Endangered. Designated endangered in Canada in 2001 and in the United States in 2005.
The Latin name is Orcinus orca. Common names are orca or killer whale, while other names include blackfish, grampus and killer. Most English-speaking scientists use the name killer whale, although orca is increasingly used, especially by the general public. The name killer whale originated from the Spanish whaler’s term “whale killer”, based on their observations of orcas hunting other types of whales. In ancient Roman mythology, the genus name, Orcinus, means "of the kingdom of the dead", or belonging to “Orcus", ruler of the dead. The species name in Latin, orca, literally means "the shape of a barrel or cask", likely due to the orca's body shape. This term is thought to be borrowed from the Greek word that was commonly used to refer to whales.
Orcas are the largest members of the dolphin family. Males are generally larger than females and adult males are distinguishable (sexually dimorphic) by the increased size of their dorsal fin at sexual maturity
(about 25 years).
Male Orcas usually grow to an average of 20-26 feet (6-8m) and weigh an average of 8,000-12,000 lb (3,600-5,400 kg).
Females grow to an average of 16-23 feet (5-7 m) and weigh between 3,000–6,000 lbs (1,300-2,700 kg).
Calves weigh about 400 lbs at birth (180 kg) and are between 7-8 feet long (2-3 m).
The largest male orca on record was 32 feet (9.8 m) and weighed over 20,000 lbs (9,000 kg), while the largest female was 28 feet (8.5 m) and weighed 15,000 lbs (6800 kg).
Killer whales are the largest members of the dolphin family.
Killer whales have a striking black coloring with grayish-white saddle patch and white belly. Much like their dolphin cousins, they have a conical-shaped head with small beak and 10-13 conical teeth on both the upper and lower jaw. They have paddle-shaped pectoral fins, and a distinct dorsal fin (curved in females and immature males; straight and up to about 5 feet in males). The males dorsal fin reaches full height at 15-25 years.
Like many other cetacean species, Orcas can be identified on an individual basis due to natural markings and differences in fin shape. Orcas have an obvious dorsal fin that varies in shape and size, often with distinctive nicks or scars. The saddle patch also varies from individual to individual in shape, size, color and scarring. In the case of the Southern Resident Orcas, individual identification allows us to maintain a precise census of the population, where every individual is known and accounted for. Link to ID Pages »
Orcas are in the suborder Odontoceti, or toothed whales, referred to as odontocites. Odondocites differ from other cetaceans (whales and dolphins) in that they have teeth instead of baleen, such as in humpbacks or grey whales. Orcas (killer whales) are one of 35 species in the oceanic dolphin family Delphinidae. Although they are referred to as whales, they are actually the largest members of the dolphin family and are physiologically similar to dolphins. Other similar species include: Pygmy killer whales, False killer whales and Pilot whales.
Although orcas (killer whales) tend to aggregate in cold water, they can be found in all the oceans of the world, from the Antarctic to the tropics. However, unlike other whales that follow predictable seasonal migration patterns, orcas tend to go wherever their food source is, making their movement patterns much less predictable. The distributions of some orcas are seasonally influenced by salmon or herring migrations. Other orca ecotypes (eg. Transients) will move in response to the location of their marine mammal prey, such as seals and sea lions.
The life cycle of orcas (killer whales) is similar to that of humans. Female orcas become mature around age 15. Currently among the Southern Residents, the youngest known mother is J37 at age 11. Mating and calving takes place year round. Gestation varies from 15 to 18 months, with the average birthing rate about once in every 5 years. A typical female will have an average of 3-5 calves within her lifetime. Females are reproductive until around age 40. Calf mortality is extremely high during the first year of life, when approximately 37–50% of all calves die. Calves will typically nurse until age two, but will begin to eat some solid food around age one.
The average lifespan of female orcas in the wild is 50 years, with several individuals living as long as 80–100 years. Currently J2 is the oldest known female of the Southern Resident Orcas, estimated to be 103 years old.
Male orcas become fully sexually mature at age 25. Between ages 12-15 their dorsal fin begins to grow taller and straighter, indicating the onset of sexual maturity. They typically don’t mate until after the age of 20.
Male orcas in the wild live 29 years on average, with a maximum of 50–60 years. J2’s relative, J1 (died in 2010) was estimated to be 59 at his death.
A captive orca's lifespan is typically much shorter, often by 25 years or more.
The saddle patch varies from individual to individual in shape, size, color and scarring.
J2 (Granny) is the oldest known Southern Resident Killer Whale and is estimated to be 103 years old, while J1 (Ruffles) was estimated to be 59 years old when he died in 2010.
J37 with calf J49.
In the North Pacific there are three recognized ecotypes of killer whales: Resident, Transient and Offshore.
Currently, there are ten recognized ecotypes of orcas (killer whales) in the world's oceans, five in each hemisphere. Of the ten ecotypes, some are distinct enough to be considered subspecies or even possibly separate species.
Resident: These are the most commonly sighted of the three orca populations in the coastal waters of the northeast Pacific. Residents' diets consist primarily of fish (salmon, cod, herring) and they typically consume between 100 to 300 lbs (45-135 kg) per day. The Residents live in complex and cohesive family groups called pods that are matriarchal in structure, where individuals rarely disperse from their natal matriline. Residents have a unique system of vocal dialects unlike any other marine mammal. Each clan has a specific dialect and each pod uses discrete calls. Pod-specific calls are thought to transfer information of maternal genealogy and may be important for group cohesion and inbreeding avoidance.
Residents differ significantly from Transient ecotypes in that they typically travel in large groups (10-80+ individuals). Resident ecotypes are morphologically identifiable by a rounded dorsal fin tip (in females and juveniles) that terminates in a sharp corner. Additionally, Residents, especially in the Pacific Northwest and southern British Columbia, often have open saddle patches, with black pigment coming into and breaking up the grayish-white saddle patch. Residents were given their name because they visit the same areas consistently, although their range generally expands seasonally.
There are three (3) main resident populations in the northeast Pacific. The Alaskan Resident population is the largest with an estimated 500+ individuals. The Northern Resident group that frequents the inland waters of Vancouver Island and Johnstone Strait has approximately 250 individuals. The smallest and most well known group is the Southern Resident clan (J, K and L pods) whose population is currently in decline.
The Southern Residents frequent the inland waters of Washington State and southern British Columbia. Their diet consists mostly of salmon with an obvious preference for Chinook (King/Spring). The Southern Residents are commonly seen from June-September. J pod is often observed in the region’s waters year-round. During the winter, members of K and L pods have been seen well off the west coast of Vancouver Island and as far south as Monterey, California. The Southern Residents are the main focus of the Orca Survey project.
Transient: Transients differ from Residents in that their diet consists almost exclusively of marine mammals, they generally travel in small groups, usually between two and six individuals, and have less stable family bonds. Transients also vocalize less and have a different dialect than other ecotypes. Physically, Transients are characterized by more triangular and pointed dorsal fins than those of Residents, and their saddle patch is generally solid. As their name implies, Transients have a wide range along the coast. Some individuals have been sighted in southern Alaska and California. Transients are increasingly referred to as Bigg's killer whale in honor of Michael Bigg. Although the range of Residents and Transients overlap, they generally avoid each other.
Offshore: This third population of orcas found in the northeast Pacific was discovered in 1988. As their name suggests, they travel far from shore and are rarely seen. They feed primarily on schooling fish; however, evidence suggests they may also eat marine mammals and sharks. Other than a handful of sightings within the inland waters of Washington State and British Columbia, they have mostly been encountered off the west coast of Vancouver Island and near the Haida Gwaii (formerly Queen Charlotte Islands). Offshores are typically seen in groups of 20–75, with occasional sightings of larger groups of up to 200. Compared to Residents and Transients, Offshores are generally smaller and have a more rounded dorsal fin tip often with many nicks and scratches. They have a unique dialect and although genetically distinct, they are more closely related to Residents. In contrast with north Pacific Residents and Transients, little in known about Offshores.
Type 1 seems to have a varied diet consisting of both fish and marine mammals. Filed observations suggest that different groups may specialize on different prey. Type 1 is smaller and shows significant tooth wear. The Resident ecotype groups seen feeding on herring and mackerel off the coast of Norway, Scotland and Iceland are of this type.
Type 2 is larger than Type 1 and in contrast shows almost no tooth wear. They seem to more closely resemble the Transients we have in the Pacific, as they appear to eat exclusively other marine mammals.
North Atlantic killer whales.
Photograph courtesy of North Atlantic Killer Whale Project
Type A looks like a typical Transient-ecotype orca with a medium-sized eyepatch oriented parallel with the body axis. The size range of this ecotype is unknown, however based on field observations there appears to be a lot of variation among groups, with adult males ranging from approximately 23-30 feet (7-9m). Type A orcas are found around the entire Antarctic continent. They live more in open water, outside of the pack ice, and seem to eat mostly Antarctic Minke whales.
Type B comes in two sub-ecotypes: large and small. The large type B are smaller than type A. They are more gray than black, with a dark gray dorsal cape. They have a comparatively large white eye patch oriented parallel to the body. They are often covered in diatoms giving any white pigment a yellow or brownish tint. They are referred to as Pack Ice killer whales because they are regularly seen foraging in groups around the edge of the pack ice. They hunt mostly seals (preferably Weddell seals) in cooperative groups, washing them off the ice floes into the water. The smaller type B’s are referred to as Gerlache killer whales because of their abundance around Gerlache Strait off the western Antarctic Peninsula. They are smaller than the Pack Ice Killer Whales, with a large eyepatch that is slightly slanted downward. They travel in large groups in the open water away from the pack ice. They have been observed eating mostly penguins, often only taking the breast meat and leaving the rest of the carcass.
Type C is referred to as the Ross Sea killer whale. Like the type B’s they are gray with a darker gray cape and frequently covered in diatomes. Unlike other ecotypes, they have a narrow eyepatch that is tilted forward about 45 degrees. They are the smallest type of orcas known, measuring about 20 feet (6m). This type is found only in the east Antarctic, living deep in the pack ice. The only prey they have been observed eating is an Antarctic toothfish.
Type D are known as subantarctic orcas. It is easily distinguished from other ecotypes because of the very tiny eyepatch and more bulbous mellon. They have been sighted all around the subantarctic. It was first identified in photographs of a 1955 mass stranding in New Zealand. Very little is known of Type D’s diet, except that it has been photographed around longline vessels fishing for Chilean seabass.
Type C Antarctic killer whale.
Photograph by Robert Pitman, NOAA
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