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90-403: The tiger shark ( Galeocerdo cuvier ) is a species of ground shark , and the only extant member of the genus Galeocerdo and family Galeocerdonidae. It is a large macropredator, with females capable of attaining a length of over 5 m (16 ft 5 in). Populations are found in many tropical and temperate waters, especially around central Pacific islands. Its name derives from

180-577: A near threatened species due to excessive finning and fishing by humans according to International Union for Conservation of Nature . In June 2018, the New Zealand Department of Conservation classified the tiger shark as "Migrant" with the qualifier "Secure Overseas" under the New Zealand Threat Classification System . While shark fin has very few nutrients, shark liver has a high concentration of vitamin A , which

270-455: A standard length of 15 m (49.2 ft) and an estimated total length at 18.8 m (61.7 ft) was reported from the Arabian Sea in 2001. In a 2015 study reviewing the size of marine megafauna , McClain and colleagues considered this female as being the most reliable and accurately measured. On 7 February 2012, a large whale shark was found floating 150 kilometres (93 mi) off

360-400: A "garbage eater", consuming a variety of inedible, man-made objects that linger in its stomach. Tiger sharks have only one recorded natural predator, the orca . It is considered a near threatened species because of finning and fishing by humans. The tiger shark is second only to the great white in recorded fatal attacks on humans, but these events are still exceedingly rare. The shark

450-587: A fluid that nourishes them. This allows for the young to dramatically increase in size, even though they have no placental connection to the mother. The young develop inside the mother's body up to 16 months. Litters range from 10 to 80 pups. A newborn is generally 51 to 76 cm (20 to 30 in) long. How long tiger sharks live is unknown, but they can live longer than 12 years. Tiger shark ontogeny has been little studied until recently, but studies by Hammerschlag et al. , indicated that as they grow, their tails become more symmetrical with age. Additionally, while

540-591: A large share of fatal shark-bite incidents, and is regarded as one of the most dangerous shark species. They often visit shallow reefs, harbors, and canals, creating the potential for encounter with humans. The tiger shark also dwells in river mouths and other runoff-rich water. While it ranks second on the list of number of recorded shark attacks on humans, behind only the great white shark, such attacks are few and very seldom fatal. Typically, three to four shark bites occur per year in Hawaii; one notable survivor of such an attack

630-463: A larger male unsuccessfully attempted to mate with a smaller, immature female. The capture of a ~10.6 m (35 ft) female in July 1996 that was pregnant with ~300 pups indicated that whale sharks are ovoviviparous . The eggs remain in the body and the females give birth to live young which are 40 to 60 cm (16 to 24 in) long. Evidence indicates the pups are not all born at once, but rather

720-541: A larger upper lobe than the lower lobe ( heterocercal ). Whale sharks have been found to possess dermal denticles on the surface of their eyeballs that are structured differently from their body denticles. The dermal denticles, as well as the whale shark's ability to retract its eyes deep into their sockets, serve to protect the eyes from damage. Evidence suggests that whale sharks can recover from major injuries and may be able to regenerate small sections of their fins. Their spot markings have also been shown to reform over

810-418: A previously wounded area. The complete and annotated genome of the whale shark was published in 2017. Rhodopsin , the light-sensing pigment in the rod cells of the retina, is normally sensitive to green and used to see in dim light, but in the whale shark (and the bottom-dwelling cloudy catshark ) two amino acid substitutions make the pigment more sensitive to blue light instead, the light that dominates

900-404: A record of an exceptional 7.4-metre (24 ft 3 in), 3,110-kilogram (6,860 lb) tiger shark, but since this is far larger than any scientifically observed specimen, verification would be needed. A 2019 study suggested that Pliocene tiger sharks could have reached 8 m (26 ft) in maximum length. There is variation in the speed of growth rates of juvenile tiger sharks depending on

990-579: A shark cage in a 2007 Discovery Channel special, and underwater photographer Fiona Ayerst swam with them in the Bahamas . At "Tiger Beach" off Grand Bahama, uncaged diving with – and even the handling of – female tiger sharks has become a routine occurrence. Warming Atlantic Ocean currents have caused tiger shark migration paths to move further north, according to a University of Miami study. Tiger sharks are considered to be sacred ʻaumākua (ancestor spirits) by some native Hawaiians . Tiger sharks possess

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1080-471: A symmetrical tail is more advantageous in long-distance traveling, and that tiger sharks consume more diverse prey items with age, which requires a greater bite force and broader head. The tiger shark is captured and killed for its fins , flesh , and liver . It is caught regularly in target and nontarget fisheries. Several populations have declined where they have been heavily fished. Continued demand for fins may result in further declines. They are considered

1170-520: A tiger shark attacked and killed a 23-year-old Russian man in the Red Sea off the coast of the Egyptian city of Hurghada . The attack was filmed by onlookers and the recording went viral . The shark was later captured by fishermen and killed. This was the third fatal tiger shark attack in the area since 2022. Between 1959 and 1976, 4,668 tiger sharks were culled in the state of Hawaii in an effort to protect

1260-483: A tiger shark can typically range from blue to light green with a white or light-yellow underbelly. The advantage of this is that when it is hunting for its prey, when prey looks at the shark from above, the shark will be camouflaged, since the water below is darker. When prey is below the shark and looks up the light underbelly will also camouflage the shark with the sunlight. This is known as countershading . Dark spots and stripes are most visible in young sharks and fade as

1350-499: A unique significance as ʻaumakua, revered as family guardians in Hawaiian culture. The tiger shark, regarded as an intelligent and highly perceptive spiritual entity, assumes the role of a messenger bridging the gap between humans and the divine. In the Hawaiian belief system, ʻaumakua take on various forms, either animals or objects, representing ancestral connections and manifestations of departed family members. This perspective underscores

1440-462: A very large tank is required and it has specialized feeding requirements. Their large size and iconic status have also fueled an opposition to keeping the species in captivity, especially after the early death of some whale sharks in captivity and certain Chinese aquariums keeping the species in relatively small tanks. The first attempt at keeping whale sharks in captivity was in 1934 when an individual

1530-471: A whale shark feeding on a school of small fish. The same documentary showed footage of a whale shark timing its arrival to coincide with the mass spawning of fish shoals and feeding on the resultant clouds of eggs and sperm. Whale sharks are known to prey on a range of planktonic and small nektonic organisms that are spatiotemporally patchy. These include krill, crab larvae, jellyfish, sardines, anchovies, mackerels, small tunas, and squid. In ram filter feeding,

1620-428: Is surfing champion Bethany Hamilton , who lost her left arm at age 13 to a tiger shark in 2003. This bite rate is very low, considering that thousands of people swim, surf, and dive in Hawaiian waters every day. Human interactions with tiger sharks in Hawaiian waters have been shown to increase between September and November, when tiger shark females are believed to migrate to the islands to give birth. On 8 June 2023,

1710-657: Is 810 kg (1,790 lb). It is sexually dimorphic , with females being the larger sex. Mature females are often over 3.7 m (12 ft 2 in) while mature males rarely get that large. Exceptionally large females reportedly can measure over 5 m (16 ft 5 in), and the largest males 4 m (13 ft 1 in). Weights of particularly large female tiger sharks can exceed 1,300 kg (2,900 lb). One pregnant female caught off Australia reportedly measured 5.5 m (18 ft 1 in) long and weighed 1,524 kg (3,360 lb). Even larger unconfirmed catches have been claimed. Some papers have accepted

1800-581: Is a feeding mode that occurs in only two other sharks, the megamouth shark and the basking shark . They feed almost exclusively on plankton and small fishes and pose no threat to humans. The species was distinguished in April 1828 after the harpooning of a 4.6 m (15 ft) specimen in Table Bay , South Africa. Andrew Smith , a military doctor associated with British troops stationed in Cape Town , described it

1890-789: Is an apex predator and has a reputation for eating almost anything. These predators swim close inland to eat at night, and during the day swim out into deeper waters. Young tiger sharks are found to feed largely on small fish , as well as various small jellyfish , and mollusks including cephalopods . Around the time they attain 2.3 m (7.5 ft), or near sexual maturity, their selection expands considerably, and much larger animals become regular prey. Numerous fish , mollusks (including gastropods and cephalopods), crustaceans , sea birds , sea snakes , marine mammals (e.g. bottlenose dolphins ( Tursiops ), common dolphins ( Delphinus ), spotted dolphins ( Stenella ), dugongs ( Dugong dugon ), seals and sea lions ), and sea turtles (including

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1980-404: Is an active feeder, targeting concentrations of plankton or fish. It is able to ram filter feed or can gulp in a stationary position. This is in contrast to the passive feeding basking shark, which does not pump water. Instead, it swims to force water across its gills. A juvenile whale shark is estimated to eat 21 kg (46 pounds) of plankton per day. The BBC program Planet Earth filmed

2070-540: Is around 80 to 130 kg (180 to 290 lb). Females mate once every three years. They breed by internal fertilization. The male inserts one of his claspers into the female's genital opening ( cloaca ), acting as a guide for the sperm . The male uses his teeth to hold the female still during the procedure, often causing the female considerable discomfort. Mating in the Northern Hemisphere generally takes place between March and May, with birth between April and June

2160-723: Is seen by divers in many places, including the Bay Islands in Honduras, Thailand, Indonesia ( Bone Bolango , Cendrawasih Bay ), the Philippines, the Maldives close to Maamigili (South Ari Atoll), the Red Sea , Western Australia ( Ningaloo Reef , Christmas Island ), Taiwan, Panama ( Coiba Island ), Belize, Tofo Beach in Mozambique, Sodwana Bay ( Greater St. Lucia Wetland Park ) in South Africa,

2250-427: Is unique to each individual. The skin can be up to 15 cm (5.9 in) thick and is very hard and rough to the touch. The whale shark has three prominent ridges along its sides, which start above and behind the head and end at the caudal peduncle . The shark has two dorsal fins set relatively far back on the body, a pair of pectoral fins , a pair of pelvic fins and a single medial anal fin . The caudal fin has

2340-405: Is used in the production of vitamin oils. In addition, the tiger shark is captured and killed for its distinct skin, as well as by big-game fishers. In 2010, Greenpeace International added the tiger shark to its seafood red list, which is a list of commonly sold fish likely to come from unsustainable fisheries. Although sharks rarely bite humans, the tiger shark is reported to be responsible for

2430-771: Is used to model growth curves, which can predict asymptotic length. The growth curves produced from these studies have estimated asymptotic lengths ranging from 15 to 21.9 meters (49 to 72 ft). A 2020 study looked at the growth of whale shark individuals over a 10-year period around the Ningaloo Reef and concluded the species exhibits sexual dimorphism with regard to size, with females growing larger than males. The study found that males on average reach 8 to 9 meters (26 to 30 ft) in length. The same study had less female data but estimated an average length of around 14.5 m (48 ft). However, this value dropped to 12.1 m (40 ft) if data from aquarium whale sharks

2520-507: The Eocene epoch, while the oldest fossils of the modern tiger shark Galeocerdo cuvier date to the Middle Miocene , around 13.8 million years ago. The tiger shark commonly attains adult length of 3.5 to 4.7 m (11 ft 6 in – 15 ft 5 in) and weighs between 300 and 900 kg (700 and 2,000 lb). The International Game Fish Association 's all-tackle record

2610-657: The Galapagos Islands, Saint Helena , Isla Mujeres ( Caribbean Sea ), La Paz, Baja California Sur and Bahía de los Ángeles in Mexico , the Seychelles , West Malaysia , islands off eastern peninsular Malaysia , India , Sri Lanka , Oman , Fujairah , Puerto Rico , and other parts of the Caribbean . Juveniles can be found near the shore in the Gulf of Tadjoura , near Djibouti , in

2700-513: The Horn of Africa . There is currently no robust estimate of the global whale shark population. The species is considered endangered by the IUCN due to the impacts of fisheries, by-catch losses, and vessel strikes, combined with its long lifespan and late maturation. In June 2018 the New Zealand Department of Conservation classified the whale shark as "Migrant" with the qualifier "Secure Overseas" under

2790-594: The Late Cretaceous , initially as mostly small-sized forms, before radiating into medium and large body sizes during the Cenozoic . Eschmeyer's Catalog of Fishes classifies the Carcharhiniformes into two suborders and nine families: The following fossil genera of Carcharhiniformes are also known: Whale shark The whale shark ( Rhincodon typus ) is a slow-moving, filter-feeding carpet shark and

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2880-468: The Mississippi River Delta , where one-third of all whale shark sightings in the northern part of the gulf have occurred in recent years. Sightings confirmed that the whale sharks were unable to avoid the oil slick, which was situated on the surface of the sea where the whale sharks feed for several hours at a time. No dead whale sharks were found. This species was also added to Appendix II of

2970-653: The New Zealand Threat Classification System . It is listed, along with six other species of sharks, under the CMS Memorandum of Understanding on the Conservation of Migratory Sharks . In 1998, the Philippines banned all fishing, selling, importing, and exporting of whale sharks for commercial purposes, followed by India in May 2001 and Taiwan in May 2007. In 2010, the Gulf of Mexico oil spill resulted in 4,900,000 barrels (780,000 m ) of oil flowing into an area south of

3060-442: The megamouth shark ). It feeds on plankton including copepods , krill , fish eggs , Christmas Island red crab larvae and small nektonic life, such as small squid or fish . It also feeds on clouds of eggs during mass spawning of fish and corals. The many rows of vestigial teeth play no role in feeding. Feeding occurs either by ram filtration, in which the animal opens its mouth and swims forward, pushing water and food into

3150-528: The tapetum lucidum , allows light-sensing cells a second chance to capture photons of visible light. This enhances vision in low-light conditions. The tiger shark is often found close to the coast, mainly in tropical and subtropical waters throughout the world. Its behavior is primarily nomadic , but is guided by warmer currents, and it stays closer to the equator throughout the colder months. It tends to stay in deep waters that line reefs, but it does move into channels to pursue prey in shallower waters. In

3240-474: The tourism industry. Despite damaging the shark population, these efforts were shown to be ineffective in decreasing the number of interactions between humans and tiger sharks. Feeding sharks in Hawaii (except for traditional Hawaiian cultural or religious practices) is illegal, and interaction with them, such as cage diving , is discouraged. South African shark behaviorist and shark diver Mark Addison demonstrated divers could interact and dive with them outside of

3330-557: The " garbage can of the sea ". Tiger sharks are preyed on by orcas . Orcas have been recorded hunting and killing tiger sharks by holding them upside down to induce tonic immobility in order to drown the shark. The orcas bite off the shark's fins before disemboweling and devouring it. All tiger sharks generally swim slowly, which, combined with cryptic coloration, may make them difficult for prey to detect in some habitats. They are especially well camouflaged against dark backgrounds. Despite their sluggish appearance, tiger sharks are one of

3420-560: The Australian coast. Additionally, examination of adult dugongs has shown scars from failed shark attacks. To minimize attacks, dugong microhabitats shift similarly to those of known tiger shark prey when the sharks are abundant. The broad, heavily calcified jaws and nearly terminal mouth, combined with robust, serrated teeth, enable the tiger shark to take on these large prey. In addition, excellent eyesight and acute sense of smell enable it to react to faint traces of blood and follow them to

3510-567: The Convention on International Trade in Endangered Species of Wild Fauna and Flora ( CITES ) in 2003 to regulate the international trade of live specimens and its parts. It was reported in 2014 that hundreds of whale sharks were illegally killed every year in China for their fins, skins, and oil. The whale shark is popular in the few public aquariums that keep it, but its large size means that

3600-798: The Galápagos, Quintana Roo in Mexico, Mafia Island of Pwani Region in Tanzania, Inhambane province in Mozambique, the Philippines , around Mahe in the Seychelles, the Gujarat and Kerala coasts of India, Taiwan , southern China and Qatar . In 2011, more than 400 whale sharks gathered off the Yucatan Coast. It was one of the largest gatherings of whale sharks recorded. Aggregations in that area are among

3690-533: The accuracy of in-water measurements, including underwater and aerial techniques. Since the 1800s, there have been accounts of very large whale sharks. Some of these are as follows: In 1868, the Irish natural scientist Edward Perceval Wright obtained several small whale shark specimens in the Seychelles . Wright was informed of one whale shark that was measured as exceeding 45 ft (14 m). Wright claimed to have observed specimens over 50 ft (15 m) and

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3780-533: The approximate average of 1.7 to 1.8 m (5.6–5.9 ft), based on the local fishermen. Later sources have stated this whale shark as approximately 18 m (59 ft), but the accuracy of the estimate has been questioned. In 1934, a ship named the Maunganui came across a whale shark in the southern Pacific Ocean and rammed it. The shark became stuck on the prow of the ship, supposedly with 15 ft (4.6 m) on one side and 40 ft (12.2 m) on

3870-508: The area. Large adult females, often pregnant, are a seasonal presence around the Galapagos Islands, which may have reproductive significance. One study between 2011 and 2013 found that 91.5% of the whale sharks observed around Darwin Island were adult females. The whale shark is a filter feeder – one of only three known filter-feeding shark species (along with the basking shark and

3960-780: The basic research on the keeping of the species was made at these two institutions. Since the mid-1990s, several other aquariums have kept the species in Japan ( Kagoshima Aquarium , Kinosaki Marine World, Notojima Aquarium , Oita Marine Palace Aquarium , and Yokohama Hakkeijima Sea Paradise ), South Korea ( Aqua Planet Jeju ), China ( Chimelong Ocean Kingdom , Dalian Aquarium, Guangzhou Aquarium in Guangzhou Zoo, Qingdao Polar Ocean World and Yantai Aquarium), Taiwan ( National Museum of Marine Biology and Aquarium ), India (Thiruvananthapuram Aquarium) and Dubai ( Atlantis, The Palm ), with some maintaining whale sharks for years and others only for

4050-537: The capture/stranding and some were released, but initial captive survival rates were low. After the initial difficulties in maintaining the species had been resolved, some have survived long-term in captivity. The record for a whale shark in captivity is an individual that, as of 2021, has lived for more than 26 years in the Okinawa Churaumi Aquarium from Okinawa Ocean Expo Aquarium. Following Okinawa, Osaka Aquarium started keeping whale sharks and most of

4140-452: The class Chondrichthyes . Before 1984 it was classified as Rhiniodon into Rhinodontidae. Whale sharks inhabit the open waters of all tropical oceans. They are rarely found in water below 21 °C (70 °F). Whale sharks' lifespans are estimated to be between 80 and 130 years, based on studies of their vertebral growth bands and the growth rates of free-swimming sharks. Whale sharks have very large mouths and are filter feeders, which

4230-502: The coast of Karachi , Pakistan. The length of the specimen was said to be between 11 and 12 m (36 and 39 ft), with a weight of around 15,000 kg (33,000 lb). The whale shark inhabits all tropical and warm-temperate seas. The fish is primarily pelagic , and can be found in both coastal and oceanic habitats. Tracking devices have shown that the whale shark displays dynamic patterns of habitat utilization, likely in response to availability of prey. Whale sharks observed off

4320-404: The dark stripes down its body, which resemble a tiger 's pattern, but fade as the shark matures. The tiger shark is a solitary, mostly nocturnal hunter. It is notable for having the widest food spectrum of all sharks, with a range of prey that includes crustaceans , fish , seals , birds , squid , turtles , sea snakes , dolphins , and others, even smaller sharks. It also has a reputation as

4410-416: The deep ocean. One of these mutations also makes rhodopsin vulnerable to higher temperatures. In humans, a similar mutation leads to congenital stationary night blindness , as the human body temperature makes the pigment decay. This pigment becomes unstable in shallow water, where the temperature is higher and the full spectrum of light is present. To protect from this instability, the whale shark deactivates

4500-552: The earlier stages of life but ultimately reach a smaller maximum size. Whale sharks exhibit late sexual maturity. One study looking at free-swimming whale sharks estimated the age at maturity in males at ~25 years. Pupping of whale sharks has not been observed, but mating has been witnessed twice in St Helena . Mating in this species was filmed for the first time in whale sharks off Ningaloo Reef via airplane in Australia in 2019, when

4590-658: The entire whale shark population. It usually roams between 30°N and 35°S where water temperatures are higher than 21 °C (70 °F) but have been spotted as far north as the Bay of Fundy , Canada and the Sea of Okhotsk north of Japan and as far south as Victoria, Australia . Seasonal feeding aggregations occur at several coastal sites such as the Persian Gulf and Gulf of Oman , Ningaloo Reef in Western Australia, Darwin Island in

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4680-454: The female retains sperm from one mating and produces a steady stream of pups over a prolonged period. On 7 March 2009, marine scientists in the Philippines discovered what is believed to be the smallest living specimen of the whale shark. The young shark, measuring only 38 cm (15 in), was found with its tail tied to a stake at a beach in Pilar, Sorsogon , Philippines, and was released into

4770-433: The filter pad surface, not perpendicularly through it, before passing to the outside, while denser food particles continue to the back of the throat. This is an extremely efficient filtration method that minimizes fouling of the filter pad surface. Whale sharks have been observed "coughing", presumably to clear a build-up of particles from the filter pads. Whale sharks migrate to feed and possibly to breed. The whale shark

4860-459: The first half of the year. There were a total 168 sightings – 64 of them "re-sightings" or reappearances of previously recorded whale sharks. WWF noted that "very young whale shark juveniles" were identified among the 168 individuals spotted in the first half of 2019. Their presence suggests that the Ticao Pass may be a pupping ground for whale sharks, further increasing the ecological significance of

4950-427: The fish swims forward at constant speed with its mouth fully open, straining prey particles from the water by forward propulsion. This is also called ‘passive feeding’, which usually occurs when prey is present at low density. Due their mode of feeding, whale sharks are susceptible to the ingestion of microplastics . As such, the presence of microplastics in whale shark scat was recently confirmed. Despite its size,

5040-413: The following year. The name "whale shark" refers to the animal's appearance and large size; it is a fish, not a mammal , and (like all sharks) is not closely related to whales . Whale sharks possess a broad, flattened head with a large mouth and two small eyes located at the front corners. Unlike many other sharks, whale shark mouths are located at the front of the head rather than on the underside of

5130-544: The following year. In the Southern Hemisphere, mating takes place in November, December, or early January. The tiger shark is the only species in its family that is ovoviviparous ; its eggs hatch internally and the young are born live when fully developed. Tiger Sharks are unique among all sharks in the fact that they employ embrytrophy to nourish their young inside the womb. The young gestate in sacks which are filled with

5220-438: The head. A 12.1 m (39.7 ft) whale shark was reported to have a mouth 1.55 m (5.1 ft) across. Whale shark mouths can contain over 300 rows of tiny teeth and 20 filter pads which it uses to filter feed . The spiracles are located just behind the eyes. Whale sharks have five large pairs of gills . Their skin is dark grey with a white belly marked with an arrangement of pale grey or white spots and stripes that

5310-700: The heads on juvenile tiger sharks are more conical and similar to other requiem sharks , adult tiger sharks have a head which is relatively broader. The reason for the larger caudal fin on juvenile tiger sharks is theorized to be an adaptation to escape predation by larger predators and to catch quicker-moving prey. As tiger sharks mature, their head also becomes much wider and their tails no longer become as large in proportion to their body size as when they are juveniles because they do not face elevated levels of predation risk upon maturity. The results of this study were interpreted as reflecting two ecological transitions: as tiger sharks mature they become more migratory and having

5400-536: The intricate web of interdependence among plants, animals, elements, and humans, underscoring the imperative to honor and coexist harmoniously with nature. Carcharhiniformes Carcharhiniformes / k ɑːr k ə ˈ r aɪ n ɪ f ɔːr m iː z / , the Requiem sharks , are the largest order of sharks , with over 270 species. They include a number of common types, such as catsharks , swellsharks , and requiem sharks . Members of this order are characterized by

5490-417: The land and in the water. When on land, the total length measurement can be affected by how the tail is positioned, either angled as it would be in life or stretched as far as possible. Historically, techniques such as comparisons to objects of known size and knotted ropes have been used for in-water measurements, but these techniques may be inaccurate. Various forms of photogrammetry have been used to improve

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5580-418: The largest known extant fish species . The largest confirmed individual had a length of 18.8 m (61.7 ft). The whale shark holds many records for size in the animal kingdom, most notably being by far the most massive living non-cetacean animal. It is the sole member of the genus Rhincodon and the only extant member of the family Rhincodontidae , which belongs to the subclass Elasmobranchii in

5670-413: The length of their sides. The primary role of this structure is to detect minute vibrations in the water. These adaptations allow the tiger shark to hunt in darkness and detect hidden prey. Sharks do not have moveable upper or lower eyelids, but the tiger shark—among other sharks—has a nictitating membrane , a clear eyelid that can cover the eye. A reflective layer behind the tiger shark's retina , called

5760-511: The most reliable seasonal gatherings known for whale sharks, with large numbers occurring in most years between May and September. Associated ecotourism has grown rapidly to unsustainable levels. Growth, longevity, and reproduction of the whale shark are poorly understood. Vertebral growth bands have been used to estimate the age, growth, and longevity of whale sharks. However, there was uncertainty as to whether vertebrae growth bands are formed annually or biannually. A 2020 study compared

5850-418: The mouth, or by active suction feeding, in which the animal opens and closes its mouth, sucking in volumes of water that are then expelled through the gills. In both cases, the filter pads serve to separate food from water. These unique, black sieve-like structures are presumed to be modified gill rakers . Food separation in whale sharks is by cross-flow filtration , in which the water travels nearly parallel to

5940-477: The northeast Yucatan Peninsula tend to engage in inshore surface swimming between sunrise and mid-afternoon, followed by regular vertical oscillations in oceanic waters during the afternoon and overnight. About 95% of the oscillating period was spent in epipelagic depths (<200 metres (660 ft)), but whale sharks also took regular deep dives (>500 metres (1,600 ft)), often descending in brief "stutter steps", perhaps for foraging. The deepest recorded dive

6030-499: The other, suggesting a total length of about 55 ft (17 m). Scott A. Eckert & Brent S. Stewart reported on satellite tracking of whale sharks from 1994 to 1996. Out of the 15 individuals tracked, two females were reported as measuring 15 m (49 ft) and 18 m (59 ft). A 20.75 m (68.1 ft) long whale shark was reported as being stranded along the Ratnagiri coast in 1995. A female individual with

6120-405: The pigment when in shallow water (as otherwise the pigment would hinder full color vision). In the colder environment at 2,000 meters below the surface where the shark dives, it is activated again. The mutations thus allow the shark to see well at both ends of its great vertical range. The eyes have also lost all cone opsins except LWS. The whale shark is the largest non- cetacean animal in

6210-564: The presence of a nictitating membrane over the eye, two dorsal fins , an anal fin , and five gill slits. The families in the order Carcharhiniformes are expected to be revised; recent DNA studies show that some of the conventional groups are not monophyletic . The oldest members of the order appeared during the Middle-Late Jurassic , which have teeth and body forms that are morphologically similar to living catsharks . Carchariniformes first underwent major diversification during

6300-515: The ratio of Carbon-14 isotopes found in growth bands of whale shark vertebrae to nuclear testing events in the 1950–60s, finding that growth bands are laid down annually. The study found an age of 50 years for a 10 m (33 ft) female and 35 years for a 9.9 m (32 ft) male. Various studies looking at vertebrae growth bands and measuring whale sharks in the wild have estimated their lifespans from ~80 years and up to ~130 years. Evidence suggests that males grow faster than females in

6390-626: The region they inhabit, with some growing close to twice as fast as others. Among the largest extant sharks, the tiger shark ranks in average size only behind the whale shark ( Rhincodon typus ), the basking shark ( Cetorhinus maximus ), and the great white shark ( Carcharodon carcharias ). This makes it the second-largest predatory shark, after the great white. Some other species such as megamouth sharks ( Megachasma pelagios ), Pacific sleeper sharks ( Somniosus pacificus ), Greenland sharks ( Somniosus microcephalus ), and bluntnose sixgill sharks ( Hexanchus griseus ) broadly overlap in size with

6480-435: The shark matures. Its head is somewhat wedge-shaped, which makes it easy to turn quickly to one side. They have small pits on the snout which hold electroreceptors called the ampullae of Lorenzini , which enable them to detect electric fields, including the weak electrical impulses generated by prey, which helps them to hunt. Tiger sharks also have a sensory organ called a lateral line which extends on their flanks down most of

6570-482: The shark's life. Relative to the shark's size, tiger shark teeth are considerably shorter than those of a great white shark, but they are nearly as broad as the root as the great white's teeth and are arguably better suited to slicing through hard-surfaced prey. A tiger shark generally has long fins to provide lift as the shark maneuvers through water, while the long upper tail provides bursts of speed. The tiger shark normally swims using small body movements. The skin of

6660-425: The small catsharks and hammerhead sharks . Members of this order are characterized by the presence of a nictitating membrane over the eyes, two dorsal fins, an anal fin , and five gill slits. It is the largest member of the order, commonly referred to as ground sharks . It is the only extant member of Galeocerdo , the only member of the family Galeocerdonidae. The oldest remains of Galeocerdo extend back to

6750-614: The source. The ability to pick up low-frequency pressure waves enables the shark to advance towards an animal with confidence, even in murky water. The shark circles its prey and studies it by prodding it with its snout. When attacking, the shark often eats its prey whole, although larger prey are often eaten in gradual large bites and finished over time. Notably, terrestrial mammals, including horses ( Equus ferus caballus ), goats ( Capra aegagrus hircus ), sheep ( Ovis aries ), dogs ( Canis lupus familiaris ), cats ( Felis catus ), and brown rats ( Rattus norvegicus ), are fairly common in

6840-560: The stomach contents of tiger sharks around the coasts of Hawaii. In one case, remains of two flying foxes were found in the stomach of this shark, and in another, an echidna ( Tachyglossus aculeatus ) was regurgitated by a tiger shark being tagged off Orpheus Island , Queensland . Because of its aggressive and indiscriminate feeding style, it often mistakenly eats inedible objects, such as automobile license plates , oil cans, tires , and baseballs . Due to their habits of eating essentially anything, Tiger sharks are often referred to as

6930-455: The strongest swimmers of the carcharhinid sharks. Once the shark has come close, a speed burst allows it to reach the intended prey before it can escape. Males reach sexual maturity at 2.3 to 2.9 m (7.5 to 9.5 ft) and females at 2.5 to 3.5 m (8.2 to 11.5 ft). Typical weight of relatively young sexually mature specimens, which often locally comprise the majority of tiger sharks encountered per game-fishing and scientific studies,

7020-692: The three largest species: the leatherback ( Dermochelys coriacea ), the loggerhead ( Caretta caretta ) and the green sea turtles ( Chelonia mydas )), are regularly eaten by adult tiger sharks. In fact, adult sea turtles have been found in up to 20.8% of studied tiger shark stomachs, indicating somewhat of a dietary preference for sea turtles where they are commonly encountered. They also eat other sharks (including adult sandbar sharks ( Carcharhinus plumbeus )), as well as rays , and sometimes even other tiger sharks . Due to high risk of predation, dolphins often avoid regions inhabited by tiger sharks. Injured or ailing whales may also be attacked and eaten. A group

7110-772: The tiger shark, but as these species are comparatively poorly studied, whether their typical mature size matches that of the tiger shark is unclear. The great hammerhead ( Sphyrna mokarran ), a member of the same taxonomic order as the tiger shark, has a similar or even greater average body length, but is lighter and less bulky, with a maximum known weight coming from a heavily pregnant 4.4 m (14 ft) long individual at 580 kg (1,280 lb). Tiger shark teeth are unique with very sharp, pronounced serrations and an unmistakable sideways-pointing tip. Such dentition has developed to slice through flesh, bone, and other tough substances such as turtle shells. Like most sharks, its teeth are continually replaced by rows of new teeth throughout

7200-404: The upper portion of the growth curves. The largest total length for the species is uncertain due to a lack of detailed documentation of the largest reported individuals. Whale sharks as large as 18 to 20 meters (59 to 66 ft) in length have been reported in scientific literature. However, most whale sharks observed are smaller. Large whale sharks are difficult to measure accurately, both on

7290-713: The western Pacific Ocean , the shark has been found as far north as Japan and as far south as New Zealand . It has also been recorded in the Mediterranean Sea , but rarely, off Malaga (Spain), Sicily (Italy) and Libya. Tiger sharks can be seen in the Gulf of Mexico , North American beaches, and parts of South America. It is also commonly observed in the Caribbean Sea . Other locations where tiger sharks are seen include off Africa, China, India , Australia , and Indonesia . Certain tiger sharks have been recorded at depths just shy of 900 m (3,000 ft). The tiger shark

7380-413: The whale shark does not pose any danger to humans. Younger whale sharks are gentle and can play with divers. Underwater photographers such as Fiona Ayerst have photographed them swimming close to humans without any danger. Although whale sharks are docile fish, touching or riding the sharks is strictly forbidden and fineable in most countries, as it can cause serious harm to the animal. The shark

7470-528: The wild. Based on this discovery, some scientists no longer believe this area is just a feeding ground; this site may be a birthing ground, as well. Both young whale sharks and pregnant females have been seen in the waters of St Helena in the South Atlantic Ocean, where numerous whale sharks can be spotted during the summer. In a report from Rappler last August 2019, whale sharks were sighted during WWF Philippines ' photo identification activities in

7560-532: The world. However, the maximum size and growth patterns of the species are not well understood. Limited evidence, mostly from males, suggests that sexual maturity occurs around 8 to 9 meters (26 to 30 ft) in length, with the possibility of females sexually maturing at a similar size or larger. Various studies have aimed to estimate the growth and longevity of whale sharks, either by analysing evidence from vertebral growth rings or measurements taken from re-sighted sharks over several years. This information

7650-488: Was 1,928 metres (6,325 ft), making the whale shark the deepest diving fish to be recorded. Whale sharks were also observed to remain continuously at depths of greater than 50 metres (160 ft) for three days or more. The whale shark is migratory and has two distinct subpopulations: an Atlantic subpopulation, from Maine and the Azores to Cape Agulhas , South Africa, and an Indo-Pacific subpopulation which holds 75% of

7740-493: Was documented killing an ailing humpback whale ( Megaptera novaeangliae ) in 2006 near Hawaii. A scavenger, the tiger shark will feed on dead whales, and has been documented doing so alongside great white sharks. Tiger sharks have also been observed to feed on dead manta rays in the German Channel of Palau. Evidence of dugong predation was identified in one study that found dugong tissue in 15 of 85 tiger sharks caught off

7830-514: Was first described by Peron and Lesueur in 1822, and was given the name Squalus cuvier . Müller and Henle in 1837 renamed it Galeocerdo tigrinus . The genus, Galeocerdo , is derived from the Greek galeos , which means shark, and kerdo , the word for fox. It is often colloquially called the man-eater shark. The tiger shark is a member of the order Carcharhiniformes , the most species-rich order of sharks, with more than 270 species also including

7920-704: Was included. The authors noted that these estimates represent average asymptotic size and are not the maximum sizes possible. Additionally, they acknowledged the potential for regional size variation. Most previous growth studies have had data predominately from males and none have data from sharks over ~10 m (33 ft). Not all previous studies created separate growth curves for males and females, instead combining data from both sexes. Those studies that made sex-specific growth curves have estimated large asymptotic length estimates for males, with lengths of 18 m (59 ft) or more. However, mostly immature males were available in these studies, with few adults to constrain

8010-559: Was kept for about four months in a netted-off natural bay in Izu , Japan. The first attempt of keeping whale sharks in an aquarium was initiated in 1980 by the Okinawa Churaumi Aquarium (then known as Okinawa Ocean Expo Aquarium) in Japan. Since 1980, several have been kept at Okinawa, mostly obtained from incidental catches in coastal nets set by fishers (none after 2009), but two were strandings. Several of these were already weak from

8100-497: Was told of specimens upwards of 70 ft (21 m). Hugh M. Smith described a huge animal caught in a bamboo fish trap in Thailand in 1919. The shark was too heavy to pull ashore, and no measurements were taken. Smith learned through independent sources that it was at least 10 wa (a Thai unit of length measuring between a person's outstretched arms). Smith noted that one wa could be interpreted as either 2 m (6.6 ft) or

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