Isistius+brasiliensis



Latitude: Temperature- 30-49 c. Salinity- 10-30 ppt Latitude/Longitude: between 30- 90 Pressure: 10 atmospheres Survival Trends: A dark patch on the ventral surface of the cookiecutter shark resembles a smaller fish when viewed from below and is thought to lure larger fish and marine mammals that may be swimming beneath it. When this sneaky predator attacks its prey, it grabs hold of the flesh with its lips and bites using its small, sharp upper teeth to grip the prey while it cuts the flesh with the large, serrated lower teeth. The cookiecutter shark then spins its body to remove a "cookie-shaped" plug of flesh which it swallows before releasing its prey. Appearance: The cookiecutter has a cylindrical body that reaches up to 50 cm in length. It has a conical snout and 2 low spineless dorsal fins positioned at the posterior end of the body. It is dark brown to black on its dorsal side, lighter ventrally, and possesses a dark collar around the gill region. The entire ventral (lower) surface, with the exception of its dark collar, is covered in a dense network of tiny photophores which emit a greenish glow. This glow is reported to last as long as three hours after the shark's death. Reproduction:** Reproduction of the cookie-cutter shark is accomplished through internal fertilization. The male has instead two 'claspers' (pterygopodes), located on his underside in the rear. Fertilization is accomplished by his insertion of one of his claspers into the female's cloaca. Like other small sharks, this shark is oviparous, and the female coats her eggs in a horny casing before attaching them to rocks and seaweed. Hatching can take place after 12 to 22 months. When the young emerge, they are fully developed and capable of hunting for themselves. Males mature at approximately 14 inches and grow to a size of 16 inches, while females mature at 16 inches and reach up to 20 inches (Stoakely 1997). There are 6-12 live young born per litter. Oceanic islands provide nursery habitats for these species. //Dentition// It preys on an assortment of deepwater organisms, including crustaceans, squid, large bony fishes, whales, and even large sharks. Cookie-cutter sharks have been known to bite into submarines, which they apparently mistake for prey. by
 * Animal Classification:** Isistius Brasiliensis
 * Family:** Dalatiidae
 * Class:** Condrichthysefile
 * Order:** Squaliformes
 * Endangered Species Act:** Least concered, assesed in 2003. The cookie cutter shark is not on the endangered species list because it is too small to be regularly taken by fisheries and other than being occasionally caught there are no significant threats on this species.
 * Habitat:** Lives in warm, deep waters of equatorial ofceans, primarily in coastal waters near islands. They inhabit deep waters below 1,000 m. They have been found in depthys up to 3,500 m.
 * Location of ecosystem:** Equatoria oceans, benthic, various locations among the south pacific
 * Physical Habitat features:** Tide- 1.7 ft. Current- the current flows north along the coast of south America
 * Geological Process:** It is typical that earthquakes, volcanos, and sea floor spreading occur
 * Migration Patterns: Many deep-sea creatures undergo a nightly 'vertical migration', following their prey toward the surface at night and returning to deeper zones before dawn.
 * Animal anatomy and physiology: The cookiecutter shark has a small cigar-shaped body with a short conical snout and unique suctorial lips. The eyes are located toward the front of the head, but far enough back that the shark lacks much of a binocular field of vision. There are two close-set spineless dorsal fins of equal size positioned toward the rear of the body. The pelvic fins are larger in size than the dorsal fins; the pectoral fins are subquadrate in shape. The caudal fin is large with a long ventral lobe. The anal fin is absent on this species. **
 * Economic importance of species (tourism, fishery, medical):** They have a potential negative impact on fisheries, as they prey on commercially important fish, but damage is slight. The attacks on submarines are considered at most a nuisance. Because of its small size, and deep water habitat, this species is of little or no danger to swimmers and divers.
 * Threats and reasons for endangerment:** For now their population remains stable, but increased pressure from fishing and a lack of law enforcement could eventually catch up with this shark. Sharks play a crucial role in reef and ocean ecosystems. They prey on weak and diseased animals. Human choices and human interference cause their numbers to decline. Some countries manage their coastal waters to protect sharks. But others have lax fishing laws, or too few resources to enforce laws that exist. In these places, shark populations suffer.
 * Conservation efforts:** FAO (Food and Agriculture Organization of the United Nations) member countries have been working for about a decade to create a plan of action for the conservation and management of sharks throughout the world. Many participating countries have been successful in their efforts. However, the vast size of the ocean and the lack of law enforcement in many areas maintain poor conservation and management of sharks globally.
 * Solutions:** The cookiecutter shark is listed as "Least Concern" with the World Conservation Union (IUCN). The IUCN is a global union of states, governmental agencies, and non-governmental organizations in a partnership that assesses the conservation status of species. The only thing we can stop doing is catching the fish at night when they come closer to the surface of the water because that is the only time that anything detrimental to their species is done.
 * Did you know? :** For up to three hours after its death, the cookie cutter shark will emit a glow from its mouth. Cookie cutter sharks are classified as parasites. Parasites hurt their prey, but don’t kill them—just like the cookie cutter. This shark has never been known to attack a person—probably because they live in deep areas of the ocean where people can not venture.

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