The grey bamboo shark (Chiloscyllium griseum) is a species of carpet shark. This bottom-dwelling inhabitant of tropical waters is distinguished by its subtle coloration and nocturnal habits. Its relatively smaller size and docile nature make it an intriguing subject for study and public interest.
Identifying the Grey Bamboo Shark
The grey bamboo shark reaches an average length of 61 to 77 centimeters (24 to 30 inches), with males maturing between 45 to 55 cm. It has a slender, cylindrical body that is generally grey to brownish, often with a lighter, off-white underside. While adults may lack distinct patterns, juveniles exhibit approximately twelve transverse dark saddle bands across their bodies, which fade as they mature.
This shark’s snout is short and stout, featuring subterminal nostrils and small sensory barbels. Its mouth is positioned closer to its eyes than to the tip of its snout. The first and second dorsal fins are rounded and roughly equal in size, though slightly smaller than the pelvic fins.
Habitat and Diet
The grey bamboo shark inhabits the Indo-West Pacific Ocean, from the Arabian Sea to regions including India, Pakistan, Thailand, Malaysia, China, Japan, Indonesia, the Philippines, and Papua New Guinea. These sharks prefer shallow coastal waters, found at depths ranging from 5 to 100 meters (16 to 328 feet). They are commonly observed on sandy or muddy bottoms, within coral lagoons, and near rocky shores.
This species is a nocturnal feeder. Its diet primarily consists of small invertebrates such as crabs, shrimp, worms, and mollusks, along with small fish. They are sluggish bottom dwellers, often hovering on the seabed while foraging for prey.
Reproduction and Conservation
Grey bamboo sharks are oviparous. The mature female deposits small, oval egg cases, often called “mermaid’s purses,” directly onto the ocean floor, typically in pairs. The developing embryos within these cases rely entirely on the yolk for nourishment. Mating involves the male biting and holding onto the female’s pectoral fin.
The International Union for Conservation of Nature (IUCN) lists the grey bamboo shark as “Near Threatened.” This classification reflects concerns about its population due to various threats. The species is regularly caught in inshore fisheries, particularly off the coasts of Pakistan, India, and Thailand, where it is utilized for human consumption. Habitat degradation, bycatch from fishing operations, and overfishing contribute to its vulnerability, with no specific conservation actions currently in place for its protection.
Grey Bamboo Sharks in Aquariums
Grey bamboo sharks are found in both public and private aquariums. Their relatively smaller size and hardy nature contribute to their suitability for aquarium environments. While they can adapt to captive settings, maintaining them requires a significant commitment.
For proper care, a thick, fine sandy bottom is recommended in their tank. Water parameters must be carefully maintained, with preferred temperatures between 23-27°C (73-80°F), salinity between 1.023-1.026 specific gravity, and a pH range of 8.1-8.4. Their diet in captivity typically mirrors their natural diet, consisting of small fish, shrimp, and other invertebrates.