The zebra shark is a large, distinctive shark that lives in shallow coral reef habitats in tropical waters where they can wriggle into narrow crevices and caves in search of food. Its appearance, which changes as the shark reaches maturity, has caused confusion among divers who often mistake it for the leopard shark. While the zebra sharks are born dark brown with yellowish stripes, as they reach adulthood, they shed their stripes for small black dots against a tan body, closely resembling the leopard species.
Zebra sharks are nocturnal foragers, hunting for small fish, snails, sea urchins, crabs and other small invertebrates that hide out in crevices. Even though they may not look as ferocious as their toothy relatives, the zebra shark’s body is perfectly adapted for snatching up prey. Barbels, or whisker-like organs at the front of their snouts, help them seek out prey, while a flexible body allows them to wriggle in tight spaces where small fishes are often hiding. They also have small mouths and strong gill muscles to easily suck up prey in one gulp. During daylight, the zebra shark prefers to rest on the ocean floor facing the current so they can efficiently pump water over their gills and breathe while remaining still. If the current is strong enough, this slow-moving shark species has been observed “surfing,” adjusting its fins to remain motionless in open water.
During reproduction, male zebra sharks transfer sperm to the female using claspers, or modifications of the pelvic fins, and the female can lay up to four eggs at a time. The egg cases are covered in fine fibers that keep them anchored to the sea floor for about six and a half months while developing. A zebra shark pup may be less than a foot long at birth, but an adult can grow to be almost 12 feet and have a tail that reaches half its full body length. Adult zebra sharks are non-aggressive, and have few predators other than larger shark species that may be lucky enough to catch one in its jaws.
As with other sharks, the largest threat to zebra sharks is humans. The zebra shark is taken by a wide range of inshore fisheries and prized for its meat, which may be sold fresh or salt-dried in markets throughout Indonesia, Thailand, Malaysia, Philippines, and elsewhere. Its liver is also processed for vitamins and its fins are chopped off for use in shark fin soup that remains a traditional Chinese delicacy. Although the practice of shark finning is illegal in U.S. waters, fins can still be bought and sold from unsustainable foreign fisheries, which are lacking or have ineffective shark finning bans. The combination of these practices is driving down zebra shark populations in most of their range, and they are considered endangered by the IUCN Red List. However, in Australia, the species is considered of Least Concern because it has a wide distribution and is not heavily fished.
1. Zebra sharks are usually found over sand near coral and rocky reefs as deep as 203 feet (62 m).
2. Zebra sharks reach a maximum length of about 8 feet (2.5 m) and live over 28 years in aquaria.1
3. Zebra sharks are often confused with leopard sharks because they are born dark brown with white bars across their bodies, but become light yellow with small dark spots as they mature.
4. Zebra sharks mostly live in marine waters, but have been spotted in brackish and freshwater habitats.
5. Zebra sharks can squeeze into narrow crevices to search for food, but they’re also very lethargic and spend most of their time resting on the seafloor.2
Oceana joined forces with Sailors for the Sea, an ocean conservation organization dedicated to educating and engaging the world’s boating community. Sailors for the Sea developed the KELP (Kids Environmental Lesson Plans) program to create the next generation of ocean stewards. Click here or below to download hands-on marine science activities for kids.