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85-547: The bank occurs in the easternmost bay of the Shark Bay World Heritage area . It is a structure 129 kilometres long and around 8 kilometres wide, comprising various communities on sand plains, tidal channels and other coastal habitats. The space taken up is 1030 km, making it the largest seagrass bank in the world. The only other comparable structure is found in the Mediterranean . Shark Bay has

170-637: 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

255-433: 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

340-502: A World Heritage Site in 1991, the site covers an area of 23,000 square kilometres (8,900 sq mi), of which about 70 per cent are marine waters. It includes many protected areas and conservation reserves, including Shark Bay Marine Park , Francois Peron National Park , Hamelin Pool Marine Nature Reserve , Zuytdorp Nature Reserve and numerous protected islands. Denham and Useless Loop both fall within

425-435: 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

510-402: 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

595-569: 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

680-586: A safe haven in which to restore species that are threatened on the mainland. In 1999 the Australian Wildlife Conservancy acquired the 5,816-hectare (14,370-acre) pastoral lease over Faure Island , off Monkey Mia . Sea turtles nest there seasonally and are the subject of studies conducted in conjunction with the Department of Biodiversity, Conservation and Attractions . Shark Bay is an area of major zoological importance. It

765-415: 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

850-569: A type of sedimentary structure , are modern examples of some of the earliest signs of life on Earth, with fossilized stromatolites being found dating from 3.5   billion years ago at North Pole near Marble Bar , in Western Australia, and are considered the type of fossil with the longest continuous presence in the geological record. Shark Bay's modern examples were first identified in 1956 at Hamelin Pool, before that only being known in

935-426: 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

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1020-872: 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

1105-595: 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

1190-445: Is an accepted version of this page 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

1275-766: 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

1360-560: 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

1445-643: Is home to about 10,000 dugongs ('sea cows'), around 12.5% of the world's population, and there are many Indo-Pacific bottlenose dolphins , particularly at Monkey Mia. The dolphins here have been particularly friendly since the 1960s. The area supports 26 threatened Australian mammal species, over 230 species of bird , and nearly 150 species of reptile . It is an important breeding and nursery ground for fish , crustaceans , and coelenterates . There are over 323 fish species, many of them sharks and rays . Some bottlenose dolphins in Shark Bay exhibit one of

1530-500: Is known as the Zuytdorp Cliffs . The bay is located in the transition zone between three major climatic regions and between two major botanical provinces. Peron Peninsula divides the bay and is the home of its largest settlements as well as a National Park at the northern end. Dirk Hartog Island is of historical significance due to landings upon it by early explorers. In 1616, Dirk Hartog landed at Inscription Point on

1615-591: 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

1700-449: 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

1785-547: Is located approximately 800 kilometres (500 mi) north of Perth , on the westernmost point of the Australian continent. UNESCO 's listing of Shark Bay as a World Heritage Site reads: Shark Bay's waters, islands and peninsulas....have a number of exceptional natural features, including one of the largest and most diverse seagrass beds in the world. However, it is for its stromatolites (colonies of microbial mats that form hard, dome-shaped deposits which are said to be

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1870-575: 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

1955-452: 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

2040-405: 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,

2125-826: The Arabian Sea around Oman . This population has also been recorded in 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

2210-431: 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

2295-557: 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

2380-545: 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

2465-565: 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,

2550-737: 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

2635-605: 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

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2720-441: 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

2805-629: 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

2890-611: The Australian Heritage Database describes this natural feature as "internationally significant" for its seagrass diversity, associated marine life, and as "worldwide benchmark for research" into these structures. Shark Bay, Western Australia Shark Bay ( Malgana : Gathaagudu , lit.   'two waters') is a World Heritage Site in the Gascoyne region of Western Australia . The 23,000-square-kilometre (8,900 sq mi) area

2975-598: The Cape Verde population gathers around Iceland and Norway. There 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

3060-505: 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

3145-456: The area was dry land, and rising sea levels flooded Shark Bay between 8,000 BP and 6,000 BP. A considerable number of Aboriginal midden sites have been found, especially on Peron Peninsula and Dirk Hartog Island which provide evidence of some of the foods gathered from the waters and nearby land areas. An expedition led by Dirk Hartog happened upon the area in 1616, becoming the second group of Europeans known to have visited Australia, after

3230-520: The baffle effect of the seagrass communities trap the carbonate deposits of their organisms remains. The endangered Dugong , represented by one of largest remaining populations (over 500 individuals), forages along the Wooramel bank. The area was first documented in 1970, with several studies and applications for environmental protection since that time. The Register of the National Estate at

3315-400: The bay's sandy beaches. The largest fish in the world, the whale shark , gathers in the bay during the April and May full moons. Shark Bay has the largest known area of seagrass , with seagrass meadows covering over 4,000 square kilometres (1,500 sq mi) of the bay. It includes the 1,030-square-kilometre (400 sq mi) Wooramel Seagrass Bank , the largest seagrass bank in

3400-437: The boundary of the site, yet are specifically excluded from it. The bay itself covers an area of 1,300,000 hectares (3,200,000 acres), with an average depth of 9 metres (30 ft). It is divided by shallow banks and has many peninsulas and islands. The coastline is over 1,500 kilometres (930 mi) long. There are about 300 kilometres (190 mi) of limestone cliffs overlooking the bay. One spectacular segment of cliffs

3485-466: 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

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3570-528: 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

3655-517: The crew of Duyfken under Willem Janszoon had visited Cape York in 1606. The area was given the name Shark Bay by the English explorer William Dampier , on 7 August 1699. Shark Bay was also visited by Louis Aleno de St Aloüarn in 1772, Nicolas Baudin from 1801 to 1803 and Louis de Freycinet in 1818. Europeans, mostly pastoralists, settled in Shark Bay during the 1860s to 1870s. Pearling developed rapidly from 1870. Commercial whaling

3740-399: 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

3825-815: The features of the region. Access to Shark Bay is by air via Shark Bay Airport , and by the World Heritage Drive, a 150-kilometre (93 mi) link road between Denham and the Overlander Roadhouse on the North West Coastal Highway . The Shark Bay area has three bioregions within the Interim Biogeographic Regionalisation for Australia (IBRA) system: Carnarvon, Geraldton Sandplains, and Yalgoo. The bioregions are further divided into sub-bioregions: Humpback whale This

3910-416: The few known cases of tool use in marine mammals (along with sea otters ): they protect their nose with a sponge while foraging for food in the sandy sea bottom. Humpback and southern right whales use the waters of the bay as migratory staging post while other species such as Bryde's whale come into the bay less frequently but to feed or rest. The threatened green and loggerhead sea turtles nest on

3995-444: The fossil record. They may, however, be significantly different from fossilised examples, as growth rates may be up to 250 times slower than the estimated growth rates of some Precambrian stromatolites. There is debate, however, over whether this indicates a true difference in growth rate, or if Precambrian growth estimates are instead too high. Hamelin Pool contains the most diverse and abundant examples of living stromatolite forms in

4080-694: 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

4165-446: 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

4250-496: 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

4335-582: 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

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4420-488: 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

4505-601: The growth of commercial whale watching 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,

4590-404: The largest number of seagrass species recorded in one area. Twelve species have been identified in the area, with nine species being found in some locations. The stands or meadows usually comprise one to four species of seagrass. The marine fauna associated with the bank - including fish, crustaceans and echinoderms - are diverse and numerous. These indirectly contribute to the forming of the bank;

4675-490: The last-remaining habitats of two varieties of Australian mammals, hare-wallabies , threatened with extinction. They are used, with numerous other smaller islands throughout the marine park, to release threatened species that are being bred at Project Eden in François Peron National Park. These islands are free of feral non-native animals which might predate upon the threatened species, and so provide

4760-408: 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

4845-419: 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

4930-605: 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

5015-572: The north end of the island and marked his discovery with a pewter plate , inscribed with the date and nailed to a post. This plate was then replaced by Willem de Vlamingh and returned to the Netherlands. It is now kept in the Rijksmuseum . The Shark Bay Discovery Centre in Denham has a replica of this plate. Bernier and Dorre islands in the north-west corner of the heritage area are among

5100-1279: 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

5185-450: The oldest life forms on earth), that the property is most renowned. The property is also famous for its rich marine life including a large population of dugongs , and provides a refuge for a number of other globally threatened species. The bay features Australia's most abundant marine ecosystems . It is a popular fishing spot. The record of Australian Aboriginal occupation of Shark Bay extends to 22,000 years BP . At that time most of

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5270-403: 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

5355-448: 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

5440-467: The seagrasses to form vast expanses of seagrass beds. This has raised the sea floor, making the bay shallower. Seagrasses are the basis of the food chain in Shark Bay, providing home and shelter to various marine species and attracting the dugong population. In Shark Bay's hot, dry climate, evaporation greatly exceeds the annual precipitation rate. Thus, the seawater in the shallow bays becomes very salt-concentrated, or 'hypersaline'. Seagrasses also restrict

5525-530: 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 ,

5610-437: 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

5695-474: 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

5780-617: 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

5865-503: 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

5950-589: 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

6035-568: 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

6120-504: The surface, performing aerial behaviors such as breaching and surface slapping with 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

6205-566: The tidal flow of waters through the bay area, preventing the ocean tides from diluting the sea water. The water of the bay is 1.5 to 2 times more salty than the surrounding ocean waters. Based on growth rate it is believed that about 1,000 years ago cyanobacteria (blue-green algae) began building up stromatolites in Hamelin Pool at the Hamelin Station Reserve in the southern part of the bay. These microbialites ,

6290-413: 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

6375-714: The total area. The Shark Bay Heritage Area has a hot desert climate under the Köppen Climate Classification , with hot, dry summers, and very mild, relatively wet winters. The World Heritage status of the region was created and negotiated in 1991, the first such site in Western Australia. The site was gazetted on the Australian National Heritage List on 21 May 2007 under the Environment and Heritage Legislation Amendment Act (No. 1), 2003 (Cth). Declared as

6460-580: 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

6545-504: 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

6630-554: 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

6715-618: 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

6800-504: 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

6885-737: 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

6970-472: The world and contains a 200-square-kilometre (77 sq mi) Posidonia australis meadow formed by a single plant , the largest in the world. Shark Bay also contains the largest number of seagrass species ever recorded in one place; twelve species have been found, with up to nine occurring together in some places. The seagrasses are a vital part of the complex environment of the bay. Over thousands of years, sediment and shell fragments have accumulated in

7055-766: The world. Other occurrences are found at Lake Clifton near Mandurah and Lake Thetis near Cervantes . It is hypothesized that some stromatolites contain a new form of chlorophyll , chlorophyll f . Facilities around the World Heritage area, provided by the Shire of Shark Bay and the Department of Biodiversity, Conservation and Attractions, include the Shark Bay World Heritage Discovery Centre in Denham which provides interactive displays and comprehensive information about

7140-432: Was conducted in the bay in the first half of the 20th century by Norwegian -owned factory ships and their catcher vessels. In the late 1930s, up to 1,000 humpback whales were taken per season. The heritage-listed area had a population of fewer than 1,000 people as at the 2011 census and a coastline of over 1,500 kilometres (930 mi). The half-dozen small communities making up this population occupy less than 1% of

7225-497: 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

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