The Life of Animals | Humpback Whale | The humpback whale (Megaptera novaeangliae) is a species of baleen whale. One of the larger rorquals species, adults range in length from 12-16 meters (39-52 ft) and weigh approximately 36.000 kilograms (79.000 lb). The humpback has a distinctive body shape, with unusually long pectoral fins and a knobbly head. Found in Oceans and seas around the world, humpback whales typically migrate up to 25.000 kilometres (16.000 mi) each year. Humpbacks feed only in summer, in polar waters, and migrate to tropical or sub-tropical waters to breed and give birth in the winter. During the winter, humpbacks fast and live off Their fat reserves.
Humpbacks have a diverse repertoire of feeding methods, including the bubble net feeding technique. Like other large whales, the humpback was and is a target for the Whaling Industry. Due to over-hunting, its population fell by an estimated 90% before a Whaling moratorium was introduced in 1966. There are at least 80.000 humpback whales worldwide. Once hunted to the Brink of extinction, humpbacks are now sought by whale-watchers, particularly off parts of Australia, New Zealand, South America, Canada, and the United States.
Humpback whales are rorquals (family Balaenopteridae), a family That includes the blue whale, the fin whale, the Bryde's whale, the sei whale and the minke whale. Though Cleary related to the giant whales of the genus Balaenoptera, the humpback has been the sole member of its genus since Gray's work in 1846. More recently though, DNA sequencing analysis has indicated the Humpback is more closely related to Certain rorquals, particularly the fin whale (Balaenoptera physalus), and possibly to the gray whale (Eschrichtius robustus), than it is to rorquals Such as the minke whales. The humpback whale was first Identified as "baleine de la Nouvelle Angleterre" by Mathurin Jacques Brisson in his Regnum Animale of 1756.
The specific name means" New Englander "and was Probably given by Brisson due the regular sightings of humpbacks off the coast of New England Humpback whales can easily be Identified by Their stocky bodies with obvious humps and black dorsal coloring. North Pacific, Atlantic, and Southern Ocean humpbacks have distinct migratory Populations the which complete a round-trip each year. The Indian Ocean population does not migrate, prevented by That ocean's northern coastline. Several hypotheses Attempt to explain the humpback's pectoral fins, the which are proportionally The Longest fins of any cetacean. Humpbacks also have 'rete mirable' a heat exchanging system, the which works similarly in humpbacks, sharks and other fish.
Humpbacks have 270 to 400 Darkly colored baleen plates on each side of the mouth. Humpbacks have a 3 meters (9.8 ft) heart-shaped to Bushy blow, or exhalation of water through the blowholes. Because Humpback Whales breathe voluntarily, researchershave That said it is poss ible That the whales shut off only half of the brain Pls sleeping. Early Whalers also noted blows from humpback adults to be 10-20 feet (3.0-6.1 m) high. Humpback milk is 50% fat and pink in color. Males reach sexual maturity at approximately 7 years of age. The humpback whale lifespan ranges from 45-100 years Fully grown, the males average 15-16 meters (49-52 ft). This Visually distinguishes males and females. Male whales have distinctive scars on heads and bodies, some resulting from battles over females.
The varying patterns on the tail flukes are sufficient to identify individuals. Unique visual identification is not currently possible in most cetacean species (other exceptions include orcas and right whales), humpback making the species a popular study. A photographic catalog of all known North Atlantic whales was developed over this period and is currently maintained by the College of the Atlantic Similar photographic identification projects have Begun in the North Pacific by SPLASH (Structure of Populations, Levels of Abundance and Status of Humpbacks), and around the world. Both male and female humpback whales vocalize, however only the males Produce long, loud, complex "songs" for the which the species is famous. Cetaceans have no vocal cords, whales generate so Their song by forcing water through Their massive nasal cavities.
Whales within a large area sing the same song. All North Atlantic humpbacks sing the same song, and Those of the North Pacific sing a different song. Each population's song changes SLOWLY over a period of years without repeating Scientists are unsure of the purpose of whale song. Only males sing, suggesting That one purpose is to attract females. Scientists hypothesize That may keep singing Populations migrating connected. Identified by Their unique tail patterns, these animals made The Longest documented mammalian migration In Australia, two main migratory Populations have been Identified, off the west and east coast respectively. Most monitored stocks of humpback whales have rebounded well since the end of Commercial Whaling, Such as the North Atlantic where stocks are now believed to be approaching pre-hunting levels. However, the species is Considered endangered in some countries, including the United States The United States initiated a status review of the species on August 12, 2009, and is seeking public comment on potential changes to the species listing under the U.S. Endangered Species Act Areas where population data is limited and the species may be at higher risk include the Arabian Sea, the western North Pacific Ocean, the west coast of Africa and parts of Oceania Today, individuals are vulnerable to collisions with ships, entanglement in fishing gear, pollution and noise Like other cetaceans, humpbacks can be injured by excessive noise. In the 19th century, two humpback whales were the resource persons found dead near sites of repeated oceanic sub-bottom blasting, with traumatic injuries and fractures in the ears Once hunted to the Brink of extinction, the humpback has made a dramatic comeback in the North Pacific. A 2008 study estimates the humpback population That That hit a low of 1.500 whales before hunting was banned worldwide, has made a comeback to a population of the between 18.000 and 20.000 Saxitoxin, a paralytic shellfish poisoning (PSP) from contaminated mackerel has been implicated in humpback whale DeathsThe United Kingdom, Among other countries, designated the humpback as a priority species under the national Biodiversity Action PlanIn August 2008, the IUCN changed humpback's status from Vulnerable to Least Concern, although two sub populations Remain endangered The United States is considering Populations of humpback separate listing, so That Smaller groups, Such as North Pacific humpbacks, the which are estimated to number from 18.000 to 20.000 animals, Might Be delisted.
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