| ||Squalus americanus Mitchill, 1815, (not S. americanus Gmelin, 1789 = Dalatias licha).|
| ||Squalus littoralis Le Sueur, 1818|
| ||Squalus macrodus Mitchell, 1817|
| ||Carcharias griseus Ayres, 1843|
| ||Odontaspis americanus Abbott, 1861|
| ||? Odontaspis cinerea Macleay, 1880, (nomen nudum).|
| ||Lamna ecarinata Hemprich & Ehrenberg, 1899|
| ||Carcharias arenarius Ogilby, 1911|
| ||Carcharias owstoni Garman, 1913|
| ||? Squalus lixa Larranaga, 1923|
| ||Odontaspis platensis Lahille, 1928|
| ||Odontaspis taurus Rafinesque, 1810|
| ||Carcharias platensis Lahille, 1928|
|En - Sand tiger shark, Fr - Requin taureau, Sp - Toro bacota.|
3Alpha Code: CCT Taxonomic Code: 1060200501|
|Scientific Name with Original Description|
|Carcharias taurus Rafinesque, 1810. Caratt. gen. sp. anim. piant. Sicilia, Palermo, pt. 1:10, pl. 14, fig. 1. Holotype: Unknown. Type Locality: Sicily, Mediterranean Sea.|
Snout short and somewhat flattened; eyes small;
three rows of large upper anterior teeth and usually no symphyseal teeth on each side of symphysis; posterior teeth well differentiated from lateral teeth, with cusps and cusplets reduced or absent, molariform.
First dorsal base closer to pelvic bases than to pectoral bases, with its origin well behind inner margins of pectorals and its insertion about over pelvic origins; second dorsal fin about as large as first dorsal; anal fin about as large or slightly larger than dorsal fins and with its origin under midbase of second dorsal.
|fieldmarks: A large, bulky shark. Head with a flattened-conical snout, eyes without nictitating eyelids, mouth long and extending behind eyes, teeth large, with prominent narrow cusps and lateral cusplets, upper anterior teeth separated from lateral teeth by small intermediate teeth. Anal fin and both dorsal fins equally large and broad-based, first dorsal fin on back closer to pelvic fins than pectorals, upper precaudal pit present but lateral keels absent from caudal peduncle, caudal fin asymmetrical but with a strong ventral lobe. Colour: light brown, often with darker reddish or brownish spots scattered on body.|
|Can be confused with: Included as synonyms of Carcharias taurusare a number of regional species that have often been considered valid in the older literature, but which are most likely local representatives of a single, wide-ranging species. The dental characters most often used to distinguish these species (see Bigelow & Schroeder, 1948) apparently vary considerably within samples from a given area (Applegate, 1965, Sadowsky, 1970, Taniuchi, 1970). These include Squalus americanusand its synonyms from the western North Atlantic, Odontaspis platensis from the western South Atlantic, Carcharias owstoni from the western North Pacific, and Carcharias arenarius from Australia. Abe et al. (1968, 1969), Sadowsky (1970), Taniuchi (1970), and Whitley & Pollard (1980) have all used the species name taurus for the local representatives of the species formerly named owstoni, arenarius, and platensis.|
|Western Atlantic: Gulf of Maine to Florida, northern Gulf of Mexico, Bahamas, Bermuda; southern Brazil to Argentina. Eastern Atlantic: Mediterranean to Canary Islands; Cape Verde Islands, Senegal, Ghana, southern Nigeria to Cameroon. Western Indian Ocean: South Africa to southern Mozambique; Red Sea, Pakistan, ?India. Western Pacific: ?Indonesia, ?VietNam, Japan, China; Australia (Queensland, New South Wales, Victoria, Tasmania, South Australia, Western Australia).|
|Habitat and Biology|
|This is a common littoral shark in temperate and tropical waters where it occurs.It ranges from the surf zone, in shallow bays, and around coral and rocky reefs down to at least 191 m depth. This species is often found near or on the bottom but also occurs in midwater or at the surface.It is a strong but slow midwater swimmer that is more active at night. This shark is denser than water, but it swallows air at the surface and holds it in its stomach to maintain approximately neutral buoyancy. Like a bony fish with a swimbladder, it is capable of hovering motionless in the water. It is a very hardy species that readily adapts to captivity and can live for many years and even give birth in adequate tank facilities. This species occurs as solitary individuals or in small to large schools. It is strongly migratory in parts of its range, particularly in its northern and southern extremities where pronounced poleward migrations occur in summer and equatorial movements in fall and winter. Aggregations of individuals occur for feeding, courtship, mating, and birth.|
Off South Africa courtship and mating apparently occurs in the more tropical parts of its range, while pregnant females give birth in warm-temperate waters. Reproduction in this species is better known than in most other lamnoids and features ovophagy or uterine cannibalism. There are normally two young in a litter, one per uterus. Eggs leave the ovaries, and while in transit in the oviducts are fertilized and enclosed in groups of 16 to 23 in egg cases. However, at some time between fertilization and birth only one embryo of its group prevails, possibly by devouring its rivals, and this proceeds to eat fertilized eggs and smaller potential siblings in utero until birth. Unlike ovoviviparous non-cannibal and viviparous species, the yolk sac is resorbed at a small size, less than 17 cm, and the umbilical scar may be lost. At 17 cm, fetuses have sharp, functional teeth and are feeding; at about 26 cm, they can swim in utero; size at birth is very large, about 1 m. The gestation period may be 8 to 9 months long.
This shark is a voracious feeder on a wide variety of bony fishes including herring, croakers, bluefish, bonito, butterfish, snappers, hake, eels, wrasses, mullet, spadefish, sea robins, sea basses, porgies, remoras, sea catfish, flatfish, jacks, and undoubtedly many others, as well as small sharks (Carcharhinidae and Triakidae ), rays (Myliobatidae ), squid, crabs and lobsters . Schools of this shark have been observed to feed cooperatively, surrounding and bunching schooling prey and then feeding on them.
|Maximum total length about 318 cm, mature males 220 to 257+ cm, mature females 220 to 300+ cm, size at birth 95 to 105 cm.|
|Interest to Fisheries|
|Generally fished in all areas where it is found, but of variable importance regionally;|
it is highly regarded for food in Japan but not in the western Atlantic.It is caught primarily with line gear but also fixed bottom gillnets, and in pelagic and bottom trawls .
The meat of this shark is utilized fresh, frozen, smoked and dried salted for human consumption; it is also used for fishmeal, its liver for oil, its fins for the oriental sharkfin trade.
Sand tiger sharks are easily targeted by fisheries because of their habit to form large mating aggregations at predictable times in specific coastal areas. This makes it possible for these sharks to be easily depleted in a relatively short time. They are also very docile and were senselessly killed in large numbers in the past in Australia by sport divers using power heads. Partly as a result of this habit, sandtigers in New South Wales entered the record books in 1984 as the first fully protected shark species in the world (Pollard 1996). The numbers of sandtiger sharks caught in the New South Wales beach netting decreased from an average of 30 per year in the 1951-1954 period to 1-2 per year in the 1988-1990 period (Stevens 1993; cited by Castroet al. in press). In the United States, Castro et al. (in press) report a severe population decline in the early 1990s, with sandtigers practically disappearing from North Carolina and Florida waters. Off the mouth of Chesapeake Bight in the U.S. Mid-Atlantic coast, sandtiger shark abundance dropped from 1 shark per 100 hooks average in the 1974-1979 period to 0.2 sharks per 100 hooks in 1991 (Musick et al. 1993).
Conservation Status : The sandtiger shark has a mid-range intrinsic rebound potential (Smith et al. 1998) suggesting it would not be extremely sensitive to fishing. However, there are at least two documented cases of strong declines in abundance due to excessive fishing (see impact of fisheries section) which might be related to this shark's habit to form easily-targeted mating aggregations. According to the IUCN Red List the sandtiger shark is considered Vulnerable at the world level and Endangered in the NW Atlantic and in Eastern Australia (Camhiet al. 1998). Sandtiger sharks are protected by law and cannot be killed or captured in New South Wales, Queensland, and all Australian Commonwealth waters, and also in all federal waters of the USA coasts of the Gulf of México and the Atlantic Ocean.
Additional information from IUCN database
Additional information from CITESdatabase
|Threat to humans: As the "grey nurse" shark, this species has a bad reputation as a man-eater in Australian waters, but this is apparently due to confusion with other species, particularly requiem sharks (Carcharhinidae). Observations of this shark underwater suggest that it is primarily inoffensive and unaggressive towards people when not provoked, though its size and jagged dentition should invite respect. However, it can be stimulated to harass and attack people, particularly when they are spearfishing. Cases are known of this shark stealing fish off stringers and spears underwater, underlining the desirability of boating one's catch as soon as possible when this shark or others are about. Relatively few documented attacks by this shark on people have been reported. On the other hand, divers armed with powerheads and other underwater weapons have found this slow-moving species an easy target in some areas (particularly Australia); such crude and barbaric 'sport', analogous to shooting domestic cattle with a pistol, has caused a decline in the number of these sharks where it occurs.|
Bass, D'Aubrey & Kistnasamy, (1975)
Bigelow & Schroeder, (1948)
Lineaweaver & Backus, (1970)