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187-404: The humpback whale ( Megaptera novaeangliae ) is a species of baleen whale . It is a rorqual (a member of the family Balaenopteridae ) and is the only species in the genus Megaptera . Adults range in length from 14–17 m (46–56 ft) and weigh up to 40 metric tons (44 short tons). The humpback has a distinctive body shape, with long pectoral fins and tubercles on its head. It
374-475: A clade of even-toed ungulates (Artiodactyla). Baleen whales split from toothed whales (Odontoceti) around 34 million years ago . Baleen whales range in size from the 6 m (20 ft) and 3,000 kg (6,600 lb) pygmy right whale to the 31 m (102 ft) and 190 t (210 short tons) blue whale , the largest known animal to have ever existed. They are sexually dimorphic . Baleen whales can have streamlined or large bodies, depending on
561-632: A lek mating system. Another possibility is that songs bring in foreign whales to populate the breeding grounds. It has also been suggested that humpback whale songs have echolocating properties and may serve to locate other whales. A 2023 study found that as humpback whales numbers have recovered from whaling, singing has become less common. Whale songs are similar among males in a specific area. Males may alter their songs over time, and others in contact with them copy these changes. They have been shown in some cases to spread "horizontally" between neighboring populations throughout successive breeding seasons. In
748-432: A "spillover" of mobbing behavior intended to protect members of its species. The powerful flippers of humpback whales, often infested with large, sharp barnacles , are formidable weapons against orcas. When threatened, they will thresh their flippers and tails keeping the orcas at bay. The great white shark is another confirmed predator of the humpback whale. In 2020, Marine biologists Dines and Gennari et al. , published
935-479: A V-shaped blow. They are surrounded by a fleshy ridge that keeps water away while the whale breathes. The septum that separates the blowholes has two plugs attached to it, making the blowholes water-tight while the whale dives. Like other mammals, the skin of baleen whales has an epidermis , a dermis , a hypodermis , and connective tissue . The epidermis, the pigmented layer, is 5 millimeters (0.2 in) thick, along with connective tissue. The epidermis itself
1122-412: A darker gray to black in color. A mature gray whale can reach 40 t (44 short tons), with a typical range of 15–33 t (17–36 short tons), making them the ninth largest sized species of cetacean. Notable features that distinguish the gray whale from other mysticetes include its baleen that is variously described as cream, off-white, or blond in color and is unusually short. Small depressions on
1309-434: A documented incident of a group of great white sharks exhibiting pack-like behavior to attack and kill a live adult humpback whale. A second incident regarding great white sharks killing humpback whales was documented off the coast of South Africa. The shark recorded instigating the attack was a female nicknamed "Helen". Working alone, the shark attacked a 33 ft (10 m) emaciated and entangled humpback whale by attacking
1496-457: A few mothers linger with their young calves well into May. Whale watching in Baja's lagoons is particularly popular because the whales often come close enough to boats for tourists to pet them. By late March or early April, the returning animals can be seen from Puget Sound to Canada. A population of about 200 gray whales stay along the eastern Pacific coast from Canada to California throughout
1683-437: A fiber-reinforced structure made of intermediate filaments (proteins). The degree of calcification varies between species, with the sei whale having 14.5% hydroxyapatite , a mineral that coats teeth and bones, whereas minke whales have 1–4% hydroxyapatite. In most mammals, keratin structures, such as wool , air-dry, but aquatic whales rely on calcium salts to form on the plates to stiffen them. Baleen plates are attached to
1870-494: A gray whale 30 miles (48 km) south of Nantucket, Massachusetts . Researchers used a genetic approach to estimate pre-whaling abundance based on samples from 42 gray whales, and reported DNA variability at 10 genetic loci consistent with a population size of 76,000–118,000 individuals, three to five times larger than the average census size as measured through 2007. The National Oceanic and Atmospheric Administration has collected surveys of gray whale population since at least
2057-721: A gray whale was sighted off Sunny Isles Beach, Florida . Genetic analysis of fossil and prefossil gray whale remains in the Atlantic Ocean suggests several waves of dispersal from the Pacific to the Atlantic related to successive periods of climactic warming – during the Pleistocene before the last glacial period and the early Holocene immediately following the opening of the Bering Strait . This information and
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#17327729143302244-614: A group of two or three were observed feeding in Izu Ōshima in 1994 for almost a month, two single individuals stayed in Ise Bay for almost two months in the 1980s and in 2012, the first confirmed living individuals in Japanese EEZ in the Sea of Japan and the first of living cow-calf pairs since the end of whaling stayed for about three weeks on the coastline of Teradomari in 2014. One of
2431-479: A handful of capture records support this idea, although migrations into the sea have been confirmed. Recent studies using genetics and acoustics, suggest that there are several wintering sites for western gray whales such as Mexico and the East China sea. However, their wintering ground habits in the western North Pacific are still poorly understood and additional research is needed. Even though South Korea put
2618-655: A historically unique event. That study suggested that over the past 100,000 years there have been several migrations of gray whales between the Pacific and Atlantic, with the most recent large scale migration of this sort occurring about 5,000 years ago. These migrations corresponded to times of relatively high temperatures in the Arctic Ocean. In 2021, one individual was seen in the port of Rabat , Morocco , followed by sightings in Algeria and Italy . In March 2024, New England Aquarium researchers photographed
2805-425: A large amount of water and sieve the slow-moving prey. Males typically mate with more than one female ( polygyny ), although the degree of polygyny varies with the species. Male strategies for reproductive success vary between performing ritual displays ( whale song ) or lek mating . Calves are typically born in the winter and spring months and females bear all the responsibility for raising them. Mothers fast for
2992-482: A laryngeal sac. Humpback whale groups, aside from mothers and calves, typically last for days or weeks at the most. They are normally sighted in small groups though large aggregations form during feeding and among males competing for females. Humpbacks may interact with other cetacean species, such as right whales , fin whales , and bottlenose dolphins . Humpbacks are highly active at the surface, performing aerial behaviors such as breaching and surface slapping with
3179-504: A layer of fat, or blubber , under the skin to keep warm in the cold water. Although baleen whales are widespread, most species prefer the colder waters of the Arctic and Antarctic . Gray whales are specialized for feeding on bottom-dwelling crustaceans . Rorquals are specialized at lunge-feeding, and have a streamlined body to reduce drag while accelerating. Right whales skim-feed, meaning they use their enlarged head to effectively take in
3366-468: A lunge-feeding behavior. Lunge-feeding is where a whale rams a bait ball (a swarm of small fish ) at high speed. Rorquals generally have streamlined physiques to reduce drag in the water while doing this. Balaenids rely on their huge heads, as opposed to the rorquals' throat pleats, to feed effectively. This feeding behavior allows them to grow very big and bulky, without the necessity for a streamlined body. They have callosities , unlike other whales, with
3553-479: A new genus for it, Eschrichtius . Van Beneden & Gervais 1868 were convinced that the bones described by Lilljeborg could not belong to a living species but that they were similar to fossils that Van Beneden had described from the harbour of Antwerp (most of his named species are now considered nomina dubia ) and therefore named the gray whale Plesiocetus robustus , reducing Lilljeborg's and Gray's names to synonyms. Charles Melville Scammon produced one of
3740-568: A phrase. Similar-sounding phrases are repeated in a series grouped into themes, and multiple themes create a song. The function of these songs has been debated, but they may have multiple purposes. There is little evidence to suggest that songs establish dominance among males. However, there have been observations of non-singing males disrupting singers, possibly in aggression. Those who join singers are males who were not previously singing. Females do not appear to approach singers that are alone, but may be drawn to gatherings of singing males, much like
3927-584: A prey of choice, gray whales are opportunistic feeders and can easily switch from feeding planktonically to benthically. When gray whales feed planktonically, they roll onto their right side while their fluke remains above the surface, or they apply the skimming method seen in other baleen whales (skimming the surface with their mouth open). This skimming behavior mainly seems to be used when gray whales are feeding on crab larvae. Other prey items include polychaete worms , herring eggs, various forms of larvae, and small fish. Gray whales feed benthically, by diving to
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#17327729143304114-566: A relatively long period of time over the period of migration, which varies between species. Baleen whales produce a number of infrasonic vocalizations , notably the songs of the humpback whale . The meat, blubber, baleen, and oil of baleen whales have traditionally been used by the indigenous peoples of the Arctic . Once relentlessly hunted by commercial industries for these products, cetaceans are now protected by international law. These protections have allowed their numbers to recover. However,
4301-444: A relatively small brain compared to their body mass . Like other mammals, their brain has a large, folded cerebrum , the part of the brain responsible for memory and processing sensory information. Their cerebrum only makes up about 68% of their brain's weight, as opposed to human's 83%. The cerebellum , the part of the brain responsible for balance and coordination, makes up 18% of their brain's weight, compared to 10% in humans, which
4488-485: A sensory organ located in the middle of the jaw to regulate these functions. Baleen whales have two flippers on the front, near the head. Like all mammals, baleen whales breathe air and must surface periodically to do so. Their nostrils, or blowholes , are situated at the top of the cranium . Baleen whales have two blowholes, as opposed to toothed whales which have one. These paired blowholes are longitudinal slits that converge anteriorly and widen posteriorly, which causes
4675-439: A spherical lens. The retina is surrounded by a reflective layer of cells ( tapetum lucidum ), which bounces light back at the retina, enhancing eyesight in dark areas. However, light is bent more near the surface of the eye when in air as opposed to water; consequently, they can see much better in the air than in the water. The eyeballs are protected by a thick outer layer to prevent abrasions and an oily fluid (instead of tears) on
4862-410: A touring exhibition that traveled to Edinburgh and London . The whale was dissected by Professor John Struthers , who wrote seven papers on its anatomy and an 1889 monograph on the humpback. An albino humpback whale that travels up and down the east coast of Australia became famous in local media because of its rare, all-white appearance. Migaloo is the only known Australian all-white specimen, and
5049-644: A translation error in early copies of Aristotle 's Historia Animalium (in Ancient Greek ), in which " ὁ μῦς τὸ κῆτος " ( ho mus to kētos , "the mouse, the whale so called") was mistakenly translated as " ὁ μυστικῆτος " ( ho mustikētos , "the Mysticetus"), which D. W. Rice (of the Society for Marine Mammalogy ) in Rice 1998 assumed was an ironic reference to the animals' great size. An alternate name for
5236-406: 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
5423-421: A weight of 680 kg (1,500 lb). The body is bulky with a thin rostrum and proportionally long flippers, each around one-third of its body length. It has a short dorsal fin that varies from nearly non-existent to somewhat long and curved. As a rorqual, the humpback has grooves between the tip of the lower jaw and the navel. They are relatively few in number in this species, ranging from 14 to 35. The mouth
5610-871: A wide feeding range but most travel to southeast Alaska and northern British Columbia. The wintering grounds of the Okinawa/Philippines population are mainly around the Russian Far East . There is some evidence for a fifth population somewhere in the northwestern Pacific. These whales are recorded to feed off the Aleutians with a breeding area somewhere south of the Bonin Islands . In the Southern Hemisphere, humpback whales are divided into seven breeding stocks, some of which are further divided into sub-structures. These include
5797-460: A wing-like manner similar to penguins and sea turtles . Flipper movement is continuous. While doing this, baleen whales use their tail fluke to propel themselves forward through vertical motion while using their flippers for steering, much like an otter . Some species leap out of the water, which may allow them to travel faster. Because of their great size, right whales are not flexible or agile like dolphins, and none can move their neck because of
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5984-592: Is a true albino. First sighted in 1991, the whale was named for an indigenous Australian word for "white fella". To prevent sightseers from approaching dangerously close, the Queensland government decreed a 500-m (1600-ft) exclusion zone around him. Migaloo was last seen in June 2020 along the coast of Port Macquarie NSW in Australia. Migaloo has several physical characteristics that can be identified; his dorsal fin
6171-561: Is an archaic word for "whale", which came from Old French baleine , derived from the Latin word balæna , derived itself from the Ancient Greek φάλλαινα (phállaina) . Right whales got their name because of whalers preferring them over other species; they were essentially the "right whale" to catch. Rorquals use throat pleats to expand their mouths, which allow them to feed more effectively. However, rorquals need to build up water pressure in order to expand their mouths, leading to
6358-626: Is approximately 13 1 ⁄ 2 months, with females giving birth every one to three years. In the latter half of the pregnancy, the fetus experiences a rapid growth in length and mass. Similar to the narrow breeding season, most calves are born within a six-week time period in mid January. The calf is born tail first, and measures about 14–16 ft in length, and a weight of 2,000 lbs. Females lactate for approximately seven months following birth, at which point calves are weaned and maternal care begins to decrease. The shallow lagoon waters in which gray whales reproduce are believed to protect
6545-432: Is believed to be the longest annual migration of any mammal . By mid-December to early January, the majority are usually found between Monterey and San Diego such as at Morro bay , often visible from shore. The whale watching industry provides ecotourists and marine mammal enthusiasts the opportunity to see groups of gray whales as they migrate. By late December to early January, eastern grays begin to arrive in
6732-761: Is considered to be endangered . In most areas, humpback whale populations have recovered from historic whaling, particularly in the North Pacific. Such recoveries have led to the downlisting of the species' threatened status in the United States, Canada, and Australia. In Costa Rica, Ballena Marine National Park was established for humpback protection. Humpbacks still face various other man-made threats, including entanglement by fishing gear, vessel collisions, human-caused noise and traffic disturbance, coastal habitat destruction, and climate change. Like other cetaceans, humpbacks can be injured by excessive noise. In
6919-455: Is disturbed by vibrations, it triggers sensory hairs which send electric current to the brain, where vibrations are processed into sound. Baleen whales have a small, yet functional, vomeronasal organ . This allows baleen whales to detect chemicals and pheromones released by their prey. It is thought that 'tasting' the water is important for finding prey and tracking down other whales. They are believed to have an impaired sense of smell due to
7106-557: Is further divided into C1, C2, C3, and C4 subpopulations; C1 occurs around Mozambique and eastern South Africa, C2 around the Comoro Islands , C3 off the southern and eastern coast of Madagascar and C4 around the Mascarene Islands . The feeding range of this population is likely between coordinates 5°W and 60°E and under 50°S . There may be overlap in the feeding areas of stocks B and C. Stock D whales breed off
7293-591: Is known for breaching and other distinctive surface behaviors , making it popular with whale watchers . Males produce a complex song typically lasting 4 to 33 minutes. Found in oceans and seas around the world, humpback whales typically migrate up to 16,000 km (9,900 mi) each year. They feed in polar waters and migrate to tropical or subtropical waters to breed and give birth. Their diet consists mostly of krill and small fish , and they use bubbles to catch prey. They are promiscuous breeders, with both sexes having multiple partners. Orcas are
7480-428: Is likely due to climate change which caused seasonally shifting accumulations of plankton in various parts of the world, necessitating travel over long distances, as well as the ability to feed on large baitballs to make such trips worthwhile. A 2017 analysis of body size based on data from the fossil record and modern baleen whales indicates that the evolution of gigantism in baleen whales occurred rather recently, within
7667-444: Is lined with baleen plates, which number 270–400 for both sides. The dorsal or upper-side of the animal is generally black; the ventral or underside has various levels of black and white coloration. Whales in the southern hemisphere tend to have more white pigmentation. The flippers can vary from all-white to white only on the undersurface. The varying color patterns and scars on the tail flukes distinguish individual animals. The end of
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7854-501: Is only 1 millimeter (0.04 in) thick. The dermis, the layer underneath the epidermis, is also thin. The hypodermis, containing blubber, is the thickest part of the skin and functions as a means to conserve heat. Right whales have the thickest hypodermis of any cetacean, averaging 51 centimeters (20 in), though, as in all whales, it is thinner around openings (such as the blowhole) and limbs. Blubber may also be used to store energy during times of fasting. The connective tissue between
8041-622: Is only one confirmed record of accidentally killing of the species in Vietnam, at Ngoc Vung Island off Ha Long Bay in 1994 and the skeleton is on exhibition at the Quang Ninh Provincial Historical Museum. Gray whales are known to occur in Taiwan Strait even in recent years. It is also unknown whether any winter breeding grounds ever existed beyond Chinese coasts. For example, it is not known if
8228-472: Is probably due to the great degree of control necessary for constantly swimming. Necropsies on the brains of gray whales revealed iron oxide particles, which may allow them to find magnetic north like a compass . Unlike most animals, whales are conscious breathers. All mammals sleep, but whales cannot afford to become unconscious for long because they may drown. They are believed to exhibit unihemispheric slow-wave sleep , in which they sleep with half of
8415-573: Is reference to a humpback-blue whale hybrid in the South Pacific , attributed to marine biologist Michael Poole. B. acutorostrata/bonaerensis ( minke whale species complex) [REDACTED] B. musculus ( blue whale ) [REDACTED] B. borealis ( sei whale ) [REDACTED] Eschrichtius robustus ( gray whale ) [REDACTED] B. physalus ( fin whale ) [REDACTED] Megaptera novaeangliae ( humpback whale ) [REDACTED] Modern humpback whale populations originated in
8602-487: Is repeated annually. The gray whale has the longest recorded migration of any mammal, with one traveling 23,000 kilometers (14,000 mi) from the Sea of Okhotsk to the Baja Peninsula . Gray whale The gray whale ( Eschrichtius robustus ), 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),
8789-520: Is some overlap in the summer ranges of these populations, and West Indies humpbacks have been documented feeding further east. Whale visits into the Gulf of Mexico have been infrequent but have occurred in the gulf historically. They were considered to be uncommon in the Mediterranean Sea , but increased sightings, including re-sightings, indicate that more whales may colonize or recolonize it in
8976-449: Is somewhat hooked, and his tail flukes have a unique shape, with edges that are spiked along the lower trailing side. In July 2022, concerns arose that Migaloo had died after a white whale washed up on the shores of Mallacoota beach, however after genetic testing, and noting that the carcass was of a female whale while Migaloo is male, it was confirmed by experts to not be Migaloo. In 1985, Humphrey swam into San Francisco Bay and then up
9163-404: Is that when humpbacks suffered near-extinction during the whaling era, orcas turned to other prey but are now resuming their former practice. There is also evidence that humpback whales will defend against or mob killer whales who are attacking either humpback calves or juveniles as well as members of other species, including seals . The humpback's protection of other species may be unintentional,
9350-414: Is the fastest among baleen whales, having been recorded travelling as fast as 10 m/s (36 km/h; 22 mph), and sustaining a speed of 2.5 m/s (9.0 km/h; 5.6 mph) for an extended period. While feeding, the rorqual jaw expands to a volume that can be bigger than the whale itself; to do this, the mouth inflates. The inflation of the mouth causes the cavum ventrale, the throat pleats on
9537-592: Is the shallow (5–15 m (16–49 ft) depth) shelf off northeastern Sakhalin Island , particularly off the southern portion of Piltun Lagoon, where the main prey species appear to be amphipods and isopods . In some years, the whales have also used an offshore feeding ground in 30–35 m (98–115 ft) depth southeast of Chayvo Bay, where benthic amphipods and cumaceans are the main prey species. Some gray whales have also been seen off western Kamchatka, but to date all whales photographed there are also known from
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#17327729143309724-488: 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 . The gray whale is distributed in a Northeast Pacific (North American), and an endangered Northwest Pacific (Asian), population. North Atlantic populations were extirpated (perhaps by whaling ) on
9911-751: Is thought that their size increased with their dependence on baleen. However, the discovery of a skull of the toothed Llanocetus , the second-oldest mysticete, yielded a total length of 8 meters (26 ft), indicating filter feeding was not a driving feature in mysticete evolution. The discovery of Janjucetus and others like it suggests that baleen evolution went through several transitional phases. Species like Mammalodon colliveri had little to no baleen, while later species like Aetiocetus weltoni had both baleen and teeth, suggesting they had limited filter feeding capabilities; later genera like Cetotherium had no teeth in their mouth, meaning they were fully dependent on baleen and could only filter feed. However,
10098-411: Is unknown where this occurred, but it is generally believed that they, like their descendants, followed plankton migrations. These primitive baleen whales had lost their dentition in favor of baleen, and are believed to have lived on a specialized benthic, plankton, or copepod diet like modern baleen whales. Baleen whales experienced their first radiation in the mid-Miocene . It is thought this radiation
10285-518: Is usually reversed, with the males being larger, but the females of all baleen whales are usually five percent larger than males. Sexual dimorphism is also displayed through whale song , notably in humpback whales where the males of the species sing elaborate songs. Male right whales have bigger callosities than female right whales. The males are generally more scarred than females which is thought to be because of aggression during mating season. The unique lungs of baleen whales are built to collapse under
10472-488: The Arabian Sea has been isolated for 70,000 years. The adult humpback whale is generally 14–15 m (46–49 ft), though longer lengths of 16–17 m (52–56 ft) have been recorded. Females are usually 1–1.5 m (3 ft 3 in – 4 ft 11 in) longer than males. The species can reach body masses of 40 metric tons (44 short tons). Calves are born at around 4.3 m (14 ft) long with
10659-487: The Bering and Chukchi seas and ending in the warm-water lagoons of Mexico's Baja California Peninsula and the southern Gulf of California , they travel along the west coast of Canada, the United States and Mexico. Traveling night and day, the gray whale averages approximately 120 km (75 mi) per day at an average speed of 8 km/h (5 mph). This round trip of 16,000–22,000 km (9,900–13,700 mi)
10846-766: The Gulf of Aden , the Persian Gulf , and off the coasts of Pakistan and India. In the North Atlantic, there are two separate wintering populations, one in the West Indies , from Cuba to northern Venezuela, and the other in the Cape Verde Islands and northwest Africa. During summer, West Indies humpbacks congregate off New England , eastern Canada, and western Greenland , while the Cape Verde population gathers around Iceland and Norway. There
11033-554: The IUCN Red List lists the humpback whale as least-concern , with a worldwide population of around 135,000 whales, of which around 84,000 are mature individuals, and an increasing population trend. Regional estimates are around 13,000 in the North Atlantic, 21,000 in the North Pacific, and 80,000 in the southern hemisphere. For the isolated population in the Arabian Sea, only around 80 individuals remain, and this population
11220-544: The International Whaling Commission (IWC) was founded to oversee the industry. They imposed hunting regulations and created hunting seasons. To prevent extinction , IWC banned commercial humpback whaling in 1966. By then, the global population had been reduced to around 5,000. The Soviet Union deliberately under-recorded its catches; the Soviets reported catching 2,820 between 1947 and 1972, but
11407-569: The Islas Marías , Bahía de Banderas , and Nayarit / Jalisco , and there were two modern calving grounds in Sonora ( Tojahui or Yavaros ) and Sinaloa ( Bahia Santa Maria , Bahia Navachiste, La Reforma, Bahia Altata) until being abandoned in the 1980s. These first whales to arrive are usually pregnant mothers looking for the protection of the lagoons to bear their calves, along with single females seeking mates. By mid-February to mid-March,
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#173277291433011594-544: The Muséum National d'Histoire Naturelle ) and colleagues suggested that, based on phylogenic criteria, there are four extant genera of rorquals. They recommend that the genus Balaenoptera be limited to the fin whale, have minke whales fall under the genus Pterobalaena , and have Rorqualus contain the Sei whale, Bryde's whale, Eden's whale (and by extension Rice's whale), the blue whale, and Omura's whale. The gray whale
11781-534: The North Atlantic right whale is ranked critically endangered by the International Union for Conservation of Nature . Besides hunting, baleen whales also face threats from marine pollution and ocean acidification . It has been speculated that man-made sonar results in strandings . They have rarely been kept in captivity, and this has only been attempted with juveniles or members of one of
11968-531: The Oligocene are the Mammalodontidae ( Mammalodon and Janjucetus ) from Australia . They were small with shortened rostra , and a primitive dental formula ( 3.1.4.3 3.1.4.3 ). In baleen whales, it is thought that enlarged mouths adapted for suction feeding evolved before specializations for bulk filter feeding . In the toothed Oligocene mammalodontid Janjucetus , the symphysis is short and
12155-559: The Ross Sea to the Antarctic Peninsula. Humpback whales were hunted as early as the late 16th century. They were often the first species to be harvested in an area due to this coastal distribution. North Pacific kills alone are estimated at 28,000 during the 20th century. In the same period, over 200,000 humpbacks were taken in the Southern Hemisphere. North Atlantic populations dropped to as low as 700 individuals. In 1946,
12342-735: The Sacramento River towards Rio Vista . Five years later, Humphrey returned and became stuck on a mudflat in San Francisco Bay immediately north of Sierra Point below the view of onlookers from the upper floors of the Dakin Building . He was twice rescued by the Marine Mammal Center and other concerned groups in California. He was pulled off the mudflat with a large cargo net and the help of
12529-447: The Sea of Okhotsk , mainly off Piltun Bay region at the northeastern coast of Sakhalin Island (Russian Federation). There are also occasional sightings off the eastern coast of Kamchatka (Russian Federation) and in other coastal waters of the northern Okhotsk Sea. Its migration routes and wintering grounds are poorly known, the only recent information being from occasional records on both
12716-1147: The Shakotan Peninsula , and islands in the La Pérouse Strait such as Rebun Island and Rishiri Island . These areas may also have included feeding grounds. There are shallow, muddy areas favorable for feeding whales off Shiretoko , such as at Shibetsu , the Notsuke Peninsula , Cape Ochiishi on Nemuro Peninsula , Mutsu Bay , along the Tottori Sand Dunes , in the Suou-nada Sea , and Ōmura Bay . The historical calving grounds were unknown but might have been along southern Chinese coasts from Zhejiang and Fujian Province to Guangdong , especially south of Hailing Island and to near Hong Kong . Possibilities include Daya Bay , Wailou Harbour on Leizhou Peninsula , and possibly as far south as Hainan Province and Guangxi , particularly around Hainan Island . These areas are at
12903-604: The South Orkney Islands and to a lesser extent the Tierra del Fuego of southern Chile. Stock A winters off Brazil and migrates to summer grounds around South Georgia and the South Sandwich Islands . Some stock A individuals have also been recorded off the western Antarctic Peninsula, suggesting an increased blurring of the boundaries between the feeding areas of stocks A and G. Stock B breeds on
13090-656: The US Coast Guard . Both times, he was successfully guided back to the Pacific Ocean using a "sound net" in which people in a flotilla of boats made unpleasant noises behind the whale by banging on steel pipes, a Japanese fishing technique known as oikami . At the same time, the attractive sounds of humpback whales preparing to feed were broadcast from a boat headed towards the open ocean. Baleen whale Baleen whales ( / b ə ˈ l iː n / ), also known as whalebone whales , are marine mammals of
13277-560: The fin whale ( B. physalus ), the Sei whale ( B. borealis ), Bryde's whale ( B. brydei ), Eden's whale ( B. edeni ), Rice's whale ( B. ricei ), the blue whale ( B. musculus ), the common minke whale ( B. acutorostrata ), the Antarctic minke whale ( B. bonaerensis ), Omura's whale ( B. omurai ), the humpback whale ( M. novaeangliae ), and the gray whale ( E. robustus ). In a 2012 review of cetacean taxonomy, Alexandre Hassanin (of
13464-534: The flukes . This is known as the dorsal ridge . The tail itself is 3–3.5 m (10–11 ft) across and deeply notched at the center while its edges taper to a point. The two populations of Pacific gray whales (east and west) are morphologically and phylogenically different. Other than DNA structures, differences in proportions of several body parts and body colors including skeletal features, and length ratios of flippers and baleen plates have been confirmed between Eastern and Western populations, and some claims that
13651-591: The parvorder Mysticeti in the infraorder Cetacea ( whales , dolphins and porpoises ), which use keratinaceous baleen plates (or "whalebone") in their mouths to sieve planktonic creatures from the water. Mysticeti comprises the families Balaenidae ( right and bowhead whales), Balaenopteridae ( rorquals ), Eschrichtiidae (the gray whale ) and Cetotheriidae (the pygmy right whale ). There are currently 16 species of baleen whales. While cetaceans were historically thought to have descended from mesonychians , molecular evidence instead supports them as
13838-539: The respiratory tract to hold gas while diving. Doing so may cause serious complications such as embolism . Unlike other mammals, the lungs of baleen whales lack lobes and are more sacculated. Like in humans, the left lung is smaller than the right to make room for the heart. To conserve oxygen, blood is rerouted from pressure-tolerant-tissue to internal organs, and they have a high concentration of myoglobin which allows them to hold their breath longer. The heart of baleen whales functions similarly to other mammals, with
14025-418: The 17th century. This population ranged at least from Southampton, New York , to Jupiter Island, Florida , the latest from 1675. In his 1835 history of Nantucket Island , Obed Macy wrote that in the early pre-1672 colony a whale of the kind called "scragg" entered the harbor and was pursued and killed by the settlers. A. B. Van Deinse points out that the "scrag whale", described by P. Dudley in 1725 as one of
14212-466: The 1930s when it was finally realised that the extinct Atlantic population was the same species as the extant Pacific population, and the new combination Eschrichtius gibbosus was proposed. The gray whale has a dark slate-gray color and is covered by characteristic gray-white patterns, which are scars left by parasites that drop off in its cold feeding grounds. Individual whales are typically identified using photographs of their dorsal surface, matching
14399-785: The 1960s. They state that "the most recent population estimate [from 2007] was approximately 19,000 whales, with a high probability (88%) that the population is at 'optimum sustainable population' size, as defined by the Marine Mammal Protection Act ." They speculate that the ocean ecosystem has likely changed since the prewhaling era, making a return to prewhaling numbers infeasible. Factors limiting or threatening current population levels include ship strikes, entanglement in fishing gear, and changes in sea-ice coverage associated with climate change. Several whales seen off Sakhalin and on Kamchatka Peninsula have been confirmed to migrate towards eastern side of Pacific and join
14586-438: The 19th century, two humpback whales were found dead near repeated oceanic sub-bottom blasting sites, with traumatic injuries and fractures in the ears. Saxitoxin , a paralytic shellfish poisoning from contaminated mackerel, has been implicated in humpback whale deaths. While oil ingestion is a risk for whales, a 2019 study found that oil did not foul baleen and instead was easily rinsed by flowing water. Whale researchers along
14773-458: The 2018 discovery of the toothless Maiabalaena indicates some lineages evolved toothlessness before baleen. Mystacodon selenensis is the earliest mysticete, dating back to 37 to 33 million years ago ( mya ) in the Late Eocene , and, like other early toothed mysticetes, or "archaeomysticetes", M. selenensis had heterodont dentition used for suction feeding. Archaeomysticetes from
14960-430: The 60 to 100 bpm in humans. When diving, their heart rate will drop to 4 to 15 bpm to conserve oxygen. Like toothed whales, they have a dense network of blood vessels ( rete mirabile ) which prevents heat-loss. Like in most mammals, heat is lost in their extremities , so, in baleen whales, warm blood in the arteries is surrounded by veins to prevent heat loss during transport. As well as this, heat inevitably given off by
15147-596: The Antarctic circumpolar current and its effects on global climate patterns is excluded as being causal for the same reason. Gigantism also was preceded by divergence of different mysticete lineages, meaning multiple lineages arrived at large size independently. It is possible the Plio-Pleistocene increase in seasonally intense upwellings , causing high-prey-density zones, led to gigantism. When swimming, baleen whales rely on their flippers for locomotion in
15334-629: The Atlantic Coast report that there have been more stranded whales with signs of vessel strikes and fishing gear entanglement in recent years than ever before. The NOAA recorded 88 stranded humpback whales between January 2016 and February 2019. This is more than double the number of whales stranded between 2013 and 2016. Because of the increase in stranded whales, NOAA declared an unusual mortality event in April 2017. Virginia Beach Aquarium 's stranding response coordinator, Alexander Costidis, stated
15521-467: The Atlantic and Pacific populations cannot be proven by anatomical data, its skeleton is distinctive and easy to distinguish from that of all other living whales. Many other names have been ascribed to the gray whale, including desert whale, devilfish, gray back, mussel digger and rip sack. The name Eschrichtius gibbosus is sometimes seen; this is dependent on the acceptance of a 1777 description by Erxleben. A number of 18th century authors described
15708-422: The Atlantic coasts of England and Sweden were used by Gray to make the first scientific description of a species then surviving only in Pacific waters. The living Pacific species was described by Cope as Rhachianectes glaucus in 1869. Skeletal comparisons showed the Pacific species to be identical to the Atlantic remains in the 1930s, and Gray's naming has been generally accepted since. Although identity between
15895-503: The DNA analysis of last recorded stranding in China. Differences were also observed between Korean and Chinese specimens. Two Pacific Ocean populations are known to exist: one population that is very low, whose migratory route is presumed to be between the Sea of Okhotsk and southern Korea, and a larger one with a population of about 27,000 individuals in the eastern Pacific traveling between
16082-561: The European coast before 500 CE , and on the American and African Atlantic coasts around the late 17th to early 18th centuries. However, in the 2010s and 2020s there have been rare sightings of gray whales in the North Atlantic , Mediterranean , and even off South Atlantic coasts. The gray whale is traditionally placed as the only living species in its genus and family, Eschrichtius and Eschrichtiidae , but an extinct species
16269-675: The IUCN downlisted the population's conservation status from critically endangered to endangered . The gray whale became extinct in the North Atlantic in the 18th century. They had been seasonal migrants to coastal waters of both sides of Atlantic, including the Baltic Sea , the Wadden Sea , the Gulf of St. Lawrence , the Bay of Fundy , Pamlico Sound and possibly Hudson Bay . Radiocarbon dating of subfossil or fossil European (Belgium,
16456-544: The IWC chair asking the Japanese for their co-operation in sorting out the differences between pro- and anti-whaling nations on the commission, the Japanese whaling fleet agreed to take no humpback whales during the two years it would take to reach a formal agreement. In 2010, the IWC authorized Greenland's native population to hunt a few humpback whales for the following three years. Much of the growth of commercial whale watching
16643-638: The Netherlands, Sweden, the United Kingdom) coastal remains confirms this, with whaling the possible cause for the population's extinction. Remains dating from the Roman epoch were found in the Mediterranean during excavation of the antique harbor of Lattara near Montpellier , France, in 1997, raising the question of whether Atlantic gray whales migrated up and down the coast of Europe from
16830-419: The North Atlantic right whale ( E. glacialis ). Cetotheriidae consists of only one living member: the pygmy right whale ( Caperea marginata ). The first descriptions date back to the 1840s of bones and baleen plates resembling a smaller version of the right whale, and was named Balaena marginata . In 1864, it was moved into the genus Caperea after a skull of another specimen was discovered. Six years later,
17017-452: The Piltun area. Diagram of the gray whale seafloor feeding strategy Predicted distribution models indicate that overall range in the last glacial period was broader or more southerly distributed, and inhabitations in waters where species presences lack in present situation, such as in southern hemisphere and south Asian waters and northern Indian Ocean were possible due to feasibility of
17204-628: The Wadden Sea to calve in the Mediterranean. A 2018 study utilizing ancient DNA barcoding and collagen peptide matrix fingerprinting confirmed that Roman era whale bones east of the Strait of Gibraltar were gray whales (and North Atlantic right whales ), confirming that gray whales once ranged into the Mediterranean. Similarly, radiocarbon dating of American east coastal subfossil remains confirm that gray whales existed there at least through
17391-500: The arteries warms blood in the surrounding veins as it travels back into the core . This is otherwise known as countercurrent exchange . To counteract overheating while in warmer waters, baleen whales reroute blood to the skin to accelerate heat-loss. They have the largest blood corpuscles ( red and white blood cells ) of any mammal, measuring 10 micrometers (4.1 × 10 in) in diameter, as opposed to human's 7.1-micrometer (2.8 × 10 in) blood corpuscles. When sieved from
17578-662: The better documented historical catches show that it was common for whales to stay for months in enclosed waters elsewhere, with known records in the Seto Inland Sea and the Gulf of Tosa. Former feeding areas were once spread over large portions on mid-Honshu to northern Hokkaido, and at least whales were recorded for majority of annual seasons including wintering periods at least along east coasts of Korean Peninsula and Yamaguchi Prefecture . Some recent observations indicate that historic presences of resident whales are possible:
17765-457: The brain while the other half remains active. This behavior was only documented in toothed whales until footage of a humpback whale sleeping (vertically) was shot in 2014. It is largely unknown how baleen whales produce sound because of the lack of a melon and vocal cords . In a 2007 study, it was discovered that the larynx had U-shaped folds which are thought to be similar to vocal cords. They are positioned parallel to air flow, as opposed to
17952-570: The breeding season, it is common for females to have several mates. This single ovulation event is believed to coincide with the species' annual migration patterns, when births can occur in warmer waters. Most females show biennial reproduction, although annual births have been reported. Males also show seasonal changes, experiencing an increase in testes mass that correlates with the time females undergo oestrus. Currently there are no accounts of twin births, although an instance of twins in utero has been reported. The gestation period for gray whales
18139-412: The bulk of the population has arrived in the lagoons, filling them with nursing, calving and mating gray whales. Throughout February and March, the first to leave the lagoons are males and females without new calves. Pregnant females and nursing mothers with their newborns are the last to depart, leaving only when their calves are ready for the journey, which is usually from late March to mid-April. Often,
18326-493: The calving lagoons and bays on the west coast of Baja California Sur . The three most popular are San Ignacio , Magdalena Bay to the south, and, to the north, Laguna Ojo de Liebre (formerly known in English as Scammon's Lagoon after whaleman Charles Melville Scammon , who discovered the lagoons in the 1850s and hunted the grays). Gray whales once ranged into Sea of Cortez and Pacific coasts of continental Mexico south to
18513-653: The capacity of their throats, allowing them to filter larger volumes of water at once. Gray whales are bottom-feeders, meaning they sift through sand to get their food. They usually turn on their sides, scoop up sediment into their mouths and filter out benthic creatures like amphipods , which leave noticeable marks on their heads. The pygmy right whale is easily confused with minke whales because of their similar characteristics, such as their small size, dark gray tops, light gray bottoms, and light eye patches. Molecular phylogeny suggests Mysticeti split from Odontoceti (toothed whales) between 26 and 17 million years ago between
18700-464: The center, often containing at least one fragile hair that erupts 1–3 cm (0.39–1.18 in) from the skin and is 0.1 mm (0.0039 in) thick. The tubercles develop early in the womb and may have a sensory function as they are rich in nerves. Sensory nerve cells in the skin are adapted to withstand the high water pressure of diving. In one study, a humpback whale brain measured 22.4 cm (8.8 in) long and 18 cm (7.1 in) wide at
18887-527: The conclusion that the two causes of these unusual mortality events were vessel interactions and entanglements. In December 1883, a male humpback swam up the Firth of Tay in Scotland, past what was then the whaling port of Dundee . Harpooned during a failed hunt, it was found dead off Stonehaven a week later. Its carcass was exhibited to the public by a local entrepreneur, John Woods, both locally and then as
19074-966: The earliest descriptions of living Pacific gray whales, and notwithstanding that he was among the whalers who nearly drove them to extinction in the lagoons of the Baja California Peninsula , they were and still are associated with him and his description of the species. At this time, however, the extinct Atlantic population was considered a separate species ( Eschrischtius robustus ) from the living Pacific population ( Rhachianectes glaucus ). Things got increasingly confused as 19th century scientists introduced new species at an alarming rate (e.g. Eschrichtius pusillus , E. expansus , E. priscus , E. mysticetoides ), often based on fragmentary specimens, and taxonomists started to use several generic and specific names interchangeably and not always correctly (e.g. Agalephus gobbosus , Balaenoptera robustus , Agalephus gibbosus ). Things got even worse in
19261-486: The eastern and western coasts of Japan and along the Chinese coast. Gray whale had not been observed on Commander Islands until 2016. The northwestern pacific population consists of approximately 300 individuals, based on photo identification collected off of Sakhalin Island and Kamchatka. The Sea of Japan was once thought not to have been a migration route, until several entanglements were recorded. Any records of
19448-631: The eastern population. In mid-1980, there were three gray whale sightings in the eastern Beaufort Sea , placing them 585 kilometers (364 mi) further east than their known range at the time. Recent increases in sightings are confirmed in Arctic areas of the historic range for Atlantic stocks, most notably on several locations in the Laptev Sea including the New Siberian Islands in the East Siberian Sea , and around
19635-430: The end of the mouth. This is probably because they feed on slow or immobile prey, combined with the fact that most sunlight does not pass 9.1 meters (30 ft), and hence they do not need acute vision. A whale's eye is adapted for seeing both in the euphotic and aphotic zones by increasing or decreasing the pupil 's size to prevent damage to the eye. As opposed to land mammals which have a flattened lens , whales have
19822-450: The environment on those days. Range expansions due to recoveries and re-colonization in the future is likely to happen and the predicted range covers wider than that of today. The gray whale undergoes the longest migration of any mammal. Each October, as the northern ice pushes southward, small groups of eastern gray whales in the eastern Pacific start a two- to three-month, 8,000–11,000 km (5,000–6,800 mi) trip south. Beginning in
20009-473: The equator; their summer feeding areas are found in colder waters, including near the polar ice caps. Humpbacks go on vast migrations between their feeding and breeding areas, often crossing the open ocean. The species has been recorded traveling up to 8,000 km (5,000 mi) in one direction. An isolated, non-migratory population feeds and breeds in the northern Indian Ocean, mainly in the Arabian Sea around Oman . This population has also been recorded in
20196-439: The exception of the bowhead whale. Rorquals have a higher proportion of muscle tissue and tend to be negatively buoyant, whereas right whales have a higher proportion of blubber and are positively buoyant. Gray whales are easily distinguished from the other rorquals by their sleet-gray color, dorsal ridges (knuckles on the back), and their gray-white scars left from parasites. As with the other rorquals, their throat pleats increase
20383-484: The feeding behavior, and two limbs that are modified into flippers . The fin whale is the fastest baleen whale, recorded swimming at 10 m/s (36 km/h; 22 mph). Baleen whales use their baleen plates to filter out food from the water by either lunge-feeding or skim-feeding. Baleen whales have fused neck vertebrae , and are unable to turn their heads at all. Baleen whales have two blowholes . Some species are well adapted for diving to great depths. They have
20570-636: The first radiation in the late Oligocene. Eomysticetus and others like it showed no evidence in the skull of echolocation abilities, suggesting they mainly relied on their eyesight for navigation. The eomysticetes had long, flat rostra that lacked teeth and had blowholes located halfway up the dorsal side of the snout. Though the palate is not well-preserved in these specimens, they are thought to have had baleen and been filter feeders. Miocene baleen whales were preyed upon by larger predators like killer sperm whales and megalodon . The lineages of rorquals and right whales split almost 20 mya. It
20757-476: The fused cervical vertebrae ; this sacrifices speed for stability in the water. The hind legs are enclosed inside the body, and are thought to be vestigial organs . However, a 2014 study suggests that the pelvic bone serves as support for whale genitalia . Rorquals, needing to build speed to feed, have several adaptions for reducing drag , including a streamlined body; a small dorsal fin, relative to its size; and lack of external ears or long hair. The fin whale
20944-693: The future. The North Pacific has at least four breeding populations: off Mexico (including Baja California and the Revillagigedos Islands ), Central America, the Hawaiian Islands , and both Okinawa and the Philippines . The Mexican population forages from the Aleutian Islands to California. During the summer, Central American humpbacks are found only off Oregon and California. In contrast, Hawaiian humpbacks have
21131-442: The genital slit of the female is marked by a round feature, known as the hemispherical lobe, which visually distinguishes males and females. Unique among large whales, humpbacks have bumps or tubercles on the head and front edge of the flippers; the tail fluke has a jagged trailing edge . The tubercles on the head are 5–10 cm (2.0–3.9 in) thick at the base and poke up to 6.5 cm (2.6 in). They are mostly hollow in
21318-432: The genus Megaptera , classifying the humpback as Megaptera longipinna , but in 1932, Remington Kellogg reverted the species names to use Borowski's novaeangliae . The common name is derived from the curving of their backs when diving. The generic name Megaptera from the Ancient Greek mega- μεγα ("giant") and ptera / πτερα ("wing") refer to their large front flippers. The specific name means "New Englander" and
21505-626: The gray whale as Balaena gibbosa , the "whale with six bosses", apparently based on a brief note by Dudley 1725 : The Scrag Whale is near a kin to the Fin-back, but instead of a Fin upon his Back, the Ridge of the Afterpart of his Back is cragged with half a Dozen Knobs or Nuckles; he is nearest the right Whale in Figure and for Quantity of Oil; his Bone is white, but won't split. The gray whale
21692-402: The gray whale than they are to some other rorquals, such as the minke whales . The American Society of Mammalogists has followed this classification. John Edward Gray placed it in its own genus in 1865, naming it in honour of physician and zoologist Daniel Frederik Eschricht . The common name of the whale comes from its coloration. The subfossil remains of now extinct gray whales from
21879-578: The grooves. Water is pushed out through the baleen. In the southern hemisphere, humpbacks have been recorded foraging in large compact gatherings numbering up to 200 individuals. Humpbacks typically hunt their prey with bubble-nets , which is considered to be a form of tool use . A group swims in a shrinking circle while blowing air from their blowholes , capturing prey above in a cylinder of bubbles . They may dive up to 20 m (70 ft) performing this technique. Bubble-netting comes in two main forms; upward spirals and double loops. Upward spirals involve
22066-485: The group over 27 years in response to a change in primary prey. The tubercles on the flippers stall the angle of attack , which both maximizes lift and minimizes drag (see tubercle effect ). This, along with the shape of the flippers, allows the whales to make the abrupt turns necessary during bubble-feeding. At Stellwagen Bank off the coast of the US state of Massachusetts , humpback whales have been recorded foraging at
22253-433: The hypodermis and muscles allows only limited movement to occur between them. Unlike toothed whales, baleen whales have small hairs on the top of their head, stretching from the tip of the rostrum to the blowhole, and, in right whales, on the chin. Like other marine mammals , they lack sebaceous and sweat glands. The baleen of baleen whales are keratinous plates. They are made of a calcified, hard α-keratin material,
22440-428: The lack of the olfactory bulb , but they do have an olfactory tract . Baleen whales have few if any taste buds, suggesting they have lost their sense of taste. They do retain salt-receptor taste-buds suggesting that they can taste saltiness. Most species of baleen whale migrate long distances from high latitude waters during spring and summer months to more tropical waters during winter months. This migration cycle
22627-468: The larger eastern population. In January 2011, a gray whale that had been tagged in the western population was tracked as far east as the eastern population range off the coast of British Columbia. Recent findings from either stranded or entangled specimens indicate that the original western population have become functionally extinct, and possibly all the whales that have appeared on Japanese and Chinese coasts in modern times are vagrants or re-colonizers from
22814-413: The last 3 million years. Before 4.5 million years ago, few baleen whales exceeded 10 meters (33 ft) in length; the two largest Miocene species were less than 13 m (43 ft) in length. The initial evolution of baleen and filter feeding long preceded the evolution of gigantic body size, indicating the evolution of novel feeding mechanisms did not cause the evolution of gigantism. The formation of
23001-851: The late Oligocene or middle Miocene , but the earliest Mysticeti fossils date to at least 34 million years ago. Their evolutionary link to archaic toothed cetaceans ( Archaeoceti ) remained unknown until the extinct Janjucetus hunderi was discovered in the early 1990s in Victoria, Australia . While, unlike a modern baleen whale, Janjucetus lacked baleen in its jaw, the anatomy shows sufficient similarity to baleen whales. It appears to have had very limited apparent biosonar capabilities. Its jaw contained teeth, with incisors and canines built for stabbing and molars and premolars built for tearing. These early mysticetes were exceedingly small compared to modern baleen whales, with species like Mammalodon measuring no greater than 3 meters (10 ft). It
23188-1055: The latter. Cetaceans ( whales , dolphins , and porpoises ) and artiodactyls are now classified under the order Cetartiodactyla , often still referred to as Artiodactyla (given that the cetaceans are deeply nested with the artiodactyls). The closest living relatives to baleen whales are toothed whales both from the infraorder Cetacea . Bowhead whale [REDACTED] Southern right whale [REDACTED] North Atlantic right whale [REDACTED] North Pacific right whale [REDACTED] Pygmy right whale [REDACTED] Common minke whale [REDACTED] Southern minke whale [REDACTED] Gray whale [REDACTED] Humpback whale [REDACTED] Fin whale [REDACTED] Blue whale [REDACTED] Omura's whale Eden's whale [REDACTED] Rice's whale [REDACTED] Sei whale [REDACTED] Bryde's whale [REDACTED] Balaenidae consists of two genera: Eubalaena (right whales) and Balaena (the bowhead whale , B. mysticetus ). Balaenidae
23375-406: The lower jaw. The auditory meatus is blocked by connective tissue and an ear plug, which connects to the eardrum . The inner-ear bones are contained in the tympanic bulla , a bony capsule. However, this is attached to the skull, suggesting that vibrations passing through the bone is important. Sinuses may reflect vibrations towards the cochlea . It is known that when the fluid inside the cochlea
23562-408: The main natural predators of humpback whales. Like other large whales, the humpback was a target for the whaling industry. Humans once hunted the species to the brink of extinction ; its population fell to around 5,000 by the 1960s. Numbers have partially recovered to some 135,000 animals worldwide, while entanglement in fishing gear , collisions with ships, and noise pollution continue to affect
23749-435: The major difference being the size. The heart can reach 454 kilograms (1,000 lb), but is still proportional to the whale's size. The muscular wall of the ventricle , which is responsible for pumping blood out of the heart, can be 7.6 to 12.7 centimeters (3 to 5 in) thick. The aorta, an artery , can be 1.9 centimeters (.75 in) thick. Their resting heart rate is 60 to 140 beats per minute (bpm), as opposed to
23936-416: The male that is closest to the female is known as the "principal escort", who fights off the other suitors known as "challengers". Other males, called "secondary escorts", trail further behind and are not directly involved in the conflict. Agonistic behavior between males consists of tail slashing, ramming, and head-butting. Males have also been observed engaging in copulation with each other . Gestation in
24123-589: The marine mammal sanctuary of the Franz Josef Land , indicating possible earlier pioneers of re-colonizations. These whales were darker in body color than those whales seen in Sea of Okhotsk. In May 2010, a gray whale was sighted off the Mediterranean shore of Israel. It has been speculated that this whale crossed from the Pacific to the Atlantic via the Northwest Passage , since an alternative route around Cape Horn would not be contiguous to
24310-580: The most effort into conservation of the species among the Asian nations, there are no confirmed sightings along the Korean Peninsula or even in the Sea of Japan in recent years. The last confirmed record in Korean waters was the sighting of a pair off Bangeojin , Ulsan in 1977. Prior to this, the last was of catches of 5 animals off Ulsan in 1966. There was a possible sighting of a whale within
24497-467: The mouth enlarged, the rostrum is wide, and the edges of the maxillae are thin, indicating an adaptation for suction feeding. The aetiocetid Chonecetus still had teeth, but the presence of a groove on the interior side of each mandible indicates the symphysis was elastic, which would have enabled rotation of each mandible, an initial adaptation for bulk feeding like in modern mysticetes. The first toothless ancestors of baleen whales appeared before
24684-602: The movements of the tail fluke. Humpbacks are able to flap and rotate their flippers in a manner similar to California sea lions . Humpbacks rest at the surface with their bodies lying horizontally. They frequent shallow seamounts, commonly exploring depths of up to 80 meters (260 feet) and occasionally venturing into deep dives reaching up to 616 meters (2,020 feet). These deeper descents are believed to serve various purposes, including navigational guidance, communication with fellow humpback whales, and facilitation of feeding activities. Dives typically do not exceed five minutes during
24871-477: The newborn from sharks and orcas . On 7 January 2014, a pair of newborn or aborted conjoined twin gray whale calves were found dead in the Laguna Ojo de Liebre (Scammon's Lagoon), off the west coast of Mexico. They were joined by their bellies. The whale feeds mainly on benthic crustaceans (such as amphipods and ghost shrimp ), which it eats by turning on its side and scooping up sediments from
25058-1344: The northern hemisphere, songs change more gradually while southern hemisphere songs go through cyclical "revolutions". Humpback whales are reported to make other vocalizations. "Snorts" are quick low-frequency sounds commonly heard among animals in groups consisting of a mother–calf pair and one or more male escort groups. These likely function in mediating interactions within these groups. "Grumbles" are also low in frequency but last longer and are more often made by groups with one or more adult males. They appear to signal body size and may serve to establish social status. "Thwops" and "wops" are frequency modulated vocals, and may serve as contact calls both within and between groups. High-pitched "cries" and "violins" and modulated "shrieks" are normally heard in groups with two or more males and are associated with competition. Humpback whales produce short, low-frequency "grunts" and short, modulated "barks" when joining new groups. Visible scars indicate that orcas prey upon juvenile humpbacks. A 2014 study in Western Australia observed that when available in large numbers, young humpbacks can be attacked and sometimes killed by orcas. Moreover, mothers and (possibly related) adults escort calves to deter such predation. The suggestion
25245-520: The ocean floor and rolling on to their side, (like blue whales, gray whales seem to favor rolling onto their right side) and suck up prey from the sea floor. Gray whales seem to favor feeding planktonically in their feeding grounds, but benthically along their migration route in shallower water. Mostly, the animal feeds in the northern waters during the summer; and opportunistically feeds during its migration, depending primarily on its extensive fat reserves. Another reason for this opportunistic feeding may be
25432-483: The only sighting of this species in the Southern Hemisphere. Photographic identification suggests that this is a different individual than the one spotted in the Mediterranean in 2010. As of July 2013, the Namibian whale was still being seen regularly. In March 2021, a gray whale was sighted near Rabat , the capital of Morocco . In April, additional sightings were made off Algeria and Italy . In December 2023,
25619-423: The original eastern and western groups could have been much more distinct than previously thought, enough to be counted as subspecies. Since the original Asian and Atlantic populations have become extinct, it is difficult to determine the unique features among whales in these stocks. However, there have been observations of some whales showing distinctive, blackish body colors in recent years. This corresponds with
25806-409: The pair returned to the same coasts at the same time of the year in 2015 again. Reviewing on other cases on different locations among Japanese coasts and islands observed during 2015 indicate that spatial or seasonal residencies regardless of being temporal or permanental staying once occurred throughout many parts of Japan or on other coastal Asia. The current western gray whale population summers in
25993-440: The parvorder is "Mystacoceti" (from Greek μύσταξ "mustache" + κῆτος "whale"), which, although obviously more appropriate and occasionally used in the past, has been superseded by "Mysticeti" ( junior synonym ). Mysticetes are also known as baleen whales for their baleen , which they use to sieve plankton and other small organisms from the water. The term "baleen" ( Middle English baleyn, ballayne, ballien, bellane , etc.)
26180-408: The perpendicular vocal cords of terrestrial mammals. These may control air flow and cause vibrations. The walls of the larynx are able to contract which may generate sound with support from the arytenoid cartilages . The muscles surrounding the larynx may expel air rapidly or maintain a constant volume while diving. The eyes of baleen whales are relatively small for their size and are positioned near
26367-427: The population hit an all-time low in 2010, when no new reproductive females were recorded, resulting in a minimum of 26 reproductive females being observed since 1995. Even a very small number of additional annual female deaths will cause the subpopulation to decline. However, as of 2018, evidence has indicated that the western population is markedly increasing in number, especially off Sakhalin Island . Following this,
26554-676: The port of Samcheok in 2015. There had been 24 records along Chinese coasts including sighting, stranding, intended hunts, and bycatches since 1933. The last report of occurrence of the species in Chinese waters was of a stranded semi adult female in the Bohai Sea in 1996, and the only record in Chinese waters in the 21st century was of a fully-grown female being killed by entanglement in Pingtan , China in November, 2007. DNA studies indicated that this individual might have originated from
26741-400: The pressure instead of resisting the pressure which would damage the lungs, enabling some, like the fin whale, to dive to a depth of −470 meters (−1,540 ft). The whale lungs are very efficient at extracting oxygen from the air, usually 80%, whereas humans only extract 20% of oxygen from inhaled air. Lung volume is relatively low compared to terrestrial mammals because of the inability of
26928-529: The pygmy right whale was classified under the family Neobalaenidae. Despite its name, the pygmy right whale is more genetically similar to rorquals and gray whales than to right whales. A study published in 2012, based on bone structure, moved the pygmy right whale from the family Neobalaenidae to the family Cetotheriidae, making it a living fossil ; Neobalaenidae was demoted to subfamily level as Neobalaeninae. Rorquals consist of three genera ( Balaenoptera , Megaptera , and Eschrichtius ) and 11 species:
27115-426: The recent sightings of Pacific gray whales in the Atlantic, suggest that another range expansion to the Atlantic may be starting. Breeding behavior is complex and often involves three or more animals. Both male and female whales reach puberty between the ages of 6 and 12 with an average of eight to nine years. Females show highly synchronized reproduction, undergoing oestrus in late November to early December. During
27302-402: The region. In Hawaii, humpback whales have been recorded vocalizing for as long as seven hours. Songs are divided into layers; "subunits", "units", "subphrases", "phrases" and "themes". A subunit refers to the discontinuities or inflections of a sound while full units are individual sounds, similar to musical notes . A succession of units creates a subphrase, and a collection of subphrases make up
27489-406: The result of population increases, resulting in the whales taking advantage of whatever prey is available, due to increased competition. Feeding areas during migration seem to include the Gulf of California, Monterey Bay and Baja California Sur. Calf gray whales drink 50–80 lb (23–36 kg) of their mothers' 53% fat milk per day. The main feeding habitat of the western Pacific subpopulation
27676-419: The scars and patches associated with parasites that have either fallen off or are still attached. They have two blowholes on top of their head, which can create a distinctive heart-shaped blow at the surface in calm wind conditions. Gray whales measure from 4.9 m (16 ft) in length for newborns to 13–15 m (43–49 ft) for adults (females tend to be slightly larger than adult males). Newborns are
27863-499: The sea floor. This unique feeding selection makes gray whales one of the most strongly reliant on coastal waters among baleen whales. It is classified as a baleen whale and has baleen , or whalebone, which acts like a sieve, to capture small sea animals, including amphipods taken in along with sand, water and other material. Off Vancouver Island, gray whales commonly feed on shrimp-like mysids . When mysids are abundant gray whales are present in fairly large numbers. Despite mysids being
28050-444: The seafloor for sand lances. This involves the whales flushing out the fish by brushing their jaws against the bottom. Mating and breeding take place during the winter months, which is when females reach estrus and males reach peak testosterone and sperm levels. Humpback whales are promiscuous , with both sexes having multiple partners. Males will frequently trail both lone females and cow–calf pairs. These are known as "escorts", and
28237-505: The smallest species. Baleen whales are cetaceans classified under the parvorder Mysticeti, and consist of four extant families : Balaenidae ( right whales ), Balaenopteridae (rorquals), Eschrichtiidae ( gray whale ) and Cetotheriidae ( pygmy right whale ). Balaenids are distinguished by their enlarged head and thick blubber , while rorquals and gray whales generally have a flat head, long throat pleats, and are more streamlined than Balaenids. Rorquals also tend to be longer than
28424-529: The southeastern Pacific (stock G), southwestern Atlantic (stock A), southeastern Atlantic (stock B), southwestern Indian Ocean (stock C), southeastern Indian Ocean (stock D), southwestern Pacific (stock E), and the Oceania stock (stocks E–F). Stock G breeds in tropical and subtropical waters off the west coast of Central and South America and forages along the west coast of the Antarctic Peninsula ,
28611-436: The southern hemisphere around 880,000 years ago and colonized the northern hemisphere 200,000–50,000 years ago. A 2014 genetic study suggested that the separate populations in the North Atlantic, North Pacific, and Southern Oceans have had limited gene flow and are distinct enough to be subspecies , with the scientific names of M. n. novaeangliae , M. n. kuzira and M. n. australis respectively. A non-migratory population in
28798-415: The southern hemisphere is the Antarctic krill . Further north, the northern krill and various species of Euphausia and Thysanoessa are consumed. Fish prey include herring , capelin , sand lances and Atlantic mackerel . Like other rorquals, humpbacks are "gulp feeders", swallowing prey in bulk, while right whales and bowhead whales are skimmers. The whale increases its mouth gape by expanding
28985-444: The southwestern end of the known range. It is unknown whether the whales' normal range once reached further south, to the Gulf of Tonkin . In addition, the existence of historical calving ground on Taiwan and Penghu Islands (with some fossil records and captures ), and any presence in other areas outside of the known ranges off Babuyan Islands in Philippines and coastal Vietnamese waters in Gulf of Tonkin are unknown. There
29172-582: The species had not been confirmed since after 1921 on Kyushu . However, there were numerous records of whales along the Genkai Sea off Yamaguchi Prefecture , in Ine Bay in the Gulf of Wakasa , and in Tsushima . Gray whales, along with other species such as right whales and Baird's beaked whales , were common features off the north eastern coast of Hokkaido near Teshio , Ishikari Bay near Otaru ,
29359-531: The species hunted by the early New England whalers, was almost certainly the gray whale. Since the 2010s, there have been occasional sightings of gray whales in the Atlantic Ocean and in the Mediterranean Sea , including one off the coast of Israel and one off the coast of Namibia . These were presumably migrants from the North Pacific population through the Arctic Ocean . A 2015 study of DNA from subfossil gray whales indicated that this may not be
29546-613: The species lasts 11.5 months, and females reproduce every 2 years. Fetuses start out with teeth and develop their baleen during the very last months of their gestation. Humpback whale births have been rarely observed. One birth witnessed off Madagascar occurred within four minutes. Mothers typically give birth in mid-winter, usually to a single calf. Young start out with furled dorsal fins which straighten and stiffen as they get older. Calves with furled fin spend more time traveling and surfacing to breathe while calves with straighter fins can hold their breaths longer and can rest and circle around at
29733-503: The species. The humpback was first identified as baleine de la Nouvelle Angleterre by Mathurin Jacques Brisson in his Regnum Animale of 1756. In 1781, Georg Heinrich Borowski described the species, converting Brisson's name to its Latin equivalent, Balaena novaeangliae . In 1804, Bernard Germain de Lacépède shifted the humpback from the family Balaenidae , renaming it B. jubartes . In 1846, John Edward Gray created
29920-586: The summer but are normally 15–20 minutes during the winter. As it dives, a humpback typically raises its tail fluke, exposing the underside. Humpbacks have been observed to produce oral "bubble clouds" when near another individual, possibly in the context of "aggression, mate attraction, or play". Humpbacks may also use bubble cloud as "smoke screens" to escape from predators. Humpback whales feed from spring to fall. They are generalist feeders, their main food items being krill , copepods , other plankton and small schooling fish. The most common krill species eaten in
30107-507: The summer, not making the farther trip to Alaskan waters. This summer resident group is known as the Pacific Coast feeding group. Any historical or current presence of similar groups of residents among the western population is currently unknown, however, whalers' logbooks and scientific observations indicate that possible year-round occurrences in Chinese waters and Yellow and Bohai basins were likely to be summering grounds. Some of
30294-565: The surface more. Older calves are also away from their mothers more. Calves suckle for up to a year but can eat adult food in six months. Humpbacks are sexually mature at 5–10 years, depending on the population. Humpback whales possibly live over 50 years. Male humpback whales produce complex songs during the winter breeding season. These vocals range in frequency between 100 Hz and 4 kHz, with harmonics reaching up to 24 kHz or more, and can travel at least 10 km (6.2 mi). Males may sing for between 4 and 33 minutes, depending on
30481-435: The surface of the eye. Baleen whales appear to have limited color vision, as they lack S-cones . The mysticete ear is adapted for hearing underwater, where it can hear sound frequencies as low as 7 Hz and as high as 22 kHz , distinct from odontocetes whose hearing is optimized for ultrasonic frequencies. It is largely unknown how sound is received by baleen whales. Unlike in toothed whales, sound does not pass through
30668-415: The tail ( lobtailing ) and flippers. These may be forms of play and communication and/or for removing parasites. The species is a slower swimmer than other rorquals, cruising at 7.9–15.1 km/h (4.9–9.4 mph). When threatened, a humpback may speed up to 27 km/h (17 mph). Their proportionally long pectoral fins give them great propulsion and allow them to swim in any direction independently of
30855-437: The third stomach, where it meets fat-digesting enzymes, and is then mixed with an alkaline liquid to neutralize the acid from the fore-stomach to prevent damage to the intestinal tract . Their intestinal tract is highly adapted to absorb the most nutrients from food; the walls are folded and contain copious blood vessels , allowing for a greater surface area over which digested food and water can be absorbed. Baleen whales get
31042-412: The tips of the temporal lobes , and weighed around 4.6 kg (10 lb). Its brain has similar complexity to the brains of smaller whales and dolphins. Computer models of the middle ear suggest that the humpback can hear at frequencies between 15 Hz and 3 kHz "when stimulated at the tympanic membrane ", and between 200 Hz and 9 kHz "if stimulated at the thinner region of the tympanic bone adjacent to
31229-577: The true number was over 48,000. As of 2004, hunting was restricted to a few animals each year off the Caribbean island of Bequia in Saint Vincent and the Grenadines . The take is not believed to threaten the local population. Japan had planned to kill 50 humpbacks in the 2007/08 season under its JARPA II research program. The announcement sparked global protests. After a visit to Tokyo by
31416-500: The tympanic membrane". This is consistent with their vocalization ranges. As in all cetaceans, the respiratory tract of the humpback whale is connected to the blow and not the mouth, though appears to be able to unlock the epiglottis and larynx and move them towards the oral cavity, allowing them to blow bubbles from there. The vocal folds of the humpback are more horizontally positioned than those of land mammals which allows them to produce underwater calls. These calls are amplified by
31603-414: The underside stretching to the navel , to expand, increasing the amount of water that the mouth can store. The mandible is connected to the skull by dense fibers and cartilage ( fibrocartilage ), allowing the jaw to swing open at almost a 90° angle. The mandibular symphysis is also fibrocartilaginous, allowing the jaw to bend which lets in more water. To prevent stretching the mouth too far, rorquals have
31790-410: The upper jaw and are absent in the mid-jaw, forming two separate combs of baleen. The plates decrease in size as they go further back into the jaw; the largest ones are called the "main baleen plates" and the smallest ones are called the "accessory plates". Accessory plates taper off into small hairs. Unlike other whales (and most other mammals), the females are larger than the males. Sexual dimorphism
31977-417: The upper jaw each contain a lone stiff hair, but are only visible on close inspection. Its head's ventral surface lacks the numerous prominent furrows of the related rorquals, instead bearing two to five shallow furrows on the throat's underside. The gray whale also lacks a dorsal fin , instead bearing 6 to 12 dorsal crenulations ("knuckles"), which are raised bumps on the midline of its rear quarter, leading to
32164-434: The water they need from their food; however, the salt content of most of their prey ( invertebrates ) is similar to that of seawater, whereas the salt content of a whale's blood is considerably lower (three times lower) than that of seawater. The whale kidney is adapted to excreting excess salt; however, while producing urine more concentrated than seawater, it wastes a lot of water which must be replaced. Baleen whales have
32351-401: The water, food is swallowed and travels through the esophagus where it enters a three-chambered-stomach. The first compartment is known as the fore-stomach; this is where food gets ground up into an acidic liquid, which is then squirted into the main stomach. Like in humans, the food is mixed with hydrochloric acid and protein-digesting enzymes . Then, the partly digested food is moved into
32538-448: The waters off northernmost Alaska and Baja California Sur . Mothers make this journey accompanied by their calves, usually hugging the shore in shallow kelp beds, and fight viciously to protect their young if they are attacked, earning gray whales the moniker, devil fish. The western population has had a very slow growth rate despite heavy conservation action over the years, likely due to their very slow reproduction rate. The state of
32725-552: The west coast of Africa and is further divided into Bl and B2 subpopulations, the former ranging from the Gulf of Guinea to Angola and the latter ranging from Angola to western South Africa. Stock B whales have been recorded foraging in waters to the southwest of the continent, mainly around Bouvet Island . Comparison of songs between those at Cape Lopez and Abrolhos Archipelago indicate that trans-Atlantic mixings between stock A and stock B whales occur. Stock C whales winter around southeastern Africa and surrounding waters. This stock
32912-615: The western coast of Australia, and forage in the southern region of the Kerguelen Plateau . Stock E is divided into E1, E2, and E3 stocks. E1 whales have a breeding range off eastern Australia and Tasmania ; their main feeding range is close to Antarctica, mainly within 130°E and 170°W . The Oceania stock is divided into the New Caledonia (E2), Tonga (E3), Cook Islands (F1) and French Polynesia (F2) subpopulations. This stock's feeding grounds mainly range from around
33099-569: The whale's established territory. There has been gradual melting and recession of Arctic sea ice with extreme loss in 2007 rendering the Northwest Passage "fully navigable". The same whale was sighted again on May 30, 2010, off the coast of Barcelona , Spain. In May 2013, a gray whale was sighted off Walvis Bay , Namibia. Scientists from the Namibian Dolphin Project confirmed the whale's identity and thus provides
33286-500: The whale's tail to cripple and bleed the whale before she managed to drown the whale by biting onto its head and pulling it underwater. Humpback whales are found in marine waters worldwide , except for some areas at the equator and High Arctic and some enclosed seas. The furthest north they have been recorded is at 81°N around northern Franz Josef Land . They are usually coastal and tend to congregate in waters within continental shelves . Their winter breeding grounds are located around
33473-735: The whales blowing air from their blowhole continuously as they circle towards the surface, creating a spiral of bubbles. Double loops consist of a deep, long loop of bubbles that herds the prey, followed by slapping the surface and then a smaller loop that prepares the final capture. Combinations of spiraling and looping have been recorded. After the humpbacks create the "nets", the whales swim into them with their mouths gaping and ready to swallow. Bubble-net feeding has also been observed in solitary humpbacks, which can consume more food per mouthful without tiring, particularly with low-density prey patches. Using network-based diffusion analysis , one study argued that whales learned lobtailing from other whales in
33660-663: The whales visited the southern coasts of the Korean Peninsula, adjacent to the Island of Jeju ), Haiyang Island, the Gulf of Shanghai , or the Zhoushan Archipelago . There is no evidence of historical presence in Japan south of Ōsumi Peninsula ; only one skeleton has been discovered in Miyazaki Prefecture . Hideo Omura once considered the Seto Inland Sea to be a historical breeding ground, but only
33847-556: Was built on the humpback whale. The species' highly active surface behaviors and tendency to become accustomed to boats have made them easy to observe, particularly for photographers. In 1975, humpback whale tours were established in New England and Hawaii. This business brings in a revenue of $ 20 million per year for Hawaii's economy. While Hawaiian tours have tended to be commercial, New England and California whale watching tours have introduced educational components. As of 2018,
34034-555: Was caused by global climate change and major tectonic activity when Antarctica and Australia separated from each other, creating the Antarctic Circumpolar Current . Balaenopterids grew bigger during this time, with species like Balaenoptera sibbaldina perhaps rivaling the blue whale in terms of size, though other studies disagree that any baleen whale grew that large in the Miocene. The increase in size
34221-500: Was discovered and placed in the genus in 2017, the Akishima whale ( E. akishimaensis ). Some recent studies place gray whales as being outside the rorqual clade , but as the closest relatives to the rorquals. But other recent DNA analyses have suggested that certain rorquals of the family Balaenopteridae , such as the humpback whale , Megaptera novaeangliae , and fin whale , Balaenoptera physalus , are more closely related to
34408-411: Was first described as a distinct species by Lilljeborg 1861 based on a subfossil found in the brackish Baltic Sea , apparently a specimen from the now extinct north Atlantic population. Lilljeborg, however, identified it as " Balaenoptera robusta ", a species of rorqual . Gray 1864 realized that the rib and scapula of the specimen was different from those of any known rorquals, and therefore erected
34595-478: Was formerly classified in its own family. The two populations, one in the Sea of Okhotsk and Sea of Japan and the other in eastern Pacific are thought to be genetically and physiologically dissimilar. However, there is some discussion as to whether the gray whale should be classified into its own family, or as a rorqual, with recent studies favoring the latter. The taxonomic name "Mysticeti" ( / ˌ m ɪ s t ɪ ˈ s iː t aɪ / ) apparently derives from
34782-495: Was probably given by Brisson due to regular sightings of humpbacks off the coast of New England . Humpback whales are rorquals , members of the family Balaenopteridae , which includes the blue , fin , Bryde's , sei and minke whales . A 2018 genomic analysis estimates that rorquals diverged from other baleen whales in the late Miocene , between 10.5 and 7.5 million years ago. The humpback and fin whale were found to be sister taxon (see phylogenetic tree below). There
34969-509: Was thought to have consisted of only one genus until studies done through the early 2000s reported that bowhead whales and right whales are morphologically (different skull shape) and phylogenically different. According to a study done by H. C. Rosenbaum (of the American Museum of Natural History ) and colleagues, the North Pacific ( E. japonica ) and Southern right ( E. australis ) whales are more closely related to each other than to
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