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Bryde's whales | |
---|---|
Balaenoptera brydei | |
Balaenoptera edeni | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Artiodactyla |
Infraorder: | Cetacea |
Family: | Balaenopteridae |
Genus: | Balaenoptera |
Species complex: | Bryde's whale complex |
Species | |
| |
Bryde's whale range |
Bryde's whale ( /ˈbrʊdəz/ BRUU-dəz), [3] [4] or the Bryde's whale complex, putatively comprises three species of rorqual and maybe four. The "complex" means the number and classification remains unclear because of a lack of definitive information and research. The common Bryde's whale (Balaenoptera brydei, Olsen, 1913) is a larger form that occurs worldwide in warm temperate and tropical waters, and the Sittang or Eden's whale (Balaenoptera edeni, Anderson, 1879) is a smaller form that may be restricted to the Indo-Pacific. [5] Also, a smaller, coastal form of B. brydei is found off southern Africa, and perhaps another form in the Indo-Pacific differs in skull morphology, tentatively referred to as the Indo-Pacific Bryde's whale. The recently described Omura's whale (B. omurai, Wada et al. 2003), was formerly thought to be a pygmy form of Bryde's, but is now recognized as a distinct species. Rice's whale (B. ricei), which makes its home solely in the Gulf of Mexico, was once considered a distinct population of Bryde's whale, but in 2021 it was described as a separate species.
B. brydei gets its specific and common name from Johan Bryde, Norwegian consul to South Africa, who helped establish the first modern whaling station in the country, while B. edeni gets its specific and common names from Sir Ashley Eden, former High Commissioner of Burma (Myanmar). Sittang whale refers to the type locality of the species.
In Japan, early whalers called it " anchovy " (鰯, iwashi) or " skipjack whale" (鰹鯨, katsuo-kujira カツオクジラ ). It preys on the anchovy and it was commonly associated with the skipjack. As modern whaling shifted to the Sanriku area, whalemen confused the sei whale with it; now iwashi-kujira (鰯鯨, "anchovy whale" イワシクジラ) only applies to the latter. Incidentally, anchovies are dominant prey for both species off Japan. They are now called nitari-kujira (似鯨, "look-alike whale"), for their resemblance to the sei whale. [6]
The taxonomy is poorly characterised. The two genetically distinct, candidate species/subspecies/morphologies are Bryde's whale B. brydei and the Sittang or Eden's whale B. edeni, [7] that differentiate by geographic distribution, inshore/offshore preferences, and size. For both putative species, the scientific name B. edeni is commonly used or they are simply referred to B. cf brydei/edeni. [8]
In 1878, the Scottish zoologist John Anderson, first curator of the Indian Museum in Calcutta, described Balaenoptera edeni, naming it after the former British High Commissioner in Burma, Sir Ashley Eden, who helped obtain the type specimen. Eden's Deputy Commissioner, Major A.G. Duff, sent a Mr Duke, one of his assistants, to Thaybyoo Creek, between the Sittang and Beeling Rivers, on the Gulf of Martaban, where he found a 11-metre (37 ft) whale, which had stranded there in June 1871 after swimming more than 32 kilometres (20 mi) up the creek—it was said to have "exhausted itself by its furious struggles" to get free and "roared like an elephant" before finally expiring. Despite terrible weather, he was able to secure almost the entire skull and nearly all its vertebrae, along with other bones. These were sent to Anderson, who described the specimen, which was physically mature, as a new species. [9] In 1913, the Norwegian scientist Ørjan Olsen, based on the examination of a dozen "sei whales" brought to the whaling stations at Durban and Saldanha, in South Africa, described Balaenoptera brydei, naming it after the Norwegian consul to South Africa Johan Bryde. [7] In 1950, the Dutch scientist G.C.A. Junge, after comparing specimens of B. edeni and B. brydei with a 12-metre (39 ft), physically mature specimen that had stranded on Pulau Sugi, an island between Singapore and Sumatra, in July 1936, synonymized the two species into B. edeni. [9] [10]
In the 1950s it was discovered that there were two types of "sei whale" off Japan, a northern form with longer, finer baleen and shorter ventral grooves and a southern form with shorter, coarser baleen and longer ventral grooves. They also differed in the shape of the palate. The former was caught off northeastern Honshu and eastern Hokkaido, while the latter was taken off western Kyushu and southern Honshu. Both were caught off the Bonin Islands, but at different seasons. It was realized that the northern form were indeed sei whales (B. borealis), but the southern form were Bryde's whale (B. brydei/edeni). [11] A later study revealed that Bryde's caught off Japan exhibited lateral ridges on their rostrum, whereas sei whales lacked this feature. [12]
In the 1960s it was discovered that some of the "sei whales" being caught off Brazil were also Bryde's whales based on the same characters that distinguished the two species off Japan (i.e. three ridges on the rostrum versus one, shape of the palate, texture of the baleen, length of the ventral grooves). [13]
Several differences in anatomy are found between Bryde's and Eden's whales; morphological similarities have caused confusions regarding species identification. [14]
Members of the Bryde's whale complex are moderately-sized rorquals, falling behind sei whales, but being larger than Omura's whale and the relatively small minke whales. The largest measured by Olsen (1913) was a 14.95 m (49.0 ft) female caught off Durban in November 1912, [7] while the longest of each sex measured by Best (1977) at the Donkergat whaling station in Saldanha Bay, South Africa, were a 15.51 m (50.9 ft) female caught in October 1962 and a 14.56 m (47.8 ft) male caught in April 1963; both were the offshore form. [15] At physical maturity, the coastal form off South Africa averages 13.1 m (43 ft) for males and 13.7 m (45 ft) for females, while the South Africa offshore form averages 13.7 and 14.4 m (45 and 47 ft). The coastal form near Japan is slightly smaller, with adult males averaging 12.9 m (42 ft) and adult females 13.3 m (44 ft). At sexual maturity, males average 11.9 m (39 ft) and females 12 m (39 ft) near Japan. Sexual maturity is reached at 8–11 years for both sexes in the offshore form off South Africa. At birth, they are 3.95–4.15 m (13.0–13.6 ft). [16] The body mass of Bryde's whales can range 12–25 metric tons (13–28 short tons).
The Bryde's whale is a baleen whale, more specifically a rorqual belonging to the same group as blue whales and humpback whales. It has twin blowholes with a low splashguard to the front. Like other rorquals, it has no teeth, but has two rows of baleen plates.
Bryde's whales closely resemble their close relative the sei whale. They are remarkably elongated (even more so than fin whales), with the greatest height of the body being one seventh their total length—compared to 1/6.5 to 1/6.75 in fin whales and only 1/5.5 in sei whales. Bryde's are dark smoky grey dorsally and usually white ventrally, whereas sei whales are often a galvanized blue-grey dorsally and have a variably sized white patch on the throat, a posteriorly oriented white anchor-shaped marking between the pectoral fins, and are blue-grey beyond the anus—although Bryde's off South Africa can have a similar irregular white patch on the throat. Bryde's have a straight rostrum with three longitudinal ridges that extend from the blowholes, where the auxiliary ridges begin as depressions, to the tip of the rostrum. The sei whale, like other rorquals, has a single median ridge, as well as a slightly arched rostrum, which is accentuated at the tip. Bryde's usually have dark grey lower jaws, whereas sei whales are lighter grey. Bryde's have 250–370 pairs of short, slate grey baleen plates with long, coarse, lighter grey or white bristles that are 40 cm (16 in) long by 20 cm (7.9 in) wide, while sei whales have longer, black or dark grey baleen plates with short, curling, wool-like bristles. [7]
The 40 to 70 ventral pleats extend to or past the umbilicus, occupying about 58% and 57% of the total length, respectively; sei whales, though, have ventral pleats that extend only halfway between the pectoral fins and umbilicus, occupying only 45–47% of the total body length, whereas their umbilicus is usually 52% of the total body length. Both species are often covered with white or pink oval scars caused by bites from cookie-cutter sharks. [17]
Bryde's whales have an upright, falcate dorsal fin that is up to 46.25 cm (18.21 in) in height, average 34.4 cm (13.5 in), and is usually between 30 and 37.5 cm (11.8 and 14.8 in). [15] It is often frayed or ragged along its rear margin and located about two-thirds of the way along the back. The broad, centrally notched tail flukes rarely break the surface. The flippers are small and slender. [8]
Their blow is columnar or bushy, about 3.0–4.0 m (10–13 ft) high. Sometimes, they blow or exhale while under water. Bryde's whales display seemingly erratic behaviour compared to other baleen whales, because they surface at irregular intervals and can change directions for unknown reasons. [8]
They usually appear individually or in pairs, and occasionally in loose aggregations up to 20 animals around feeding areas. [8] They are more active on the water surface than sei whales, especially in coastal waters.
They regularly dive for about 5–15 minutes (maximum of 20 minutes) after four to seven blows. Bryde's whales are capable of reaching depths down to 292 metres (958 ft). [18] When submerging, these whales do not display their flukes. Bryde's whales commonly swim at 1.6–6.4 km/h (1–4 mph), but can reach 19–24 km/h (12–15 mph). [8] They sometimes generate short (0.4 seconds) powerful, low-frequency vocalizations that resemble a human moan. [8]
Bryde's whales feed on a wide variety of fish, planktonic crustaceans, and cephalopods. In the western North Pacific, Bryde's whales caught by Japanese scientific whaling vessels (2000–2007) mainly fed on Japanese anchovy (Engraulis japonicus, 52%) and various species of euphausiid (36%, including Euphausia similis , E. gibboides , Thysanoessa gregaria , and Nematoscelis difficilis ), as well as oceanic lightfish (Vinciguerria nimbaria, nearly 3%), and mackerels (Scomber spp., less than 2%). The prey differed by location and season. In coastal areas, euphausiids dominated the diet, comprising 89 and 75% of the diet in May and June, respectively. Further offshore, Japanese anchovy was the dominant species, accounting for nearly 100% of the diet in late summer. [19] Based on the stomach contents of Bryde's whales caught by Japanese pelagic whaling expeditions in the North Pacific in the 1970s, the majority were found to feed on euphausiids (nearly 89%), whereas only about 11% fed on fish. [20]
Off South Africa, prey preferences differed between the inshore and offshore forms. The former mainly feed on anchovies (Engraulis capensis, 83%), maasbankers (Trachurus trachurus, 36%), and pilchards ( Sardinops ocellata , 33%), with only one (or 3%) being found with euphausiids ( Nyctiphanes capensis ). The latter, however, mainly feed on euphausiids (primarily Euphausia lucens , but also E. recurva , N. capensis , and Thysanoessa gregaria ), as well as various deep-sea fish (including Mueller's pearlside, Maurolicus muelleri, and a species of Lestidium ). One was even found "full of baby squid" (later identified as Lycoteuthis diadema ). [15]
In the Gulf of California, they mainly feed on Pacific sardine (Sardinops sagax) and Pacific thread herring (Opisthonema libertate) (about 88%), but also feed on euphausiids (mostly Nyctiphanes simplex , 11%). They have also been observed feeding on pelagic red crabs ( Pleuroncodes planipes ) off southern Baja California. [21] In the Coral Sea, the South Pacific, and the Indian Ocean, they appear to mainly feed on euphausiids, while off Brazil, they have been observed feeding on sardines. Individuals caught off Western Australia were found with anchovies (E. australis) in their stomachs (though these individuals may refer to Omura's whale). [22] Bryde's whales use several feeding methods, including skimming the surface, lunging, and bubble nets especially within Gulf of Tosa. [8] [23] [24]
Along southeastern coasts of Brazil, whales add twisting movements to lunge feeding. [25]
In the Pacific and northern Indian Ocean, Bryde's whales have been observed employing "tread-water feeding" or "trap feeding," [26] a behaviour more commonly known from the northern Gulf of Thailand which is also performed by humpback whales in the northeastern Pacific. [27] [28]
Bryde's whales breed in alternate years, apparently in any season, with an autumnal peak. Their gestation period is estimated at 12 months. Calves are about 3.4–4.0 m (11–13 ft) long at birth and weigh 1,000 kg (2,200 lb). They become sexually mature at 8–13 years of age, when females are 12 m (39 ft). The mother nurses for 6–12 months. [8]
In 2014, a mysterious sound, dubbed a Biotwang, was discovered in underwater recordings from the Mariana Archipelago. It was assumed to be produced by a baleen whale of unknown species. In 2024 that sound was shown to come from Bryde’s whales. [29] [30]
B. brydei occurs in the Atlantic, Pacific, and Indian Oceans between the 40th parallels of latitude, preferring highly productive, tropical, subtropical, and warm, temperate waters of 16–22 °C (61–72 °F). In the North Pacific, they occur as far north as Honshu to the west and southern California in the east, with vagrants reported as far north as Washington in the United States. They occur throughout the eastern tropical Pacific, including Peru and Ecuador, [31] where they are absent from July to September. They have also been reported in an upwelling area off Chile between 35° and 37°S. In the southwestern Pacific, they occur as far south as the North Island of New Zealand.
Based on osteological features, a specimen from Taiwan was referred to B. brydei, while several specimens from the Philippines and Indonesia differed slightly in skull morphology and were referred to the putative Indo-Pacific Bryde's whale. [1] [32] [33] Mitochondrial DNA analysis showed that Bryde's whales caught in the pelagic western North Pacific and Bonin Islands (resident population), as well as biopsy samples taken from whales off Hawaii, the west coast of Baja California, and the southern Gulf of California, belonged to B. brydei. [34] Resident or semi-resident groups also exist off Hawaiian [35] and Northwestern Hawaiian Islands, [36] and Northern Mariana Islands. [37]
Bryde's whales do not occur within central to northern Sea of Japan on regular basis or at least in large numbers. One of the northernmost records in modern times was of a beached, 5-meter-long specimen at Nakhodka in 2011. [38]
B. brydei occurs throughout the Indian Ocean north of about 35°S. Those of the southern Indian Ocean appear to correspond to B. brydei, as do the individuals illegally caught by the Soviets in the 1960s in the northwest Indian Ocean, as well as the Maldives. Individuals sighted in the Red Sea may or may not be B. brydei. [1] [39]
In the North Atlantic, they have been recorded as far north as Cape Hatteras. They occur throughout the wider Caribbean—two specimens from Aruba were found through mtDNA analysis to be firmly placed within B. brydei and to form a clade with a specimen from Madeira and individuals of the offshore form of South Africa. They were first recorded in the Azores in 2004 and showing mixed traits of offshore and inshore forms, [40] but do not occur in the Mediterranean Sea (regarding the bones of a baleen whale found, Bryde's whale was listed as one of suggested species [41] ). They appear to occur off Brazil year-round, such as around Rio de Janeiro—Cape Frio, [42] Armação dos Búzios, entrance to Guanabara Bay, [43] [44] [45] [42] Ilha Anchieta State Park, Ilha Grande, and so on. Individuals of the inshore form off South Africa are also resident year-round, occurring mainly between Cape Recife and Saldanha Bay, whereas the larger offshore form migrates to West African equatorial waters in the winter. [1] [40] [46] Regular occurrences have been noted around Cape Verde as well. [47]
The type specimen is from the Gulf of Martaban coast of Myanmar, while other referred specimens were found on the Bay of Bengal coast of Myanmar, Bangladesh, India, Thailand to Vietnam, Taiwan and continental China. A population found off southern and southwestern Japan in the East China Sea has also been referred to B. edeni. A whale stranded in Hong Kong and another saved from a river in eastern Australia were found to be closely related to the Junge specimen and the East China Sea whales. Bryde's whale (most had auxiliary ridges) of small size—estimated at 10.1 to 11.6 m (33 to 38 ft) in length—sighted off the northeastern side of the Solomon Islands during a survey in late November and early December 1993 may be referable to B. edeni. Four of the whales, estimated at 11.3 to 11.6 m (37 to 38 ft) in length, were accompanied by calves that ranged from 6.0 to 6.7 m (19.7 to 22.0 ft) in length. [48] It is unknown whether eight small individuals—reaching only 11.2 to 11.7 m (37 to 38 ft) at maturity—caught off western and eastern Australia between 1958 and 1963 are specimens of B. edeni or B. omurai. [1] [32] [49] Along Chinese coasts, for example, whales were once thought to be abundant along southern coasts from Fujian and Guangdong Provinces to Hainan Island and the north-eastern tip of the Gulf of Tonkin [50] [51] [52] [53] [54] such as off Tieshangang District [55] and around Weizhou and Xieyang Islands. [56] [57]
The population may include up to 90,000–100,000 animals worldwide, with two-thirds inhabiting the Northern Hemisphere.[ citation needed ]
For management purposes, the U.S. population is divided into three groups: the Eastern Tropical Pacific stock (11,000–13,000 animals) and the Hawaiian stock (350–500) and an endangered stock of about 100 whales in the Gulf of Mexico. [58] As of 2016, the Bryde's whale is considered to be critically endangered in New Zealand as there are approximately 200 left in the wild. [59]
Prior to 2006, only two confirmed sightings of Bryde's whale had been reported in the eastern North Pacific north of Baja California—one in January 1963, only a kilometer off La Jolla (originally misidentified as a fin whale), and another in October 1991 west of Monterey Bay. Between August 2006 and September 2010, six sightings were made by scientists in the Southern California Bight. Five were west of San Clemente Island, and one between San Clemente Island and Santa Catalina Island. All but one involved single individuals. [60] Another sighting was made off Dana Point, California, on 19 September 2009, which was originally misidentified as a fin whale.
In general, data are insufficient to determine population trends.
Balaenoptera edeni is listed as least concern by the International Union for the Conservation of Nature and Natural Resources. [1]
It is listed in Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) Appendix I, which prohibits commercial international trade. [2]
Balaenoptera brydei has yet to be evaluated.
Bryde's whale is listed on Appendix II [61] of the Convention on the Conservation of Migratory Species of Wild Animals. It is listed on Appendix II [61] as it has an unfavourable conservation status or would benefit significantly from international co-operation organised by tailored agreements.
In addition, Bryde's whale is covered by the Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region (Pacific Cetaceans MOU). [62]
Historically, this species was not significantly targeted by commercial whalers, but became more important in the 1970s as the industry depleted other targets. Artisanal whalers have taken them off the coasts of Indonesia and the Philippines.
Modern whaling for Bryde's whales is thought to have begun from coastal stations in Japan in 1906, where it continued uninterrupted until 1987—they were also caught offshore in the western North Pacific by both Japanese (1971–79) and Soviet (1966–79) fleets, as well as from Taiwan (1976–80), the Bonin Islands (1946–52 and 1981–87), and the Philippines (1983–85). In 1997, an estimated over 20,000 Bryde's whales had been caught in the western North Pacific between 1911 and 1987 (the Japanese were later found to have falsified their reported take from the Bonin Islands between 1981 and 1987, reporting a catch of only 2,659 instead of the true take of 4,162). A population assessment done in the mid-1990s stated that the population in the western North Pacific may have declined by as much as 49% during 1911–96. Norwegian factory ships off Baja California took an additional 34 Bryde's whales between 1924 and 1929; [63] two were also caught off central California in 1966. [64]
An estimated 5,542 Bryde's whales were caught off Peru between 1968 and 1983, including a reported catch of 3,589 between 1973 and 1983. An unknown number were also caught off Chile from 1932 to 1979. Over 2,000 were caught off Cape Province, South Africa, from 1911 to 1967, most (1,300) during 1947–67. The majority of the 2,536 sei whales caught by the pirate whaler Sierra in the South Atlantic between 1969 and 1976 are believed to have been Bryde's whales. At least some Bryde's whales were among the 5,000 sei whales recorded in the catch off Brazil from 1948 to 1977, but possibly only 8%. [1]
Over 30,000 Bryde's whales were caught between 1911 and '87, including over 1,400 taken by the Soviets in the Southern Hemisphere from 1948 to 1973 (only 19 were reported). [65] The peak reported catches were reached in 1973–74 and 1974–75, when over 1,800 were taken each year.
Around 2011, a videographer named Michael Fishbach filmed a Bryde's whale weighing 20 tonnes (20,000 kg) being hunted and killed by a pack of 20 orca in the Sea of Cortez. [66]
Bryde's whales have not been reported as taken or injured in fishing operations. They are sometimes killed or injured by ship strikes. Anthropogenic noise is an increasing concern for all rorquals, which communicate by low-frequency sounds. [8]
These whales are protected off the US by the Marine Mammal Protection Act of 1972. [8]
In March 2019, a diver off the coast of South Africa was accidentally caught in the mouth of a feeding Bryde's whale. [67] The diver and tour-operator, Rainer Schimpf, was photographing sharks circling a bait-ball of fish, when the whale suddenly appeared from below and opened its mouth near the surface in an attempt to swallow the fish. In doing so, it accidentally engulfed Schimpf as well; his entire upper body (down to his waist) went into the whale's mouth. The whale gripped him with its jaws for a few moments as Schimpf held his breath and feared the whale would deep dive. Soon after the whale submerged again, it quickly spat Schimpf (who was unharmed) back out and swam away. [68]
Tourists on jet skis have harassed whales off the gulf coast of Phetchaburi Province, Thailand. [69]
The blue whale is a marine mammal and a baleen whale. Reaching a maximum confirmed length of 29.9 m (98 ft) and weighing up to 199 t, it is the largest animal known ever to have existed. The blue whale's long and slender body can be of various shades of greyish-blue on its upper surface and somewhat lighter underneath. Four subspecies are recognized: B. m. musculus in the North Atlantic and North Pacific, B. m. intermedia in the Southern Ocean, B. m. brevicauda in the Indian Ocean and South Pacific Ocean, and B. m. indica in the Northern Indian Ocean. There is a population in the waters off Chile that may constitute a fifth subspecies.
The gray whale, also known as the grey whale, is a baleen whale that migrates between feeding and breeding grounds yearly. It reaches a length of 14.9 meters (49 ft), a weight of up to 41 tonnes (90,000 lb) and lives between 55 and 70 years, although one female was estimated to be 75–80 years of age. The common name of the whale comes from the gray patches and white mottling on its dark skin. Gray whales were once called devil fish because of their fighting behavior when hunted. The gray whale is the sole living species in the genus Eschrichtius. It is the sole living genus in the family Eschrichtiidae, however some recent studies classify it as a member of the family Balaenopteridae. This mammal is descended from filter-feeding whales that appeared during the Neogene.
Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. As an informal and colloquial grouping, they correspond to large members of the infraorder Cetacea, i.e. all cetaceans apart from dolphins and porpoises. Dolphins and porpoises may be considered whales from a formal, cladistic perspective. Whales, dolphins and porpoises belong to the order Cetartiodactyla, which consists of even-toed ungulates. Their closest non-cetacean living relatives are the hippopotamuses, from which they and other cetaceans diverged about 54 million years ago. The two parvorders of whales, baleen whales (Mysticeti) and toothed whales (Odontoceti), are thought to have had their last common ancestor around 34 million years ago. Mysticetes include four extant (living) families: Balaenopteridae, Balaenidae, Cetotheriidae, and Eschrichtiidae. Odontocetes include the Monodontidae, Physeteridae, Kogiidae, and Ziphiidae, as well as the six families of dolphins and porpoises which are not considered whales in the informal sense.
Rorquals are the largest group of baleen whales, comprising the family Balaenopteridae, which contains nine extant species in two genera. They include the largest known animal that has ever lived, the blue whale, which can reach 180 tonnes, and the fin whale, which reaches 120 tonnes ; even the smallest of the group, the northern minke whale, reaches 9 tonnes.
The fin whale, also known as the finback whale or common rorqual, is a species of baleen whale and the second-longest cetacean after the blue whale. The biggest individual reportedly measured 26 m (85 ft) in length, with a maximum recorded weight of 77 to 81 tonnes. The fin whale's body is long, slender and brownish-gray in color, with a paler underside to appear less conspicuous from below (countershading).
Baleen whales, also known as whalebone whales, are marine mammals of the parvorder Mysticeti in the infraorder Cetacea, which use keratinaceous baleen plates in their mouths to sieve planktonic creatures from the water. Mysticeti comprises the families Balaenidae, Balaenopteridae (rorquals), Eschrichtiidae and Cetotheriidae. There are currently 16 species of baleen whales. While cetaceans were historically thought to have descended from mesonychians, molecular evidence instead supports them as a clade of even-toed ungulates (Artiodactyla). Baleen whales split from toothed whales (Odontoceti) around 34 million years ago.
The minke whale, or lesser rorqual, is a species complex of baleen whale. The two species of minke whale are the common minke whale and the Antarctic minke whale. The minke whale was first described by the Danish naturalist Otto Fabricius in 1780, who assumed it must be an already known species and assigned his specimen to Balaena rostrata, a name given to the northern bottlenose whale by Otto Friedrich Müller in 1776. In 1804, Bernard Germain de Lacépède described a juvenile specimen of Balaenoptera acuto-rostrata. The name is a partial translation of Norwegian minkehval, possibly after a Norwegian whaler named Meincke, who mistook a northern minke whale for a blue whale.
The common minke whale or northern minke whale is a species of minke whale within the suborder of baleen whales.
The Antarctic minke whale or southern minke whale is a species of minke whale within the suborder of baleen whales. It is the second smallest rorqual after the common minke whale and the third smallest baleen whale. Although first scientifically described in the mid-19th century, it was not recognized as a distinct species until the 1990s. Once ignored by the whaling industry due to its small size and low oil yield, the Antarctic minke was able to avoid the fate of other baleen whales and maintained a large population into the 21st century, numbering in the hundreds of thousands. Surviving to become the most abundant baleen whale in the world, it is now one of the mainstays of the industry alongside its cosmopolitan counterpart the common minke. It is primarily restricted to the Southern Hemisphere and feeds mainly on euphausiids.
The North Pacific right whale is a very large, thickset baleen whale species that is extremely rare and endangered.
The pygmy right whale is a species of baleen whale. It may be a member of the cetotheres, a family of baleen whales which until 2012 were thought to be extinct; C. marginata has otherwise been considered the sole member of the family Neobalaenidae and is the only member of the genus Caperea. First described by John Edward Gray in 1846, it is the smallest of the baleen whales, ranging between 6 and 6.5 metres in length and 3,000 and 3,500 kilograms in mass. Despite its name, the pygmy right whale may have more in common with the gray whale and rorquals than the bowhead and right whales.
Omura's whale or the dwarf fin whale is a species of rorqual about which very little is known. Before its formal description, it was referred to as a small, dwarf or pygmy form of Bryde's whale by various sources. The common name and specific epithet commemorate Japanese cetologist Hideo Omura.
Balaenoptera is a genus of rorquals containing eight extant species. Balaenoptera comprises all but two of the extant species in its family ; the genus is currently polyphyletic, with the two aforementioned species being phylogenetically nested within it.
The sei whale is a baleen whale. It is one of ten rorqual species, and the third-largest member after the blue and fin whales. It can grow to 19.5 m (64 ft) in length and weigh as much as 28 t. Two subspecies are recognized: B. b. borealis and B. b. schlegelii. The whale's ventral surface has sporadic markings ranging from light grey to white, and its body is usually dark steel grey in colour. It is among the fastest of all cetaceans, and can reach speeds of up to 50 km/h (31 mph) over short distances.
Rice's whale, also known as the Gulf of Mexico whale, is a species of baleen whale endemic to the northern Gulf of Mexico. Initially identified as a subpopulation of the Bryde's whale, genetic and skeletal studies found it to be a distinct species by 2021. In outward appearance, it is virtually identical to the Bryde's whale. Its body is streamlined and sleek, with a uniformly dark charcoal gray dorsal and pale to pinkish underside. A diagnostic feature often used by field scientists to distinguish Rice's whales from whales other than the Bryde's whale is the three prominent ridges that line the top of its head. The species can be distinguished from the Bryde's whale by the shape of the nasal bones, which have wider gaps due to a unique wrapping by the frontal bones, its unique vocal repertoire, and genetic differences.
Cetaceans form an infra-order of marine mammals. In 2020, approximately 86 species of cetaceans had been identified worldwide. Among these species, at least 35 have been sighted in the wider Caribbean region with very widespread distribution and density variations between areas. Caribbean waters are a preferred breeding site for several species of mysticeti, who live further north the rest of the year. The tucuxi and the boto live at the southern periphery of the Caribbean region in the freshwaters of the Amazon River and surrounding drainage basins.
Bryde's (pronounced Brooder's)
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