Species of large lamniform shark From Wikipedia, the free encyclopedia
The great white shark (Carcharodon carcharias), also known as the white shark, white pointer, or simply great white, is a species of large mackerel shark which can be found in the coastal surface waters of all the major oceans. It is the only known surviving species of its genus Carcharodon. The great white shark is notable for its size, with the largest preserved female specimen measuring 5.83 m (19.1 ft) in length and around 2,000 kg (4,400 lb) in weight at maturity.[5] However, most are smaller; males measure 3.4 to 4.0 m (11 to 13 ft), and females measure 4.6 to 4.9 m (15 to 16 ft) on average.[6][7] According to a 2014 study, the lifespan of great white sharks is estimated to be as long as 70 years or more, well above previous estimates,[8] making it one of the longest lived cartilaginous fishes currently known.[9] According to the same study, male great white sharks take 26 years to reach sexual maturity, while the females take 33 years to be ready to produce offspring.[10] Great white sharks can swim at speeds of 25 km/h (16 mph)[11] for short bursts and to depths of 1,200 m (3,900 ft).[12]
The great white shark is arguably the world's largest-known extant macropredatory fish, and is one of the primary predators of marine mammals, such as pinnipeds and dolphins. The great white shark is also known to prey upon a variety of other animals, including fish, other sharks, and seabirds. It has only one recorded natural predator, the orca.[13][14]
The species faces numerous ecological challenges which has resulted in international protection. The International Union for Conservation of Nature lists the great white shark as a vulnerable species,[2] and it is included in Appendix II of CITES.[15] It is also protected by several national governments, such as Australia (as of 2018).[16] Due to their need to travel long distances for seasonal migration and extremely demanding diet, it is not logistically feasible to keep great white sharks in captivity; because of this, while attempts have been made to do so in the past, there are no aquariums in the world known to house a live specimen.[17]
The great white shark is depicted in popular culture as a ferocious man-eater, largely as a result of the novel Jaws by Peter Benchley and its subsequent film adaptation by Steven Spielberg. While humans are not a preferred prey,[18] this species is nonetheless responsible for the largest number of reported and identified fatal unprovoked shark attacks on humans.[19] However, attacks are rare, typically occurring fewer than 10 times per year globally.[20][21]
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The most common English names for the species include 'great white shark', 'white shark', and Australian variant 'white pointer'.[22][23] These names are thought to refer to its white underside, which is noticeable in dead sharks lying upside down.[24] Colloquial use favours the name 'great white shark' or simply 'great white', with 'great' perhaps emphasizing the size and power of the species. Scientists typically use 'white shark', as there is no "lesser white shark" to be compared to,[25] though some use 'white shark' to refer to all members of the Lamnidae.[26]
The scientific genus name Carcharodon is a portmanteau of two Ancient Greek words: the prefix carchar- is derived from κάρχαρος (kárkharos), which means "sharp". The suffix -odon derives from ὀδών (odṓn), a which translates to "tooth". The specific name carcharias is from the καρχαρίας (karkharías), the Ancient Greek word for shark.[27][24] The great white shark was one of the species originally described by Carl Linnaeus in his 1758 10th edition of Systema Naturae and assigned the scientific name Squalus carcharias, Squalus being the genus that he placed all sharks in.[28] By the 1810s, it was recognized that the shark should be placed in a new genus, but it was not until 1838 when Sir Andrew Smith coined the name Carcharodon as the new genus.[29]
There have been a few attempts to describe and classify the white shark before Linnaeus. One of its earliest mentions in literature as a distinct type of animal appears in Pierre Belon's 1553 book De aquatilibus duo, cum eiconibus ad vivam ipsorum effigiem quoad ejus fieri potuit, ad amplissimum cardinalem Castilioneum. In it, he illustrated and described the shark under the name Canis carcharias based on the ragged nature of its teeth and its alleged similarities with dogs.[a] Another name used for the white shark around this time was Lamia, first coined by Guillaume Rondelet in his 1554 book Libri de Piscibus Marinis, who also identified it as the fish that swallowed the prophet Jonah in biblical texts.[30]
The white shark is the sole recognized extant species in the genus Carcharodon, and is one of five extant species belonging to the family Lamnidae.[27] Other members of this family include the mako sharks, porbeagle, and salmon shark. The family belongs to the Lamniformes, the order of mackerel sharks.[26]
The modern clade of the Lamnidae is estimated to have emerged between 65 and 46 million years ago (mya) based on a 1996 molecular clock using the mitochondrial DNA gene cytochrome b.[31] Most phylogenetic analyses based on molecular data or anatomical features place the great white shark as the sister species to the mako shark clade with the Lamna clade as the most basal in the family.[32][33] Under this topology, the 1996 clock estimated the great white shark's divergence from the makos to have occurred between 60 and 43 mya.[b][31] A more recent 2024 clock using genome-wide autosomal single nucleotide polymorphisms estimated a later alternate divergence between the shortfin mako and great white shark at 41.6 mya.[c][35] A minority of analyses recovered an alternate placement of the great white shark as the most basal member.[33] A 2025 clock using the whole mitogenome with this topology estimated the divergence between the great white shark and other lamnids at 47.4 mya.[36]
The great white shark first unambiguously appears in the fossil record in the Pacific basin about 5.3 mya at the beginning of the Pliocene.[1] Although there are few claims of fossils dated as early as 16 mya, their validity is doubted as mislabeled or misidentified.[d][37][38] Like all sharks, the great white's skeleton is made primarily of soft cartilage that does not preserve well. The overwhelming majority of fossils as a result are teeth.[39] Nevertheless, paleontologists have confidently traced the emergence of the great white shark and its immediate ancestry to a large extinct shark known as Carcharodon hastalis.[40] This species appeared worldwide during the Early Miocene (~23 mya) and had teeth alike to the modern great white shark's, except that the cutting edges lacked serrations.[37][38] The form was probably derived from an ancient lineage of large white sharks[41][42] that arose in the early Eocene (~56-48 mya) from a primitive mako-like shark.[41] C. hastalis occupied a middle to high trophic position in its ecosystems[43][44] and was probably piscivorous (fish-eating)[40][45] with some addition of marine mammals to its diet.[46]
Around 8 mya, a Pacific stock of C. hastalis evolved into C. hubbelli. This divergent lineage, sometimes described as a chronospecies,[37][40] was characterized by a gradual development of serrations over the next few million years. They were initially fine and sparse but a mosaic of fossils throughout the Pacific basin document an increase in quantity and coarseness over time,[40] eventually becoming fully serrated as the great white shark's by 5.3 mya.[1] Serrations are more effective at cutting prey than non-serrated edges, facilitating further specialization towards a mammal diet.[1][46] It is likely the ancestral unserrated stock had already been regularly targeting marine mammals for millions of years, and therefore maintained an environment favoring rapid selection towards increasingly serrated teeth once a mutation for incipient serrations appeared.[46] Teeth from the same strata may exhibit significant variation in serration development and morphology, which may be indicative of persistent interbreeding with C. hastalis for at least some time.[47] The great white shark dispersed as soon as it emerged, with fossils in the Mediterranean,[48] North Sea Basin,[49] and South Africa[50] occurring as early as 5.3-5 mya. Colonization of the northwestern Atlantic appeared to have delayed, with fossils absent until 3.3 mya.[51][52]
The great white shark has a stocky, torpedo-shaped body with a short, cone-shaped snout; long gill slits that do not reach around the head; a large triangular first dorsal fin, which partly lines up with the pectoral fins, and tiny second dorsal fin; a caudal fin with similarly sized lopes and one keel; and a tiny anal fin.[24][53] The species has a countershaded coloration; being dark on top, usually blue-gray or gray-brown, with a white underside. It also has black tips on the underside of the pectoral fins.[53][54] There is evidence that the species can change pigments, adding melanin to blotches of white.[55] The skin is covered in dermal denticles which are smaller than in other sharks, with a three ridged surface; each ridge having tips which point backwards.[56]
The great white shark is considered to be the largest macropredatory shark and fish.[57][58] Females are generally larger than males; the former measure on average 4.5–5 m (15–16 ft) in length while the latter average 3.5–4 m (11–13 ft) in length.[53] Similarly, females are recorded to weigh 1,000–1,900 kg (2,200–4,200 lb) compared to 680–1,000 kg (1,500–2,200 lb) for males.[59] The maximum size of the white shark has been debated. Its reputation has led to exaggerated and discredited claims of specimens up to 11.12 m (36.5 ft) during the 19th and 20th centuries.[60] Biologists Richard Ellis and John E. McCosker wrote that "These giants seem to disappear or shrink when a responsible observer approaches with tape measure".[61]
According to shark expert J. E. Randall, the largest white shark reliably measured was a 5.94 m (19.5 ft) specimen reported from Ledge Point, Western Australia in 1987.[62][5] He stated, "Undoubtedly Carcharodon carcharias exceeds 6.1 m (20 ft) in length, but as yet there is no authenticated record of such a size".[63] A 2014 study of white shark catch records in the northwest Pacific concluded that the longest reliably measured shark was 6.02 m (19.8 ft) in total length and the heaviest weighed 2,530 kg (5,580 lb).[64] A complete female great white shark specimen caught in the Mediterranean and displayed in the Museum of Zoology in Lausanne, Switzerland, measured 5.83 m (19.1 ft) in total body length with the caudal fin in its depressed position, and is estimated to have weighed 2,000 kg (4,410 lb) making it the largest preserved specimen.[5]
The triangular teeth are lined with serrations and can reach 7.5 cm (3.0 in).[65][66] They are broader on the upper jaw and overall more slender in juveniles.[67] The teeth are arranged in rows like a conveyor belt, with teeth in the back moving to replace those in front. An open mouth exposes roughly 26 and 24 front row teeth on the front row of the upper and lower jaw respectively, with a total of 300 teeth in the mouth.[66][68] The jaws are separate from the skull, and are connected to the body entirely by muscles and tendons; allowing them to project in and out.[69] The jaws can reach a gape of 150 degrees.[70]
A 2008 study using a computer scan of a 2.5 m (8.2 ft) long and 240 kg (530 lb) juvenile white shark determined that the specimen could exert a bite force of 1,602 newtons (360 lbf) in the front and 3,131 newtons (704 lbf) in the back. From this, the researchers deduced that a specimen 6.4 m (21 ft) long and massing 3,324 kg (7,328 lb) could exert a bite force of 9,320 newtons (2,100 lbf) in the front and 18,216 newtons (4,095 lbf) in the back.[71] The jaws are strengthened by mineralized cartilage; this is lacking in young white sharks which have to eat softer food.[72]
As with other sharks, white sharks use five senses when hunting; eyesight, hearing, olfaction (smell), electroreception (via pits called Ampullae of Lorenzini) and water movement detection (via a lateral line).[73][74] Analysis of the brain and cranial nerves suggest that sight and smell are the most developed.[73] The eyes of the white shark can appear solid black but have blue irises, and the pupil is more horizontal than in other species.[75][76] The eyes have a relatively low ratio of rods to cones, indicating daytime vision.[77] They lack nictitating membranes but possess well developed muscles that allow them to roll around to keep track of prey and roll back to avoid attacks.[77][78] The white shark has a relatively large olfactory bulb, an adaptation for smelling across open ocean;[79] it can detect potential prey from 110 m (360 ft).[80] The vomeronasal system, located in the roof of the mouth, also appears to play a role in olfactory sensing.[81] It's lateral line can detect disruptions in the water from 2 km (1.2 mi) away.[80]
The great white shark is an obligate ram ventilator; to breathe it must swim constantly so water flows through the gills.[82] Spiracles, extra breathing holes behind the eyes common in bottom dwelling sharks, is reduced or absent in this species.[83] It has a large, double-lobed, liver that can be almost 30% of its body weight, and stores lipids, fatty acids and oils.[84][85][86] The liver helps keep the shark from sinking, as the oil has six times the buoyancy of the surrounding water.[86] The lipids and fatty acids provide the shark energy for travel and fuel for reproduction and growth.[84][85] One study concluded that a white shark liver is more energy-rich than whale blubber.[85] White sharks appear to have strong immune systems and can tolerate high amounts of toxic heavy metals in their blood, moreso than other vertebrates.[87] They are also documented to heal relatively quickly from even serve wounds,[88] and the species' genome shows "positive selection in key genes involved in the wound-healing process...".[81]
Unlike most other fish, white sharks are endothermic ('warm-blooded').[89] Their bodies can maintain temperatures warmer than the surrounding water, which allows them to be active and hunt in cool waters. One study found that stomach temperatures ranged from 24.7–26.8 °C (76–80 °F) in waters 12.9–16.1 °C (55–61 °F).[90] White sharks maintain a warm body temperature via a complex blood vessel system known as a rete mirabile, were warm blood generated from the dark slow-twitch muscles is constantly supplied to other parts of the body within a countercurrent exchange system.[90][91] Heat is retained within the body rather than exiting via the gills.[92] Warm blood can also be redirected from the liver to the body core via a vascular shunt, which can open and close. In addition, the species has an enlarged, thickened heart and its blood contains more red-blood cells and hemoglobin than even most mammals and birds.[90]
Great white sharks range from tropical to temperate and even colder waters around the world,[24] with major populations in the northeastern Pacific, western North Atlantic, the Mediterranean, southern African waters, northwestern Pacific, Oceania and both the Pacific and Atlantic coasts of South America.[64][93] Shark expert Greg Skomal lists the Farallon Islands, California, Guadalupe Island, Mexico, Cape Cod, Massachusetts, Western Cape, South Africa, Neptune Islands, Australia, and both Stewart Island and the Chatham Islands, New Zealand as major coastal feeding aggregations.[94] Researchers have also identified an offshore feeding aggregation between western North America and Hawaii dubbed the White Shark Café.[95]
White sharks can be found both along the coast and in the open ocean, and may dive to depths of up to 1,300 m (4,300 ft) but are typically closer to the surface.[24][53] Deeper dives are more common in the open ocean.[96][97] Coastal habitats used include nearshore archipelagos, offshore reefs, banks and shoals, and headlands.[24] A 2018 study indicated that white sharks will congregate in anticyclonic eddies in the open ocean.[98] Juvenile white sharks are more limited to shallow coastal waters with temperatures between 14 and 24 °C (57 and 75 °F).[99] Increased observation of young sharks in areas they were not previously common, such as Monterey Bay on the central California coast, suggest climate change may be forcing juveniles towards the poles.[100]
White sharks go on vast migrations; one individual that was tagged off the South African coast swam to the southern coast of Australia and back within a year. Another white shark from South Africa was tracked and documented swimming to Australia's northwestern coast and back, a journey of 20,000 km (12,000 mi; 11,000 nmi) in under nine months.[96] In May 2024, a satellite tag was recovered from an Indonesian fisherman which was determined to have come from a subadult female great white shark tagged off the South African coast in May 2012 which swam to and got killed off the Indonesian coast in November 2016.[101]
In the northeastern Pacific, white sharks travel between the coastal US and Mexico and the Hawaiian Archipelago; they feed along the coast mostly during fall and winter, and farther out to sea during spring and summer.[102][103] In the western North Atlantic, white shark congregate between the Gulf of Maine and Cape Hatteras during spring and summer, and shift farther south towards Florida and around to the Gulf of Mexico during the fall and winter. In fall, winter and spring, some sharks disperse widely across the ocean, reaching as far east as the Azores.[97]
Great white sharks are more active during the daytime;[59] how they sleep is not well understood. At nighttime, one individual was recorded swimming slowly in one direction along a current with its mouth open.[104][105] White sharks typically swim at around 3.25 km/h (2.02 mph) but can sprint up to 50 km/h (31 mph).[59] One individual was recorded cruising at a sustained speed of 4.7 km/h (2.9 mph) while migrating, which is fast for a shark and more similar to fast-swimming tuna.[96] White sharks display various surface behaviors, such as poking its head out or spyhop to observe an object above the water, as well as 'Repetitive Aerial Gaping' where a spy-hopping shark repeatedly gaping its mouths while belly-up, possibly as a sign of frustration after missing a bait.[106]
The white shark is generally considered to be a solitary species, though aggregations do occur. A 2016 study of sharks around Mossel Bay, South Africa concluded that white shark associations are generally random with few social interactions.[107] By contrast, a 2019 study found that sharks around Neptune Islands gathered in non-random aggregations.[108] Similarly a 2022 study of white sharks at Guadalupe Island suggests that individuals may associate so that they can learn from others where to find prey or carcasses to scavenged.[109] White shark aggregations can also differ in composition of individuals based on age and sex. At Neptune Islands, sightings of subadult females peak during April and May, subadult males in February and again in September, adult females in June and adult males in September.[110]
The great white shark is an apex predator that opportunistically feeds on fish, cephalopods, marine mammals, sea birds and sea turtles. Diet differs based on size and age; individuals that have reached 3 m (9.8 ft) can feed on marine mammals, while juveniles are limited to smaller prey like fish and cephalopods.[111][59]
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Marine mammals preyed on include pinnipeds and cetaceans.[112] They are also recorded to bite sea otters but do not usually consume them.[113] The seasonal availability of pinnipeds drives white shark migration to certain locations.[114] Targeted species include harbor seals, northern elephant seals and California sea lions off western North America; harbor seals and gray seals off eastern North America; Cape fur seals off South Africa; Cape fur seals (Australian subspecies), New Zealand fur seals, and Australian sea lions off Australia; and New Zealand fur seals off New Zealand.[115][116] White sharks mainly hunt pinnipeds by ambush and often target newly weaned young as they have thick blubber but are still small, inexperienced and vulnerable.[117][118] Adults are more difficult to overpower and can injure the shark with their teeth and claws;[118] adult male elephant seals are particularly formidable as they can grow as massive as adult white sharks.[119][120] Some species will mob the shark.[121][122]
Observations off California find that white sharks ambush pinnipeds near the surface from below, seizing and dragging them under. Earless seals, like elephant seals, are more likely to be struck in front of the hind flippers or the head—even leading to decapitation—while sea lions were more likely to be grabbed behind the torso. With their large fore-flippers, sea lions are usually able to break free from the first bite but are weakened and usually recaptured. Prey is released after it dies of blood loss, and the shark feeds on the carcass after it floats to the surface.[120][123] In 1984, Tricas and McCosker suggested that white sharks bite pinnipeds, release them and then wait for them to bleed to death before eating,[124] though this has been refuted.[120] Off South Africa, ambushes on Cape fur seals usually involve the shark leaping or breaching out of the water.[122] To breach, a shark starts at around 20 m (66 ft) below the surface and ascends quickly towards its target, increasing its tail movements and pitch angle.[125] Sharks may breach partially or entirely out of the water at different angles, clearing up to 3 m (9.8 ft) when airborne. Missed seals may be chased after; such pursuits involve the prey using its speed and agility to escape as the shark employs various maneuvers to catch them. The longer the chase, the less likely the shark succeeds.[122] Sharks commonly consume fur seals quickly after they are killed.[126] White sharks in Cape Cod hunt seals in shallow water, relying on the murkiness of the water for concealment and striking them from the sides.[127]
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Cetacean species recorded as prey include small toothed whales like bottlenose dolphins, common dolphins, Indo-Pacific humpback dolphins, striped dolphins, Risso's dolphins and harbor porpoises.[128][129][130] Bite wounds from white sharks have also been documented on dusky dolphins, dwarf sperm whales, pygmy sperm whales and even beaked whales. White sharks typically attack them from behind—beyond the prey's echolocation—and target the tail, underside or dorsal area.[131] There are two records of white sharks managing to kill small humpback whales, one involved two sharks working as a pair. In both cases the whales were weakened by net entanglement, and the sharks employed strategic biting and as well as drowning.[132][133] White sharks are more likely to scavenge large whales. Multiple sharks will gorge themselves on a single whale carcass, biting into it and ripping off chunks by shaking their heads side-to-side. They may spit out pieces, possibly judging them to be too low in energy using their teeth as mechanoreceptors. The sharks do not appear to act aggressively towards each other, but accidental bites can occur. Eventually, the sharks become lethargic, they can no longer lift their heads out of the water nor can they get in a good bite as they bump into the dead whale.[134]
White sharks feed on numerous fish species, including other sharks.[112] One 2023 study found that juvenile and subadult white sharks off the east coast of Australia fed primarily on ray-finned fishes, particularly flathead grey mullets, Japanese scads and various species of porgies, mackrels and tuna.[135] Off California, white sharks will eat cobezons, white seabasses, lingcod, halibut, leopard sharks, smooth-hounds, spiny dogfishes, school sharks, stingrays, bat rays and skates.[136] In the Mediterranean, they consume Atlantic bluefin tunas, bullet tunas, Atlantic bonitos, swordfishes, blue sharks, shortfin makos and stingrays. An ocean sunfish was also recorded in a white shark stomach.[130] Off the northeastern US, juveniles commonly eat bottom-dwelling fish like hake, while off South Africa they often prey on dusky sharks.[114] The remains of an adult whale shark was found in a white shark, though whether this is active hunting or scavenging could not be determined.[137]
They are also recorded to consume cephalopods as evidenced by beaks found in their stomachs. Off South Africa, white sharks under 2.5 m (8.2 ft) were found with remains of coastal and bottom-dwelling species like certain octopus species, as well as species of the genera Sepia and Loligo, while sharks over that length seem to prefer more open ocean species like those of the genera Ancistrocheirus, Octopoteuthis, Lycoteuthis, Ornithoteuthis, Chiroteuthis and Argonauta.[138] Near Guadalupe, white sharks have been documented with scars which appear to have been caused by neon flying squids, jumbo squids and giant squids.[139] Both fish and cephalopods may be important food sources at the White Shark Café.[95]
Other animals recorded as prey include sea turtles. The shells of green sea turtles and loggerhead sea turtles have been found in white shark stomachs in the Mediterranean,[130] and bites have been recorded on leatherback sea turtles off central California.[140] Around Seal Island, South Africa, white sharks are recorded to attack and kill seabirds like Cape cormorants, kelp gulls, Cape gannets, brown skuas, African penguins, sooty shearwaters, and white breasted cormorants, but rarely consume them.[141]
Great white sharks communicate with each other through a complex array of body language. Most behaviors have been observed at aggregations around seal rookeries shortly after peak hunting periods, where sharks then engage in extensive socializing.[142] At least 20 unique forms of body language are known, most of which consist of two sharks swimming with or around each other in passing, parallel, or in circles to examine the other in a ritualized manner.[142][143] Occasionally one shark will openly show off its body in a lateral display to the other.[142] It is hypothesized that the main purpose of these interactions is to establish social rank by size to avoid competition.[142][143] Indeed, observations by Sperone and colleagues in 2010 found display behaviors to be more common between individuals of similar size where differences are not immediately obvious. There is no evidence that sex is a significant factor in behavioral patterns.[143] With dominance established, the smaller shark then acts submissively towards the larger shark by yielding during subsequent encounters or simply avoiding confrontation.[142][143] Body language is less frequent in California and Australia compared to Dyer Island in South Africa. It is thought that this is because the former locations are less densely populated, and so sharks there are more readily familiar with each other's hierarchy.[143]
Direct violence is extremely rare, as individuals typically end conflicts through peaceful means.[142] Splash fights appear to be the most common way of resolving ownership disputes over prey. Here, one shark slaps the surface with its tail to splash water at the competing shark. The competitor either withdraws or responds with a tail splash of its own. Usually one or two splashes are exchanged per shark, though individuals will sometimes persist with more.[144][145] The contest is "won" by the shark that compels the other to concede via the most tenacious splashing, which appears to be determined by a cumulative signal strength of vigor and strength. Larger body size does not always secure superior signal strength, on occasion the smaller shark emerges victorious. Great white sharks have also been observed employing tail splashing to intimidate tiger sharks around a whale carcass, and even against boats and shark cages which were likely perceived as competitors.[145]
Little is known of the reproductive behavior of the great white shark. There are two anecdotal accounts of the species possibly mating, one in 1991 and a second one in 1997, both off New Zealand. These testimonies both report belly to belly rolling during copulation. It is assumed that the male bites onto the female's head or fin while inserting one of his claspers, as is the case in other shark species. The accounts also suggest that that white sharks mate in shallow water away from feeding areas.[146][147] Females at Guadalupe and Cape Cod have been seen with scarring that may have been the result of copulation, possible evidence that these areas are used for mating.[148] Conversely other studies have concluded that white sharks may mate offshore; males were found to gather in the White Shark Café during spring and where followed by some females, suggesting a lek mating system where females move through and choose their partners.[149] In 2013, it was proposed that whale carcasses are an important location for sexually mature sharks to meet for mating.[134]
Some pregnant females have been caught and have provided information on the species' reproductive biology. The great white shark is ovoviviparous; fertilized eggs hatch within the female, and the embryos continue to develop within each uterus.[150] Their nourishment comes in three stages; they first feed on their yolk sacs, followed by a milky substance secreted by the uterus known as lipid histotrophy, and finally switch to consuming unfertilized eggs.[151][152] After around 12 months, the female gives live birth to two–to–ten pups. Birth intervals last two or three years.[53] A 2024 metastudy concluded that white sharks give birth during spring and summer in shallow waters surrounding islands with temperatures of 15.7 and 23.1 °C (60 and 74 °F).[93] White sharks are born at a length of 1–1.6 m (3.3–5.2 ft). In July 2024, a possible newborn white shark was filmed for the first time, off the coast of southern California (just off Carpinteria), measuring an estimated 1.5 m (4.9 ft) and with a pale complexion, originally attributed to histotrophy.[153] A follow-up study confirmed the Carpinteria shark being a newborn, but suggests that the paleness is embryonic epithelium that covers the shark's skin denticles, known to exist in the related salmon shark, and rubs off shortly after birth.[154]
Bands in the shark's vertebrate are used to determine the animal's age and growth. Early studies determined that the species grows relatively quickly; a 1985 study concluded that white sharks reach maturity nine to ten years of age at a length of 3.7–4.3 m (12–14 ft).[155] Conversely, a 2015 study concluded that white sharks are a slow growing and long lived species. Males were found to reach maturity at around 26 years at a length of around 3.5 m (11 ft) while females take 33 years to reach maturity at a length of around 4.5–5 m (15–16 ft). Their growth rate levels off after the age of 40 and their total lifespan is estimated to reach over 70 years.[156]
Great white sharks are sometimes preyed on by orcas, which they also likely compete with for food.[129] The first recorded orca predation occurred at the Farallon Islands in 1997 when an estimated 4.7–5.3 m (15–17 ft) female orca killed an estimated 3–4 m (9.8–13.1 ft) white shark.[158] Another similar attack apparently occurred there in 2000, but its outcome is not clear.[159] Subsequently, orca predation on white sharks would be documented off South Africa and Australia.[160][157] Around South Africa, orcas typically hunt white sharks in groups of two–to–six.[161] These cetaceans consume the energy-rich liver of the sharks[158] and dead white sharks washed ashore are found with these organs removed.[160][157] In 2017, a live white shark was seen with purported orca teeth marks, the first piece of evidence for the species surviving an attack.[162] The arrival of orcas in an area can cause white sharks to flee and forage elsewhere for the rest of the year, as has been documented both off South Africa and California.[157][163] In addition to orcas, white sharks may also fall prey to other sharks as pups and juveniles, including older white sharks.[93]
There are two recorded instances of the ectoparasitic cookiecutter shark targeting subadult white sharks off Guadalupe. However, the relative dearth of predation records indicates that white sharks are not a common food source for them.[164] The great white shark is the definitive host of two species of tapeworms from the genus Clistobothrium, these being Clistobothrium carcharodoni and Clistobothrium tumidum.[165][166] The former is believed to be transmitted to great whites through the consumption of infected cetacean prey which serve as intermediary or paratenic hosts of the tapeworm.[167] The latter species of tapeworm's transmission vector is currently unknown.[166] The intensity of C. carcharodoni infestations in affected great whites is extremely high; in one case, up to 2,533 specimens were recovered from the spiral intestine of a single individual.[167]
Prior to the 1970s, the great white shark as a species was known mostly to biologists and fishermen. The release of the 1971 documentary Blue Water, White Death is crediting with bringing the shark to public attention. The white shark's popularity would increase further with the 1974 novel Jaws written by Peter Benchley, and its 1975 film adaptation directed by Steven Spielberg.[168] The novel and film helped create the image of the species as a dangerous maneater. Benchley would later express regret stating "I cannot rewrite Jaws, nor make an ignoble monster of this magnificent animal.".[169]
Compared to other fish, the great white shark was not an important species for fishermen. Their meat was considered tasty but was it was not considered worth it due to the difficultly of hauling them in. Nevertheless, their reputation and size made them targets for sport fishing. The species was lured by chumming, and them presented with a hooked bait. Port Lincoln, South Australia was an epicenter of white shark fishing starting in the 1950s. In 1959, a fisherman named Alf Dean caught a 1,208 kg (2,663 lb) shark, and was given the record for being the largest fish caught by rod and reel. A larger white shark was caught in Streaky Bay but was disqualified based on the bait used.[170]
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Of all shark species, the great white shark is responsible for the largest number of recorded shark bite incidents on humans, with 351 documented unprovoked bite incidents on humans since 1580 as of 2024. The majority of them have been non-fatal, while 59 have been fatal.[20] White sharks do not appear to find humans suitable as prey, though cases of humans being consumed have been reported.[171]
In 1984, Tricas and McCosker proposed that white sharks attack humans out of mistaken identity; surfboards in particular may have a similar silhouette to seals and sea lions.[124] A 2021 study concludes that the sharks are likely colorblind and cannot see in fine enough detail to determine whether the silhouette above them is a pinniped or a swimming human, potentially vindicating the hypothesis.[172] Other studies have disputed the 'mistaken identity' hypothesis and have instead proposed that shark bites are actually exploratory bites. A 2016 study finds that most shark bites on surfers are too superficial to kill a pinniped and compares them to the test bites they make on different objects.[173] Similarly, a 2023 paper criticized the 'mistaken identity' hypothesis for focusing too much on vision and not considering the shark's other senses. The authors conclude that "sharks don't make 'mistakes' but instead continually explore their environments and routinely investigate novel objects as potential prey by biting them".[174]
Great white sharks infrequently bite boats. Tricas and McCosker's underwater observations suggest that sharks are attracted to boats by the electrical fields they generate, which are picked up by the ampullae of Lorenzini.[124]
The great white shark is difficult keep in captivity due to its large size and migratory nature.[175] Attempts had been made since 1955, in facilities in North America (and Hawaii), Australia and South Africa. The sharks survived only for days during the earliest attempts, while the early 1980s, aquariums like Steinhart Aquarium, Sea World San Diego, and Marineland of the Pacific were able to keep juvenile white sharks for weeks before releasing them.[176][177] A major contributor to the morality of captive white sharks was the poor transport; many were accidentally captured by commercial gillnets and kept on fishing lines or in a tank before being handed over to aquarium staff, causing them stress.[178] One famous shark named 'Sandy, who measured 2.3 m (7.5 ft), was kept at Steinhart for five days in August 1980 and was released for bumping into the walls.[177][179]
The most successful attempts at keeping the species occurred at the Monterey Bay Aquarium (MBA), where six white sharks were displayed between 2004 and 2011.[176] Researchers at universities in California attributed the aquarium's success at exhibiting white sharks to the use of a 4-million-US-gallon (15,000,000 L) net pen, which gave the sharks time to recover from capture prior to transport. A 3,200-US-gallon (12,000 L) portable tank used to transport the fish to the exhibit allowed the sharks to swim continuously.[180][181] The sharks started at 1.4–1.6 m (4.6–5.2 ft) but grew too big and had to be released;[182] one shark was kept for 198 days and attracted one million visitors.[180] Having gained enough information on the species, MBA discontinued keeping white sharks.[182]
Areas were white sharks gather have been sites for ecotourism; operators allow guests to view them from boats or from inside shark cages. Most operators allow chumming to attract the sharks. Cited benefits of ecotours include education, funding for research and increasing the value of living sharks.[183] One study in southern Australia found that shark tours had positive effects on the participants knowledge and awareness of the animals and support for their conservation.[184]
There is some fear that interactions with tourists could affect the sharks' behavior. At Neptune Islands, it was found that white sharks used more energy during encounters with cage divers. The researchers note, however, that cage-diving can have a minimal effect on shark populations as long as they limit interactions with individual sharks.[185] In the same area, excessive boats drove away many sharks, though the implementation in 2012 of new regulations on the number of licensed boat operators and number of operating days per week allowed for the population to recover.[186] There is also no strong evidence that chumming alters the feeding behavior of white sharks or habituates them to being fed by humans.[187][188][189] In January 2023, the Mexican government banned white shark tourism at Guadalupe; due to reports of swimming outside cages, mishandling chum, littering and two incidents of sharks getting stuck and harmed by the cages, one of which may have resulted in death.[190]
As of 2025, the great white shark is classified as vulnerable worldwide by the International Union for Conservation of Nature (IUCN), due to a population decline of 30–49% over the past 159 years. It was also given a green status of "moderately depleted" with a recovery score of 59%. The biggest threat to white shark populations is accidental catching in fishing nets and, in Australia and South Africa, beach protection programs, where are caught in protective drum-lines and gillnets. They nevertheless have a high survival rate when released from nets.[2] The species is included in Appendix II of CITES,[15] meaning that international trade in the species (including parts and derivatives) requires a permit.[191] The great white shark is also considered to be critically endangered in Europe[3] and the Mediterranean.[192]
The species has been protected in South Africa since 1991; the law bans both deliberate killing and selling.[193] The province of KwaZulu-Natal, via the KwaZulu-Natal Sharks Board (KZN), allows for the use of nets around protected beaches to reduce the risk of shark attacks but not at major aggregation sights.[194] A 1996 study estimated the average population size between 1989 and 1993 to be 1,279, while a 2004 estimated 1,953 individuals post-protection.[195][196] A 2023 study concluded that white shark numbers off South Africa have remained stable since 1991. While sightings of sharks at major aggregations sights in Western Cape have declined since the early 2010s, the researchers have attributed this to shifting their distribution further east, possibly in response to attacks by orcas.[197] The results of this study are disputed; in 2024 it was noted that catches of white sharks in KZN have declined since 2010, suggesting they have not moved eastward.[195]
The great white shark was declared vulnerable by the Australian Government in 1999 because of significant population decline and is currently protected under the Environmental Protection and Biodiversity Conservation (EPBC) Act.[198] The causes of decline prior to protection included mortality from sport fishing harvests as well as being caught in beach protection netting.[199]
The national conservation status of the great white shark is reflected by all Australian states under their respective laws, granting the species full protection throughout Australia regardless of jurisdiction.[198] Many states had prohibited the killing or possession of great white sharks prior to national legislation coming into effect. The great white shark is further listed as threatened in Victoria under the Flora and Fauna Guarantee Act, and as rare or likely to become extinct under Schedule 5 of the Wildlife Conservation Act in Western Australia.[198]
In 2002, the Australian government created the White Shark Recovery Plan, implementing government-mandated conservation research and monitoring for conservation in addition to federal protection and stronger regulation of shark-related trade and tourism activities.[199] An updated recovery plan was published in 2013 to review progress, research findings, and to implement further conservation actions.[16] A study in 2012 revealed that Australia's white shark population was separated by Bass Strait into genetically distinct eastern and western populations, indicating a need for the development of regional conservation strategies.[200]
Presently, human-caused shark mortality is continuing, primarily from accidental and illegal catching in commercial and recreational fishing as well as from being caught in beach protection netting, and the populations of great white shark in Australia are yet to recover.[16]
In spite of official protections in Australia, great white sharks continue to be killed in state "shark control" programs within Australia. For example, the government of Queensland has a "shark control" program (shark culling) which kills great white sharks (as well as other marine life) using shark nets and drum lines with baited hooks.[201][202] In Queensland, great white sharks that are found alive on the baited hooks are shot.[203] The government of New South Wales also kills great white sharks in its "shark control" program.[202] Partly because of these programs, shark numbers in eastern Australia have decreased.[204]
The Australasian population of great white sharks is believed to be in excess of 8,000–10,000 individuals according to genetic research studies done by CSIRO, with an adult population estimated to be around 2,210 individuals in both Eastern and Western Australia. The annual survival rate for juveniles in these two separate populations was estimated in the same study to be close to 73 per cent, while adult sharks had a 93 per cent annual survival rate. Whether or not mortality rates in great white sharks have declined, or the population has increased as a result of the protection of this species in Australian waters is as yet unknown due to the slow growth rates of this species.[205]
The great white shark is one of the most commonly found in the waters of New Zealand.[206] As of April 2007, great white sharks were fully protected within 370 km (230 mi) of New Zealand and additionally from fishing by New Zealand-flagged boats outside this range. The maximum penalty is a $250,000 fine and up to six months in prison.[207] In June 2018 the New Zealand Department of Conservation classified the great white shark under the New Zealand Threat Classification System as "Nationally Endangered". The species meets the criteria for this classification as there exists a moderate, stable population of between 1000 and 5000 mature individuals. This classification has the qualifiers "Data Poor" and "Threatened Overseas".[208]
In addition to existing federal regulations, great white sharks have been protected under California state law since January 1, 1994.[209] Under this law, catching, hunting, pursuit, capturing, and/or killing of great whites in California waters is strictly prohibited up to 3 miles (4.8 km) offshore,[210][211] though exceptions exist for great whites caught for scientific research or unintentionally caught as bycatch. In both cases, a special permit is required in order to legally take them.[212]
In 2013, great white sharks were added to California's Endangered Species Act. From data collected, the population of great whites in the North Pacific was estimated to be fewer than 340 individuals. Research also reveals these sharks are genetically distinct from other members of their species elsewhere in Africa, Australia, and the east coast of North America, having been isolated from other populations.[212]
A 2014 study estimated the population of great white sharks along the California coastline to be approximately 2,400.[213][214]
In September 2019, California governor Gavin Newsom signed Assembly Bill 2109 into law, banning the use of shark bait, shark lures, and chumming to attract great whites in California waters, and prohibiting their usage within one nautical mile of any shoreline, pier, or jetty when a great white is visible or known to be present in the area.[215][216]
In June 2015, Massachusetts banned catching, cage diving, feeding, towing decoys, or baiting and chumming for its significant and highly predictable migratory great white population without an appropriate research permit. However, these restrictions apply to only activities within state waters, which extend three miles from shore. Therefore, there are over a dozen tour operators offering cage diving and some do bait and/or chum.[11]
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