The tiger shark commonly attains a length of 3.25–4.25 m (10 ft 8 in–13 ft 11 in) and weighs around 385–635 kg (849–1,400 lb). It is dimorphic, with exceptionally large females reportedly measuring 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 900 kg (2,000 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.
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). 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 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 of 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 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. Its high back and dorsal fin act as a pivot, allowing it to spin quickly on its axis, though the shark's dorsal fins are distinctively close to its tail.
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The tiger shark is a fish that prefers to live alone unless it is in the mating period. During that time it meets with other tiger sharks and groups establishing a social hierarchy based on their size, so larger individuals have access to prey before than the small ones. Once the elders are satisfied, the others can approach the carcasses of the unfortunate prey. Despite this dominating behavior, violence between members is almost nil. These sharks perform their hunting activities during the nights, and because of their indiscriminate eating habits, they usually ingest non-edible objects and tastes human flesh, although attacks are rare.
The tiger shark is an apex predator and has a reputation of having an enormous appetite and can eat almost anything they find in their path. The tiger shark diet is made up of fish, mollusks, crustaceans, sea turtles, seabirds and even mammals such as the dugong. It also consumes small sharks and the remains of dead whales or can even venture to attack the wounded and immobile cetaceans. That is why, if they run into non-edible objects or junk, they do not hesitate to eat them even without trying them first. In their stomachs trash, bags, and even license plates have been found. They can camouflage with the environment and thus easily trap their prey. However, these sharks have one disadvantage: if their victim begins to flee, they recoil and do not pursue it since they do not engage in high-speed chases. Although they have a reputation as a ferocious predator, they can survive several weeks without anything to eat.
Both male and female have multiple sexual partners throughout their life, which is about 27 years in the wild. The female reaches sexual maturity around eight years old and the male at seven years old. There is little information about the existence of a process of courtship. It is known that the female mates once every three years and reproduces through ovoviviparity. Fertilization occurs in different seasons in the southern hemisphere and the northern hemisphere. In the first, fertilization occurs between March and May and in the latter occurs between November and January. The embryos develop inside the uterus and feed on the yolk sac and the secretions produced by the uterus. After 14-16 months the female gives birth to about 10-82 fully developed offspring which can survive without the help of the parents.
In Maldives it is banned catching, keeping in captivity, trading or harming any species of shark under the Environmental Protection and Preservation Act (Ministry of Housing and Environment Iu’laan 138/1/2011/42).
Lately in Maldives, scuba diving with tiger shark have gained in popularity in tourism industry. Islands such as in Fuvahmulah, divers can see dozens of Tiger sharks everyday.
The Tiger Shark inhabits shelf, reef, and slope habitats, is sometimes associated with coral reefs, and occasionally makes longer-distance excursions into the pelagic zone. The species mostly occurs to 100 m depth but also dives to depths greater than 1,000 m (1,136 m maximum recorded) and has been noted to move hundreds, and in some cases thousands, of kilometres (Holmes et al. 2014, Werry et al. 2014, Afonso and Hazin 2015, Lea et al. 2015).
The species has a higher intrinsic rate of population increase than many other carcharhinid sharks (Dudley and Simpfendorfer 2006). Growth rates during early life stages are thought to be high (Branstetter et al. 1987). Maximum recorded size is 740 cm total length (TL) but individuals larger than 500 cm TL are rarely seen (Ebert et al. 2013). There is regional variability in sizes and ages at maturity with females mature at 274-345 cm TL and males at 250-305 cm TL (Compagno 1984, Randall 1992, Simpfendorfer 1992, Wintner and Dudley 2000, Whitney and Crow 2007, Holmes et al. 2015). The maximum age is estimated at 27-37 years (Natanson et al. 1999, Kneebone et al. 2008, Holmes et al. 2015), with age at maturity of 4-13 years (Branstetter et al. 1987, Smith et al. 1998, Natanson et al. 1999, Afonso et al. 2012, Meyer et al. 2014, Holmes et al. 2015). Based on data from the Western North Atlantic (Natanson et al. 1999) and Australia (Holmes et al. 2015), the generation length is estimated at 17.5-22.5 years.
The Tiger Shark is the only species of the family Carcharhinidae that is lecithotrophic viviparous. Litter sizes are large, with a maximum of 82 embryos records and an average litter size of 26-33 pups (Tester 1969, Bass et al. 1975, Simpfendorfer 1992). The size at birth is 51-90 cm TL (Randall 1992, Simpfendorfer 1992). Gestation is approximately 15-16 months with a triennial reproductive cycle in Hawaii and Australia (Whitney and Crow 2007, Holmes 2015).
Globally, the Tiger Shark is caught is taken in target shark fisheries and as bycatch in commercial and artisanal fisheries. The species is subject to illegal, unreported, and unregulated (IUU) fishing operations and is regularly caught in recreational fisheries. This species is also targeted by shark control programs in Australia (Paterson 1990, Reid et al. 2011), South Africa (Dudley and Simpfendorfer 2006, Cliff and Dudley 2011), and more recently Reunion Island in the Western Indian Ocean. The species has been increasingly exploited by fisheries since the 1950s (Ward-Paige et al. 2010) due to the increasing demand from the shark fin trade. Catches of Tiger Shark in directed shark fisheries have been documented for a number of regions including the western Atlantic (Hoey and Casey 1986, Berkeley and Campos 1988, Bonfil 1994, Morgan et al. 2009, Carlson et al. 2012), Brazil (Bonfil 1994), Australia (Stevens et al. 1982, Lyle et al. 1984, Macbeth et al. 2009, Tillett et al. 2012), Papua New Guinea (Kumoru 2013), Peru (Gonzalez-Pestana et al. 2014), Taiwan (Bonfil 1994), India (Bineesh et al. 2014), and Saudi Arabia (Spaet and Berumen 2015).
The Tiger Shark is a common component of the U.S. east coast/Gulf of Mexico commercial shark bottom longline fishery, accounting for 8-36% of the catch (Morgan et al. 2009, Carlson et al. 2012). The fishery catches mostly juvenile and subadult Tiger Sharks, although some larger sharks are also taken. In Australia, the Tiger Shark is targeted by commercial shark fisheries in northern New South Wales and in Western Australia. The species accounted for 3 tonne (t) and 5.9% of total catch of the Ocean Trap and Line Fishery in eastern Australia. However, catches by this fishery are probably smaller than landings from recreational fisheries in that same area (Park 2007, Macbeth et al. 2009). In the Western Australia Tropical Shark Fishery, this shark was caught as a target species and annual catches averaged approximately 41 t between 2000 and 2004. This fishery was closed in late 2005 (Department of Fisheries 2005). The Tiger Shark is relatively common in the Indonesian shark fishery and contributed 5.2% of the total shark biomass of catches from between 2001 and 2006 (White 2007). The Tiger Shark is also commonly caught in the seamount gillnet and longline fishery off the west coast of India, where 242 t and 144 t of various shark species were taken during 2010 and 2011, respectively, but species-specific catches were not recorded (Bineesh et al. 2014). The Offshore Net and Line Fishery operating in the northern Australia catches the species incidentally (27 t in 2012), although mesh size is assumed to prevent capture of greater numbers (Lyle et al. 1984, DPFI 2012). This shark is also taken in the Southern and Western Demersal Gillnet and Demersal Longline Fishery in Western Australia with a catch of 112 t reported in 2005-06 (McAuley 2008). The Tiger Shark is a bycatch in trawl fisheries although normally in small numbers and there are few records of catches for these fisheries. The Australian Commonwealth Trawl Sector reported a total catch for the species of 4.7 t from 2004-2011. The Tiger Shark is caught occasionally in the longline fisheries of Costa Rica (Dapp et al. 2013), Mozambique (Sousa 2012), and Saudi Arabia (Spaet and Berumen 2015) and by purse seiners in the Indian Ocean (Chassot et al. 2014). Although little species-specific catch data information is available for the Arabian Seas area, the high level of level of fishing pressure in the region is of concern with steep increases in both small-scale and industrial fishing effort between the 1990s and 2000s (PERSGA 2002, Tsehaye et al. 2007, Bruckner et al. 2011, Valinassab et al. 2006, Jabado et al. 2015, Jabado et al. 2017).
In tuna longline fisheries, the species is typically caught in small numbers relative to pelagic sharks and is often not reported. Between 2007 and 2013, an average of 54 t was landed annually by tuna longline boats regulated by the International Commission for the Conservation of Atlantic Tuna (ICCAT database, P. de Bruyn, pers. comm. 2015). Tiger Shark represented less than 10% of the total bycatch of all shark species in each of the management zones of the U.S. pelagic longline fishery (Mandelman et al. 2008). In the Panama longline fishery, the Tiger Shark represented 1.6% of shark catches of the estimated total catch of 109,500 t of various sharks since the mid-1980s (Harper et al. 2014). In the Central and Western Pacific, the Tiger Shark is caught in low numbers (0.025 sharks per set; P. Williams, pers. comm. 2015) by tuna longline boats from most countries operating in that region.
The Tiger shark is a common target of recreational fisheries in the United States, Australia, and South Africa. Approximately 96% of the catch in USA waters are released alive. In the New South Wales Gamefish Tournament, Tiger Shark catches were approximately 8 t per year between 1993 and 2005 (Park 2007). Recreational fishing may account for mortality in the Tiger Shark population in other countries, although catches are unmonitored.
Artisanal fisheries and IUU fisheries are also likely to be catching Tiger Shark, however information about landings from these fisheries is scarce as they remain mostly unmonitored. The Tiger Shark is commonly caught in artisanal fisheries in the tropics and subtropics, including in Mexico (Ramirez-Amaro et al. 2013), Panama (Harper et al. 2014), Brazil (Bornatowski et al. 2014, Pimenta et al. 2014), and a few African countries (FAO 2014). In Bangladesh, landings of 4.5 t represent on average 1.36% of total catch (Jit et al. 2014). There is evidence that the species has been overfished by Indonesian fishing boats at Ashmore and Cartier Islands, and Scott Reef in northern Australian waters. This area had been targeted by Indonesian fishermen since the 1800s but fishing was banned in 1988 and 2000, respectively (Field et al. 2009). A survey in the region showed the absence of Tiger Shark at reefs historically fished despite years of protection whereas they were found present at nearby atolls that had been always protected from fishing (Meekan et al. 2006). The species comprised 19% of the total shark biomass and 7.4% of total catch in numbers from Indonesian and Taiwanese IUU fishing vessels (Marshall 2011).
The Tiger Shark is a target species of shark control programs in Queensland (Paterson 1990, Holmes et al. 2012) and New South Wales, Australia (Reid et al. 2011), in South Africa (Dudley and Simpfendorfer 2006, Cliff and Dudley 2011), and more recently at Reunion Island. In Australia, the Queensland Shark Control Program (QSCP) captured 4,757 Tiger Shark individuals between 1993 and 2010 (Holmes et al. 2012) and the species represented approximately 10 to 30% of total catch in the northern locations of the QSCP between 1964 and 2007 (Simpfendorfer et al. 2010). Standardized catch rates from 1964-2007 for the QSCP in northern Queensland showed an increase in the relative importance of the Tiger Shark, from approximately 10 to 30% of total catch. This pattern is most likely due to the move in fishing gear from nets to drumlines (Simpfendorfer et al. 2010). In southeast Australia, the Tiger Shark was commonly captured by the New South Wales Shark Meshing Program from 1950-2010 with approximately 30 sharks per year between 1950 and 2008, representing approximately 10% of the common shark species caught by the program in each of its locations (Reid et al. 2011). In South Africa, the KwaZulu-Natal beach protection program has caught approximately 50 individuals annually from 1978-2003. Since 1989, sharks caught alive are released; however, fishing mortality of the Tiger Shark in nets is 27% of captures (Dudley and Simpfendorfer 2006).