Nervous shark

Nervous shark ( Carcharhinus cautus )

The Nervous shark ( Carcharhinus cautus ) is a species of the genus Carcharhinus within the requiem sharks ( Carcharhinidae ). The species is widespread in the waters around Australia, Papua New Guinea and the Solomon Islands. Its name derives from the timidity of the shark against swimmers and divers.

Appearance and characteristics

The Nervous shark is a medium sized shark with a maximum body length of about 150 cm and average lengths between 100 and 130 centimeters. He has a gray - brown to bronze-colored body paint, a clear white band on the flanks and a whitish belly region without patterning. The dorsal and pectoral fins, and the caudal fin has a black border, which expires at the tail fin and the pectoral fins to a black fin tip.

He has an anal fin and two dorsal fins. The first dorsal fin is tall and falcate and is slightly ahead of or relating to the free ends of the pectoral fins. The second dorsal fin is relatively high with a height of 3-4 % of the body length of the animal. Like all species of the animals have five gill slits and have no spray hole.

The Nervous shark resembles in habit the other species of the genus Carcharhinus, particularly with the blacktip reef shark ( Carcharhinus melanopterus likelihood of confusion ). However, this also has the anal fin and the dorsal fin eye-catching black fin tips.

Way of life

The Nervous shark is a Flachwasserart and feeds primarily on various predatory fish of the shore zone, also he chases a lesser extent, crustaceans and squid. The sharks are viviparous and form a yolk sac placenta ( placental viviparous ). The females get after a gestation period 8-9 months in a litter of between one and five juveniles with a length of about 35 to 40 cm.

Dissemination

The Nervous shark is widespread in the eastern Indian Ocean and the South Pacific in tropical waters in the area between latitudes 5 ° S and 30 ° S to Australia (Queensland, Western Australia ), Papua New Guinea and the Solomon Islands. He is mainly found in shallow waters above the continental shelf, as well as possibly also in deeper waters.

Relevance to humans

The Nervous shark is generally regarded as harmless, usually he avoids encounters with swimmers and divers. He is caught and eaten in small numbers of individuals, an estimate of the total catch numbers or influence over the population does not exist.