![]() ![]() Recently, there have been localized fisheries for whale sharks in the Philippines, India, and Taiwan. Most species in the order are not threatened by fisheries. The reproductive processes of the nurse shark are probably the best known (see species account following). Little is known about the reproductive processes of most orectolobiformes. Reproductive biologyīoth oviparous and viviparous species have been reported. Little information exists on creatures that are predatory towards fishes in this order, but carcharhinid sharks are known to prey on small orectolobiformes. The whale shark, the largest fish in the world, with a maximum length of 39 ft (12 m), feeds on plankton. Most of the orectolobiformes are small, sluggish sharks that feed on small invertebrates and fishes. Almost nothing is known about the behavior of most species. Most orectolobiformes are sluggish bottom-dwelling sharks that hide among the bottom rocks or coral heads during the day. The whale shark is the only pelagic species in the order. They often are bottom dwellers in rocky areas or coral reefs. With a few exceptions, most of the species of the order are found in the shallow waters of the continental shelves. The whale shark has worldwide distribution. The nurse shark ( Ginglymostoma cirratum) is found in both the Pacific and Atlantic Oceans. Only two species are found in other oceans. The Orectolobiformes are mainly an Indo-Pacific species. The Orectolobiformes are small to very large sharks with prominent nasoral grooves (grooves connecting the nostrils to the mouth), nasal barbels, two dorsal fins, an anal fin, and small terminal or subterminal mouths. The order Orectolobiformes comprises seven families: the Rhincodontidae ( whale shark), the Stegostomatidae (zebra shark), the Orectolobidae (the wobbegongs), the Ginglymostomatidae (the nurse sharks), the Parascyllidae (the collared carpet sharks), the Brachaeluridae (the blind sharks), and the Hemiscyllidae (the longtail carpet sharks). The Orectobiformes have a Jurassic record and show relationships to the Hybodontiformes, Squatiniformes, and Squaliformes, with such common characters as a flange on the teeth and nasal barbels. Zebra sharks can breathe without moving forward – they have the ability to pump water into their spiracles.The exact origin of this group is unclear. ![]() Their tendency to stay close to the ocean floor keeps Zebra sharks close to their common prey (mollusks) and allows the Zebra shark long periods of rest. Zebra sharks are also known as “carpet sharks” because of their bottom-dwelling behavior. A Zebra shark is not likely to harm humans in the wild. Even when hunting, the Zebra shark spends most of its time near the ocean floor and displays sluggish, easygoing behavior. They usually hunt at night.Īlthough sharks have a reputation as aggressive predators, zebra sharks tend to take it easy most of the day. Although their mouths are small, Zebra sharks have strong jaws that can crush mollusk shells. Their diet includes shelled mollusks, like clams, but Zebra sharks may also eat smaller fish such as herring. These sharks eat mostly from the ocean floor. As the Zebra shark matures, its pattern changes from stripes to spots. The Zebra shark is named for the stripes it displays while young.
0 Comments
Leave a Reply. |