Open-mouthed and propped up on their pectoral fins with mouth and gills held above the substrate, they rest facing into the current.Īlthough usually solitary, zebra sharks do form loose aggregations of 20 to 50 sharks in shallow coastal areas during the breeding season. Nocturnal sharks, they spend daylight hours lying on the ocean bottom, often in passes and channels through a reef crest where tidal flow brings in oxygen-bearing seawater. In areas where there is a suitable current they have been observed ‘surfing’, adjusting their fins to remain almost motionless in the water column. This shark species is slow-swimming, moving with a pronounced eel-like wiggle. The zebra-striped pup is 20 to 26 cm (7.9 to 10 in) when it emerges from the egg case and is immediately independent, able to swim and hunt on its own. Fine, hair-like fibers that cover both sides of the egg case anchor the case to the substrate where it will remain for about six and a half months (if not eaten by a predator). The female releases one to four large dark brown or purplish-black egg cases that are about 17 cm (6.7 in) long and 5 cm (2 in) in diameter. Zebra sharks reach maturity when the males are 1.5-1.8 m (5-6 ft) and the females 1.7 m (5.6 ft) in length. Their flattened teeth with three raised points (cusps) and short jaws work together to grip, crush, and pulverize shelled invertebrates. Their preferred prey is snails and bivalves but they also eat crabs, shrimps, and small bony fishes. These sharks are from 2-3.5 m (5.5 to 11.5 ft) in length with an average of 2.6 m (9 ft). Their body ridges start to form and their bars fade, becoming black dots or open dark circles on a yellow to cream or light gray background, the adult coloration. At this time they begin to develop their adult features. They change coloration when they are 50 to 70 cm (20 to 27 in) in length. Juveniles are dark brown or blackish with narrow pale yellow or white vertical bars and/or spots. The large pectoral fins are very rounded. There are two dorsal fins immediately adjacent to each other with the first much larger than the second. It has a deep terminal notch but the lower lobe is only slightly notched. The caudal fin is almost as long as the body. A ‘face’ is formed on the ventral side of the head by the blunt snout, prominent nares, a small transverse mouth, and short barbels at the front of the snout. Prominent longitudinal ridges run down their dorsal surface and on the flanks. Physical CharacteristicsĪdults have a cylindrical body with a broad head and small mouth. Juvenile zebra sharks inhabit deeper waters than adults seeking depths of 50 m (165 ft) to hide from predators. There is an unconfirmed report of a zebra shark living in fresh water in the Philippines. HabitatĪdult zebra sharks prefer inshore marine or brackish waters with depths from intertidal to 30 m (99 ft) where there are reefs and sandy, rubble, or coral bottoms. Indo-west Pacific: Red Sea and East Africa to New Caledonia, north to southern Japan, south to coast of western Australia, around tropical north and south to central coast of New South Wales. The Aquarium has zebra sharks on view in the Shark Lagoon and Tropical Reef exhibits. CLIMATE CHANGE: Not Applicable At the Aquarium
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