Adult zebra sharks are distinctive in appearance, with five longitudinal ridges on a cylindrical body, a low caudal fin comprising nearly half the total length, and usually a pattern of dark spots on a pale background. It is found throughout the tropical Indo-Pacific, frequenting coral reefs and sandy flats to a depth of 62 m (203 ft). The zebra shark ( Stegostoma tigrinum) is a species of carpet shark and the sole member of the family Stegostomatidae. Squalus pantherinus Kuhl & van Hasselt, 1852 Their preferred shallow water habitat is also easily destroyed by human activities such as coastal development and bottom trawling-a destructive fishing method which involves dragging large, weighted nets across the seafloor.īecause these sharks have a slow reproductive rate, it takes even longer for the species to recover from these threats.Ĭonservation efforts-including tagging to better understand individuals’ movements, and repopulation attempts through releasing eggs laid in captivity-are underway around the world to help protect this endangered species.Scyllia quinquecornuatum van Hasselt, 1823 ( Learn about the perils of overfishing.) Populations around the world are decreasing due to overfishing, bycatch, and the shark fin trade. Although they do sometimes fall prey to larger predatory sharks, their main threat is from humans. Zebra sharks are endangered, according to the International Union for Conservation of Nature. In zebra sharks, these virgin births have been documented both in females that had never mated and those that had previously reproduced with a male. While over 80 vertebrate species are known to reproduce using parthenogenesis, it’s rare in complex vertebrates such as sharks. In 2011, scientists were excited to document parthenogenesis in zebra sharks-a phenomenon that’s essentially a virgin birth, in which unfertilized eggs develop into genetically unique embryos without any male involvement. ( Learn how some animals have ‘virgin births.’) Pups are born fully independent and can swim and hunt on their own. Pups develop inside the casing for around six and a half months before emerging as 10-inch baby sharks. After mating, a female will use special fibers to attach between one and four egg casings securely to the seafloor. Zebra sharks are oviparous, which means they lay eggs. They can also crunch through tough shells with their strong, flat teeth. After using their whisker-like barbels to detect prey in the dark, they use their small mouths and powerful gill muscles to suck their meal from its shell. Their flexible bodies allow them to squeeze into tight crevices to seek out small invertebrates to eat. They are well adapted for finding and eating this type of prey. DietĪ zebra shark’s diet is mainly made up of mollusks and crustaceans, though they are also known to eat small fish. Unlike some other species of shark, zebra sharks don’t have to keep swimming to breathe. They hunt at night and rest on the bottom during the day while pumping water over their gills. This nocturnal species can be found in shallow coral reefs in the Indo-Pacific, often resting on the sandy seabed. Because their stripes mimic those of a venomous sea snake, other species keep away in case the pattern indicates danger. In the ocean, a zebra-striped pattern is an important defense mechanism for the small, vulnerable pups. Adults look so different from juveniles that until 1823, scientists believed they were two separate species. These stripes fade over time and turn into the leopard-like spots they keep into adulthood. Juveniles are born with dark-brown-and-white stripes resembling the patterns of a zebra. They have rounded, sandy-colored bodies with five ridges, small mouths, whisker-like organs called barbels in front of their snout, and powerful tails that can be nearly as long as the rest of their bodies.Īdults usually grow up to nine feet long-around the same length as a Bengal tiger-but have been reported to reach 12 feet. Zebra sharks don’t look like the ferocious hunters most people expect of a shark.
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