| Common names: shark (English), jaquetón (Espanol), tiburón (Espanol) |
Carcharodon carcharias (Linnaeus, 1758)
White shark, Great white shark
Fusiform, robust body; snout conical, blunt, with nostrils on sides; mouth large, round; teeth on top jaw triangular, serrated; 5 large gill slits, all before pectoral fin; first dorsal fin large, triangular, origin over rear of base of pectoral fin; second dorsal fin very small; anal fin very small, origin under rear of base of second dorsal fin; tail almost symmetrical, half-moon shaped; tail base very depressed, with large keel that extends onto tail itself.
Back grey-brown, blue-grey, to blackish; abrupt changing to white/pale grey belly; eye black; underside of tips of fins black, usually a black spot where rear edge of fin joins body.
Size: reaches ~ 600 cm.
Habitat: coastal, inshore to oceanic.
Depth: 0 to 1280 m.
Circumglobal, temperate; in our area: Baja and the Gulf of California; Panama to Chile and the Galapagos and Revillagigedos.
Description of Carcharodon carcharias
Global Endemism: All species, TEP non-endemic, Circumtropical ( Indian + Pacific + Atlantic Oceans), "Transpacific" (East + Central &/or West Pacific), All Pacific (West + Central + East), East Pacific + Atlantic (East +/or West), Transisthmian (East Pacific + Atlantic of Central America), East Pacific + all Atlantic (East+West)
Regional Endemism: All species, Eastern Pacific non-endemic, Tropical Eastern Pacific (TEP) non-endemic, Temperate Eastern Pacific, primarily, California + Peruvian provinces, primarily, Continent + Island (s), Continent, Island (s)
Climate Zone: North Temperate (Californian Province &/or Northern Gulf of California), Northern Subtropical (Cortez Province + Sinaloan Gap), Equatorial (Costa Rica to Ecuador + Galapagos, Clipperton, Cocos, Malpelo), South Temperate (Peruvian Province ), Antitropical (North and South temperate)
The geographic range of great white sharks is extremely wide. From 60°N latitude to 60°S latitude, they can be found in all cold temperate and tropical coastal waters. Great white sharks can be found in coastal waters along central California and off the western cape of South Africa. They have also been reported in North American coastal waters from Newfoundland to Florida and from Alaska to Southern Mexico (MarineBio, 2009). According to National Geographic Society (2009), there are no reliable data on great white shark population numbers.
Biogeographic Regions: indian ocean (Native ); atlantic ocean (Native ); pacific ocean (Native )
Other Geographic Terms: cosmopolitan
- 2009. "MarineBio" (On-line). Carcharodon carcharias: Great White Shark. Accessed April 02, 2009 at http://marinebio.org/species.asp?id=38.
- National Geographic Society. 2009. "Great White Shark: Carcharodon carcharias" (On-line). National Geographic. Accessed April 06, 2009 at http://animals.nationalgeographic.com/animals/fish/great-white-shark.html.
Great White Sharks also occur, albeit less frequently, at many sites elsewhere (e.g., Brazil, Caribbean, Azores, Hawaii, north-west Africa, east Africa (Kenya, Tanzania), Seychelles, Mauritius, Madagascar, Sri Lanka, northern Australia, New Caledonia and Philippines). Limited inter-hemispherical movement between temperate areas, across equatorial waters by means of tropical submergence has been suspected (Last and Stevens 1994), but more recently Great White Sharks have been found in tropical inshore waters of east and southern Africa and even sighted and photographed by divers on coral reefs in Mozambique and elsewhere (Cliff et al. 2000, Compagno 2001).
Regularity: Regularly occurring
Type of Residency: Year-round
Regularity: Regularly occurring
Type of Residency: Year-round
These massive predators reach lengths of 6 m long and weigh up to 3000 kg (McGouther, 2008). Female great white sharks tend to be larger than male great white sharks, who only reach lengths of approximately 4 m (Compagno, Dando and Fowler, 2005). The massive bodies of great white sharks are streamlined and powerful to generate bursts of speed. Their snouts are narrowed and somewhat pointed, and their eyes are onyx in color. These white bellied sharks have crescent shaped tails with long, nearly-symmetrical upper and lower lobes. The color of the dorsal side varies, dark gray to light gray. Great white sharks have a caudal fin and paired dorsal and pectoral fins that help to propel them through the water. The mouths of great white sharks are 0.9 to 1.2 m wide and the upper and bottom teeth work together when handling prey with the bottom teeth keeping the prey in place while the upper teeth tear into the flesh. Great white sharks are endothermic, generating body heat through metabolism (MarineBio, 2009).
Range mass: 3000 (high) kg.
Range length: 4 to 7 m.
Other Physical Features: endothermic ; bilateral symmetry
Sexual Dimorphism: female larger
- 2008. "Great White Shark: Predator of the Deep" (On-line). Great White Shark 101. Accessed April 03, 2009 at http://greatwhite.org/frame_facts.htm.
- Compagno, L., M. Dando, S. Fowler. 2005. Sharks of the World. Princeton, New Jersey: Princeton University Press.
- McGrouther, M. 2008. "Australian Museum" (On-line). Accessed April 02, 2009 at http://www.austmus.gov.au/fishes/fishfacts/fish/ccarchar.htm.
Inshore/Offshore: Offshore, In & Offshore, Inshore
Water Column Position: Surface, Near Surface, Mid Water, Near Bottom, Water column only
Habitat: Reef associated (reef + edges-water column & soft bottom), Water column
FishBase Habitat: Pelagic
Great white sharks are primarily a coastal and offshore inhabitant of insular and continental shelves (Aidan Martin, 2003). Great white sharks have been known to breach the surface and have also been found at depths of 1,875 meters (Dale, 2008). They seem to prefer waters with sea surface temperatures of 59 to 72°F (Aidan Martin, 2003). They can be found on the following coastlines: California to Alaska, the east coast of the United States, coastal Gulf of Mexico, Hawaii, coasts of South America, South Africa, Australia (except the north coast), New Zealand, Mediterranean Sea, West Africa to Scandinavia, Japan, and the eastern coastline of China to Russia (Dale, 2008).
Range depth: 0 to 1,875m m.
Habitat Regions: temperate ; tropical ; saltwater or marine
Aquatic Biomes: coastal
- Aidan Martin, R. 2003. "Brief Overview of the Great White Shark" (On-line). Biology of Sharks and Rays. Accessed April 06, 2009 at http://www.elasmo-research.org/education/white_shark/overview.htm.
- Dale, R. 2008. "OceanLink" (On-line). Great White Shark. Accessed April 06, 2009 at http://oceanlink.island.net/biodiversity/shark/shark.html#Anchor-Habitat.
Habitat and Ecology
Great White Sharks take a variety of bony fish as prey, from sedentary demersal rockfish, lingcod and benthic flatfish to fast pelagic species, and ranging in size from small demersal and schooling fishes to giants such as broadbill swordfish and bluefin tuna. Great White Sharks are known to congregate at concentrations of schooling bony fishes such as pilchards and bluefish, and follow the KwaZulu-Natal sardine run off South Africa (Compagno 2001). A broad range of elasmobranchs - sharks and batoids - are eaten by Great White Sharks, as are chimaeroids, chelonians, cephalopods and other molluscs, crustaceans and occasionally sea birds such as cormorants and penguins (Compagno 2001). The role of C. carcharias as a primary predator upon marine mammals and especially pinnipeds (e.g., northern elephant seals, harbour seals, California sealions, fur seals), has dominated much contemporary study of this species due to accessibility and intensive studies of seal colonies and a focus on seal predation as being related to biting of humans by great white sharks. The global importance of pinnipeds as prey taxa may be overstated, due to the regional bias in contemporary field observation towards those areas where sharks and pinnipeds are sympatric. Great White Sharks (especially larger individuals) are also active hunters of small odontocetes, particularly so (but not exclusively) in regions where pinnipeds are scarce or absent. Dead baleen whales and other large cetaceans may contribute a significant amount to the Great White Shark's diet in some areas (Long and Jones 1996), but such food is sporadically available.
Habitat Type: Marine
Water temperature and chemistry ranges based on 2 samples.
Depth range (m): 0 - 516
Temperature range (°C): 11.444 - 19.831
Nitrate (umol/L): 1.911 - 3.346
Salinity (PPS): 33.402 - 35.345
Oxygen (ml/l): 4.943 - 6.250
Phosphate (umol/l): 0.477 - 0.495
Silicate (umol/l): 2.312 - 6.500
Depth range (m): 0 - 516
Temperature range (°C): 11.444 - 19.831
Nitrate (umol/L): 1.911 - 3.346
Salinity (PPS): 33.402 - 35.345
Oxygen (ml/l): 4.943 - 6.250
Phosphate (umol/l): 0.477 - 0.495
Silicate (umol/l): 2.312 - 6.500
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.
Recorded at 1280 meters.
Habitat: pelagic. Great white shark. (Linnaeus, 1758) A huge, spindle shaped shark with small conspicuous black eyes; a blunt, conical snout and large, triangular, saw-edged teeth. Colour lead-grey to brown or black above, lighter on sides and abruptly white below; black spot at rear pectoral fin base. Attains up to 7,1 metres TL. A swift, active, powerful shark that can leap out of the water. Eats bony fish, sharks, rays, seals, dolphins and porpoises, sea birds, carrion, squid, octopus and crabs. Bears 7 to 9 young. Found in all temperate and tropical seas from the surface down to 1280 metres. A potentially very dangerous species that infrequently attacks swimmers, divers, surfers and boats; frequently investigates divers and boats without attacking. An endangered species that is now being protected in South African waters.
Non-Migrant: No. All populations of this species make significant seasonal migrations.
Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).
Locally Migrant: No. No populations of this species make annual migrations of over 200 km.
Diet: mobile benthic crustacea (shrimps/crabs), octopus/squid/cuttlefish, bony fishes, sharks/rays, sea snakes/mammals/turtles/birds
Young great white sharks typically feed on smaller species such as squid and stingrays, as well as other small sharks (McGrouther, 2008). As these fish mature their appetites change. The diet of adults consists primarily of seals, sealions, dolphins, and whale carcasses (McGrouther, 2008). One of the most frequent prey animals of great white sharks are elephant seals (MarineBio, 2009). Sometimes they feed on turtles and various sea birds (McGrouther, 2008). Great white sharks may attack with different strategies depending on the size of their prey. The most common attack method used by great white sharks involves the shark positioning itself directly below its prey and then swimming vertically into an attack (MarineBio, 2009). These sharks collide into their prey and then bite them. Prey often die from blood loss, decapitation or severance of vital appendages such as fins. Great white sharks have been reported to attack humans but there have been as few as 311 verified deaths from great white shark attacks (Burnie and Wilson, 2001).
Animal Foods: birds; mammals; reptiles; fish; mollusks; other marine invertebrates
Primary Diet: carnivore (Eats terrestrial vertebrates, Piscivore , Molluscivore )
Great white sharks are apex predators, meaning they have a large affect on the populations of their prey including elephant seals and sea lions. Great white sharks are hosts to parasites such as copepods (Pandarus sinuatus and Pandarus smithii).
- Pandarus sinuatus
- Pandarus smithii
Great white sharks are apex predators; they are at the top of the food chain. Occasionally great white sharks will encounter a killer whale or another shark of comparable size (Martins and Knickle, 2009). These species pose a small threat to great white sharks.
- Martins, C., C. Knickle. 2009. "Florida Museum of Natural History" (On-line). Accessed April 08, 2009 at http://www.flmnh.ufl.edu/fish/Gallery/Descript/Whiteshark/whiteshark.html.
Known prey organisms
This list may not be complete but is based on published studies.
Life History and Behavior
Sharks have several highly developed senses. Their primary sense is the ability to smell. They can detect a drop of blood in 100 liters of water. They also have the ability to detect electrical charges as small as 0.005 microvolts. Prey can be detected by the electrical field generated by a beating heart or gill action. Fish in hiding can also be detected this way. At feeding aggregations, such as at whale carcasses, this generally solitary species often establishes temporary social hierarchies which are based largely on size. Among similar-sized individuals, the social hierarchy is maintained through a subtle form of body language. Recent research has demonstrated that great whites are socially complex, featuring such behaviors as parallel swimming, jaw gaping, pectoral fin depression, and even splash-fights. Great white sharks are also unusual among sharks in that they sometime rais their heads out of the water, apparently to observe activity above the surface.
Communication Channels: visual ; tactile ; chemical ; electric
Perception Channels: visual ; tactile ; chemical ; electric
There is not a lot of information about the development of great white sharks. While great white sharks develop in the uterus of the mother shark they eat other embryos and unfertilized eggs (Burnie and Wilson, 2001). When great white sharks are born they are approximately 1 to 1.5 meters in length. Around the age of 10 years, male great white sharks have matured to a length of about 4 meters. Females, on the other hand, mature later, around the age of 15 years, at a length of 4 to 5 meters (MarineBio, 2009).
- Burnie, D., D. Wilson. 2001. Smithsonian Institution Animal: The Definitive Visual Guide to the World's Wildlife. New York, New York: Dorling Kindersley.
The age of great white sharks can be determined by counting the rings that form on the vertebra. It is believed that great white sharks breed between the ages of 9 and 23 years old and that their lifespan is approximately 30 years (Levine, 1998). Various research indicates that great white sharks live somewhere between 30 and 40 years (Shark Information, 2009).
Status: wild: 30 years.
Status: wild: 30 years.
- Levine, M. 1998. Great White Sharks. Weigl Educational Publishers. Accessed April 06, 2009 at http://books.google.com/books?id=T0pKBTypGBQC.
Lifespan, longevity, and ageing
Much about the mating behavior of great white sharks is still unknown. Some scientists believe that scarred individuals suggest male-male aggression or that a male’s gentle biting of females may precede mating. Bite marks observed on the dorsum, flanks, and particularly the pectoral fins of mature female great whites have been interpreted as the results of mating. It is most likely that the male bites the female during copulation. Great white sharks have also been known to propel two-thirds of their body out of the water and land flat against the surface, causing a large splash. This behavior is called a "pattern breach". This behavior might be used to attract a mate during courtship. Mating has yet to be fully documented in great white sharks, but it is assumed to be similar to internal fertilization in most sharks, where the male inserts his claspers into the cloaca of the female. Courtship behavior, if there is any, is unknown.
Mating System: polygynandrous (promiscuous)
Reproduction is ovoviviparous, that is, fertilized eggs are retained within the body and develop there. Prior to birth, the young in the womb may feed on undeveloped eggs and possibly their unborn siblings. Litters consist of 2 to 10 pups. Newborns are more than 1 meter (about 3 feet) in length. Gestation is thought to take about 12 months, and females are assumed to give birth in warm temperate and subtropical waters, but specific nursery areas are unknown. Females give birth to live young, unlike many other sharks who lay eggs. It is possible that individual females only reproduce biannually, mating soon after giving birth, but this remains to be confirmed. Male great white sharks reach sexual maturity at 3.5 to 4 meters (about 11.5 to 13 feet) in length and about 10 years of age, whereas females reach sexual maturity at 4.5 to 5 meters (about 15 to 16 feet) in length and 12 to 18 years of age.
Breeding interval: Female sharks may breed every two years.
Breeding season: The breeding season is unknown.
Range number of offspring: 2 to 14.
Average number of offspring: 7.
Average gestation period: 14 months.
Range age at sexual or reproductive maturity (female): 14 to 16 years.
Range age at sexual or reproductive maturity (male): 9 to 10 years.
Key Reproductive Features: iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); ovoviviparous
Newborns get no help from their mothers after birth. As soon as they are born they swim away and are independent. A newborn is about 1.2 m long and grows 25 cm each year, reaching maturity at 10 years (Dale, 2008). Offspring are capable predators the moment they are born.
Parental Investment: no parental involvement; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female)
- 2009. "MarineBio" (On-line). Carcharodon carcharias: Great White Shark. Accessed April 02, 2009 at http://marinebio.org/species.asp?id=38.
- Dale, R. 2008. "OceanLink" (On-line). Great White Shark. Accessed April 06, 2009 at http://oceanlink.island.net/biodiversity/shark/shark.html#Anchor-Habitat.
- Long, D. 2009. "The Great White Shark" (On-line). Accessed April 02, 2009 at http://www.ucmp.berkeley.edu/vertebrates/Doug/shark.html.
- Shark Information - Fresh Development & Image Nation. 2009. "Shark Information" (On-line). Great White Shark. Accessed April 06, 2009 at http://www.sharkinformation.org/great-white-shark/.
Evolution and Systematics
The nostrils of great white sharks can detect minute quantities of blood due to highly sensitive nasal sacs.
"The first of a great white shark's senses to come into play when seeking prey is smell. The nasal sacs in a shark's nostrils can detect minute quantities of blood -- as low as 1 part in 1,000,000,000 -- seeping from an injured animal." (Shuker 2001:40)
Learn more about this functional adaptation.
- Shuker, KPN. 2001. The Hidden Powers of Animals: Uncovering the Secrets of Nature. London: Marshall Editions Ltd. 240 p.
The snout of a great white shark detects minute electrical currents produced by prey using electrosensitive organs called ampullae of Lorenzini.
"Even sightless, the shark is nevertheless still being guided toward its victim by its sensory armory -- by now the shark's electrical sense is operating. Beneath the skin in its snout are numerous tiny, electrosensitive organs known as ampullae of Lorenzini, each linked to the outside world by an external pore. They detect the minute electrical fields produced by the shark's victim and permit the shark to home in on its prey, and to aim with devastating accuracy its first but generally lethal bite." (Shuker 2001:40)
Learn more about this functional adaptation.
- Shuker, KPN. 2001. The Hidden Powers of Animals: Uncovering the Secrets of Nature. London: Marshall Editions Ltd. 240 p.
Molecular Biology and Genetics
Barcode data: Carcharodon carcharias
Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.
See the BOLD taxonomy browser for more complete information about this specimen and other sequences.
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Download FASTA File
Statistics of barcoding coverage: Carcharodon carcharias
Public Records: 12
Specimens with Barcodes: 39
Species With Barcodes: 1
CITES: Listed, Appendix III
Great white sharks are rare throughout their range. This, coupled with their low reproductive rates and persecution by humans means that the IUCN considers them vulnerable. Hunting and bycatch in commercial fisheries exerts significant pressure on great white shark populations and newer estimates may suggest that great white sharks should be considered endangered.
US Federal List: no special status
CITES: appendix ii
State of Michigan List: no special status
IUCN Red List of Threatened Species: vulnerable
IUCN Red List Assessment
Red List Category
Red List Criteria
Despite the high profile media attention the Great White Shark (Carcharodon carcharias) receives, relatively little is known about its biology. It appears to be fairly uncommon compared to other widely distributed species, being most frequently reported from South Africa, Australia, California and the northeast United States. World catches of Great White Sharks from all causes are difficult to estimate, though it is known to have a relatively low intrinsic rebound potential (Smith et al. 1998). Threats to the species include targeted commercial and sports fisheries for jaws, fins, game records and for aquarium display; protective beach meshing; media-fanned campaigns to kill Great White Sharks after a biting incident occurs; and degradation of inshore habitats used as pupping and nursery grounds.
- 1994Insufficiently Known(Groombridge 1994)
- 1990Insufficiently Known(IUCN 1990)
National NatureServe Conservation Status
Rounded National Status Rank: NNR - Unranked
Rounded National Status Rank: NNR - Unranked
NatureServe Conservation Status
Rounded Global Status Rank: GNR - Not Yet Ranked
Recent tagging off South Australia (70-90 animals tagged) has demonstrated a 4-6% recapture rate (Stevens and Bruce pers. Comm.), which may be considered cause for concern. Approximately 40% of 126 Great White Sharks tagged at Dyer Island or Struisbaai, South Africa, between 1992-94 were resighted (Compagno unpubl.). Both the Australian and African research demonstrates at least short-term residency and site-affinity with some pronounced seasonality, coupled to more irregular nomadicity. Off the eastern USA, NMFS statistics from 1965-1983 show a decline from 1:67-1:210 (Casey and Pratt 1985), suggesting a possible decline in abundance. Data from beach meshing programmes in NSW and Queensland show a gradual and irregular decline in CPUE since the 1960s (J.D. Stevens and B. Bruce pers. comm.) whilst trends in KwaZulu-Natal meshing programmes are variable and less clear, but essentially downwards. Other indices of catch-rates are available from: California, between 1960-1985 as 0-14 sharks per year (mean 3.2, Klimley 1985), KwaZulu-Natal, between 1974-1988 as 22-61 sharks per year (Cliff et al. 1989) and the Central Mediterranean Sea (Sicilian Channel), between 1950-1994 as 0-8 sharks per year (mean 2.2, Fergusson unpubl.). We presently have no complete data for Japan, New Zealand or Chile. In other areas, catches are much more nominal and very sporadic (e.g., Brazil, Hawaii).
Relevance to Humans and Ecosystems
Great white sharks can be dangerous to humans partaking in aquatic activities in the ocean such as swimming, diving, surfing, kayaking and canoeing. Great white sharks tend to attack swiftly with a single bite and then retreat. If the bite is minimal, the individual may have a chance to seek safety. However, if the bite is critical, damaging large organs or appendages, death can result for the victim. A review of great white shark attacks off the western United States showed that about 7 percent of attacks were fatal, but data from other localities, such as South Africa, show fatality rates of more than 20 percent. Fatality rates as high as 60 percent have been recorded from attacks in the waters off Australia. Many researchers maintain that attacks on humans stem from the shark’s curiosity. Other authorities contend that these attacks may be the result of the shark mistaking humans for its natural prey, such as seals and sea lions. It is also possible that great white sharks intend to attack humans where their normal prey may be scarce (Long, 2009).
Negative Impacts: injures humans (bites or stings)
Humans hunt great white sharks primarily for sport and for body parts. Great white sharks have developed a reputation in the media as being aggressive and ferocious and as a result they have become a highly prized sport fish. A fully intact jaw of a great white shark can be sold for thousands of dollars. Great white sharks are never abundant because they are at the top of their food chain. In areas that contain great white sharks, boaters and dive operators can earn a living from “shark tourism”. This “shark tourism” allows visitors to see great white sharks up close from the safety of a steel cage suspended in the water (Long, 2009). Traded products that come from great white sharks include fins, jaws, teeth and meat, cartilage, and skin for leather. Liver oil is used in medicines, and the carcass can be used for fish-meal and fertilizer.The trade in shark fins is generally on the increase with records from the Food and Agriculture Organization (FAO) of the United Nations indicating that the international fin trade increased significantly between 1980 and 1990. The demand for shark fin escalated further during the 1990s, making it one of the most expensive fishery products. Jaws and teeth are the most valuable great white shark products in trade.
Positive Impacts: food ; body parts are source of valuable material; ecotourism ; source of medicine or drug ; produces fertilizer
- Norman, B. 2005. "The Great White Shark" (On-line pdf). Accessed April 06, 2009 at www.mesa.edu.au/seaweek2005/pdf_senior/is06.pdf.
Great white shark
The great white shark (Carcharodon carcharias), also known as the great white, white pointer, white shark, or white death, is a species of large lamniform shark which can be found in the coastal surface waters of all the major oceans. The great white shark is mainly known for its size, with mature individuals growing up to 6.4 m (21 ft) in length (although reports have been published of great white sharks measuring over 8 m (26 ft), and 3,324 kg (7,328 lb) in weight). This shark reaches its maturity around 15 years of age and was previously believed to have a life span of over 30 years. The true lifespan of great white sharks is far longer; now estimated to be as long as 70 years or more, making it one of the longest lived cartilaginous fish currently known. Male great white sharks take 26 years to reach sexual maturity, while the females take a whopping 33 years to be ready to produce offspring.  Great white sharks can accelerate to over 56 km/h (35 mph).
The great white shark has no natural predators other than the orca. The great white shark is arguably the world's largest known extant macropredatory fish, and is one of the primary predators of marine mammals. It is also known to prey upon a variety of other marine animals, including fish and seabirds. It is the only known surviving species of its genus Carcharodon, and is ranked first in having the most attacks on humans. The IUCN list the great white shark as a vulnerable species, while it is included in Appendix II of CITES.
The bestselling novel Jaws by Peter Benchley and the subsequent blockbuster film by Steven Spielberg depicted the great white shark as a "ferocious man eater". Humans are not the preferred prey of the great white shark, but the great white is responsible for the largest number of reported and identified fatal unprovoked shark attacks on humans.
- 1 Taxonomy
- 2 Distribution and habitat
- 3 Anatomy and appearance
- 4 Ecology and behavior
- 5 Relationship with humans
- 6 Conservation status
- 7 See also
- 8 References
- 9 External links
In 1758, Carolus Linnaeus gave the great white shark its first scientific name, Squalus carcharias. Later, Sir Andrew Smith gave it Carcharodon as its generic name in 1833, and also in 1873. The generic name was identified with Linnaeus' specific name and the current scientific name, Carcharodon carcharias, was finalized. Carcharodon comes from the Greek words karcharos, which means sharp or jagged, and odous, which means tooth.
Ancestry and fossil record
The great white shark came into existence during the mid-Miocene epoch. The earliest known fossils of the great white shark are about 16 million years old. However, the phylogeny of the great white is still in dispute. The original hypothesis for the great white's origins is that it shares a common ancestor with a prehistoric shark, such as the C. megalodon. C. megalodon had teeth that were superficially not too dissimilar with those great white sharks but its teeth were far larger. Although cartilaginous skeletons do not fossilize, C. megalodon is estimated to have been considerably larger than the great white shark, estimated at up to at least 17 m (56 ft) and 59,413 kg (130,983 lb). Similarities among the physical remains and the extreme size of both the great white and C. megalodon led many scientists to believe these sharks were closely related, and the name Carcharodon megalodon was applied to the latter. However, a new hypothesis proposes that the C. megalodon and the great white are distant relatives (albeit sharing the family Lamnidae). The great white is also more closely related to an ancient mako shark, Isurus hastalis, than to the C. megalodon, a theory that seems to be supported with the discovery of a complete set of jaws with 222 teeth and 45 vertebrae of the extinct transitional species Carcharodon hubbelli in 1988 and published on 14 November 2012. In addition, the new hypothesis assigns C. megalodon to the genus Carcharocles, which also comprises the other megatoothed sharks; Otodus obliquus is the ancient representative of the extinct Carcharocles lineage.
Distribution and habitat
Great white sharks live in almost all coastal and offshore waters which have water temperature between 12 and 24 °C (54 and 75 °F), with greater concentrations in the United States (Atlantic Northeast and California), South Africa, Japan, Oceania, Chile, and the Mediterranean. One of the densest known populations is found around Dyer Island, South Africa, where almost all of the shark research is done.
The great white is an epipelagic fish, observed mostly in the presence of rich game, such as fur seals (Arctocephalus ssp.), sea lions, cetaceans, other sharks, and large bony fish species. In the open ocean, it has been recorded at depths as great as 1,200 m (3,900 ft). These findings challenge the traditional notion about the great white as being a coastal species.
According to a recent study, California great whites have migrated to an area between Baja California and Hawaii known as the White Shark Café to spend at least 100 days before migrating back to Baja. On the journey out, they swim slowly and dive down to around 900 m (3,000 ft). After they arrive, they change behavior and do short dives to about 300 m (1,000 ft) for up to ten minutes. Another white shark that was tagged off of the South African coast swam to the southern coast of Australia and back within the year. A similar study tracked a different great white shark from South Africa swimming to Australia's northwestern coast and back, a journey of 20,000 km (12,000 mi; 11,000 nmi) in under nine months. These observations argue against traditional theories that white sharks are coastal territorial predators, and open up the possibility of interaction between shark populations that were previously thought to have been discrete. The reasons for their migration and what they do at their destination is still unknown. Possibilities include seasonal feeding or mating.
Anatomy and appearance
A great white displays countershading, by having a white underside and a grey dorsal area (sometimes in a brown or blue shade) that gives an overall mottled appearance. The coloration makes it difficult for prey to spot the shark because it breaks up the shark's outline when seen from the side. From above, the darker shade blends with the sea and from below it exposes a minimal silhouette against the sunlight.
Great white sharks, like many other sharks, have rows of serrated teeth behind the main ones, ready to replace any that break off. When the shark bites, it shakes its head side-to-side, helping the teeth saw off large chunks of flesh.
Male great whites reach maturity at 3.5–4.0 m (11.5–13.1 ft) long and females at 4.5–5.0 m (14.8–16.4 ft) long. Adults on average are 4–5.2 m (13–17 ft) long and have a mass of 680–1,100 kg (1,500–2,430 lb). Females are generally larger than males. The great white shark can reach 6.4 m (21 ft) in length and 3,324 kg (7,328 lb) in weight. The maximum size is subject to debate because some reports are rough estimations or speculations performed under questionable circumstances. Among living cartilaginous fish, only the whale shark (Rhincodon typus), the basking shark (Cetorhinus maximus) and the giant manta ray (Manta birostris), in that order, average larger and heavier. These three species are generally quite docile in disposition and given to passively filter-feeding on very small organisms.
A number of very large great white shark specimens have been recorded. For decades, many ichthyological works, as well as the Guinness Book of World Records, listed two great white sharks as the largest individuals: In the 1870s, a 10.9 m (36 ft) great white captured in southern Australian waters, near Port Fairy, and an 11.3 m (37 ft) shark trapped in a herring weir in New Brunswick, Canada, in the 1930s. Some researchers question these measurements' reliability, noting they were much larger than any other accurately reported sighting. This New Brunswick shark may have been a misidentified basking shark, as the two have similar body shapes. The question of the Port Fairy shark was settled in the 1970s when J. E. Randall examined the shark's jaws and "found that the Port Fairy shark was of the order of 5 m (17 ft) in length and suggested that a mistake had been made in the original record, in 1870, of the shark's length".
According to J. E. Randall, the largest white shark reliably measured was a 6.0 m (19.7 ft) individual reported from Ledge Point, Western Australia in 1987. Another great white specimen of similar size has been verified by the Canadian Shark Research Center: A female caught by David McKendrick of Alberton, Prince Edward Island, in August 1988 in the Gulf of St. Lawrence off Prince Edward Island. This female great white was 6.1 m (20 ft) long. However, there is a report considered reliable by some experts of a larger great white shark specimen from Cuba in 1945. This specimen was 6.4 m (21 ft) long and had a body mass of about 3,324 kg (7,328 lb).
Several great white sharks caught in modern times have been estimated to be more than 7 m (23 ft) long, but these claims have received some criticism. However, J. E. Randall believed that great white shark may have exceeded 6.1 m (20 ft) in length. A great white shark was captured near Kangaroo Island in Australia on 1 April 1987. This shark was estimated to be more than 7 m (23 ft) long by Peter Resiley, and has been designated as KANGA. Another great white shark was caught in Malta by Alfredo Cutajar on 16 April 1987. This shark was also estimated to be around 7.13 m (23.4 ft) long by John Abela and has been designated as MALTA. However, Cappo drew criticism because he used shark size estimation methods proposed by J. E. Randall to suggest that the KANGA specimen was 5.8–6.4 m (19–21 ft) long. In a similar fashion, I. K. Fergusson also used shark size estimation methods proposed by J. E. Randall to suggest that the MALTA specimen was 5.3–5.7 m (17–19 ft) long. However, photographic evidence suggested that these specimens were larger than the size estimations yielded through Randall's methods. Thus, a team of scientists—H. F. Mollet, G. M. Cailliet, A. P. Klimley, D. A. Ebert, A. D. Testi, and L. J. V. Compagno—reviewed the cases of the KANGA and MALTA specimens in 1996 to resolve the dispute by conducting a comprehensive morphometric analysis of the remains of these sharks and re-examination of photographic evidence in an attempt to validate the original size estimations and their findings were consistent with them. The findings indicated that estimations by P. Resiley and J. Abela are reasonable and could not be ruled out. A particularly large female great white nicknamed "Deep Blue", measuring at least 6.09 metres (20.0 ft) was filmed off Guadalupe during shooting for the 2014 episode of Shark Week "Jaws Strikes Back". A particularly infamous great white shark, supposedly of record proportions, once patrolled the area that comprises False Bay, South Africa, was said to be well over 7 metres (23 ft) during the early 1980's. This shark, known locally, as the "Submarine", had a legendary reputation that was supposedly well founded. Though rumors have stated this shark was over-exaggerated in size or non-existent altogether, witness accounts by the then young Craig Anthony Ferreira, a notable shark expert in South Africa, and his father indicate an unusually large animal of considerable size and power (though it remains uncertain just how massive the shark was as it escaped capture each time it was hooked). Ferreira describes the four encounters with the giant shark he participated in with great detail in his book "Great White Sharks On Their Best Behavior".
One contender in maximum size among the predatory sharks is the tiger shark (Galeocerdo cuvier). While tiger sharks which are typically both a few feet smaller and have a leaner, less heavy body structure than white sharks, have been confirmed to reach at least 5.5 metres (18 ft) in the length, an unverified specimen was reported to have measured 7.4 metres (24 ft) in length and weighed 3,110 kilograms (6,860 lb). Some other macropredatory sharks such as the Greenland shark (Somniosus microcephalus) and the Pacific sleeper shark (S. pacificus) are also reported to rival these sharks in length (but probably weigh a bit less since they are more slender in build than a great white) in exceptional cases. The question of maximum weight is complicated by the unresolved question of whether or not to include the shark's stomach contents when weighing the shark. With a single bite a great white can take in up to 14 kg (31 lb) of flesh, and can also consume several hundred kilograms of food.
The largest great white recognized by the International Game Fish Association (IGFA) is one caught by Alf Dean in the south Australian waters in 1959, weighing 1,208 kg (2,663 lb). Several larger great whites caught by anglers have since been verified, but were later disallowed from formal recognition by IGFA monitors for rules violations.
Great white sharks, like all other sharks, have an extra sense given by the Ampullae of Lorenzini which enables them to detect the electromagnetic field emitted by the movement of living animals. Every time a living creature moves, it generates an electrical field and great whites are so sensitive they can detect half a billionth of a volt. Even heart beats emit a very faint electrical pulse. If it is close enough, the shark can detect even that faint electrical pulse. Most fish have a less-developed but similar sense using their body's lateral line.
To more successfully hunt fast and agile prey such as sea lions, the great white has adapted to maintain a body temperature warmer than the surrounding water. One of these adaptations is a "rete mirabile" (Latin for "wonderful net"). This close web-like structure of veins and arteries, located along each lateral side of the shark, conserves heat by warming the cooler arterial blood with the venous blood that has been warmed by the working muscles. This keeps certain parts of the body (particularly the stomach) at temperatures up to 14 °C (25 °F) above that of the surrounding water, while the heart and gills remain at sea temperature. When conserving energy the core body temperature can drop to match the surroundings. A great white shark's success in raising its core temperature is an example of gigantothermy. Therefore, the great white shark can be considered an endothermic poikilotherm because its body temperature is not constant but is internally regulated. Great whites also rely on the fat and oils stored within their livers for long distance migrations across nutrient-poor areas of the oceans. Studies by Stanford University and the Monterey Bay Aquarium published on 17 July 2013 revealed that In addition to controlling the sharks' buoyancy, the liver of great whites is essential in migration patterns. Sharks that sink faster during drift dives were revealed to use up their internal stores of energy quicker than those which sink in a dive at more leisurely rates.
A 2007 study from the University of New South Wales in Sydney, Australia, used CT scans of a shark's skull and computer models to measure the shark's maximum bite force. The study reveals the forces and behaviors its skull is adapted to handle and resolves competing theories about its feeding behavior. In 2008, a team of scientists led by Stephen Wroe conducted an experiment to determine the great white shark's jaw power and findings indicated that a specimen more than 6.1 m (20 ft) long could exert a bite force of over 18,000 newtons (4,000 lbf).
Ecology and behavior
This shark's behavior and social structure is not well understood. In South Africa, white sharks have a dominance hierarchy depending on the size, sex and squatter's rights: Females dominate males, larger sharks dominate smaller sharks, and residents dominate newcomers. When hunting, great whites tend to separate and resolve conflicts with rituals and displays. White sharks rarely resort to combat although some individuals have been found with bite marks that match those of other white sharks. This suggests that when another shark approaches too closely to another great white, they react with a warning bite. Another possibility is that white sharks bite to show their dominance.
The great white shark is one of only a few sharks known to regularly lift its head above the sea surface to gaze at other objects such as prey. This is known as spy-hopping. This behavior has also been seen in at least one group of blacktip reef sharks, but this might be learned from interaction with humans (it is theorized that the shark may also be able to smell better this way because smell travels through air faster than through water). The white sharks are generally very curious animals, display intelligence and may also turn to socializing if the situation demands it. At Seal Island, white sharks have been observed arriving and departing in stable "clans" of two to six individuals on a yearly basis. Whether clan members are related is unknown but they get along peacefully enough. In fact, the social structure of a clan is probably most aptly compared to that of a wolf pack; in that each member has a clearly established rank and each clan has an alpha leader. When members of different clans meet, they establish social rank nonviolently through any of a fascinating variety of interactions.
Great white sharks are carnivorous and prey upon fish (e.g. tuna, rays, other sharks), cetaceans (i.e., dolphins, porpoises, whales), pinnipeds (e.g. seals, fur seals, and sea lions), sea turtles, sea otters (Enhydra lutris) and seabirds. Great whites have also been known to eat objects that they are unable to digest. Juvenile white sharks predominantly prey on fish including other elasmobranchs, as their jaws are not strong enough to withstand the forces required to attack larger prey such as pinnipeds and cetaceans until they reach a length of 3 metres (9.8 ft) or more, at which point their jaw cartilage mineralizes enough to withstand the impact of biting into larger prey species. Upon approaching a length of nearly 4 metres (13 ft), great white sharks begin to target predominately marine mammals for food, though individual sharks seem to specialize in different types of prey depending on their preferences. They seem to be highly opportunistic. These sharks prefer prey with a high content of energy-rich fat. Shark expert Peter Klimley used a rod-and-reel rig and trolled carcasses of a seal, a pig, and a sheep from his boat in the South Farallons. The sharks attacked all three baits but rejected the sheep carcass.
The great white shark's reputation as a ferocious predator is well-earned, yet they are not (as was once believed) indiscriminate "eating machines". They are ambush hunters, taking prey by surprise from below. Near Seal Island, in South Africa's False Bay, shark attacks most often occur in the morning, within 2 hours after sunrise, when visibility is poor. Their success rate is 55% in the first 2 hours, falling to 40% in late morning after which hunting stops.
Hunting techniques vary by species of the prey. Off Seal Island, the sharks ambush brown fur seals (Arctocephalus pusillus) from below at high speeds, hitting the seal mid-body. They go so fast that they can completely leave the water. The peak burst speed of these sharks is largely accepted in the scientific community to be above 40 kilometres per hour (25 mph). However further precision is still speculative. They have also been observed chasing prey after a missed attack. Prey is usually attacked at the surface. When hunting sea turtles, they appear to simply bite through the carapace around a flipper immobilizing the turtle. The heaviest species of bony fish, the oceanic sunfish (Mola mola), has been found in great white shark stomachs.
Off California, sharks immobilize northern elephant seals (Mirounga angustirostris) with a large bite to the hindquarters (which is the main source of the seal's mobility) and wait for the seal to bleed to death. This technique is especially used on adult male elephant seals, which are typically rather larger than the shark at an average range of 1,500 to 2,000 kg (3,300 to 4,400 lb), and are potentially dangerous adversaries. Most commonly, though juvenile elephant seals are the most frequently eaten at elephant seal colonies. Prey is normally attacked sub-surface. Harbour seals (Phoca vitulina) are taken from the surface and dragged down until they stop struggling. They are then eaten near the bottom. California sea lions (Zalophus californianus) are ambushed from below and struck mid-body before being dragged and eaten.
Off the East Coast of North America, where white sharks are still poorly understood, individuals have been filmed and documented hunting grey seals (Halichoerus grypus). When hunting, Atlantic great whites will hunt very close to shore, unlike their counterparts elsewhere which prefer deeper water for ambush and breach attacks. The sharks also utilize sandbars to set up ambushes, and will then chase the seals in a flat-out pursuit. This behavior was revealed to the public media during two episodes of Shark Week, the first being "Jaws Comes Home" and the second being "Return of Jaws".
White sharks also attack dolphins and porpoises from above, behind or below to avoid being detected by their echolocation. Targeted species include dusky dolphins (Lagenorhynchus obscurus), Risso's dolphins (Grampus griseus), bottlenose dolphins (Tursiops ssp.), Humpback dolphins (Sousa ssp.), harbour porpoises (Phocoena phocoena), and Dall's porpoises (Phocoenoides dalli). Close encounters between dolphins and predatory sharks often result in evasive responses by the dolphins. However, in rare cases, a group of dolphins may chase a single predatory shark away in an act of defense. White shark predation on other species of small cetacean has also been observed. In August 1989, a 1.8 metres (5.9 ft) juvenile male pygmy sperm whale (Kogia breviceps) stranded in central California with a bite mark on its caudal peduncle from a great white shark. In addition, white sharks also attack and prey upon beaked whales. Cases where an adult Stejneger's beaked whale (Mesoplodon stejnegeri), with a mean mass of around 1,100 kg (2,400 lb), and a juvenile Cuvier's beaked whale (Ziphius cavirostris), an individual estimated at 3 m (9.8 ft), were hunted and killed by great white sharks have also been observed.
Even though the great whites are known to generally avoid conflicts with each other, the phenomenon of cannibalism is not alien to this species. Large individuals may aggressively interact intraspecifically with small individuals. A 3 m (9.8 ft) long great white shark was nearly bitten into two by a reportedly 6 m (20 ft) long great white shark in Stradbroke Island, near Brisbane in Australia.
White sharks also scavenge on whale carcasses, a phenomenon that often leads to interactions and possibly shapes the ecosystem impacts, behaviors and movements. Larger white sharks feed first, primarily on the blubber, with smaller animals feeding off chunks dislodged or torn from the carcasses that float away. Interestingly, white sharks prefer to feed off the fluke first before moving to other portions of the body. The discovery also lends credence to the theory that large white sharks travel throughout ocean corridors in search of dead, dying and severely injured whales as well as bringing their predations on seals to temporary halts. In one such documented incident, white sharks were observed scavenging on a whale carcass alongside tiger sharks.
Almost nothing is known about the reproduction of great whites. Some evidence points to the near-soporific effect of a large feast (such as a whale carcass) possibly inducing mating. Great white sharks were previously thought to reach sexual maturity at around 15 years of age, but actually take far longer; male great white sharks reach sexual maturity at age 26, while females take 33 years to reach sexual maturity.  Maximum life span was originally believed to be more than 30 years, but in a study by the Woods Hole Oceanographic Institution, the true lifespan of the great white shark was revealed to be up to 70 years or more, with examinations of growth ring count in vertebrae including ages of 73 years old in the oldest male and 40 years old in the oldest female in the study, making the species far more vulnerable to pressures such as overfishing and environmental change due to their late maturity, low reproductive rate and slow growth. (see references).
Little is known about the great white shark's behavior in the way of mating habits. Birth has never been observed, but pregnant females have been examined. Great white sharks are ovoviviparous, which means eggs develop and hatch in the uterus and continue to develop until birth. The great white has an 11-month gestation period. The shark pup's powerful jaws begin to develop in the first month. The unborn sharks participate in oophagy, in which they feed on ova produced by the mother. Delivery is in spring and summer. The Northern Pacific population of great whites is suspected to breed off of the Sea of Cortez (as was revealed in the Shark Week episode "Spawn of Jaws"), as evidenced by local fisherman who have said to have caught them and evidenced by teeth found at dump sites for discarded parts from their catches. If the Sea of Cortez is such a breeding ground, it is imperative that the area's laws be better enforced to ensure the survival of the breeding population.
A breach is the result of a high speed approach to the surface with the resulting momentum taking the shark partially or completely clear of the water. This is a hunting technique employed by great white sharks whilst hunting seals. This behavior often takes place on cape fur seals at Seal Island in False Bay, South Africa but due to the randomness of the location of a shark's breach, it was very hard to document. It was first photographed by Chris Fallows and Rob Lawrence who developed the technique of towing a slow moving seal decoy to trick the sharks to breach. Here, in the region of 600 natural predatory events are recorded annually from April to September each year. The seals swim on the surface and the great white sharks launch their predatory attack from the deeper water below. They can reach speeds of up to 40 kilometres per hour (25 mph) and can at times launch themselves more than 10 feet (3.0 m) into the air. Data recorded shows that the sharks are successful in just under 50% of all these natural predatory events. In 2011, a 3 metres (9.8 ft) long shark jumped onto a seven-person research vessel off Seal Island in Mossel Bay. The crew were undertaking a population study using sardines as bait, and the incident was judged to be an accident.
Interspecific competition between the great white shark and the orca is probable in regions where dietary preferences of both species may overlap. An incident was documented on 4 October 1997, in the Farallon Islands off California in the United States. An estimated 4.7–5.3-metre (15–17 ft) female orca immobilized an estimated 3–4-metre (9.8–13.1 ft) great white shark. The orca held the shark upside down to induce tonic immobility and kept the shark still for fifteen minutes, causing it to suffocate and then proceeded to eat the dead shark's liver. It is believed that the scent of the slain shark's carcass caused all the great whites in the region to flee, forfeiting an opportunity for a great seasonal feed. Another similar attack apparently occurred there in 2000, but its outcome is not clear. After both attacks, the local population of about 100 great whites vanished. Following the 2000 incident, a great white with a satellite tag was found to have immediately submerged to a depth of 500 m (1,600 ft) and swam to Hawaii.
Relationship with humans
Of all shark species, the great white shark is responsible for by far the largest number of recorded shark attacks on humans, with 272 documented unprovoked attacks on humans in which the great white shark was identified as of 2012.
More than any documented attack, Peter Benchley's best-selling novel Jaws and the subsequent 1975 film adaptation directed by Steven Spielberg provided the great white shark with the image of being a "man eater" in the public mind. While great white sharks have killed humans in at least 74 documented unprovoked attacks in which the species was identified, they typically do not target them: for example, in the Mediterranean Sea there have been 31 confirmed attacks against humans in the last two centuries, most of which were non-fatal. Many of the incidents seemed to be "test-bites". Great white sharks also test-bite buoys, flotsam, and other unfamiliar objects, and they might grab a human or a surfboard to identify what it is.
Contrary to popular belief, great white sharks do not mistake humans for seals. Many attacks occur in waters with low visibility or other situations which impair the shark's senses. The species appears to not like the taste of humans, or at least finds the taste unfamiliar. Further research shows that they can tell in one bite whether or not the object is worth attacking. Humans, for the most part, are too bony for their liking. They much prefer a fat, protein-rich seal.
Humans are not appropriate prey because the shark's digestion is too slow to cope with a human's high ratio of bone to muscle and fat. Accordingly, in most recorded attacks, great whites broke off contact after the first bite. Fatalities are usually caused by blood loss from the initial bite rather than from critical organ loss or from whole consumption. From 1990 until 2011 there have been a total of 139 unprovoked great white shark attacks, 29 fatal.
However, some researchers have hypothesized that the reason the proportion of fatalities is low is not because sharks do not like human flesh, but because humans are often able to escape after the first bite. In the 1980s John McCosker, the Chair of Aquatic Biology at California Academy, noted that divers who dove solo and were attacked by great whites were generally at least partially consumed, while divers who followed the buddy system were generally rescued by their buddy. McCosker and Timothy C. Tricas, an author and professor at the University of Hawaii, suggest that a standard pattern for great whites is to make an initial devastating attack and then wait for the prey to weaken before consuming the wounded animal. Humans' ability to move out of reach with the help of others, thus foiling the attack, is unusual for a great white's prey.
In 2014 the state government of Western Australia led by Premier Colin Barnett implemented a policy of killing large sharks. The policy is intended to protect users of the marine environment from shark attack following the deaths of seven people on the Western Australian coastline in the years 2010 to 2013. Baited drum lines are deployed near popular beaches using hooks designed to catch great white sharks, as well as bull and tiger sharks. Large sharks found hooked but still alive are shot and their bodies discarded at sea. The government claims they are not culling the sharks, but are using a "targeted, localised, hazard mitigation strategy". Barnett has described opposition as "ludicrous" and "extreme", and said that nothing can change his mind.
Attacks on boats
Great white sharks infrequently attack and sometimes even sink boats. Only five of the 108 authenticated unprovoked shark attacks reported from the Pacific Coast during the 20th century involved kayakers. In a few cases they have attacked boats up to 10 metres (33 ft) in length. They have bumped or knocked people overboard, usually attacking the boat from the stern. In one case in 1936, a large shark leapt completely into the South African fishing boat Lucky Jim, knocking a crewman into the sea. Tricas and McCosker's underwater observations suggest that sharks are attracted to boats due to the electrical fields they generate.
Great white sharks in captivity
Prior to August 1981, no great white shark in captivity lived longer than 11 days. In August 1981, a white shark survived for 16 days at SeaWorld San Diego before being released. The idea of containing a live great white at SeaWorld Orlando was used in the 1983 film Jaws 3-D.
In 1984, shortly before its opening day, the Monterey Bay Aquarium in Monterey, California, housed its first great white shark which had died after 10 days. In July 2003, Monterey researchers captured a small female and kept it in a large netted pen near Malibu for five days. They had the rare success of getting the shark to feed in captivity before its release. Not until September 2004 was the aquarium able to place a great white on long-term exhibit. A young female, which was caught off the coast of Ventura, was kept in the aquarium's 3,800,000-litre (1,000,000 US gal) Outer Bay exhibit for 198 days before she was released in March 2005. She was tracked for 30 days after release. On the evening of 31 August 2006, the aquarium introduced a juvenile male caught outside Santa Monica Bay. His first meal as a captive was a large salmon steak on 8 September 2006, and as of that date, he was estimated to be 1.72 metres (68 in) in length and to weigh approximately 47 kilograms (104 lb). He was released on 16 January 2007, after 137 days in captivity.
Monterey Bay Aquarium housed a third great white, a juvenile male, for 162 days between 27 August 2007, and 5 February 2008. On arrival, he was 1.4 m (4.6 ft) long and weighed 30.6 kg (67 lb). He grew to 1.8 m (5.9 ft) and 64 kg (141 lb) before release. A juvenile female came to the Outer Bay Exhibit on 27 August 2008. While she did swim well, the shark fed only one time during her stay and was tagged and released on 7 September 2008. Another juvenile female was captured near Malibu on 12 August 2009, introduced to the Outer Bay exhibit on 26 August 2009, and was successfully released into the wild on 4 November 2009. The Monterey Bay Aquarium added a 1.4 metres (4.6 ft) long male into their redesigned "Open Sea" exhibit on 31 August 2011. The animal was captured in the waters off of Malibu.
Probably the most famous captive was a 2.4 m (7.9 ft) female named Sandy, which in August 1980 became the only great white to be housed at the California Academy of Sciences' Steinhart Aquarium in San Francisco, California. She was released because she would not eat and constantly bumped against the walls.
Cage diving is most common at sites where great whites are frequent including the coast of South Africa, the Neptune Islands in South Australia, and Guadalupe Island in Baja California. Cage diving and swimming with sharks is a focus for a booming tourist industry due to its popularity. A common practice is to chum the water with pieces of fish to attract the sharks. These practices may make sharks more accustomed to people in their environment and to associate human activity with food; a potentially dangerous situation. By drawing bait on a wire towards the cage, tour operators lure the shark to the cage, possibly striking it, exacerbating this problem. Other operators draw the bait away from the cage, causing the shark to swim past the divers.
At present, hang baits are illegal off Isla Guadalupe and reputable dive operators do not use them. Operators in South Africa and Australia continue to use hang baits and pinniped decoys. In South Australia, playing rock music recordings underwater, including the AC/DC album Back in Black has also been used experimentally to attract sharks.
Companies object to being blamed for shark attacks, pointing out that lightning tends to strike humans more often than sharks bite humans. Their position is that further research needs to be done before banning practices such as chumming, which may alter natural behavior. One compromise is to only use chum in areas where whites actively patrol anyway, well away from human leisure areas. Also, responsible dive operators do not feed sharks. Only sharks that are willing to scavenge follow the chum trail and if they find no food at the end then the shark soon swims off and does not associate chum with a meal. It has been suggested that government licensing strategies may help enforce these suggested advisories.
The shark tourist industry has some financial leverage in conserving this animal. A single set of great white jaws can fetch a one-time price of up to £20,000. That is a fraction of the tourism value of a live shark, a more sustainable economic activity. For example, the dive industry in Gansbaai, South Africa, consists of six boat operators with each boat guiding 30 people each day. With fees between £50 to £150 per person, a single live shark that visits each boat can create anywhere between £9,000 and £27,000 of revenue daily.
It is unclear how much of a concurrent increase in fishing for great white sharks has caused the decline of great white shark populations from the 1970s to the present. No accurate global population numbers are available, but the great white shark is now considered vulnerable. Sharks taken during the long interval between birth and sexual maturity never reproduce, making population recovery and growth difficult.
The IUCN notes that very little is known about the actual status of the great white shark, but as it appears uncommon compared to other widely distributed species, it is considered vulnerable. It is included in Appendix II of CITES, meaning that international trade in the species requires a permit. As of March 2010, it has also been included in Annex I of the CMS Migratory Sharks MoU, which strives for increased international understanding and coordination for the protection of certain migratory sharks. A February 2010 study by Barbara Block of Stanford University estimated the world population of great white sharks to be lower than 3,500 individuals, making the species more vulnerable to extinction than the tiger, whose population is in the same range. According to another study from 2014 by George H. Burgess, Florida Museum of Natural History, University of Florida, there are about 2000 White sharks, near California coast alone, which is 10 times higher than previous estimate of 219 by Barbara Block.
Fishermen target many sharks for their jaws, teeth, and fins, and as game fish in general. The great white shark, however, is rarely an object of commercial fishing, although its flesh is considered valuable. If casually captured (it happens for example in some tonnare in the Mediterranean), it is misleadingly sold as smooth-hound shark.
The great white shark was declared as Vulnerable by the Australian Government in 1999 due to significant population decline and is currently protected under the Environmental Protection and Biodiversity Conservation (EPBC) Act. The causes of decline prior to protection included mortality from sport fishing harvests as well as being caught in beach protection netting.
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. 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.
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. An updated recovery plan was published in 2013 to review progress, research findings, and to implement further conservation actions. 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.
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.
In New Zealand
As of April 2007, great white sharks were fully protected within 370 kilometres (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.
In North America
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 is 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.
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