School shark

Description

The school shark (Galeorhinus galeus) is a houndshark of the family Triakidae, and the only member of the genus Galeorhinus. Common names also include tope shark, snapper shark, and soupfin shark. It is found worldwide in temperate seas at depths down to about 800 m (2,600 ft). It can grow to nearly 2 m (6 ft 7 in) long. It feeds both in midwater and near the seabed, and its reproduction is ovoviviparous. This shark is caught in fisheries for its flesh, its fins, and its liver, which has a very high vitamin A content. The IUCN has classified this species as critically endangered in its Red List of Threatened Species. The school shark is a small, shallow-bodied shark with an elongated snout. The large mouth is crescent-shaped and the teeth are of a similar size and shape in both jaws. They are triangular-shaped, small, and flat, set at an oblique angle facing backwards, serrated and with a notch. The spiracles are small. The first dorsal fin is triangular with a straight leading edge and is set just behind the pectoral fins. The second dorsal fin is about the same size as the anal fin and is set immediately above it. The terminal lobe of the caudal fin has a notch in it and is as long as the rest of the fin. School sharks are dark bluish grey on their upper (dorsal) surfaces and white on their bellies (ventral surface). Juveniles have black markings on their fins. Mature sharks range from 135 to 175 cm (53 to 69 in) for males and 150 to 195 cm (59 to 77 in) for females. The school shark has a widespread distribution and is found mainly near the seabed around coasts in temperate waters, down to depths around 800 m (2,600 ft). It occurs in the Northeast Atlantic and Mediterranean Sea, where it is uncommon and the Southwest Atlantic where it occurs between Patagonia and southern Brazil. It also occurs around the coast of Namibia and South Africa. It is present in the Northeast Pacific where it occurs between British Columbia and Baja California, and in the Southeast Pacific off Chile and Peru. It also occurs round the southern coasts of Australia, including Tasmania, and New Zealand. The school shark is a migratory species. Animals tagged in the United Kingdom have been recovered in the Azores, the Canary Islands, and Iceland. Tagged individuals in Australia have travelled distances of 1,200 km (750 mi) along the coast and others have turned up in New Zealand.