similan islands diving – leopard sharks

As part of our ongoing series of Similan Island Marine Life, Wicked Diving presents:

Leopard Sharks


Leopard Sharks are the common Name in Asia for Stegostoma fasciatum, which is very common on the Similan and Surin Islands. In The Americas it is the name for a very different shark – Triakis semifasciatum.


Description & Behavior
The zebra shark, Stegostoma fasicatum (Hermann, 1783), is also known as a leopard shark in SE Asia. The zebra shark has a cylindrical body with prominent ridges on the sides and 5 gill slits (slits 4 and 5 overlap). The tail lacks a ventral lobe and it is as long as the body. This shark has a broad head, small barbels, and a transverse mouth located in front of the eyes. Its spiracles are as large as its eyes. The spineless dorsal fins are back to back. The anterior dorsal fin is much larger than the posterior dorsal fin. The first dorsal fin appears above the bases of pelvic fins, the second dorsal fin is about as large as the anal fin. The body is gray-brown with dark spots in adults. Juveniles are darker with light stripes and spots. Maximum size is about 3.5 m, average size between 2.5-3 m.

World Range & Habitat
Indo-Western Pacific: South Africa to Red Sea and Pakistan, India, Sri Lanka, Bangladesh, Indonesia, Thailand, Vietnam, Philippines, China, Japan, Australia, New Caledonia, Palau. Lives over the continental and insular shelves. Very common around coral reefs, often on sandy bottoms, but little is known about its biology. It is known that this species props up its pectorals in the sand and faces the current with open mouth. Such behavior and its inactivity during the day points towards a more sluggish life style and indicates that it is probably a nocturnal hunter. Recorded to have entered freshwater.

Description & Behavior
The zebra shark, Stegostoma fasicatum (Hermann, 1783), is also known as a leopard shark in SE Asia. The zebra shark has a cylindrical body with prominent ridges on the sides and 5 gill slits (slits 4 and 5 overlap). The tail lacks a ventral lobe and it is as long as the body. This shark has a broad head, small barbels, and a transverse mouth located in front of the eyes. Its spiracles are as large as its eyes. The spineless dorsal fins are back to back. The anterior dorsal fin is much larger than the posterior dorsal fin. The first dorsal fin appears above the bases of pelvic fins, the second dorsal fin is about as large as the anal fin. The body is gray-brown with dark spots in adults. Juveniles are darker with light stripes and spots. Maximum size is about 3.5 m, average size between 2.5-3 m.

World Range & Habitat
Indo-Western Pacific: South Africa to Red Sea and Pakistan, India, Sri Lanka, Bangladesh, Indonesia, Thailand, Vietnam, Philippines, China, Japan, Australia, New Caledonia, Palau. Lives over the continental and insular shelves. Very common around coral reefs, often on sandy bottoms, but little is known about its biology. It is known that this species props up its pectorals in the sand and faces the current with open mouth. Such behavior and its inactivity during the day points towards a more sluggish life style and indicates that it is probably a nocturnal hunter. Recorded to have entered freshwater.

Endangered Species….

Read the UN report on endangered species

Feeding Behavior (Ecology)
Feeds primarily on snails and other molluscs, but also on crabs, shrimps, and small bony fishes.

Life History

Egg laying (oviparous). Egg cases are large (17 cm long, 8 cm wide, 5 cm thick). Unknown if the female lays more than one egg at a time, but it is most likely. Hatch size between 20-36 cm. Males reach sexual maturity between about 1.5-1.8 m, females around 1.7 m.

Comments
Harmless. This species is regularly taken in inshore fisheries and a decline is likely (no data) if not in progress. Utilized fresh and dried-salted for human consumption and also for fishmeal; livers processed for vitamins; fins cut off for the oriental sharkfin trade.

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