Killer whale (Orcinus orca) : : NOAA Fisheries. Status. ESA Endangered - Southern Resident killer whales (J, K, and L pods)MMPA Depleted - AT1 Transients. MMPA - all populations. CITES Appendix II - all populations. Species Description. Killer Whales In CaptivityWeight: males can weigh up to 2. Length: males can reach 3. Appearance: black on top with white undersides and white patches near their eyes; highly variable gray or white saddle behind the dorsal fin; these markings are unique across individuals and populations. Killer whales are top predators. Feeding behavior is hard to study in living. The killer whale is the only. At feeding time killer whales reveal not so much their. Baleen Whales Diet & Eating Habits Food Preferences And Resources. Observers have seen several humpback whales lunge-feeding up through a "bubble net". ![]() Lifespan: up to 5. Diet: varies (diet is often geographic or population specific), can include fish, marine mammals, sharks, and sea birds. Same Species, Different Habits by Xenia Shih. Orcas, or killer whales. The differences in pod sizes are probably due to differences in feeding habits. By studying the feeding behavior of killer whales in. For example, killer whales that feed on. A resident killer whale feeding on salmon. The diet of northern resident killer whales. ![]() Behavior: highly social animals, living within matriarchal societies; rely on underwater sound for orientation, feeding, and communication; produce whistles and pulsed calls, used for communication and maintaining group cohesion. Killer whales most widely distributed marine mammals, found in all parts of the oceans; most abundant in colder waters, including Antarctica, the North Atlantic and Pacific Oceans. They also occur, though at lower densities, in tropical, subtropical, and offshore waters. Killer whales are generally considered monotypic (belonging to one species). However, genetic studies and morphological evidence have led many cetacean biologists to now consider the existence of multiple species or subspecies of killer whales worldwide. The species shows considerable size . Adult males develop larger pectoral flippers, dorsal fins, tail flukes, and girths than females. Female killer whales reach sexual maturity when they grow to about 1. The gestation period for killer whales varies from 1. Birth may take place in any month- -there is no distinct calving season. Calves are nursed for at least 1 year, and may be weaned between 1- 2 years old. The birth rate for killer whales is not well understood, but, in some populations, is estimated as every 5 years for an average period of 2. Killer whales are highly social animals that occur primarily in relatively stable social groups that often range in size from 2 to 1. Larger groups (rarely as large as several hundred individuals) occasionally form, but are usually considered temporary groupings of smaller social units that probably congregate for seasonal concentrations of prey, social interaction, or mating. Why Killer Whales Are EndangeredSingle whales, usually adult males, also occur in Bigg's killer whale populations (as discussed below). Differences in spatial distribution, abundance, behavior, and availability of food resources probably account for much of the variation in group size among killer whale populations. Populations and Social Organization. Scientific studies have revealed many different populations- -or even potentially different species or subspecies- -of killer whales worldwide. These different populations of killer whales may exhibit different dietary needs, behavior patterns, social structures, and habitat preferences. Therefore, interbreeding is not expected to occur between different populations, in spite of the overlap between home ranges. The most well- studied killer whale populations occur in the eastern North Pacific Ocean. Three distinct forms, or ecotypes, of killer whales are recognized: 2. Resident. Transient, or Bigg's. Offshore. The three types differ in morphology, ecology, behavior, and genetics. ![]() ![]() A recent genetic study. Bigg’s killer whales. All three types of killer whales share at least part of a home range, yet they are not known to intermix with one another. The resident and transient types both have multiple populations within their range. Resident Killer Whales are noticeably different from both transient and offshore forms. The dorsal fin is rounded at the tip and curved and tapering, or . Resident whales have a variety of saddle patch pigmentations with five different patterns recognized. ![]() They've been sighted from California to Russia. Resident whales primarily eat fish. Resident killer whales in the U. S. North Pacific consist of the following populations: Southern residents. Northern residents. Southern Alaska residents. Western Alaska North Pacific residents. Resident type killer whales occur in large social groups called . The pods represent collections of matrilines, their fundamental social unit. Southern Resident killer whales are the only known resident population to occur in the U. S. Southern residents are comprised of three pods: J, K, and L pods. The Southern Residentsare considered one . ![]() Beginning in the late 1. Southern Resident numbers. The population fell an estimated 3. By 2. 00. 3, the population increased to 8. Due to its small population size, we listed this segment of the population as endangered under the Endangered Species Act (ESA) in 2. Their range during the spring, summer, and fall includes the inland waterways of Washington state and the transboundary waters between the United States and Canada. Relatively little is known about the winter movements and range of the Southern Resident stock. However, in recent years, they have been regularly spotted as far south as central California during the winter months and as far north as Southeast Alaska, through our Northwest Fisheries Science Center's satellite tagging work. More information on Southern Residents can be found on our West Coast Region's website. Bigg's (Transient) Killer Whales occur throughout the eastern North Pacific, and have primarily been studied in coastal waters. Their geographic range overlaps that of the resident and offshore killer whales. The dorsal fin of transient whales tends to be straighter at the tip than those of resident and offshore whales. Saddle patch pigmentation of transient killer whales is restricted to two patterns, and the large areas of black color don't mix into the white of the saddle patch that is seen in resident and offshore types. Transient type whales are often found in long- term stable social units of less than 1. Transient killer whales feed nearly exclusively on other marine mammals. AT1 Transients were one of the most frequently encountered groups and, in the 1. Prince William Sound. The AT1 group was made up of at least 2. Exxon Valdez oil spill. Several confirmed deaths of AT1 killer whales have been recorded since the 1. In June 2. 00. 4, we designated the AT1 group of transient killer whales as a depleted stock under the MMPA. Scientists estimate there are only 7 killer whales remaining in this group. Offshore Killer Whales are similar to resident whales, but can be distinguished generally. But, they also visit coastal waters and occasionally enter protected inshore waters. Animals typically congregate in groups of 2. They are presumed to feed primarily on fish, though they have been documented feeding on sharks. Genetic analyses indicate that offshore killer whales are reproductively isolated from other forms of killer whales. Offshore killer whales are among the least observed and understood of all killer whale populations. Diet. The diet of killer whales is often geographic or population specific: Resident killer whale populations in the eastern North Pacific mainly feed on: salmonids, showing a strong preference for Chinook salmon. Bigg's (Transient) killer whale populations in the eastern North Pacific feed on marine mammals, such as (in order of frequency of observation): harbor seals. Dall's porpoisesharbor porpoise. California sea lionsgray whale calves. Steller sea lionselephant sealsminke whalesvarious other species of pinnipeds and cetaceans. Off the coast of Norway, some killer whales feed mainly, often in a coordinated manner, on: herringother schooling fish. In waters off New Zealand, some killer whales feed on: In Antarctic waters, there are different types of killer whales. They have each been observed feeding off of various species: type 'A' killer whales feed on minke whalestype 'B' killer whales feed on seals within the seasonal ice packtype 'C' killer whales feed on Antarctic toothfish and other fish species. Acoustic Behavior. Like all cetaceans, killer whales depend heavily on underwater sound for orientation, feeding, and communication. Killer whales produce three categories of sounds: clickswhistlespulsed calls. Echolocation clicks are believed to be used primarily for navigation and discriminating prey and other objects in the surrounding environment, but are also commonly heard during social interactions and may have a communicative function. Whistles and pulsed calls are believed to be used for communication and during social activities. Whistles are frequency modulated sounds (pitch changes with time) with multiple harmonics. Pulsed calls are the most common type of vocalization in killer whales and resemble squeaks, screams, and squawks to the human ear. Most calls are highly distinctive in structure, and are characterized by rapid changes in tone and pulse repetition rate. Killer whales of different populations have distinct calls and whistles. In resident killer whales of the eastern North Pacific, each pod possesses a unique repertoire of discrete calls – representing community dialects – which are learned and culturally transmitted among individuals. These calls serve as family badges and are used to maintain group cohesion. In instances with high levels of noise, killer whales are known to increase the amplitude (i. Habitat. Killer whales are most abundant in colder waters, including Antarctica, Norway, and Alaska. However, killer whales can also be fairly abundant in temperate waters. Killer whales also occur, though at lower densities, in tropical, subtropical, and offshore waters. Following the listing of the Southern Residents as an endangered species in 2. November 2. 00. 6. In February 2. 01. Southern Residents. They are most abundant in colder waters, including Antarctica, the North Atlantic and Pacific Oceans, though they also occur, at lower densities, in tropical, subtropical, and offshore waters.
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