Goblin shark

The Goblin shark is a species of shark known by the scientific name Mitsukurina owstoni. They are rare, deep sea sharks found in the Atlantic, Pacific, and Indian Oceans. This species in the Misukurinae family is the only known living fish, thought to be hundreds of years old. Goblin sharks have a mouth full of rotating teeth, like more common species of sharks, which are often lost and reproduced quickly. However, it is perhaps best known for its snout, which is similar to that of a swordfish, protrudes outward while the mouth is hidden and extends outwards to catch prey at short distances. Their diet consists of small crustaceans, cephalopods, and bony fish in the regions of which it lives. When deep-sea marine biologist have studied M. owstoni it appears to have a lethargic, passive lifestyle because it has not attacked many biologist. Goblin sharks have been caught by civilians and commercial fishers in Asia, Africa, and Oceania, who have turned in their specimen to local biologist to be studied. Some scientist spectate that the shark may be ovoviviparous (mother develops eggs inside her body until the eggs are ready to hatch), while others insist it is viviparous (live birth without eggs). Its reproductive behaviors are most likely similar to other species of sharks, where the shark embryo eats the other weak ones. Because goblin sharks are rare, they have yet to been studied fully for their mating habits and ecology.

Body Design


 Mitsukurina owstoni  has small dorsal, pectoral, pelvic and anal fin, while the caudal fin is extremely long and eel-like. Their skin is most often a pink-gray hue which darkens with age; young goblin sharks are usually white. The snout is very pointed similarly to a swordfish, protruding outwards and overhanging the mouth. Its mouth is like other sharks', because there are many rows of teeth that rotate. The mouth is designed to reach out and snap prey easily. The skin is made up of rough dermal denticles, also known as placoid scales which produces smooth and silent swimming through depths.

In addition to its fear-inducing face, the goblin shark is also very long, an average of 3 to 4 meters long for males, and 5-6 meters for females.The goblin shark's eyes do not contain a nictitating membrane, thus eyesight is limited. Many records of the iris show black with blue stripes. The shark's five pairs of gill slits are vary small in length. Four pairs are directly in front of the pectoral fins, with the fifth directly above them. Its fins are usually a bluish-gray color. Both the fins and eyes morph into a dull brown coloration after death.

Life Cycle


Because the goblin shark is so rare, little is known about its reproductive behaviors. Some speculate that its tendencies are similar to other predator sharks, which are viviporous, meaning live birth with gestation inside female, while some believe is is ovoviviparous, meaning growth outside of the female. The strongest shark embryo tends to eat the other undeveloped eggs during gestation. Very little is known about mating habits, growth, and death.

Ecology


Several  Mitsukurina owstoni  catches by locals have been reported in Japan, Taiwan, southern Africa, New Zealand, and Australia, hinting that its habitat might be in the Pacific Ocean waters. However, there have been reported sighting in the Gulf of Mexico spanning to Brazil, as well as off the coast of France and Portugal. Because of its lethargic, passive behavior to humans, it is possible that the goblin shark inhabit many waters. The depth range for this animal is 270–960 meters and the goblin shark probably lives within temperate regions.

From records of dissected stomach contents observed diet includes cephalopods (head-footed marine organisms such as octopi and squid), small bony fish, and unknown species of crab. Goblin sharks probably use their snout to detect prey in the water, then extend their mouth to capture. Their esophagus sucks up the food then digestion takes place in the body.

Media Spotlight
Mitsukurina owstoni was caught by fisherman Carl Moore in the Gulf of Mexico April 19, 2014. Moore believed that this shark was 5-6 meters long, though biologist John Carlson thinks it was around 4.5 meters. Moore began to measure the shark, but it began to thrash upon the deck of his ship. Therefore, he took a few photos scientists could use to examine the creature's physical appearance. Moore then proceeded to free the shark, which was still thrashing around, alive and well. Carlson quips that Moore made a monumental discovery which could help scientist help research and log key features and characteristics. Carlson recalls that goblin sharks, although rare, are mostly found off the coast of Japan. "They're not seen anywhere all that often, though the coast of Japan boasts the shark's share of recorded sightings." says CNN journalist Mark Morgenstein. More recent sightings will help marine biologist learn about their mostly unknown sizes and instincts.

In the eastern province of Sri Lanka, in a town known as Valaichchenai, fishermen caught a goblin shark claiming it was 7.5 meters, though biologist estimate Mitsukurina owstoni is anywhere from 3 to 6 meters. Locals took the shark ashore, then proceeded to take pictures with it. It is unknown if they killed the shark, or released it back into the water.

Japanese journalist Kasai Rinkai Suizokuen traveled with the staff of Tokyo Sea Life Park on January 25, 2007, where they managed to catch M. owstoni 1.3 meters long. While photographing and logging any information gathered, they brought the goblin shark back to the aquarium. The depth of where they caught the shark is estimated to be about 160 meters deep. The staff put the shark into a large tank with other exotic species, including Beryx splendens and Squalus japonicus. It appeared to be confused and distressed for a while, bumping into the glass sides and swimming in odd places. It eventually adapted to the aquarium and was swimming naturally.

Video
Video of displaying  Mitsukurina owstoni  in deep water. Fao8IIMMBKs XoKmCTlAnYM