Killer whale - Wikipedia. The killer whale or orca (Orcinus orca) is a toothed whale belonging to the oceanic dolphin family, of which it is the largest member. Killer whales have a diverse diet, although individual populations often specialize in particular types of prey. Some feed exclusively on fish, while others hunt marine mammals such as seals and dolphins. They have been known to attack baleen whale calves, and even adult whales. Killer whales are apex predators, as there is no animal that preys on them. 2007 Amazon Minke Whale Diet PlanktonKiller whales are considered a cosmopolitan species, and can be found in each of the world's oceans in a variety of marine environments, from Arctic and Antarctic regions to tropical seas. Killer whales are highly social; some populations are composed of matrilineal family groups (pods) which are the most stable of any animal species. Their sophisticated hunting techniques and vocal behaviours, which are often specific to a particular group and passed across generations, have been described as manifestations of animal culture. Some local populations are considered threatened or endangered due to prey depletion, habitat loss, pollution (by PCBs), capture for marine mammal parks, and conflicts with human fisheries. In late 2. 00. 5, the Southern Resident Killer Whales, the population that inhabits British Columbia and Washington state waters, were placed on the U. S. Endangered Species list. Wild killer whales are not considered a threat to humans, but there have been cases of captive orcas killing or injuring their handlers at marine theme parks. The killer whale lineage probably branched off shortly thereafter. Although it has morphological similarities with the pygmy killer whale, the false killer whale and the pilot whales, a study of cytochrome b gene sequences by Richard Le. Duc indicated that its closest extant relatives are the snubfin dolphins of the genus Orcaella. ![]() Killer whale advocates point out it has a long heritage. Indeed, the genus name Orcinus means . The IUCN reported in 2. Residents' diets consist primarily of fish. They visit the same areas consistently. British Columbia and Washington resident populations are amongst the most intensively studied marine mammals anywhere in the world. Researchers have identified and named over 3. Transient: The diets of these whales consist almost exclusively of marine mammals. Renan and I halt in a small rock recess overlooking the north face of the mountain. Through blowing spindrift we can see Cory traversing another expanse of snow. Humpback whales are rorquals (Balaenopteridae, a family that includes the blue, fin, Bryde's, sei and minke whales). The rorquals are believed to have diverged from. The killer whale or orca (Orcinus orca) is a toothed whale belonging to the oceanic dolphin family, of which it is the largest member. Killer whales have a diverse. Celebrating 25 Years of Award-winning Arctic and East Coast Voyages to Nunavut, Greenland, Labrador and Newfoundland. See world news photos and videos at ABCNews.com. The gray or white area around the dorsal fin, known as the . However, the saddle patches of transients are solid and uniformly gray. Transients roam widely along the coast; some individuals have been sighted in both southern Alaska and California. Transients are also referred to as Bigg's killer whale in honor of cetologist. Michael Bigg. The term has become increasingly common and may eventually replace the transient label. As their name suggests, they travel far from shore and feed primarily on schooling fish. However, because they have large, scarred and nicked dorsal fins resembling those of mammal- hunting transients, it may be that they also eat mammals and sharks. 2007 Amazon Minke Whale DietsOffshores typically congregate in groups of 2. Offshores appear to be smaller than the others, and females are characterized by dorsal fin tips that are continuously rounded. Transients and residents live in the same areas, but avoid each other. Researchers later discovered transients are not born into resident pods. The evolutionary split between the two groups is believed to have begun two million years ago. Genetic data indicate the types have not interbred for up to 1. Two dwarf species, named Orcinus nanus and Orcinus glacialis, were described during the 1. Soviet researchers, but most cetacean researchers are skeptical about their status, and linking these directly to the types described below is difficult. It has a large white eye patch. Fat Loss via Better Science and Simplicity. It is possible to lose 20 lbs. Most of the dark parts of its body are medium gray instead of black, although it has a dark gray patch called a . The white areas are stained slightly yellow. It feeds mostly on seals. Its eye patch is distinctively slanted forwards, rather than parallel to the body axis. Like type B, it is primarily white and medium gray, with a dark gray dorsal cape and yellow- tinged patches. Its only observed prey is the Antarctic cod. The first video record of this type in life happened between the Kerguelen and Crozet Islands in 2. And although nothing is known about the type D diet, it is suspected to include fish because groups have been photographed around longline vessels, where they reportedly prey on Patagonian toothfish (Dissostichus eleginoides). Of three orca ecotypes in the Antarctic, one preys on minke whales, the second on seals and penguins and the third on fish. Another ecotype lives in the eastern North Atlantic, while the three Northeast Pacific ecotypes are labeled the transient, resident and offshore populations, as discussed above. The research supported a proposal to reclassify the Antarctic seal- and fish- eating populations and the North Pacific transients as a distinct species, leaving the remaining ecotypes as subspecies. The first split in the orca population, between the North Pacific transients and the rest, occurred an estimated 7. Such a designation would mean that each new species becomes subject to separate conservation assessments. Calves are born with a yellowish or orange tint, which fades to white. It has a heavy and robust body. Antarctic killer whales may have pale grey to nearly white backs. Adult killer whales are very distinctive and are not usually confused with any other sea creature. When seen from a distance, juveniles can be confused with other cetacean species, such as the false killer whale or Risso's dolphin. The front teeth are inclined slightly forward and outward, thus allowing the killer whale to withstand powerful jerking movements from its prey while the middle and back teeth hold it firmly in place. Killer whales are the largest extant members of the dolphin family. Males typically range from 6 to 8 metres (2. Females are smaller, generally ranging from 5 to 7 m (1. The largest male killer whale on record was 9. Males have significantly larger pectoral fins than females. At about 1. 8 m (5. Variations such as nicks, scratches, and tears on the dorsal fin and the pattern of white or grey in the saddle patch are unique. Published directories contain identifying photographs and names for hundreds of North Pacific animals. Photographic identification has enabled the local population of killer whales to be counted each year rather than estimated, and has enabled great insight into lifecycles and social structures. Occasionally a killer whale is white; they have been spotted in the northern Bering Sea and around St. Lawrence Island, and near the Russian coast. Burdin and Erich Hoyt, filmed an adult male nicknamed Iceberg . They have exceptionally sophisticated echolocation abilities, detecting the location and characteristics of prey and other objects in their environments by emitting clicks and listening for echoes, as do other members of the dolphin family. The mean body temperature of the orca is 3. Females can often breed until age 4. An exception is Granny (J2), who was the oldest known orca, estimated to have been 1. Gestation varies from 1. In resident pods, births occur at any time of year, although winter is the most common. Mortality is extremely high during the first seven months of life, when 3. According to observations in several regions, all male and female pod members participate in the care of the young. Males sexually mature at the age of 1. Wild males live around 2. One male, known as Old Tom, was reportedly spotted every winter between the 1. New South Wales, Australia. This would have made him up to 9. Examination of his teeth indicated he died around age 3. Due to their enormous range, numbers, and density, distributional estimates are difficult to compare. High densities have also been reported but not quantified in the western North Pacific around the Sea of Japan (in very limited areas and more abundant on the side of Primorsky Krai. They are reported as seasonally common in the Canadian Arctic, including Baffin Bay between Greenland and Nunavut, and around Tasmania and Macquarie Island. They have been sighted, for example, in the Mediterranean, the Arabian Sea, the Gulf of Mexico and the Indian Ocean around the Seychelles. Large concentrations are known to occur north of the Northern Mariana Islands. Recorded sightings have been made from almost the entire shoreline; from Bohai and the Yellow Sea in the north to the Zhoushan Islands in the east. However, killer whales are merely seasonal visitors to Arctic waters, and do not approach the pack ice in the summer. With the rapid Arctic sea ice decline in the Hudson Strait, their range now extends deep into the northwest Atlantic. They have been documented 1. Columbia River in the United States. Each summer, the same individuals appear off the coasts of British Columbia and Washington. Despite decades of research, where these animals go for the rest of the year remains unknown. Transient pods have been sighted from southern Alaska to central California. Population. Worldwide population estimates are uncertain, but recent consensus suggests an absolute minimum of 5. Japan's Fisheries Agency estimated 2,3. Japan. They are sometimes called the wolves of the sea, because they hunt in groups like wolf packs. However, different populations or species tend to specialize and some can have a dramatic impact on certain prey species. This specialization in diet and hunting is another reason to suggest that the orca is in fact several species, as discussed above. Fish. Resident (fish- eating) killer whales: The curved dorsal fins are typical of resident females. Fish- eating killer whales prey on around 3. Some populations in the Norwegian and Greenland sea specialize in herring and follow that fish's autumnal migration to the Norwegian coast. Salmon account for 9. Pacific residents' diet. About 6. 5% of them are large, fatty Chinook. Technology and Science News - ABC News.
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