The Orcas have a communication system based on vocalizations of sounds, which represent the basis of their social structure. Like almost all cetaceans, they depend on sound to orient themselves and identify objects, prey and other sounds that are found in the water.
To perform these vocalizations, the Orcas expel air through their nasal cavity, propelling it forward through the melon. This principle is known as echolocation, and it consists in recognizing everything surrounding the animal, through the sound waves that bounce against the obstacles of the environment, which are received again. Then the brain makes a figure based on the intensity of these waves.
Most vocalizations are acquired by imitation; so the hypothesis of a genetically inherited attitude is unlikely.
There are three ways of communication that have been detected in these species;
These sounds are emitted one by one or in sequence; usually for orientation purposes, and to locate objects and prey in the water. There are evidences that indicate, that they also do it as a form of interaction between them.
These are produced, to establish relationships and as a language among orcas. However, they are unlikely to whistle while moving or to locate food.
The so-called modulated
These are vocalizations issued more frequently by these individuals; and they are similar to squeaks and squawks. They are characterized by rapid changes in tone and rate of repetitions, and they use them during feeding and movement. Above all, to maintain contact with other members of the group, especially those outside the visual range.
It is important to point out, that each group of Orcas possess a different type of vocalization, which have been called dialects. They are unique and unrepeatable, besides of being also quite complex, thus only members of a group can identify them. Possibly, these dialects are learned from mother to child or by repetition.
Now, we invite you to watch this video to tottaly get aqcuainted with these vocalizations…
Alimentation Habits of Killer Whales:
These cetaceans are considered as excellent predators; since they feed on fish and other marine mammals. Killer whales living in captivity, are able to consume approximately 4% of their own body weight a day. This amount increases from birth until the age of twenty.
Killer Whales And Their Attack Techniques
The killer whales have attack techniques according to the region they inhabit, the hunted animal, and if it is carried out individually or in groups.
The Orcas coordinate their attacks with other whales, surrounding their prey and performing strong attacks and bites at various points of the body; until it yields because of the loss of blood.
In the southern areas of the Indian Ocean, the main prey is the emperor penguin. The killer whales dive into deep waters, and then they catch the penguins, when they are on the coast, which is the time when these animals are more clumsy. This technique is dangerous for the whale itself; since it is possible that they get stranded on the shore.
In the Scandinavian Peninsula, the herring is the main source of food for the killer whales. The strategy is to gather in groups and corral it around the boats, so that they come to the surface. Some of them float belly up emitting loud sounds, vocalizing or hitting the water with their tails, until the preys are numb and helpless.
Among the type of attacks according to the region; we find also the Orcas that pass through the Strait of Gibraltar, where the main prey is the red tuna. The strategy is to pursue them until they are exhausted. Likewise, the Orcas also learned to catch the tuna from fishing boats, while they are trapped within the nets; the orcas take advantage of the moment to devour many of them..
In Argentina, these cetaceans take advantage of the fact, that some wolves and sea elephants get stranded on the shore, to pounce over them and devour them.
The porpoises that live in Alaska, are the most coveted prey for this species, persecute them until they get tired; although both can swim at the same speed, the Orca is more resistant. So the prey ends exhausted and devoured.
In Antarctica the killer whales, wait for the seals to rest on small plates of ice in the middle of the sea, to then cause waves which throw them into the water.
Keep learning about their strategies, through this video;
Attacks on humans
There is few documentation about attacks, from killer whales to people in their natural habitat. Most have been produced by whales in captivity; so it is presumed to be a response to the abuse and stressful conditions they suffer. The first reported attack, dates from the beginning of the 20th century, when an Orca hit a piece of ice where some dogs and photographers were located. . It is presumed that barking attracted the attention of the whale.
In 1970, a surfer was bitten by one of these creatures while conducting maneuvers in California.
In 2.005, a young man who was swimming with diver suit in Alaska, was hit by a killer whale, it is believed that the suit, mistook it with one of their favorite prey.
However killer whales in captivity, become aggressive and have carried out violent scenes between them, against their caregivers or even against themselves. Their attacks sometimes have become deadly results.
The most recent episode occurred in the 2010 ,when the Orca Tilikum, hit its trainer to then drowning in pond ( in Seaworld, Orlando). It was reported later, that this was not his first attack on a human.
There are also reports of people who have seen a killer orca eating sharks, which opens the debate about…. if there was a battle between orca vs. shark who would win…. I think the answer is pretty obvious.
We have this illustrative video for you
Killer Whales: Main Threats
There are some conditions that can attempt against these creatures;
Death produced by accidents
These deaths occur mainly during fishing activities. The Orcas get trapped within the nets and other instruments used for these purposes.
In activities performed during tuna fishing, longliners have been a problem for the Orcas population.
Like most marine mammals, the killer whales are affected by secondary pollution. This means that the toxins and pollutants that are in the water, are absorbed by fish, seals and other animals that are the main source of food for these whales.
Oil spills in the waters, are another risk for this specie, as well as for the others animals they feed on. ( see article endangered whales)
Since killer whales employ echolocation for orienting purposes, they can be very sensitive to ship´s radars and military equipment. It is known , that sometimes they have even lost their sense of hearing, dying this way for getting in a state of anguish and shock.
There are many known illnesses that affect Orcas such as the listed below.
- Neoplasms, vascular and infectious diseases.
- Hodgkin’s disease, in which lesions were similar to those presented in humans.
- Skin lesions due to papilloma virus
- Infection by a gamma retrovirus involved in cases of immunodeficiency
There was a reported case, of an old Whale suffering severe arteriosclerosis of the coronary arteries. External parasites infections also occurs in this species, buy they are not very common.
The causes of death of captive specimens are listed following: pneumonia (25%), systemic Mycosis (22%), other bacterial infections (15.6%), abscess of mediastinum (9.4%) and deaths without diagnosis (28%).
Killer whales in captivity
In the 1960s killer whales were the main attraction in exhibitions at aquariums for recreational purposes; especially for their physical characteristics and intelligence to learn tricks and acrobatic maneuvers.
However, captivity is not the best stage for this species since, their life time is quite low under this condition.
The confinement compromises their mental and physical health, because they are subjected to pressures and punishments until they learn a new trick.
As for their physical development, there are evidences about alterations on their anatomy, such as the atrophy of their dorsal fin.
This can be caused by muscular atrophy, since the spaces where they are confined are small, and cannot be exercised as they would on the high seas.
It is believed that since they live in stable groups, when capturing a whale of this species. its matrilineal structure is broken affecting them some way.
Conservation of Killer Whales
This species was cataloged in the IUCN ( International Union for Conservation of Nature ) Red List in the year 2008, as subjects of insufficient data (English Data Deficient DD), justified decision given the possibility that there are two or more species, which would require to establish the specific risk for each of them. As long as the taxonomic classification is not clarified, it will remain classified as DD.1
In 2005, the government of the United States cataloged the community of Orcas residents of the south as threatened, under the Law for the Protection of Endangered Species. This community is composed of three groups that mainly inhabit the Georgia Straits, Haro and Puget in the state of Washington and British Columbia.
And despite the efforts made in protectionist conventions and programs, whales are the main source of hunting and fishing in some regions of the world. So, their population was initially estimated at two hundred animals, then reduced to only ninety in recent years.
Killer Whale: A wonderful species
Orcas are a sort of misunderstood creatures in the animal world. On the one hand, there is the ferocious image of a marine predator and on the other, that of a kind and intelligent creature.
In short, the term misused «killers» is not entirely true, since basically, these animals only hunt to survive; like most carnivores.
On the other hand, the Orcas do not belong to the family of whales, but the dolphins. Genetically, they are more linked to this species of cetaceans, despite its enormous size and its great weight.
If we compare them with humans beings, to determine who represents the most voracious species on earth, the Orcas have no comparison; since in such a case the humans would be much more murderous than these wild creatures.
In a global sense, the Orcas have a very varied diet; as explained above. The same way than humans, they are able to eat all kinds of food. The difference is that this species to subsist must use strategies to provide themselves with the quantities of nutrients required for their daily performance.
This qualification was used by whalers who watched the Orcas chase the whales and devour them; with the false belief that they used to murder other creatures of the same category. Which has already been explained that is not true.
Finally, killer whales aren´t whales neither killer. They are simply a wonderful carnivorous species that is positioned first in the marine diet, and that don´t affect man in any way.
In their relationship with humans, they are usually friendly, sociable and intelligent. If there is a harmful factor, it is the human element; in his desire to market this species, putting them in unnatural situations.
They are friendly and lovely……. try this video