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The orc or épaulard ( Orcinus orca ) is a Marine mammal sub-order of the Cétacé S with teeth (Odontocète S). It easily recognizable with its is delivered black and white and to the size of its dorsal fin which can reach 2 m height in the males. It counts among the Mammifère S the most widespread sailors on the Ground. Although it acts of a Prédateur and in spite of its English nickname of killer whale (tueuse whale), the orc in freedom does not attack the Homme.

Etymology

Its Latin name d´ Orcinus orca has several significances of which most known are: “ that which brings death” or “ demon of the hell ”. In fact the Romain S gave this direction to the Latin name of the orc. Today, “orca” would mean “ animal very wild, with the body in the shape of barrel ” and “Orcinus” would mean “ orc ”. However, other scientists give another direction to this Latin name. Moreover, the Latin name of the orc traversed several stages before the term of Orcinus orca . In the first description of Linné in 1758, it named it “ Delphinus orca ”. In 1860, Fitzinger employed the first term Orcinus . Van Beneden and Gervais employed another denomination: Orca gladiator . Then, the Latin name of the orc undergoes several successive revisions of the systematic one! It ends up being found in the kind Grampus , under the name of Grampus rectipinna for the specimens provided with more developed ailerons. Today, the Orc ( Orcinus orca ) is regarded as the only species of the kind Orcinus .

The " term; orque" is a female substantive. The two kinds however are granted; one can say to write " un" orc and " une" orc; but a " épaulard" remain him male.

Behavior

Frightening hunter, its food primarily consists of Poisson S and others Mammifère S sailors (sea lions, Otarie S, Phoque S, Marsouin S, Baleine S). The proportions of these preys in the food mode as well as the techniques of hunting employed vary according to the populations. The orcs drive out the marine mammals such as the seals and sea lions while grinding very close to the beaches, and by using the technique of stranding on the shore.

The orcs are opportunist, it thus happens that when they cross a Baleine and its small, they are put in hunting. Their technique consists in trying to separate the mother from small while passing above them, and while trying to put itself between them. Most of the time it is the dominant orc, largest, which intercalates itself between the whale-calf and its mother. In their turn, the other orcs direct the baby in the depths for the walnut tree. The whale gives up sometimes its small if it is exhausted too much by defense vis-a-vis their predatory. The orcs eat only the language and the jaw lower of the whales. Shark S and others Poisson S are given the responsability to devour the remainder of the corpse.

The orcs belong to the same family as the Dauphin S and, just like the latter, their raising is relatively easy. Their spectacular imposing size, their beauty and their jumps make of them the attractions very appreciated by the visitors of the Delphinarium S.

3 well defined types of orcs are distinguished:

  • the wandering orcs are constantly in displacement and quiet. They are sometimes solitary, or in small groups from 2 to 7 individuals. Their sounds get along only at the time of a meal. These are the orcs which attack with the Requin S and the marine mammals of big size. They have a pointed and right aileron.
  • the orcs resident are always in the same zone. They live in groups of 5 to 50 individuals directed by the senior of the females. They nourish Saumon S and other fish, more rarely of small marine mammals.
  • the orcs offshore oil rig are mainly Ichtyophage S and live in troop from 30 to 60 individuals. One meets these orcs in Norway, where they are famous to drive out the Hareng, and in British Columbia.

Physical characteristics

Morphology

The orcs are Odontocète S, or whales with teeth.

The orcs have a characteristic appearance with a black back, a white belly and a white spot behind and above the eye. The body powerful and is surmounted by a large dorsal aileron with a spot dark gray (sometimes decorated of mauve) in the shape of saddle right behind. The males can measure up to 9,5 m length (the largest specimen never considering measured 9,74 m) and weigh more than 9 tons (the heaviest specimen weighed 11 tons); the females are smaller, reaching up to 8,5 m for a mass of approximately 5 tons (the maximum known for a female is of 7,5 tons). With the birth, the newborn weighs approximately 150 to 220 kilos and measurement between 2 and 2,70 m length. With the difference of the majority of the dolphins, the caudal Nageoire of an orc is broad and round (it can measure more than 2,40 m of scale). Being able to measure more than 2 meters, the dorsal aileron of the male is larger than that of the female (approximately 90 cm). It has a form of lengthened Isosceles triangle while the dorsal aileron of the female is shorter and with the form of a false.

However, the scientists noted that there were orcs of dwarf form in the Antarctic. Certain specialists want to regard them as a species with share by naming them Orca glacialis or Orca nanus . But of others refuse to regard it as a species different of Orcinus orca .

Average and maximum measurements in the orcs of common form

  • average Length of the males: 6,70 to 8,20 m

  • average Length of the females: 5,50 to 7,30 m
  • average Weight of the males: 5 to 7 tons
  • average Weight of the females: 2,50 to 4 tons
  • maximum Length of the males: 9,80 m
  • maximum Length of the females: 8,40 m
  • maximum Weight of the males: 12 tons
  • maximum Weight of the females: 8 tons

Average and maximum measurements in the orcs of dwarf form

  • average Length of the males: 6,50 to 7 m

  • average Length of the females: 5 to 6 m
  • average Weight of the males: 5 to 6,50 tons
  • average Weight of the females: 2,50 to 3 tons
  • maximum Length of the males: 7,50 m
  • maximum Length of the females: 6,50 m
  • maximum Weight of the males: 8, tons
  • maximum Weight of the females: 4 tons

The scientists identify the individuals thanks to the notches, blows and scratches on their ailerons like thanks to the shape of the aileron.

The male orc has a characteristic silhouette which cannot be confused with that of another species of marine animal. In moderated water, the females and the youthful ones, if they are observed of a certain distance, can be taken for representatives of species like the False-épaulard or the Dauphin of Risso.

Life cycle

The majority of the data on the life cycle of the orcs come from campaigns from observation from long life relating to gregarious populations living along the coasts from Colombia-British and the State from Washington as well as studies undertaken on orcs in captivity. Taking into account the meticulousness of the undertaken studies and strongly structured nature of the groups of orcs of these populations, the data which one lays out can be regarded as right and detailed; however the groups of orcs transhumants and those alive in others Océan S can have slightly different characteristics. The females become adult at approximately 15 years. Starting from this age, they have periods of fertility separated by 3 to 16 month. The duration of the period of Gestation is variable, from fifteen to eighteen months. The mothers give rise to only one newborn, approximately once every five years. In the gregarious groups of orcs studied, the births spread out throughout the year, the peak of birth being in winter. The mortality of the new-born babies is very high; according to a study, it seems that about half die before to have reached the six months age. The new-born babies are nursed during 2 years, but start to nourish themselves as from the twelve months age.

The females reproduce until the 40 years age; they thus raise on average 5 new-born babies. The female orcs live on average until the fifty years age, but some can live up to 80 even 90 years in exceptional cases. The males sexually become active at the 15 years age, and live approximately 30 years on average, 50 years in exceptional cases.

The orc in figures

  • Maximum speed: 55km/h (the scientists estimate all the same that some can reach the speed of 65 km/h).

  • maximum Age: nearly 90 years
  • Middle Age: 35-50ans
  • sexual Maturity: 6-10 years for the males and 12-16 years for the females.
  • Weight with the birth: 180kg
  • Size with the birth: 2-2.70 m

Food

The orc nourishes fish, of birds of sea, Manchot S, Phoque S, , , sea lions Dauphin S Marsouin S and also others Cétacé S, the exact content of their food depending on their habitat. it is a question of the one of the rare Cetacea to be attacked other marine mammals (the pseudorque would attack it also small marine mammals). Scientists even recently observed a band of orcs which attacked ten Cachalot S! All the cachalots were wounded (certain seriously) and at least was killed.

The orcs live, move and drive out in group of 3 to 40 individuals in the majority of the oceans. The range of the techniques of hunting developed by the orc is vast, and depends at the same time on the prey and the environment. Thus, in the Southern hemisphere, hunting for the Pinnipède S is done it sometimes by voluntary stranding on the beach. The orcs use the echolocation, a system of natural Sonar, except in the case of the tracking of the other Cetacea. Huntings can proceed on the open sea or close to the coasts, in which case the prey is folded back towards the ground until more being able to escape its predatory. When it is about large Cetacea, all the members of the group take part, the ones immobilizing the animal by the tail while the others strike it on all sides.

The épaulard never attacks the man, in spite of certain rumors.

Particular case: Although the White shark and the orc are unaware of themselves when they cross, it is not rare that orcs attack white sharks. Thus, in bay of Monterey, in California, a female orc of approximately 6 meters and name of number " CA2" was observed on several occasions assailing of the white sharks. The first observation, going back to October 1997, it is when CA2 attacked and killed an white shark of 3,50 meters to protect its small. CA2 had caught the shark in its mouth, while leaping in the airs. In spite of the extremely solid skin (more solid than of leather), the shark had been put in part by the orc. The second observation, it is when CA2 attacked a larger white shark (it was to make 4,50 maximum) and killed it to seek its preferred met: the liver of shark.

When the orc becomes prey: the reverse can also occur. Thus, in Australia, a large white shark from approximately 5 to 6 meters, killed an orc 5 meters length subadulte, by breaking it (an attack by lower part). The jaws of the white shark make considerable damage, and the orc died quickly. However, it was about a sick and weakened orc, isolated from its group. The white shark benefitted from this occasion to nourish itself with its hunger.

Where to observe the orcs?

Orc with the cinema

One or more orcs are main characters in films:

See too

External bonds

  • Site on the various orcs and their mode of reproduction avoiding consanguinity.

  • Site of an observatory of the English orcs, including/understanding many small films
  • orcs of Alaska (North GULF Oceanic Society)

  • Article in French of a Canadian governmental site

  • Biology of the Orcs
  • Card and vidéos of orc
  • Encyclopedia of the Cetacea

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