Tiger Shark. Galeocerdo cuvier NE ATL TIG. Lateral View ( ) Ventral View ( ) APPEARANCE Very short, blunt snout with large subterminal mouth.

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1 Lateral View ( ) Ventral View ( ) APPEARANCE Very short, blunt snout with large subterminal mouth. SYNONYMS Body more slender behind pectoral fins. DISTRIBUTION The Tiger Shark is found circumglobally in tropical and temperate waters. In the northeast Atlantic it is probably wide ranging and has been confirmed from Morocco, the Canary Isles, Senegal, Gambia, No Records Guinea, the Ivory Occasional Coast and Ghana. Range There is a record from Iceland, presumably a vagrant (Compagno, 1984). Map base conforms with ICES grid squares. Interdorsal ridge present. Anal fin strongly recurved. NE ATL Slender caudal fin with acutely pointed tip. Dark, vertical, tiger-stripe markings, faded on older specimens. Bluish-green to dark grey or black dorsally. Normally to a maximum of 550cm. Unconfirmed reports to 910cm. A highly distinctive shark, adults are unlikely to be confused with other Carcharhinids as it grows seven times larger than any other species in the family (Martin, Unknown). The head is large and broad, as is the subterminal mouth. The eyes and spiracles are also large (Compagno, 1984). The spiracles are slit-like, a unique trait among Carcharhinids (Martin, Unknown). Behind the pectoral fins the body becomes thinner to a slender caudal fin with an acutely pointed tip. There is an interdorsal ridge and the anal fin is strongly recurved (Compagno, 1984). The gets its common name from the dark stripes running vertically along its back. These are prominent in younger individuals but fade with age. The background dorsal colouration is bluish-green to dark grey or even black. It is ventrally white or yellowwhite (Knickle, Unknown). The maximum reported size is 740cm from a female caught off Indo-China. Normally, it does not exceed 550cm although there are anecdotal reports of individuals to 910cm (Compagno, 1984) NT Squalus cuvier (Péron & LeSueur, 1822), Squalus arcticus (Faber, 1829), Galeus cepedianus (Agassiz, 1838), Galeocerdo tigrinus (Müller & Henle, 1839), Galeus maculatus (Ranzani, 1840), Carcharias (Prionodon) fasciatus (Bleeker, 1852), Galeocerdo rayneri (McDonald & Barron, 1868), Galeocerdo obtusus (Klunzinger, 1871), Carcharias hemprichii (Hilgendorf, in Hemprich & Ehrenberg, 1899). Long labial furrows which reach eyes. Large spiracles. TIG COMMON NAMES, Leopard Shark, Maneater Shark, Spotted Shark, Requin Tigre Commun (Fr), Tintorera (Es).

2 Supported by: SIMILAR SPECIES Carcharhinus longimanus, Oceanic Whitetip Shark Carcharhinus plumbeus, Sandbar Shark Carcharhinus brachyurus, Copper Shark Carcharhinus falciformis, Silky Shark, Carcharhinus longimanus, Oceanic Whitetip Shark Carcharhinus plumbeus, Sandbar Shark Carcharhinus brachyurus, Copper Shark Carcharhinus falciformis, Silky Shark (Not to scale)

3 TEETH The upper and lower teeth are similar in shape and size, having curved cusps and serrated edges. Each has a deep notch on the outer margin and is lined with numerous cusplets. They decrease in size but stay relatively similar towards the corners of the mouth (Knickle, Unknown). ECOLOGY AND BIOLOGY HABITAT The is known from a wide variety of habitats but generally prefers turbid coastal waters, commonly estuaries, harbours, lagoons and other inlets where nutrient run-off may increase the availability of prey. It can be found from the surface to at least 350m. Capable of long migrations, it is known to move into cooler waters during the warmer months and back into warmer areas during the colder months. It can also travel long distances between oceanic islands in short amounts of time (Knickle, Unknown). Diurnal migrations are known to occur with some tagged sharks moving inshore at night. This was not observed in a Hawaiian tagging project (Holland et al., 1999). EGGCASE N/A DIET The is a predator and scavenger that has one of the widest and most variable diets of any shark. This includes teleost fish, elasmobranchs, marine reptiles, seabirds (including migrating land birds), marine mammals, molluscs, crustaceans, gastropods, tunicates and carrion. It has also earned a reputation as a garbage can with fins due to the vast number of different inedible items found among its stomach contents, including leather, fabrics, pieces of coal and wood, seeds and other vegetable material, feathers, plastic bags, burlap bags, small barrels, cans and pieces of metal (Compagno, 1984). REPRODUCTION Females reach maturity at a length of cm, males at a length of cm (Knickle, Unknown). It is the only species in the Carcharhinidae family that reproduces ovovivipariously which, along with other factors, has lead some researchers to suggest that it be placed in its own family (Martin, Unknown). The gestation period is months and litters of have been reported (Knickle, Unknown; Compagno, 1984).

4 Supported by: COMMERCIAL IMPORTANCE Relatively common worldwide, the is taken in target fisheries and as bycatch throughout its range. Its meat, fins, liver oil and hide can all be utilised (Simpfendorfer, 2000). Its jaws and teeth are highly valuable in the curio trade and it is also a popular game fish due to its large size and ferocious reputation (Randall, 1992; Knickle, Unknown). These traits also make it a popular species for recreational divers seeking large sharks (Knickle, Unknown). IUCN RED LIST ASSESSMENT Near Threatened (2000). THREATS, CONSERVATION, LEGISLATION A relatively fast growing and highly fecund species, the Tiger Shark is more resilient to fishing pressure than many other large shark species. However, there is evidence from commercial and recreational anglers that declines have occurred in many areas where it is heavily fished, including the mid-atlantic. It has been reported that juvenile survival rates increase when adult populations drop due to fewer incidences of cannibalism (Simpfendorfer, 2000). HANDLING AND THORN ARRANGEMENT Handle with care. Sharp teeth. Abrasive skin.

5 REFERENCES COMPAGNO, L. J. V Sharks of the World: An Annotated and Illustrated Catalogue of Shark Species Known to Date. Volume 4, Part 1. Hexanchiformes to Lamniformes. FAO. Rome, Italy. HOLLAND, K. N., WETHERBEE, B. M., LOWE, C. G., MEYER, C. G Movements of tiger sharks () in coastal Hawaiian waters. Marine Biology. Vol. 134 (4): KNICKLE, C. Unknown.. Florida Museum of Natural History. MARTIN, R. A. Unknown. Family Carcharhinidae: Whaler Sharks. 54+ species. ReefQuest Centre for Shark Research. www. elasmo-research.org. RANDALL, J. E Review of the biology of the (). Australian Journal of Marine and Freshwater Research. Vo. 43 (1): SIMPFENDORFER, C In: IUCN IUCN Red List of Threatened Species. Version org. Text: Richard Hurst. Illustrations: Marc Dando. Citation Shark Trust; An Illustrated Compendium of Sharks, Skates, Rays and Chimaera. Chapter 1: The British Isles and Northeast Atlantic. Part 2: Sharks. Any ammendments or corrections, please contact: The Shark Trust 4 Creykes Court, The Millfields Plymouth, Devon PL1 3JB Tel: / enquiries@sharktrust.org For more ID materials visit Registered Company No Registered Charity No