Here is where you will find all you need to know on Orcinus orca. Also known as the Killer Whale, Orca, the Orca Whale, Blackfish, Grampus, Sea Wolf, Kosatka/Kasatka (Russian), Epaulard (French), Skaana (Haida), Queet (Tlingit), Sakamata/Shachi (Japanese), Spaekhogger (Norway), Spaekhugger (Denmark), or Hahyrna (Icelandic).
Kingdom: Animalia
Phylum: Chordata
Sub-Phylum: Vertebrata
Class: Mammalia (mammals)
Order: Cetacean (whales, dolphins, porpoises)
Sub-Order: Odontoceti (toothed cetaceans)
Family: Delphinidae (dolphins and porpoises)
Genus: Orcinus
Species: orca
Size Statistics
Male killer whales are the record holders for length and weight. They can live to be around 50 years old, but 30 years is the average lifespan. Their dorsal fins stand 6 ft. tall, taller than the average man. Their average length is between 22 and 27 feet. They can weigh up to 12,000 pounds or more. Their pectorals can measure over 4 to 5 feet across. A young male before puberty can easily be confused for a female. The males go through a maturing phase in which they gain weight, their flukes curl under, their pectorals grow broad and large, and their dorsal fins sprout upwards. The largest male on record was an astonishing 32 feet long and weighed 21,000 lbs. Some of the largest captive males are Tilikum, Kandu VII and Kim II.
Female orcas are somewhat smaller than males but nonetheless are considered to be rather large creatures. They live much longer than the males, up to 80 years in some cases. But their average lifespan is 50 years, the maximum of a male. 17 to 24 feet is the expected length and 3,000 to 8,000 pounds is the average weight. A female orca's dorsal fin is much shorter and curved than a male orca's: only 2 feet tall. The largest female on record was an 28 feet long and weighed 15,000 lbs; that's even larger than the average male orca. In captivity, the largest female is Corky II of Sea World California.Habitat And Diet
Habitat: Orcas can be found in every ocean on Earth. Their numbers are very numerous in the Arctic, Antarctic, the North Atlantic and the Pacific Northwest in particular. The exact worldwide population is unknown but calculations in certian areas have been documented (ex. the Antarctic population is about 180,000 individuals). They can be found in open sea or coastal waters. It is considered rare to observe them in tropical climates, though sightings have occured in parts of the Gulf of Mexico.
Diet: Most orcas eat fish and squid rather than other marine mammals. Transients of the NW and South America prey on primarily seals, birds, sharks, dolphins, and baleen whales. Early observation of this group is the reason orcas received the title of "killer whale". In the Antarctic, orcas have been observed tipping over small iceburgs to knock seals or penguins into the water. They have conical (or peg-like) teeth, good for only gripping their prey. They cannot chew their food. Using the muscles in their necks and upper body, they shred larger prey to bits. Smaller prey is swallowed whole. Based on studies featuring captive orcas, these whales are not known to have taste for sure. But some do have preferences for certian species of fish. A killer whale eats 3% to 4% of its body weight in food each day. The name Sea Wolf comes from the fact orcas work together to catch food, like wolves and lions.
Taxonomy And Evolution
The killer whale is the sole species in the genus known as Orcinus. Like the genus Physeter (relating to Sperm Whales), Orcinus is a category with a single, abundant species with no immediate relatives from a cladistic* point of view, thus palaeontologists believe that orcas are prime candidates to have an anagenetic evolutionary history — that is the evolution of ancestral to descendant species without true splitting of the lineage. If true, this would make the orca one of the oldest dolphin species alive today. However, it is unlikely to be as old the family itself, which is known to date back at least five million years.
*cladistic - A system of classification based on the phylogenetic relationships and evolutionary history of groups of organisms.
Other Facts:
-Orcas have glands at the inner corners of their eyes that secrete oily, jelly like mucus that keeps their eyes moist, washes out debris, and protects the outer cortex from the salt of the water.
-The white spots on either side of the orca's head are called "eyepatches" and can be used to identify individuals. They also serve as a trick. Should any daring dolphin or seal try to aim for the eyes they would be confused by the white patches. The eyes are in fact just below the front end of each patch.
-Eye color differs in orcas as it does in humans.
-Orcas have taste buds and some have preferences for certian types of fish.
-They have little to no sense of smell at all.
-In dark waters one orca would probably rely more on echolocation, a sense that is very similiar to sonar used in the Navy, than his or her eyesight.
-Orcas can dive 200 feet straight down.
-Transient orcas that are found off the Patagonian coast are known world-wide for virtually throwing themselves ashore to grab sea lion pups.
-Orcas have no gag reflex, meaning they cannot dislodge food or objects caught in their throats. They can regurgitate food only after it has made its way down to the stomach.
-It is not known for certian why orcas strand. Sick or dying animals have been documented coming ashore.
-Orcas are actually the largest members of the dolphin family (which consists of a total 35 species).
-The species False Killer Whale and orca are quite seperate from one another.
Types Of Orcas
Residents: Residents are the most numerous orca "sub-species" in Northwestern waters. Their dorsal fins are more curved at the tip. They eat mostly fish and squid. Groups of Residents are the largest and can have up to 50 animals, typically led by an elderly female and her family. The name "Resident" refers to these orcas' tendancies to stay around one general location. They are the most vocal group of orcas.
Transients: Transients are the real "killer" whales. Their diet consists of almost anything bathed in saltwater: squid, seals, penguins, sea lions, birds, sharks, otters, other dolphins, porpoises and even large baleen whales that may be 3 times larger than themselves. The dorsal of a male Transient is very rigid and pointed, with no curve at the tip. Transient orcas are usually found in small groups or going it alone. They are usually found further away from shore and tend to be silent. The only time you will hear them vocalizing is after a successful kill.
Offshores: The most recently discovered group is that of the Offshore. Virtually nothing is known about them. Their diet is similiar to a Resident's: fish and squid. Offshores are found the furthest out of all the orcas. Their dorsal structure is unknown but is probably related to Residents.
Wild Behaviors
Wild orcas exhibit many behaviors. Some are fairly well known to most of society but there are some that some probably don't even know about.
Breach. An orca leaps clean out of the water to land on its front, side, or back. The most spectacular behavior an orca can perform.
Porpoising. An orca traveling at high speed lances out of the water, keeping a low profile. Orcas are sometimes witnessed doing this in the wake of large ships or boats. This is referred to as wake-riding.
Spyhop. An orca thrusts its upper body or head completely out of the water. Orcas use this behavior to better observe their surroundings above the surface.
Lobtailing. An orca wrenches its tail up after a dive and lets the flukes slap against the water's surface. This behavior is often used to stun fish when hunting and can be exhibited underwater as well.
Pectoral slapping. An orca turns onto its side, raises a pectoral (flipper) and slaps it against the water's surface.
*Female killer whales mature around the age of 14 while the males mature at 10 to 13. There have been cases of females having calves in captivity at ages under 10. Young males can be seen engaging in sexual plays with other males even before maturity. A female can have a calf every three years. Which means she can have from 4 to 6 children throughout her lifetime (over a 25 year reproduction period). An orca's gestation cycle (pregnancy) lasts for a year and a half (18 months). The average length is that of 17 though calves in captivity have been delievered as early as 11 (see: Splash). Calves can be delievered tail or head first. Tail first is more common and much more safe. If it is a tail first birth, the soft flukes will have a chance to stiffen in the cold water before the calf is fully free of its mother.
*At birth, an orca calf can be between 6 to 8 feet long and weigh 350 lbs. The dorsal fin and flukes remain fairly soft at first but harden over the course of the next few days. Calves can be an orange or a creamy yellow rather than pure white. This coloration fades as they age. They begin to nurse within hours of being born, from one of the two mammary slits on either side of the mother's genital opening. They continue to feed this way for up to a year. Like human babies, newborn orca calves cry and cannot "speak" in the same sense as their elders. Only when they are about 2 months old do they start to learn how to "talk" to their mother or podmates. Most calves stay with their mothers all their lives, but male Transients are known to go off on their own after they are done growing up.
*Young orcas tend to stick close to their mothers or siblings while traveling. A calf would swim next to or below its mother's tail, pulled along by the "slipstream" - also known as the hydrodynamic wake that develops from the mother's movements. This allows the young to keep with the rest of the group, while saving energy at the same time. At birth, they don't even have teeth. The teeth erupt at 3 to 4 months after birth. By the time they reach one year of age, orca calves are somewhere between 9 and 11 feet long and have nearly tripled in weight.
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