HOME

TheInfoList



OR:

The sperm whale or cachalot (''Physeter macrocephalus'') is the largest of the
toothed whale The toothed whales (also called odontocetes, systematic name Odontoceti) are a parvorder of cetaceans that includes dolphins, porpoises, and all other whales possessing teeth, such as the beaked whales and sperm whales. Seventy-three species of t ...
s and the largest toothed
predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill t ...
. It is the only living member of the
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
''
Physeter ''Physeter'' is a genus of toothed whales. There is only one living species in this genus: the sperm whale (''Physeter macrocephalus''). Some extremely poorly known fossil species have also been assigned to the same genus including ''Physeter ant ...
'' and one of three extant
species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...
in the sperm whale family, along with the pygmy sperm whale and dwarf sperm whale of the genus '' Kogia''. The sperm whale is a
pelagic The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or w ...
mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur ...
with a worldwide range, and will migrate seasonally for feeding and breeding. Females and young males live together in groups, while mature males (bulls) live solitary lives outside of the mating season. The females cooperate to protect and
nurse Nursing is a profession within the health care sector focused on the care of individuals, families, and communities so they may attain, maintain, or recover optimal health and quality of life. Nurses may be differentiated from other health ...
their young. Females give birth every four to twenty years, and care for the calves for more than a decade. A mature sperm whale has few natural predators, although calves and weakened adults are sometimes killed by pods of
killer whale The orca or killer whale (''Orcinus orca'') is a toothed whale belonging to the oceanic dolphin family, of which it is the largest member. It is the only extant species in the genus ''Orcinus'' and is recognizable by its black-and-white pat ...
s (orcas). Mature males average in length, with the head representing up to one-third of the animal's length. Plunging to , it is the third deepest diving mammal, exceeded only by the southern elephant seal and
Cuvier's beaked whale The Cuvier's beaked whale, goose-beaked whale, or ziphius (''Ziphius cavirostris'') is the most widely distributed of all beaked whales in the family Ziphiidae. It is smaller than most baleen whales yet large among beaked whales. Cuvier's beaked ...
. The sperm whale uses echolocation and vocalization as loud as 230 decibels (re 1 µPa m) underwater. It has the largest brain on Earth, more than five times heavier than a human's. Sperm whales can live 70 years or more. Spermaceti (sperm oil), from which the whale derives its name, was a prime target of the
whaling Whaling is the process of hunting of whales for their usable products such as meat and blubber, which can be turned into a type of oil that became increasingly important in the Industrial Revolution. It was practiced as an organized industr ...
industry, and was sought after for use in oil lamps, lubricants, and candles. Ambergris, a solid waxy waste product sometimes present in its digestive system, is still highly valued as a fixative in perfumes, among other uses. Beachcombers look out for ambergris as flotsam.
Sperm whaling Sperm whaling is the hunting of the marine mammals for the oil, meat and bone that can be extracted from their bodies. Sperm whales, a large and deep-diving species, produce a waxy substance that was especially useful during the Industrial Revol ...
was a major industry in the 19th century, depicted in the novel '' Moby-Dick''. The species is protected by the International Whaling Commission moratorium, and is listed as vulnerable by the
International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
.


Taxonomy and naming


Etymology

The name "sperm whale" is a clipping of "spermaceti whale". Spermaceti, originally mistakenly identified as the whales'
semen Semen, also known as seminal fluid, is an organic bodily fluid created to contain spermatozoa. It is secreted by the gonads (sexual glands) and other sexual organs of male or hermaphroditic animals and can fertilize the female ovum. Sem ...
, is the semi-liquid, waxy substance found within the whale's head. (''See " Spermaceti organ and melon" below.'') The sperm whale is also known as the "cachalot", which is thought to derive from the archaic French for 'tooth' or 'big teeth', as preserved for example in the word in the Gascon dialect (a word of either Romance or Basque origin). The etymological dictionary of Corominas says the origin is uncertain, but it suggests that it comes from the
Vulgar Latin Vulgar Latin, also known as Popular or Colloquial Latin, is the range of non-formal registers of Latin spoken from the Late Roman Republic onward. Through time, Vulgar Latin would evolve into numerous Romance languages. Its literary counterpa ...
'sword hilts'. The word ''cachalot'' came to English via French from Spanish or Portuguese , perhaps from Galician/Portuguese 'big head'. The term is retained in the Russian word for the animal, (), as well as in many other languages. The scientific genus name ''Physeter'' comes from the Greek (), meaning 'blowpipe, blowhole (of a whale)', or – as a '' pars pro toto'' – 'whale'. The specific name ''macrocephalus'' is Latinized from the Greek ( 'big-headed'), from () + (). Its synonymous specific name ''catodon'' means 'down-tooth', from the Greek elements ('below') and ('tooth'); so named because it has visible teeth only in its lower jaw. (''See " Jaws and teeth" below.'') Another synonym ''australasianus'' ('
Australasia Australasia is a region that comprises Australia, New Zealand and some neighbouring islands in the Pacific Ocean. The term is used in a number of different contexts, including geopolitically, physiogeographically, philologically, and ecologic ...
n') was applied to sperm whales in the Southern Hemisphere.


Taxonomy

The sperm whale belongs to the
order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of ...
Cetartiodactyla, the order containing all
cetaceans Cetacea (; , ) is an infraorder of aquatic mammals that includes whales, dolphins, and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively carnivorous diet. They propel th ...
and
even-toed ungulates The even-toed ungulates (Artiodactyla , ) are ungulates—hoofed animals—which bear weight equally on two (an even number) of their five toes: the third and fourth. The other three toes are either present, absent, vestigial, or pointing poste ...
. It is a member of the unranked clade Cetacea, with all the whales, dolphins, and porpoises, and further classified into Odontoceti, containing all the toothed whales and dolphins. It is the sole extant species of its genus, ''
Physeter ''Physeter'' is a genus of toothed whales. There is only one living species in this genus: the sperm whale (''Physeter macrocephalus''). Some extremely poorly known fossil species have also been assigned to the same genus including ''Physeter ant ...
'', in the family Physeteridae. Two species of the related extant genus '' Kogia'', the pygmy sperm whale ''Kogia breviceps'' and the dwarf sperm whale ''K. sima'', are placed either in this family or in the family
Kogiidae Kogiidae is a family comprising at least two extant species of Cetacea, the pygmy (''Kogia breviceps)'' and dwarf (''K. sima)'' sperm whales. As their common names suggest, they somewhat resemble sperm whales, with squared heads and small lowe ...
. In some taxonomic schemes the families
Kogiidae Kogiidae is a family comprising at least two extant species of Cetacea, the pygmy (''Kogia breviceps)'' and dwarf (''K. sima)'' sperm whales. As their common names suggest, they somewhat resemble sperm whales, with squared heads and small lowe ...
and Physeteridae are combined as the superfamily Physeteroidea (see the separate entry on the sperm whale family). Swedish ichthyologist Peter Artedi described it as ''Physeter catodon'' in his 1738 work ''Genera piscium'', from the report of a beached specimen in the Orkneys in 1693 and two beached in the Netherlands in 1598 and 1601. The 1598 specimen was near Berkhey. The sperm whale is one of the species originally described by
Carl Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, ...
in his landmark 1758 10th edition of ''Systema Naturae''. He recognised four species in the genus ''Physeter''. Experts soon realised that just one such species exists, although there has been debate about whether this should be named ''P. catodon'' or ''P. macrocephalus'', two of the names used by Linnaeus. Both names are still used, although most recent authors now accept ''macrocephalus'' as the valid name, limiting ''catodon'' status to a lesser synonym. Until 1974, the species was generally known as ''P. catodon''. In that year, however, Dutch zoologists Antonius M. Husson and Lipke Holthuis proposed that the correct name should be ''P. macrocephalus'', the second name in the genus ''Physeter'' published by Linnaeus concurrently with ''P. catodon''. This proposition was based on the grounds that the names were synonyms published simultaneously, and, therefore, the ICZN
Principle of the First Reviser The International Code of Zoological Nomenclature (ICZN) is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals. It is also informally known as the ICZN Code, for its publisher, the ...
should apply. In this instance, it led to the choice of ''P. macrocephalus'' over ''P. catodon'', a view re-stated in Holthuis, 1987. This has been adopted by most subsequent authors, although Schevill (1986 and 1987) argued that ''macrocephalus'' was published with an inaccurate description and that therefore only the species ''catodon'' was valid, rendering the principle of "First Reviser" inapplicable. The most recent version of ITIS has altered its usage from ''P. catodon'' to ''P. macrocephalus'', following L. B. Holthuis and more recent (2008) discussions with relevant experts. Furthermore, The Taxonomy Committee of the Society for Marine Mammalogy, the largest international association of marine mammal scientists in the world, officially uses ''Physeter macrocephalus'' when publishing their definitive list of marine mammal species.


Biology


External appearance

The sperm whale is the largest toothed whale and is among the most sexually dimorphic of all
cetacean Cetacea (; , ) is an infraorder of aquatic mammals that includes whales, dolphins, and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively carnivorous diet. They propel th ...
s. Both sexes are about the same size at birth, but mature males are typically 30% to 50% longer and three times as massive as females. Newborn sperm whales are usually between long. Female sperm whales are sexually mature at in length, whilst males are sexually mature at . Female sperm whales are physically mature at about in length and generally do not achieve lengths greater than . Male sperm whales are physically mature at about in length, and larger males can generally achieve . An sperm whale was weighed whole. By contrast, the second largest toothed whale ( Baird's beaked whale) measures up to and weighs up to . There are occasional reports of individual sperm whales achieving even greater lengths, with some historical claims reaching or exceeding . One example is the whale that sank the ''
Essex Essex () is a Ceremonial counties of England, county in the East of England. One of the home counties, it borders Suffolk and Cambridgeshire to the north, the North Sea to the east, Hertfordshire to the west, Kent across the estuary of the Riv ...
'' (one of the incidents behind '' Moby-Dick''), which was claimed to be . However, there is disagreement as to the accuracy of some of these claims, which are often considered exaggerations or as being measured along the curves of the body. An individual measuring was reported from a Soviet whaling fleet near the Kuril Islands in 1950 and is cited by some authors as the largest accurately measured. It has been estimated to weigh . In a review of size variation in marine megafauna, McClain and colleagues noted that the International Whaling Commission's data contained eight individuals larger than . The authors supported a male from the South Pacific in 1933 as the largest recorded. However, sizes like these are rare, with 95% of recorded sperm whales below 15.85 metres (52.0 ft). In 1853, one sperm whale was reported at in length, with a head measuring . Large lower jawbones are held in the British Natural History Museum and the Oxford University Museum of Natural History, measuring and , respectively. The average size of sperm whales has decreased over the years, probably due to pressure from whaling. Another view holds that exploitation by overwhaling had virtually no effect on the size of the bull sperm whales, and their size may have actually increased in current times on the basis of density dependent effects. Old males taken at Solander Islands were recorded to be extremely large and unusually rich in blubbers. The sperm whale's unique body is unlikely to be confused with any other species. The sperm whale's distinctive shape comes from its very large, block-shaped head, which can be one-quarter to one-third of the animal's length. The S-shaped blowhole is located very close to the front of the head and shifted to the whale's left. This gives rise to a distinctive bushy, forward-angled spray. The sperm whale's flukes (tail lobes) are triangular and very thick. Proportionally, they are larger than that of any other cetacean, and are very flexible. The whale lifts its flukes high out of the water as it begins a feeding dive. It has a series of ridges on the back's caudal third instead of a
dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...
. The largest ridge was called the 'hump' by whalers, and can be mistaken for a dorsal fin because of its shape and size. In contrast to the smooth skin of most large whales, its back skin is usually wrinkly and has been likened to a prune by whale-watching enthusiasts. Albinos have been reported.


Skeleton

The ribs are bound to the spine by flexible cartilage, which allows the ribcage to collapse rather than snap under high pressure. While sperm whales are well adapted to diving, repeated dives to great depths have long-term effects. Bones show the same pitting that signals decompression sickness in humans. Older skeletons showed the most extensive pitting, whereas calves showed no damage. This damage may indicate that sperm whales are susceptible to decompression sickness, and sudden surfacing could be lethal to them. Like that of all cetaceans, the spine of the sperm whale has reduced zygapophysial joints, of which the remnants are modified and are positioned higher on the vertebral dorsal spinous process, hugging it laterally, to prevent extensive lateral bending and facilitate more dorso-ventral bending. These evolutionary modifications make the spine more flexible but weaker than the spines of terrestrial vertebrates. Like many cetaceans, the sperm whale has a vestigial pelvis that is not connected to the spine. Like that of other
toothed whale The toothed whales (also called odontocetes, systematic name Odontoceti) are a parvorder of cetaceans that includes dolphins, porpoises, and all other whales possessing teeth, such as the beaked whales and sperm whales. Seventy-three species of t ...
s, the skull of the sperm whale is asymmetrical so as to aid echolocation. Sound waves that strike the whale from different directions will not be channeled in the same way. Within the basin of the cranium, the openings of the bony narial tubes (from which the nasal passages spring) are skewed towards the left side of the skull.


Jaws and teeth

The sperm whale's lower jaw is very narrow and underslung. The sperm whale has 18 to 26 teeth on each side of its lower jaw which fit into sockets in the upper jaw. The teeth are cone-shaped and weigh up to each. The teeth are functional, but do not appear to be necessary for capturing or eating squid, as well-fed animals have been found without teeth or even with deformed jaws. One hypothesis is that the teeth are used in aggression between males. Mature males often show scars which seem to be caused by the teeth. Rudimentary teeth are also present in the upper jaw, but these rarely emerge into the mouth. Analyzing the teeth is the preferred method for determining a whale's age. Like the age-rings in a tree, the teeth build distinct layers of cementum and dentine as they grow.


Brain

The sperm whale
brain A brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as Visual perception, vision. I ...
is the largest known of any modern or extinct animal, weighing on average about (with the smallest known weighing and the largest known weighing ), more than five times heavier than a human's, and has a volume of about 8,000 cm3. Although larger brains generally correlate with higher intelligence, it is not the only factor. Elephants and dolphins also have larger brains than humans. Whitehead, p. 323 The sperm whale has a lower encephalization quotient than many other whale and
dolphin A dolphin is an aquatic mammal within the infraorder Cetacea. Dolphin species belong to the families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the New World river dolphins), Pontoporiidae (the b ...
species, lower than that of non-human anthropoid apes, and much lower than
human Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, cultu ...
s'. The sperm whale's
cerebrum The cerebrum, telencephalon or endbrain is the largest part of the brain containing the cerebral cortex (of the two cerebral hemispheres), as well as several subcortical structures, including the hippocampus, basal ganglia, and olfactory bulb. ...
is the largest in all mammalia, both in absolute and relative terms. The olfactory system is reduced, suggesting that the sperm whale has a poor sense of taste and smell. By contrast, the auditory system is enlarged. The pyramidal tract is poorly developed, reflecting the reduction of its limbs.


Biological systems

The sperm whale respiratory system has adapted to cope with drastic pressure changes when diving. The flexible ribcage allows lung collapse, reducing
nitrogen Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...
intake, and
metabolism Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run ...
can decrease to conserve
oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements ...
. Between dives, the sperm whale surfaces to breathe for about eight minutes before diving again. Odontoceti (toothed whales) breathe air at the surface through a single, S-shaped blowhole, which is extremely skewed to the left. Sperm whales spout (breathe) 3–5 times per minute at rest, increasing to 6–7 times per minute after a dive. The blow is a noisy, single stream that rises up to or more above the surface and points forward and left at a 45° angle. On average, females and juveniles blow every 12.5 seconds before dives, while large males blow every 17.5 seconds before dives. Whitehead, pp. 156–161 A sperm whale killed south of Durban, South Africa, after a 1-hour, 50-minute dive was found with two dogfish (
Scymnodon ''Scymnodon'' is a genus of squaliform sharks in the family Somniosidae. Species There are currently four recognized species in this genus: * ''Scymnodon ichiharai'' Ka. Yano & S. Tanaka (II), 1984 (Japanese velvet dogfish) White, W.T., Vaz, ...
sp.), usually found at the sea floor, in its belly. The sperm whale has the longest intestinal system in the world, exceeding 300 m in larger specimens. Similar to ruminants the sperm whale has a four-chambered stomach. The first secretes no gastric juices and has very thick muscular walls to crush the food (since whales cannot chew) and resist the claw and sucker attacks of swallowed squid. The second chamber is larger and is where digestion takes place. Undigested squid beaks accumulate in the second chamber – as many as 18,000 have been found in some dissected specimens.Archived a
Ghostarchive
and th
Wayback Machine
Most squid beaks are vomited by the whale, but some occasionally make it to the hindgut. Such beaks precipitate the formation of ambergris. In 1959, the heart of a 22 metric-ton (24 short-ton) male taken by whalers was measured to be , about 0.5% of its total mass. The circulatory system has a number of specific adaptations for the aquatic environment. The diameter of the
aortic arch The aortic arch, arch of the aorta, or transverse aortic arch () is the part of the aorta between the ascending and descending aorta. The arch travels backward, so that it ultimately runs to the left of the trachea. Structure The aorta begins ...
increases as it leaves the heart. This bulbous expansion acts as a windkessel, ensuring a steady blood flow as the heart rate slows during diving. The arteries that leave the aortic arch are positioned symmetrically. There is no costocervical artery. There is no direct connection between the internal carotid artery and the vessels of the brain. Their circulatory system has adapted to dive at great depths, as much as for up to 120 minutes. More typical dives are around and 35 minutes in duration. Myoglobin, which stores oxygen in muscle tissue, is much more abundant than in terrestrial animals. The
blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in the cir ...
has a high density of
red blood cell Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "hol ...
s, which contain oxygen-carrying haemoglobin. The oxygenated blood can be directed towards only the brain and other essential organs when oxygen levels deplete. The spermaceti organ may also play a role by adjusting
buoyancy Buoyancy (), or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus the ...
(see
below Below may refer to: *Earth * Ground (disambiguation) *Soil *Floor * Bottom (disambiguation) *Less than *Temperatures below freezing *Hell or underworld People with the surname *Ernst von Below (1863–1955), German World War I general *Fred Below ...
). The arterial
retia mirabilia A rete mirabile ( Latin for "wonderful net"; plural retia mirabilia) is a complex of arteries and veins lying very close to each other, found in some vertebrates, mainly warm-blooded ones. The rete mirabile utilizes countercurrent blood flow with ...
are extraordinarily well-developed. The complex arterial retia mirabilia of the sperm whale are more extensive and larger than those of any other cetacean.


Senses


Spermaceti organ and melon

Atop the whale's skull is positioned a large complex of organs filled with a liquid mixture of fats and waxes called spermaceti. The purpose of this complex is to generate powerful and focused clicking sounds, the existence of which was proven by
Valentine Worthington Lawrence Valentine Worthington (March 6, 1920 – February 10, 1995), better known as Val Worthington was a British-American physical oceanographer. His most noted contributions are the discovery of mode water which he called ''18° water'', fi ...
, and William Schevill when a recording was produced on a research vessel in May 1959. The sperm whale uses these sounds for echolocation and communication. Whitehead, pp. 277–279 The spermaceti organ is like a large barrel of spermaceti. Its surrounding wall, known as the ''case'', is extremely tough and fibrous. The case can hold within it up to 1,900
litre The litre (international spelling) or liter (American English spelling) (SI symbols L and l, other symbol used: ℓ) is a metric unit of volume. It is equal to 1 cubic decimetre (dm3), 1000 cubic centimetres (cm3) or 0.001 cubic metre (m3 ...
s of spermaceti. It is proportionately larger in males. Whitehead, p. 321 This oil is a mixture of
triglyceride A triglyceride (TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids (from ''tri-'' and ''glyceride''). Triglycerides are the main constituents of body fat in humans and other vertebrates, as ...
s and wax esters. The proportion of wax esters in the spermaceti organ increases with the age of the whale: 38–51% in calves, 58–87% in adult females, and 71–94% in adult males. Perrin, p. 1164 The spermaceti at the core of the organ has a higher wax content than the outer areas. The speed of sound in spermaceti is 2,684 m/s (at 40 kHz, 36 °C), making it nearly twice as fast as in the oil in a dolphin's
melon A melon is any of various plants of the family Cucurbitaceae with sweet, edible, and fleshy fruit. The word "melon" can refer to either the plant or specifically to the fruit. Botanically, a melon is a kind of berry, specifically a "pepo". T ...
. Below the spermaceti organ lies the "junk" which consists of compartments of spermaceti separated by cartilage. It is analogous to the
melon A melon is any of various plants of the family Cucurbitaceae with sweet, edible, and fleshy fruit. The word "melon" can refer to either the plant or specifically to the fruit. Botanically, a melon is a kind of berry, specifically a "pepo". T ...
found in other toothed whales. The structure of the junk redistributes physical stress across the skull and may have evolved to protect the head during ramming. Running through the head are two air passages. The left passage runs alongside the spermaceti organ and goes directly to the blowhole, whilst the right passage runs underneath the spermaceti organ and passes air through a pair of phonic lips and into the distal sac at the very front of the nose. The distal sac is connected to the blowhole and the terminus of the left passage. When the whale is submerged, it can close the blowhole, and air that passes through the phonic lips can circulate back to the lungs. The sperm whale, unlike other odontocetes, has only one pair of phonic lips, whereas all other toothed whales have two, and it is located at the front of the nose instead of behind the melon. At the posterior end of this spermaceti complex is the frontal sac, which covers the concave surface of the cranium. The posterior wall of the frontal sac is covered with fluid-filled knobs, which are about 4–13 mm in diameter and separated by narrow grooves. The anterior wall is smooth. The knobbly surface reflects sound waves that come through the spermaceti organ from the phonic lips. The grooves between the knobs trap a film of air that is consistent whatever the orientation or depth of the whale, making it an excellent sound mirror. The spermaceti organs may also help adjust the whale's
buoyancy Buoyancy (), or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus the ...
. It is hypothesized that before the whale dives, cold water enters the organ, and it is likely that the blood vessels constrict, reducing blood flow, and, hence, temperature. The wax therefore solidifies and reduces in volume. The increase in specific density generates a down force of about and allows the whale to dive with less effort. During the hunt, oxygen consumption, together with blood vessel dilation, produces heat and melts the spermaceti, increasing its buoyancy and enabling easy surfacing. However, more recent work has found many problems with this theory including the lack of anatomical structures for the actual heat exchange. Another issue is that if the spermaceti does indeed cool and solidify, it would affect the whale's echolocation ability just when it needs it to hunt in the depths.
Herman Melville Herman Melville ( born Melvill; August 1, 1819 – September 28, 1891) was an American novelist, short story writer, and poet of the American Renaissance period. Among his best-known works are '' Moby-Dick'' (1851); '' Typee'' (1846), a ...
's fictional story '' Moby-Dick'' suggests that the "case" containing the spermaceti serves as a battering ram for use in fights between males. A few famous instances include the well-documented sinking of the ships ''
Essex Essex () is a Ceremonial counties of England, county in the East of England. One of the home counties, it borders Suffolk and Cambridgeshire to the north, the North Sea to the east, Hertfordshire to the west, Kent across the estuary of the Riv ...
'' and '' Ann Alexander'' by attackers estimated to weigh only one-fifth as much as the ships. File:Sperm whale phonic lips (NASA).jpg, The phonic lips. File:Sperm whale exposed frontal sac.jpg, The frontal sac, exposed. Its surface is covered with fluid-filled knobs. File:Sperm whale frontal sac surface close-up.jpg, A piece of the posterior wall of the frontal sac. The grooves between the knobs trap a consistent film of air, making it an excellent sound mirror.


Eyes and vision

The sperm whale's eye does not differ greatly from those of other
toothed whale The toothed whales (also called odontocetes, systematic name Odontoceti) are a parvorder of cetaceans that includes dolphins, porpoises, and all other whales possessing teeth, such as the beaked whales and sperm whales. Seventy-three species of t ...
s except in size. It is the largest among the toothed whales, weighing about 170 g. It is overall ellipsoid in shape, compressed along the visual axis, measuring about 7×7×3 cm. The
cornea The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Along with the anterior chamber and lens, the cornea refracts light, accounting for approximately two-thirds of the eye's total optical ...
is elliptical and the lens is spherical. The
sclera The sclera, also known as the white of the eye or, in older literature, as the tunica albuginea oculi, is the opaque, fibrous, protective, outer layer of the human eye containing mainly collagen and some crucial elastic fiber. In humans, and so ...
is very hard and thick, roughly 1 cm anteriorly and 3 cm posteriorly. There are no ciliary muscles. The
choroid The choroid, also known as the choroidea or choroid coat, is a part of the uvea, the vascular layer of the eye, and contains connective tissues, and lies between the retina and the sclera. The human choroid is thickest at the far extreme rea ...
is very thick and contains a fibrous '' tapetum lucidum''. Like other toothed whales, the sperm whale can retract and protrude its eyes, thanks to a 2-cm-thick retractor muscle attached around the eye at the equator, but are unable to roll the eyes in their sockets. According to Fristrup and Harbison (2002), sperm whale's eyes afford good vision and sensitivity to light. They conjectured that sperm whales use vision to hunt squid, either by detecting silhouettes from below or by detecting bioluminescence. If sperm whales detect silhouettes, Fristrup and Harbison suggested that they hunt upside down, allowing them to use the forward parts of the ventral
visual field The visual field is the "spatial array of visual sensations available to observation in introspectionist psychological experiments". Or simply, visual field can be defined as the entire area that can be seen when an eye is fixed straight at a poin ...
s for binocular vision.


Sleeping

For some time researchers have been aware that pods of sperm whales may sleep for short periods, assuming a vertical position with their heads just below or at the surface, or head down. A 2008 study published in ''
Current Biology ''Current Biology'' is a biweekly peer-reviewed scientific journal that covers all areas of biology, especially molecular biology, cell biology, genetics, neurobiology, ecology, and evolutionary biology. The journal includes research arti ...
'' recorded evidence that whales may sleep with both sides of the brain. It appears that some whales may fall into a deep sleep for about 7 percent of the time, most often between 6 p.m. and midnight.


Genetics

Sperm whales have 21 pairs of chromosomes ( 2n=42). The genome of live whales can be examined by recovering shed skin.


Vocalization complex

After the discovery by
Valentine Worthington Lawrence Valentine Worthington (March 6, 1920 – February 10, 1995), better known as Val Worthington was a British-American physical oceanographer. His most noted contributions are the discovery of mode water which he called ''18° water'', fi ...
and William Schevill confirmed the existence of whale vocalization further studies conducted found that sperm whales are capable of emitting sounds at a volume of 230 decibels–more than an airplane
jet engine A jet engine is a type of reaction engine discharging a fast-moving jet (fluid), jet of heated gas (usually air) that generates thrust by jet propulsion. While this broad definition can include Rocket engine, rocket, Pump-jet, water jet, and ...
at takeoff–the sperm whale is the loudest animal in the world. Sperm whale vocalization is a learned behavior that is clan specific.


Mechanism

When echolocating, the sperm whale emits a directionally focused beam of broadband clicks. Clicks are generated by forcing air through a pair of phonic lips (also known as "monkey lips" or "museau de singe") at the front end of the nose, just below the blowhole. The sound then travels backwards along the length of the nose through the spermaceti organ. Most of the sound energy is then reflected off the frontal sac at the cranium and into the melon, whose lens-like structure focuses it. Some of the sound will reflect back into the spermaceti organ and back towards the front of the whale's nose, where it will be reflected through the spermaceti organ a third time. This back and forth reflection which happens on the scale of a few milliseconds creates a multi-pulse click structure. This multi-pulse click structure allows researchers to measure the whale's spermaceti organ using only the sound of its clicks. Because the interval between pulses of a sperm whale's click is related to the length of the sound producing organ, an individual whale's click is unique to that individual. However, if the whale matures and the size of the spermaceti organ increases, the tone of the whale's click will also change. The lower jaw is the primary reception path for the echoes. A continuous fat-filled canal transmits received sounds to the inner ear.Whitlow, W. "Echolocation", pp. 359–367 in Perrin The source of the air forced through the phonic lips is the right nasal passage. While the left nasal passage opens to the blow hole, the right nasal passage has evolved to supply air to the phonic lips. It is thought that the nostrils of the land-based ancestor of the sperm whale migrated through evolution to their current functions, the left nostril becoming the blowhole and the right nostril becoming the phonic lips. Air that passes through the phonic lips passes into the distal sac, then back down through the left nasal passage. This recycling of air allows the whale to continuously generate clicks for as long as it is submerged.


Types of vocalization

A creak is a rapid series of high-frequency clicks that sounds somewhat like a creaky door hinge. It is typically used when homing in on prey. A coda is a short pattern of 3 to 20 clicks that is used in social situations. They were once thought to be a way by which individuals identified themselves, but individuals have been observed producing multiple codas, and the same codas are used by multiple individuals. Whitehead, p. 141 However, each click contains a physical signature which suggests that clicks can be used to identify individuals. Geographically separate pods exhibit distinct dialects. Whitehead, p. 131 Large males are generally solitary and rarely produce codas. In breeding grounds, codas are almost entirely produced by adult females. Despite evidence that sperm whales share similar codas, it is still unknown whether sperm whales possess individually specific coda repertoires or whether individuals make codas at different rates. Slow clicks are heard only in the presence of males (it is not certain whether females occasionally make them). Males make a lot of slow clicks in breeding grounds (74% of the time), both near the surface and at depth, which suggests they are primarily mating signals. Outside breeding grounds, slow clicks are rarely heard, and usually near the surface. Whitehead, p. 144


Ecology


Distribution

Sperm whales are among the most cosmopolitan species. They prefer ice-free waters over deep. Although both sexes range through temperate and tropical oceans and seas, only adult males populate higher
latitude In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north ...
s. Among several regions, such as along coastal waters of southern
Australia Australia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands. With an area of , Australia is the largest country by ...
, sperm whales have been considered to be locally extinct. They are relatively abundant from the poles to the equator and are found in all the oceans. They inhabit the
Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on ...
, but not the
Black Sea The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, Rom ...
, while their presence in the
Red Sea The Red Sea ( ar, البحر الأحمر - بحر القلزم, translit=Modern: al-Baḥr al-ʾAḥmar, Medieval: Baḥr al-Qulzum; or ; Coptic: ⲫⲓⲟⲙ ⲛ̀ϩⲁϩ ''Phiom Enhah'' or ⲫⲓⲟⲙ ⲛ̀ϣⲁⲣⲓ ''Phiom ǹšari''; ...
is uncertain. The shallow entrances to both the Black Sea and the Red Sea may account for their absence. The Black Sea's lower layers are also
anoxic The term anoxia means a total depletion in the level of oxygen, an extreme form of hypoxia or "low oxygen". The terms anoxia and hypoxia are used in various contexts: * Anoxic waters, sea water, fresh water or groundwater that are depleted of diss ...
and contain high concentrations of sulphur compounds such as hydrogen sulphide. The first ever sighting off the coast of
Pakistan Pakistan ( ur, ), officially the Islamic Republic of Pakistan ( ur, , label=none), is a country in South Asia. It is the world's List of countries and dependencies by population, fifth-most populous country, with a population of almost 24 ...
was made in 2017. The first ever record off the west coast of the Korean Peninsula (
Yellow Sea The Yellow Sea is a marginal sea of the Western Pacific Ocean located between mainland China and the Korean Peninsula, and can be considered the northwestern part of the East China Sea. It is one of four seas named after common colour ter ...
) was made in 2005. followed by one near Ganghwa Island in 2009. Populations are denser close to continental shelves and canyons. Sperm whales are usually found in deep, off-shore waters, but may be seen closer to shore, in areas where the continental shelf is small and drops quickly to depths of . Coastal areas with significant sperm whale populations include the
Azores ) , motto =( en, "Rather die free than subjected in peace") , anthem= ( en, "Anthem of the Azores") , image_map=Locator_map_of_Azores_in_EU.svg , map_alt=Location of the Azores within the European Union , map_caption=Location of the Azores wi ...
and
Dominica Dominica ( or ; Kalinago: ; french: Dominique; Dominican Creole French: ), officially the Commonwealth of Dominica, is an island country in the Caribbean. The capital, Roseau, is located on the western side of the island. It is geographical ...
. Whitehead, pp. 23–24 In east Asian waters, whales are also observed regularly in coastal waters in places such as the
Commander Commander (commonly abbreviated as Cmdr.) is a common naval officer rank. Commander is also used as a rank or title in other formal organizations, including several police forces. In several countries this naval rank is termed frigate captain. ...
and
Kuril Islands The Kuril Islands or Kurile Islands (; rus, Кури́льские острова́, r=Kuril'skiye ostrova, p=kʊˈrʲilʲskʲɪjə ɐstrɐˈva; Japanese language, Japanese: or ) are a volcanic archipelago currently administered as part of Sakh ...
, Shiretoko Peninsula which is one of few locations where sperm whales can be observed from shores, off Kinkasan, vicinity to
Tokyo Bay is a bay located in the southern Kantō region of Japan, and spans the coasts of Tokyo, Kanagawa Prefecture, and Chiba Prefecture. Tokyo Bay is connected to the Pacific Ocean by the Uraga Channel. The Tokyo Bay region is both the most populou ...
and the Bōsō Peninsula to the Izu and the Izu Islands, the Volcano Islands, Yakushima and the
Tokara Islands The is an archipelago in the Nansei Islands, and are part of the Satsunan Islands, which is in turn part of the Ryukyu Archipelago. The chain consists of twelve small islands located between Yakushima and Amami-Oshima. The islands have a total ...
to the
Ryukyu Islands The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Taiwan: the Ōsumi, Tokara, Amami, Okinawa, and Sakishima Islands (further divided into the Miyako and Yaeyama Islands), with Yon ...
,
Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia, at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the no ...
, the
Northern Mariana Islands The Northern Mariana Islands, officially the Commonwealth of the Northern Mariana Islands (CNMI; ch, Sankattan Siha Na Islas Mariånas; cal, Commonwealth Téél Falúw kka Efáng llól Marianas), is an unincorporated territory and commonw ...
, and so forth. Historical catch records suggest there could have been smaller aggression grounds in the
Sea of Japan The Sea of Japan is the marginal sea between the Japanese archipelago, Sakhalin, the Korean Peninsula, and the mainland of the Russian Far East. The Japanese archipelago separates the sea from the Pacific Ocean. Like the Mediterranean Sea, i ...
as well. Along the
Korean Peninsula Korea ( ko, 한국, or , ) is a peninsular region in East Asia. Since 1945, it has been divided at or near the 38th parallel, with North Korea (Democratic People's Republic of Korea) comprising its northern half and South Korea (Republic ...
, the first confirmed observation within the Sea of Japan, eight animals off Guryongpo, was made in 2004 since after the last catches of five whales off
Ulsan Ulsan (), officially the Ulsan Metropolitan City is South Korea's seventh-largest metropolitan city and the eighth-largest city overall, with a population of over 1.1 million inhabitants. It is located in the south-east of the country, neighboring ...
in 1911,우연과 인연. 2005
윗 글 향고래
Daum. Retrieved 7 October 2017
while nine whales were observed in the East China Sea side of the peninsula in 1999. Grown males are known to enter surprisingly shallow bays to rest (whales will be in a state of rest during these occasions). There are unique, coastal groups reported from various areas among the globe such as near the
Scotland Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to ...
's coastal waters, and Shiretoko Peninsula, off Kaikoura, in the Davao Gulf. Such coastal groups were more abundant in pre-whaling days. Genetic analysis indicates that the world population of sperm whales originated in the Pacific Ocean from a population of about 10,000 animals around 100,000 years ago, when expanding ice caps blocked off their access to other seas. In particular, colonization of the Atlantic was revealed to have occurred multiple times during this expansion of their range.


Diet

Sperm whales usually dive between , and sometimes , in search of food. Whitehead, p. 79 Such dives can last more than an hour. They feed on several species, notably the
giant squid The giant squid (''Architeuthis dux'') is a species of deep-ocean dwelling squid in the family Architeuthidae. It can grow to a tremendous size, offering an example of abyssal gigantism: recent estimates put the maximum size at around Tra ...
, but also the
colossal squid The colossal squid (''Mesonychoteuthis hamiltoni'') is part of the family Cranchiidae. It is sometimes called the Antarctic squid or giant cranch squid and is believed to be the largest squid species in terms of mass. It is the only recognize ...
, octopuses, and fish such as
demersal The demersal zone is the part of the sea or ocean (or deep lake) consisting of the part of the water column near to (and significantly affected by) the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer ...
ray Ray may refer to: Fish * Ray (fish), any cartilaginous fish of the superorder Batoidea * Ray (fish fin anatomy), a bony or horny spine on a fin Science and mathematics * Ray (geometry), half of a line proceeding from an initial point * Ray (gr ...
s and
shark Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachi ...
s, but their diet is mainly medium-sized squid. Whitehead, pp. 43–55 Some prey may be taken accidentally while eating other items. Most of what is known about deep-sea squid has been learned from specimens in captured sperm whale stomachs, although more recent studies analysed faeces. One study, carried out around the Galápagos, found that squid from the genera ''
Histioteuthis ''Histioteuthis'' is a genus of squid in the family Histioteuthidae. It goes by the common name cock-eyed squid, because in all species the right eye is normal-sized, round, blue and sunken; whereas the left eye is at least twice the diameter o ...
'' (62%), '' Ancistrocheirus'' (16%), and ''
Octopoteuthis ''Octopoteuthis'' is a genus of squid. It is one of two genera in the family Octopoteuthidae, the other being '' Taningia''. Both ''Octopoteuthis'' and ''Taningia'' are characterized by their lack of tentacles for the majority of their life cy ...
'' (7%) weighing between were the most commonly taken. Battles between sperm whales and giant squid or colossal squid have never been observed by humans; however, white scars are believed to be caused by the large squid. One study published in 2010 collected evidence that suggests that female sperm whales may collaborate when hunting Humboldt squid. Tagging studies have shown that sperm whales hunt upside down at the bottom of their deep dives. It is suggested that the whales can see the squid silhouetted above them against the dim surface light. An older study, examining whales captured by the New Zealand whaling fleet in the Cook Strait region, found a 1.69:1 ratio of squid to fish by weight. Sperm whales sometimes take sablefish and
toothfish ''Dissostichus'', the toothfish, is a genus of marine ray-finned fish belonging to the family Nototheniidae, the notothens or cod icefish. These fish are found in the Southern Hemisphere. Toothfish are marketed in the United States as Chilea ...
from long lines. Long-line fishing operations in the Gulf of Alaska complain that sperm whales take advantage of their fishing operations to eat desirable species straight off the line, sparing the whales the need to hunt. However, the amount of fish taken is very little compared to what the sperm whale needs per day. Video footage has been captured of a large male sperm whale "bouncing" a long line, to gain the fish. Sperm whales are believed to prey on the megamouth shark, a rare and large deep-sea species discovered in the 1970s. In one case, three sperm whales were observed attacking or playing with a megamouth. Sperm whales have also been noted to feed on bioluminescent pyrosomes such as '' Pyrosoma atlanticum''. It is thought that the foraging strategy of sperm whales for bioluminescent squids may also explain the presence of these light-emitting pyrosomes in the diet of the sperm whale. The sharp beak of a consumed squid lodged in the whale's intestine may lead to the production of ambergris, analogous to the production of
pearl A pearl is a hard, glistening object produced within the soft tissue (specifically the mantle) of a living shelled mollusk or another animal, such as fossil conulariids. Just like the shell of a mollusk, a pearl is composed of calcium carb ...
s in oysters. The irritation of the intestines caused by squid beaks stimulates the secretion of this lubricant-like substance. Sperm whales are prodigious feeders and eat around 3% of their
body weight Human body weight is a person's mass or weight. Strictly speaking, body weight is the measurement of weight without items located on the person. Practically though, body weight may be measured with clothes on, but without shoes or heavy accessor ...
per day. The total annual consumption of prey by sperm whales worldwide is estimated to be about . In comparison, human consumption of seafood is estimated to be . Sperm whales hunt through echolocation. Their clicks are among the most powerful sounds in the animal kingdom ( see above). It has been hypothesised that it can stun prey with its clicks. Experimental studies attempting to duplicate this effect have been unable to replicate the supposed injuries, casting doubt on this idea. One study showing that sound pressure levels on the squid are more than an order of magnitude below levels required for debilitation, and therefore, precluding acoustic stunning to facilitate prey capture. It has been stated that sperm whales, as well as other large cetaceans, help fertilise the surface of the ocean by consuming nutrients in the depths and transporting those nutrients to the oceans' surface when they defecate, an effect known as the
whale pump Whale feces, the excrement of whales, has a significant role in the ecology of the oceans, and whales have been referred to as "marine ecosystem engineers". Nitrogen released by cetacean species and iron chelate is a significant benefit to ...
. This fertilises phytoplankton and other plants on the surface of the ocean and contributes to ocean productivity and the drawdown of atmospheric carbon.


Life cycle

Sperm whales can live 70 years or more. They are a prime example of a species that has been K-selected, meaning their
reproductive strategy Reproduction (or procreation or breeding) is the biological process by which new individual organisms – "offspring" – are produced from their "parent" or parents. Reproduction is a fundamental feature of all known life; each individual org ...
is associated with stable environmental conditions and comprises a low birth rate, significant parental aid to offspring, slow maturation, and high longevity. How they choose mates has not been definitively determined. Bulls will fight with each other over females, and males will mate with multiple females, making them polygynous, but they do not dominate the group as in a harem. Whitehead, p. 276 Bulls do not provide paternal care to their offspring but rather play a fatherly role to younger bulls to show dominance. Whitehead, p. 343 Females become fertile at around 9 years of age. Whitehead, p. 122 The oldest pregnant female ever recorded was 41 years old. Whitehead, p. 123 Gestation requires 14 to 16 months, producing a single calf. Sexually mature females give birth once every 4 to 20 years (pregnancy rates were higher during the whaling era). Birth is a social event, as the mother and calf need others to protect them from predators. The other adults may jostle and bite the newborn in its first hours. Whitehead, p. 185
Lactation Lactation describes the secretion of milk from the mammary glands and the period of time that a mother lactates to feed her young. The process naturally occurs with all sexually mature female mammals, although it may predate mammals. The proces ...
proceeds for 19 to 42 months, but calves, rarely, may suckle up to 13 years. Like that of other whales, the sperm whale's milk has a higher fat content than that of terrestrial mammals: about 36%, compared to 4% in cow milk. This gives it a consistency similar to cottage cheese, which prevents it from dissolving in the water before the calf can drink it. It has an energy content of roughly 3,840 kcal/kg, compared to just 640 kcal/kg in cow milk. Calves may be allowed to suckle from females other than their mothers. Males become sexually mature at 18 years. Upon reaching sexual maturity, males move to higher
latitude In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north ...
s, where the water is colder and feeding is more productive. Females remain at lower latitudes. Males reach their full size at about age 50.


Social behaviour


Relations within the species

Like elephants, females and their young live in matriarchal groups called pods, while bulls live apart. Bulls sometimes form loose bachelor groups with other males of similar age and size. As they grow older, they typically live solitary lives, only returning to the pod to socialize or to breed. Bulls have beached themselves together, suggesting a degree of cooperation which is not yet fully understood. The whales rarely, if ever, leave their group. Whitehead, p. 232 A ''social unit'' is a group of sperm whales who live and travel together over a period of years. Individuals rarely, if ever, join or leave a social unit. There is a huge variance in the size of social units. They are most commonly between six and nine individuals in size but can have more than twenty. Whitehead, p. 233 Unlike
orca The orca or killer whale (''Orcinus orca'') is a toothed whale belonging to the oceanic dolphin family, of which it is the largest member. It is the only extant species in the genus '' Orcinus'' and is recognizable by its black-and-white ...
s, sperm whales within a social unit show no significant tendency to associate with their genetic relatives. Whitehead, p. 235 Females and calves spend about three-quarters of their time foraging and a quarter of their time socializing. Socializing usually takes place in the afternoon. Whitehead, p. 204 When sperm whales socialize, they emit complex patterns of clicks called codas. They will spend much of the time rubbing against each other. Tracking of diving whales suggests that groups engage in herding of prey, similar to bait balls created by other species, though the research needs to be confirmed by tracking the prey.


Relations with other species

The most common natural predator of sperm whales is the orca (killer whale), but
pilot whale Pilot whales are cetaceans belonging to the genus ''Globicephala''. The two extant species are the long-finned pilot whale (''G. melas'') and the short-finned pilot whale (''G. macrorhynchus''). The two are not readily distinguishable at sea, ...
s and false killer whales sometimes harass them. Orcas prey on target groups of females with young, usually making an effort to extract and kill a calf. The females will protect their calves or an injured adult by encircling them. They may face inwards with their tails out (the 'marguerite formation', named after the flower). The heavy and powerful tail of an adult whale is potentially capable of delivering lethal blows. Alternatively, they may face outwards (the 'heads-out formation'). Other than sperm whales, southern right whales had been observed to perform similar formations.Ponnampalam S.L., 2016
No Danger in Sight? An Observation of Sperm Whales (''Physeter macrocephalus'') in Marguerite Formation off Muscat, Sultanate of Oman
/ref> However, formations in non-dangerous situations have been recorded as well. Early whalers exploited this behaviour, attracting a whole unit by injuring one of its members. Such a tactic is described in '' Moby-Dick'':
"Say you strike a Forty-barrel-bull—poor devil! all his comrades quit him. But strike a member of the harem school, and her companions swim around her with every token of concern, sometimes lingering so near her and so long, as themselves to fall a prey."
If the killer whale pod is large, its members may sometimes be able to kill adult female sperm whales and can at least injure an entire pod of sperm whales. Bulls have no predators, and are believed to be too large, powerful and aggressive to be threatened by killer whales. Solitary bulls are known to interfere and come to the aid of vulnerable groups nearby. However, the bull sperm whale, when accompanying pods of female sperm whales and their calves as such, may be reportedly unable to effectively dissuade killer whales from their attacks on the group, although the killer whales may end the attack sooner when a bull is present.Whitehead, H. (2003). ''Sperm whales: social evolution in the ocean''. University of Chicago press. However, male sperm whales have been observed to attack and intimidate killer whale pods in competitive feeding instances. An incident was filmed from a long-line trawler: a killer whale pod was systematically taking fish caught on the trawler's long lines (as the lines were being pulled into the ship) when a male sperm whale appeared to repeatedly charge the killer whale pod in an attempt to drive them away; it was speculated by the film crew that the sperm whale was attempting to access the same fish. The killer whales employed a tail outward and tail-slapping defensive position against the bull sperm whale similar to that used by female sperm whales against attacking killer whales. However, at some potential feeding sites, the killer whales may prevail over sperm whales even when outnumbered by the sperm whales. Some authors consider the killer whales "usually" behaviorally dominant over sperm whales but express that the two species are "fairly evenly matched", with the killer whales' greater aggression, more considerable biting force for their size and predatory prowess more than compensating for their smaller size. Sperm whales are not known for forging bonds with other species, but it was observed that a bottlenose dolphin with a spinal deformity had been accepted into a pod of sperm whales. They are known to swim alongside other
cetaceans Cetacea (; , ) is an infraorder of aquatic mammals that includes whales, dolphins, and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively carnivorous diet. They propel th ...
such as humpback, fin, minke, pilot, and killer whales on occasion.


Parasites

Sperm whales can suffer from parasites. Out of 35 sperm whales caught during the 1976–1977 Antarctic whaling season, all of them were infected by '' Anisakis physeteris'' (in their stomachs) and '' Phyllobothrium delphini'' (in their blubber). Both whales with a placenta were infected with ''
Placentonema gigantissima ''Placentonema gigantissima'' is a giant nematode that parasitism, parasitizes the placenta of the sperm whale. With a length of and a diameter of , it is potentially the largest nematode worm ever described. It was discovered in the 1950s aroun ...
'', potentially the largest nematode worm ever described.


Evolutionary history


Fossil record

Although the fossil record is poor, several extinct genera have been assigned to the
clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English ter ...
Physeteroidea, which includes the last common ancestor of the modern sperm whale, pygmy sperm whales, dwarf sperm whales, and extinct physeteroids. These fossils include '' Ferecetotherium'', '' Idiorophus'', '' Diaphorocetus'', '' Aulophyseter'', ''
Orycterocetus ''Orycteocetus'' is an extinct genus of sperm whale from the Miocene of the northern Atlantic Ocean. Classification ''Orycterocetus'' is a member of Physeteroidea closely related to crown-group sperm whales. The type species, ''O. quadratidens'' ...
'', '' Scaldicetus'', '' Placoziphius'', '' Zygophyseter'' and '' Acrophyseter''. ''Ferecetotherium'', found in
Azerbaijan Azerbaijan (, ; az, Azərbaycan ), officially the Republic of Azerbaijan, , also sometimes officially called the Azerbaijan Republic is a transcontinental country located at the boundary of Eastern Europe and Western Asia. It is a part of th ...
and dated to the late
Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but t ...
(about ), is the most primitive fossil that has been found, which possesses sperm whale-specific features, such as an asymmetric rostrum ("beak" or "snout"). Most sperm whale fossils date from the
Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...
period, . ''Diaphorocetus'', from
Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the List of South American countries by area, second-largest ...
, has been dated to the early
Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...
. Fossil sperm whales from the Middle Miocene include ''Aulophyseter'', ''Idiorophus'' and ''Orycterocetus'', all of which were found on the West Coast of the United States, and ''Scaldicetus'', found in Europe and
Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the n ...
. ''Orycterocetus'' fossils have also been found in the North
Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...
and the
Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on ...
, in addition to the west coast of the United States. ''Placoziphius'', found in Europe, and ''Acrophyseter'', from
Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = National seal , national_motto = "Firm and Happy f ...
, are dated to the late Miocene. Fossil sperm whales differ from modern sperm whales in tooth count and the shape of the face and jaws. For example, ''Scaldicetus'' had a tapered rostrum. Genera from the Oligocene and early and middle Miocene, with the possible exception of ''Aulophyseter'', had teeth in their upper jaws. ''Acrophyseter'', from the late Miocene, also had teeth in both the upper and lower jaws as well as a short rostrum and an upward curving
mandible In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. It is the only movable bone ...
(lower jaw). These anatomical differences suggest that fossil species may not have necessarily been deep-sea squid eaters such as the modern sperm whale, but that some genera mainly ate fish. ''Zygophyseter'', dated from the middle to late Miocene and found in southern
Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...
, had teeth in both jaws and appears to have been adapted to feed on large prey, rather like the modern
killer whale The orca or killer whale (''Orcinus orca'') is a toothed whale belonging to the oceanic dolphin family, of which it is the largest member. It is the only extant species in the genus ''Orcinus'' and is recognizable by its black-and-white pat ...
(orca). Other fossil sperm whales with adaptations similar to this are collectively known as
killer sperm whale ''Zygophyseter varolai'' is an extinct sperm whale that lived during the Tortonian age of the Late Miocene 11.2 to 7.6 million years ago. It is known from a single specimen from the Pietra Leccese Formation in Italy. It was a member of a stem ...
s. Two poorly known fossil species belonging to the modern genus ''Physeter'' have been recognized so far: ''P. antiquus'' ( Neogene of France) and ''P. vetus'' (Neogene of eastern North America). ''Physeter vetus'' is very likely an invalid species, as the few teeth that were used to identify this species appear to be identical to those of another toothed whale, '' Orycterocetus quadratidens''.


Phylogeny

The traditional view has been that Mysticeti (baleen whales) and Odontoceti (toothed whales) arose from more primitive whales early in the
Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but t ...
period, and that the super-family Physeteroidea, which contains the sperm whale, dwarf sperm whale, and pygmy sperm whale, diverged from other toothed whales soon after that, over .Mchedlidze, G. "Sperm whales, evolution", pp. 1172–1174 in Perrin From 1993 to 1996,
molecular phylogenetics Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...
analyses by Milinkovitch and colleagues, based on comparing the genes of various modern whales, suggested that the sperm whales are more closely related to the
baleen whales Baleen whales ( systematic name Mysticeti), also known as whalebone whales, are a parvorder of carnivorous marine mammals of the infraorder Cetacea ( whales, dolphins and porpoises) which use keratinaceous baleen plates (or "whalebone") in t ...
than they are to other toothed whales, which would have meant that Odontoceti were not monophyletic; in other words, it did not consist of a single ancestral toothed whale species and all its descendants. However, more recent studies, based on various combinations of comparative anatomy and molecular phylogenetics, criticised Milinkovitch's analysis on technical grounds and reaffirmed that the Odontoceti are monophyletic. These analyses also confirm that there was a rapid evolutionary radiation (diversification) of the Physeteroidea in the
Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...
period. The
Kogiidae Kogiidae is a family comprising at least two extant species of Cetacea, the pygmy (''Kogia breviceps)'' and dwarf (''K. sima)'' sperm whales. As their common names suggest, they somewhat resemble sperm whales, with squared heads and small lowe ...
(dwarf and pygmy sperm whales) diverged from the Physeteridae (true sperm whales) at least . Whitehead, pp. 2–3


Relationship with humans


Sperm whaling

Spermaceti, obtained primarily from the spermaceti organ, and sperm oil, obtained primarily from the blubber in the body, were much sought after by 18th, 19th, and 20th century whalers. These substances found a variety of commercial applications, such as
candle A candle is an ignitable wick embedded in wax, or another flammable solid substance such as tallow, that provides light, and in some cases, a fragrance. A candle can also provide heat or a method of keeping time. A person who makes candle ...
s,
soap Soap is a salt of a fatty acid used in a variety of cleansing and lubricating products. In a domestic setting, soaps are surfactants usually used for washing, bathing, and other types of housekeeping. In industrial settings, soaps are us ...
,
cosmetics Cosmetics are constituted mixtures of chemical compounds derived from either natural sources, or synthetically created ones. Cosmetics have various purposes. Those designed for personal care and skin care can be used to cleanse or protec ...
, machine oil, other specialised lubricants, lamp oil, pencils, crayons, leather waterproofing, rust-proofing materials and many pharmaceutical compounds. Ambergris, a highly expensive, solid, waxy, flammable substance produced in the digestive system of sperm whales, was also sought as a fixative in perfumery. Prior to the early eighteenth century, hunting was mostly by indigenous Indonesians. Legend has it that sometime in the early 18th century, around 1712, Captain Christopher Hussey, while cruising for right whales near shore, was blown offshore by a northerly wind, where he encountered a sperm whale pod and killed one. Although the story may not be true, sperm whales were indeed soon exploited by American whalers. Judge Paul Dudley, in his ''Essay upon the Natural History of Whales'' (1725), states that a certain Atkins, 10 or 12 years in the trade, was among the first to catch sperm whales sometime around 1720 off the
New England New England is a region comprising six states in the Northeastern United States: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. It is bordered by the state of New York to the west and by the Canadian provinces ...
coast. There were only a few recorded instances during the first few decades (1709–1730s) of offshore sperm whaling. Instead, sloops concentrated on the
Nantucket Shoals Nantucket Shoals is an area of dangerously shallow water in the Atlantic Ocean that extends from Nantucket Island, Massachusetts, eastward for and southeastward for ; in places water depth can be as shallow as . Depth soundings are unpredictable ...
, where they would have taken right whales or went to the Davis Strait region to catch bowhead whales. By the early 1740s, with the advent of spermaceti candles (before 1743), American vessels began to focus on sperm whales. The diary of Benjamin Bangs (1721–1769) shows that, along with the bumpkin sloop he sailed, he found three other sloops flensing sperm whales off the coast of North Carolina in late May 1743. On returning to Nantucket in the summer 1744 on a subsequent voyage, he noted that "45 spermacetes are brought in here this day," another indication that American sperm whaling was in full swing. American sperm whaling soon spread from the east coast of the American colonies to the Gulf Stream, the
Grand Banks The Grand Banks of Newfoundland are a series of underwater plateaus south-east of the island of Newfoundland on the North American continental shelf. The Grand Banks are one of the world's richest fishing grounds, supporting Atlantic cod, sword ...
, West Africa (1763), the
Azores ) , motto =( en, "Rather die free than subjected in peace") , anthem= ( en, "Anthem of the Azores") , image_map=Locator_map_of_Azores_in_EU.svg , map_alt=Location of the Azores within the European Union , map_caption=Location of the Azores wi ...
(1765), and the South Atlantic (1770s). From 1770 to 1775 Massachusetts, New York, Connecticut, and Rhode Island ports produced 45,000 barrels of sperm oil annually, compared to 8,500 of whale oil. In the same decade, the British began sperm whaling, employing American ships and personnel. By the following decade, the French had entered the trade, also employing American expertise. Sperm whaling increased until the mid-nineteenth century. Spermaceti oil was important in public lighting (for example, in lighthouses, where it was used in the United States until 1862, when it was replaced by lard oil, in turn replaced by
petroleum Petroleum, also known as crude oil, or simply oil, is a naturally occurring yellowish-black liquid mixture of mainly hydrocarbons, and is found in geological formations. The name ''petroleum'' covers both naturally occurring unprocessed crud ...
) and for lubricating the machines (such as those used in cotton mills) of the
Industrial Revolution The Industrial Revolution was the transition to new manufacturing processes in Great Britain, continental Europe, and the United States, that occurred during the period from around 1760 to about 1820–1840. This transition included going f ...
. Sperm whaling declined in the second half of the nineteenth century, as petroleum came into broader use. In that sense, petroleum use may be said to have protected whale populations from even greater exploitation. Whitehead, pp. 13–21 Sperm whaling in the 18th century began with small sloops carrying only one or two whaleboats. The fleet's scope and size increased over time, and larger ships entered the fishery. In the late 18th century and early 19th century, sperm whaling ships sailed to the equatorial Pacific, the Indian Ocean, Japan, the coast of Arabia, Australia and New Zealand. Hunting could be dangerous to the crew, since sperm whales (especially bulls) will readily fight to defend themselves against attack, unlike most baleen whales. When dealing with a threat, sperm whales will use their huge head effectively as a battering ram. Arguably the most famous sperm whale counter-attack occurred on 20 November 1820, when a whale claimed to be about long rammed and sank the
Nantucket Nantucket () is an island about south from Cape Cod. Together with the small islands of Tuckernuck and Muskeget, it constitutes the Town and County of Nantucket, a combined county/town government that is part of the U.S. state of Massachuse ...
whaleship ''
Essex Essex () is a Ceremonial counties of England, county in the East of England. One of the home counties, it borders Suffolk and Cambridgeshire to the north, the North Sea to the east, Hertfordshire to the west, Kent across the estuary of the Riv ...
''. Only 8 out of 21 sailors survived to be rescued by other ships. The sperm whale's ivory-like teeth were often sought by 18th- and 19th-century whalers, who used them to produce inked carvings known as '' scrimshaw.'' 30 teeth of the sperm whale can be used for ivory. Each of these teeth, up to and across, are hollow for the first half of their length. Like walrus ivory, sperm whale ivory has two distinct layers. However, sperm whale ivory contains a much thicker inner layer. Though a widely practised art in the 19th century, scrimshaw using genuine sperm whale ivory declined substantially after the retirement of the whaling fleets in the 1880s. Modern whaling was more efficient than open-boat whaling, employing steam-powered ships and exploding
harpoon A harpoon is a long spear-like instrument and tool used in fishing, whaling, sealing, and other marine hunting to catch and injure large fish or marine mammals such as seals and whales. It accomplishes this task by impaling the target ani ...
s. Initially, modern whaling activity focused on large baleen whales, but as these populations were taken, sperm whaling increased. Spermaceti, the fine waxy oil produced by sperm whales, was in high demand. In both the 1941–1942 and 1942–1943 seasons, Norwegian expeditions took over 3,000 sperm whales off the coast of Peru alone. After
World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...
, whaling continued unabated to obtain oil for cosmetics and high-performance machinery, such as automobile transmissions. The hunting led to the near-extinction of large whales, including sperm whales, until bans on whale oil use were instituted in 1972. The International Whaling Commission gave the species full protection in 1985, but hunting by
Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the n ...
in the northern
Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the conti ...
continued until 1988. It is estimated that the historic worldwide population numbered 1,100,000 before commercial sperm whaling began in the early 18th century. By 1880, it had declined by an estimated 29 percent. From that date until 1946, the population appears to have partially recovered as whaling activity decreased, but after the Second World War, the population declined even further, to 33 per cent of the pre-whaling population. Between 184,000 and 236,000 sperm whales were killed by the various whaling nations in the 19th century, while in the 20th century, at least 770,000 were taken, the majority between 1946 and 1980. Sperm whales increase levels of primary production and carbon export by depositing iron-rich faeces into surface waters of the Southern Ocean. The iron-rich faeces cause phytoplankton to grow and take up more carbon from the atmosphere. When the phytoplankton dies, it sinks to the deep ocean and takes the atmospheric carbon with it. By reducing the abundance of sperm whales in the Southern Ocean, whaling has resulted in an extra 2 million tonnes of carbon remaining in the atmosphere each year. Remaining sperm whale populations are large enough that the species' conservation status is rated as vulnerable rather than endangered. However, the recovery from centuries of commercial whaling is a slow process, particularly in the
South Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...
, where the toll on breeding-age males was severe. Whitehead, pp. 360–362


Current conservation status

The total number of sperm whales in the world is unknown, but is thought to be in the hundreds of thousands. The conservation outlook is brighter than for many other whales. Commercial whaling has ceased, and the species is protected almost worldwide, though records indicate that in the 11-year period starting from 2000, Japanese vessels have caught 51 sperm whales. Fishermen do not target the creatures sperm whales eat, but long-line fishing operations in the Gulf of Alaska have complained about sperm whales stealing fish from their lines. Currently, entanglement in fishing nets and collisions with ships represent the greatest threats to the sperm whale population. Other threats include ingestion of marine debris, ocean noise, and chemical pollution. The
International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
(IUCN) regards the sperm whale as being " vulnerable". The species is listed as endangered on the United States Endangered Species Act. Sperm whales are listed on Appendix IAppendix I and Appendix II
of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). As amended by the Conference of the Parties in 1985, 1988, 1991, 1994, 1997, 1999, 2002, 2005 and 2008. Effective: 5 March 2009.
and Appendix II of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). It is listed on Appendix I as this species has been categorized as being in danger of extinction throughout all or a significant proportion of their range and CMS Parties strive towards strictly protecting these animals, conserving or restoring the places where they live, mitigating obstacles to migration and controlling other factors that might endanger them. It is listed on Appendix II as it has an unfavourable conservation status or would benefit significantly from international co-operation organised by tailored agreements. It is also covered by the Agreement on the Conservation of Cetaceans in the Black Sea, Mediterranean Sea and Contiguous Atlantic Area (ACCOBAMS) and the Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region (Pacific Cetaceans MOU). The species is protected under Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). This makes commercial international trade (including in parts and derivatives) prohibited, with all other international trade strictly regulated through a system of permits and certificates.


Cultural importance

Rope-mounted teeth are important cultural objects throughout the Pacific. In
New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island coun ...
, the
Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the Co ...
know them as "rei puta"; such whale tooth pendants were rare objects because sperm whales were not actively hunted in traditional
Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the Co ...
society. Whale ivory and bone were taken from beached whales. In
Fiji Fiji ( , ,; fj, Viti, ; Fiji Hindi: फ़िजी, ''Fijī''), officially the Republic of Fiji, is an island country in Melanesia, part of Oceania in the South Pacific Ocean. It lies about north-northeast of New Zealand. Fiji consis ...
the teeth are known as '' tabua'', traditionally given as gifts for atonement or esteem (called ''sevusevu''), and were important in negotiations between rival chiefs. Friedrich Ratzel in ''The History of Mankind'' reported in 1896 that, in Fiji, whales' or cachalots' teeth were the most-demanded article of ornament or value. They occurred often in necklaces. Today the tabua remains an important item in Fijian life. The teeth were originally rare in Fiji and Tonga, which exported teeth, but with the Europeans' arrival, teeth flooded the market and this "currency" collapsed. The oversupply led in turn to the development of the European art of scrimshaw.
Herman Melville Herman Melville ( born Melvill; August 1, 1819 – September 28, 1891) was an American novelist, short story writer, and poet of the American Renaissance period. Among his best-known works are '' Moby-Dick'' (1851); '' Typee'' (1846), a ...
's novel '' Moby-Dick'' is based on a true story about a sperm whale that attacked and sank the whaleship ''
Essex Essex () is a Ceremonial counties of England, county in the East of England. One of the home counties, it borders Suffolk and Cambridgeshire to the north, the North Sea to the east, Hertfordshire to the west, Kent across the estuary of the Riv ...
''. Melville associated the sperm whale with the Bible's Leviathan. The fearsome reputation perpetuated by Melville was based on bull whales' ability to fiercely defend themselves from attacks by early whalers, smashing whaling boats and, occasionally, attacking and destroying whaling ships. In Jules Verne's '' Twenty Thousand Leagues Under the Sea'', the Nautilus fights a group of "cachalots" (sperm whales) to protect a pod of southern right whales from their attacks. Verne portrays them as being savage hunters ("nothing but mouth and teeth"). The sperm whale was designated as the
Connecticut Connecticut () is the southernmost state in the New England region of the Northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, New York (state), New York to the west, and Long Island Sound to the ...
state animal by the
General Assembly A general assembly or general meeting is a meeting of all the members of an organization or shareholders of a company. Specific examples of general assembly include: Churches * General Assembly (presbyterian church), the highest court of pres ...
in 1975. It was selected because of its specific contribution to the state's history and because of its present-day plight as an endangered species.


Watching sperm whales

Sperm whales are not the easiest of whales to
watch A watch is a portable timepiece intended to be carried or worn by a person. It is designed to keep a consistent movement despite the motions caused by the person's activities. A wristwatch is designed to be worn around the wrist, attached ...
, due to their long dive times and ability to travel long distances underwater. However, due to the distinctive look and large size of the whale, watching is increasingly popular. Sperm whale watchers often use hydrophones to listen to the clicks of the whales and locate them before they surface. Popular locations for sperm whale watching include the town of Kaikoura on
New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island coun ...
's
South Island The South Island, also officially named , is the larger of the two major islands of New Zealand in surface area, the other being the smaller but more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman ...
, Andenes and
Tromsø Tromsø (, , ; se, Romsa ; fkv, Tromssa; sv, Tromsö) is a municipality in Troms og Finnmark county, Norway. The administrative centre of the municipality is the city of Tromsø. Tromsø lies in Northern Norway. The municipality is the ...
in Arctic
Norway Norway, officially the Kingdom of Norway, is a Nordic countries, Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of ...
; as well as the
Azores ) , motto =( en, "Rather die free than subjected in peace") , anthem= ( en, "Anthem of the Azores") , image_map=Locator_map_of_Azores_in_EU.svg , map_alt=Location of the Azores within the European Union , map_caption=Location of the Azores wi ...
, where the continental shelf is so narrow that whales can be observed from the shore, and
Dominica Dominica ( or ; Kalinago: ; french: Dominique; Dominican Creole French: ), officially the Commonwealth of Dominica, is an island country in the Caribbean. The capital, Roseau, is located on the western side of the island. It is geographical ...
where a long-term scientific research program, The Dominica Sperm Whale Project, has been in operation since 2005.


Plastic waste

The introduction of
plastic waste Plastic pollution is the accumulation of plastic objects and particles (e.g. plastic bottles, bags and microbeads) in the Earth's environment that adversely affects humans, wildlife and their habitat. Plastics that act as pollutants are catego ...
to the ocean environment by humans is relatively new. From the 1970s, sperm whales have occasionally been found with pieces of plastic in their stomachs.


See also

*
List of sperm whale strandings Strandings of sperm whale The sperm whale or cachalot (''Physeter macrocephalus'') is the largest of the toothed whales and the largest toothed predator. It is the only living member of the genus '' Physeter'' and one of three extant sp ...
* List of cetaceans * Marine biology


Notes


References


Further reading

* * * * Heptner, V. G.; Nasimovich, A. A; Bannikov, Andrei Grigorevich; Hoffmann, Robert S,
Mammals of the Soviet Union
', Volume II, part 3 (1996). Washington, D.C.: Smithsonian Institution Libraries and National Science Foundation


External links


The Dominica Sperm Whale Project
a long-term scientific research program focusing on the behaviour of sperm whale units.

22 July 2007
Society for Marine Mammalogy Sperm Whale Fact Sheet

70South
��information on the sperm whale
"Physty"-stranded sperm whale nursed back to health and released in 1981ARKive
��Photographs, video.
Whale Trackers
��An online documentary film exploring the sperm whales in the Mediterranean Sea.
Website of the Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands RegionOfficial website of the Agreement on the Conservation of Cetaceans in the Black Sea, Mediterranean Sea and Contiguous Atlantic Area

Retroposon analysis of major cetacean lineages: The monophyly of toothed whales and the paraphyly of river dolphins
19 June 2001
Sperm whales quickly learned to avoid humans who were hunting them in the 19th century, scientists say
ABC News ABC News is the news division of the American broadcast network ABC. Its flagship program is the daily evening newscast '' ABC World News Tonight with David Muir''; other programs include morning news-talk show '' Good Morning America'', '' ...
. 16 March 2021. {{Authority control Apex predators Mammals described in 1758 EDGE species Sperm whales Symbols of Connecticut Cosmopolitan mammals Articles containing video clips Animals that use echolocation Taxa named by Carl Linnaeus ESA endangered species