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Archive for March 2010

Above the Goblin shark

1. The first goblin shark was found in 1897 and in 1909. people believe that the goblin is a related to a extinct sharks called Scapanorhynchus and Anomotodon. The shark got is name by it goblin like nose and face. And the species was named by Jordan in honor of avid wildlife collector Alan Owston, who acquired the first specimen from a Japanese fisherman.

2. The Goblin shark is a deep-water shark usually found near the sea bottom, at depths of around 250 m. The deepest specimen ever caught was found at 1,300 m. There are only about 45 known specimens of Mitsukurina owstoni. Most goblin sharks that have been caught  from Japan where it was first discovered, specifically in an area between Tosa Bay and Boso Peninsula. The species’ Pacific range is rather large. M. owstoni specimens have been found in the waters off South Africa, from various sites throughout the western Pacific Ocean. Goblin sharks have also been found off the coasts of Australia and New Zealand. In the Atlantic Ocean, they have been found in the western Atlantic off French Guiana, in the eastern Atlantic in the Bay of Biscay and off Madeira and Portugal. On the other side of the Atlantic, goblin sharks have been found in the Gulf of Mexico.

3. Goblin sharks can grow to 11 feet (3.3 m) long and weigh 350 lb (159 kg). They have the typical shark’s semi-fusiform body. Unlike most sharks, M. owstoni’s fins are not pointed and instead are low and rounded, with the anal and pelvic fins significantly larger than the dorsal fins. Their heterocercal tails are similar to the thresher shark’s, with the upper lobe significantly longer proportionately than other sharks’. In addition, the goblin shark’s tail lacks a ventral lobe. The pink coloration, unique among sharks, is due to blood vessels underneath a semi-transparent skin, thereby causing the coloring. The fins have a bluish appearance. Goblin sharks lack a nictitating membrane. They have no precaudal pit and no keels. The front teeth are long and smooth-edged, while the rear teeth are adapted for crushing.

4. Goblin sharks hunt by sensing the presence of prey with electro-sensitive like most shark, due to the absence of light in the deep waters where it swims. Once a shark finds its prey, it suddenly protrudes its jaws, while using a tongue-like muscle to suck the victim into its sharp front teeth. Some prey they have been known to feed on include deep-sea rockfish, cephalopods and crustaceans.

5. Next to nothing is known of the goblin shark’s reproductive habits. Even though a pregnant goblin shark has never been caught or found, as members of the order Lamniformes, they are assumed to be ovoviviparous; their eggs mature and hatch inside the mother’s body and the shark gives birth to live young.

All of this info is from http://en.wikipedia.org/wiki/Goblin_shark

Above the Frilled Shark

1. The frilled shark is a dark brown or grey eel color and the six gill slits make it a wired looking shark from most sharks. It’s dorsal fin is small, anal fin large and the tail fin is highly asymmetric and the dorsal part almost unnoticeable. Its teeth are small, tricuspid and very sharp. Mature males can grow to be 1 meter (3.3 ft) – 1.1 meters (3.6 ft) in length and females can grow to be 1.4 meters (4.6 ft) – 1.5 meters (4.9 ft).  It has been recorded at up to 2 meters (6.6 ft) in length

2. The frilled shark is a species of deep-sea shark in the shark family this shark is known as a “living fossil”. It was long thought to be the only member of its family until in 2009. The frilled shark was thought to be extinct itself until it was discovered alive in Japanese waters in the 19th century. On January 21, 2007 a specimen was found alive off the coast of Japan near the Awashima Marine Park in Shizuoka, southwest of Tokyo. The shark was captured but was not adapted to live in the warm, shallow water that it was moved to. The specimen died soon after capture. Is worldwide, but they are very rarely found in shallow water. They have been reported in all oceans but are mainly found near Norway, South Africa, New Zealand, and Chile. The sharks are usually found at depths of between 50 meters (160 ft) and 1,500 meters (4,900 ft). They typically eat squid, other sharks, and deep water bony fish. The frilled shark is sometimes referred to as a living fossil partly because the species has changed little since pre-historic times.

3. The reproduction is not well-understood, but like many other sharks they bear live young with litter sizes of 2 to 12 pups, although the average is six pups. Frilled sharks have the longest gestation period currently known among animals since it remains pregnant for 3.5 years before giving birth.

4. Frilled sharks appear regularly in the catches from bottom trawling and when caught are used as food or for fishmeal. On January 21, 2007, staff at Awashima Marine Park in Shizuoka, southwest of Tokyo, were alerted by fishermen to a ‘strange eel-like fish with needle-like teeth’. The fish was identified as a pregnant female 1.6 m frilled shark and was captured by park staff who were concerned that the shark appeared to be unhealthy. They took it out of the water and put it into a salt water tank where they filmed it and took pictures of it. The shark died a few hours after capture. This rare surface appearance of a frilled shark has been attributed to the animal being unable to live in the warmer temperature water. The frilled shark living in the colder deep ocean water.

All of this info is from http://en.wikipedia.org/wiki/Frilled_shark

Above cretoxyrhina

1. Cretoxyrhina is all so known as the Ginsu Shark. The Ginsu shark is the most well understood fossil sharks to date. A few preserved part have revealed a great deal of insight about the physical features and lifestyle of this ancient shark.

2. Cretoxyrhina was a large shark that lived during the Cretaceous period, about 100 to 82 million years ago.

3. The fossil teeth of Cretoxyrhina are up to 7 cm long, curved and smooth-edged, with a thick enamel coating.

4. Cretoxyrhina grew up to 7.5 meters (25 ft) long and was larger than the great white shark.

5.The Ginsu shark was the largest shark in its time and was among the top predators of the seas. Fossil records revealed that it preyed upon a number of marine animals such as, Mosasaurs, Plesiosaurs, Xiphactinus, and protostegid turtles.

6. The specimen from Niobrara Chalk of western Kansas supports the idea that the body of the Ginsu shark looks like the great white shark. The caudal fin morphology of the Ginsu shark was an active shark and capable of fast swimming so the believe.

7. The Ginsu shark lived in Cenomanian–Campanian seas worldwide and including in the Western Interior Seaway of North America.

All of this info is from http://en.wikipedia.org/wiki/Ginsu_Shark

Well a few days ago my dad got me a baby megalodon tooth. My megalodon lived 2 to 5 millions years ago. And is 3 and a half centimeters.

Here are some photos

Above the basking shark

1. This shark is called the basking shark because it is most often observed when feeding at the surface and appears to be basking in the warmer water there.

2. The basking shark is found worldwide in warm waters and cold waters. But it prefers 8 to 14 °C (46 to 57 °F) temperatures, but recently has been confirmed to cross the much-warmer waters at the equator. It is often seen close to land, including bays with narrow openings. The shark follows plankton and therefore often visible at the surface. The basking shark is found from the surface down to at least 910 meters (2,990 ft).

3. The largest accurately measured was trapped in a herring net in the Bay of Fundy, Canada in 1851. Its total length was 12.27 metres (40.3 ft) and it weighed an estimated 19 short tons (17 t). Normally the basking shark reaches a length of between 6 metres (20 ft) and a little over 8 metres (26 ft). Some specimens surpass 9–10 metres (30–33 ft) but after years of large-scale fishing, specimens of this size have become rare.

4. Studies in 2003 proved that basking sharks do not hibernate, showing that they are active year-round. In winter, basking sharks move to depths of up to 900 metres (3,000 ft) to feed on deep water plankton.

5. Tagging confirms that basking sharks move thousands of kilometres during the winter, seeking plankton. It also found that basking sharks shed and renew their gill in an ongoing process, rather than over a short period. A 2009 study tagged 25 sharks and at least some migrate south for the winter. Remaining at depths between 200 metres (660 ft) and 1,000 metres (3,300 ft) for many weeks, the tagged sharks crossed the equator to reach Brazil. One individual spent a month near the mouth of the Amazon River. It is unknown why they undertake this journey. Some suspects it may to breed. And do not approaching boats (unlike great white sharks). They are harmless to humans if left alone and are not attracted to chum.

6. Basking sharks are social animals and usually in small numbers (3 or 4) but reportedly up to 100 individuals. Their social behavior is thought to follow visual cues. Although the basking shark’s eyes are small, they are fully developed. They may visually inspect boats. Females are thought to seek shallow water to give birth. These sharks have few predators but orcas and tiger sharks feed on them. Although it is unlikely that they are able to cut through the shark’s thick skin.

7. The basking shark feeds on plankton, small fish. They feed at or close to the surface with their mouths wide open. It relies only on the water that it pushes through its gills by swimming so it breath and feed at the same time.

8. Basking sharks developing embryos first rely on a yolk sac. Their seemingly useless teeth may play a role before birth in helping them feed on the mother’s unfertilized ova (a behaviour known as oophagy). Gestation is thought to span over a year (perhaps 2 or 3 years), with a small though unknown number of young born fully developed at  (4 ft to 6 ft). Mating is thought to occur in early summer and birthing in late summer, following the female’s movement into shallow waters. The age of maturity is not known but is thought to be between the ages of 6 and 13 and at a length of 4.6–6 metres (15–20 ft). Breeding frequency is also unknown, but is thought to be 2 to 4 years.

All of this info is from http://en.wikipedia.org/wiki/Basking_shark

Above the spiny dogfish shark

1. The spiny dogfish has dorsal spines, no anal fin, and white spots along its back. These are used defensively but if captured, the shark can arch its back to pierce its captor. Glands at the base of the spines secrete a mild poison.

2. Males mature at around 11 years of age, growing to 80–100 cm (2.6–3.3 ft) in length and females mature in 18–21 years and are a bit larger than males, reaching 98.5–159 cm (3.23–5.22 ft).

3. Both sexes are greyish brown color.

4. Mating takes place in the winter months with gestation lasting 22–24 months. Litters range between 2 and 11 but average 6 or 7 pups.

5. It is found mostly in shallow waters and further offshore in most parts of the world, especially in temperate waters.

In blue this is where it lives

All of this info is from http://en.wikipedia.org/wiki/Spiny_dogfish_shark

Above the dwarf lanternshark

1. At present time the dwarf lanternshark has only been reported from a small area of the Caribbean Sea and off the coasts of Colombia and Venezuela, occurring between Barranquilla and Santa Martaand near the Guajira Peninsula and between the Los Testigos Islands and Grenada. This shark can live at depths of 283–439 m (928–1,440 ft).

2. The dwarf lanternshark has a long wide, flattened head. The eyes are large. The nares are large and preceded by poorly developed flaps of skin. There are 25–32 tooth rows in the upper jaw and 30–34 tooth rows in the lower jaw. The five pairs of gill slits are small. The skin is densely covered by thin, needle-like dermal denticles in a random pattern, except for the lips and the tips of the fins. This shark is dark brown with a striking pattern of black markings on its ventral surface and broken fine black line along the middle of its back, a black band on the end of its caudal fin and a dark blotch on its lower caudal fin lobe. The largest known individual is 21.2 cm (8.3 in) long.

3. Perhaps the smallest living shark species, male dwarf lanternsharks mature at a length of 16–17.5 cm (6.3–6.9) and females from a length of 15.5 cm (6.1) with 19–20 cm (7.5–7.9) long pregnant individuals known. This species is ovoviviparous, with the developing fetuses being sustained by a yolk sac until birth. Females bear litters of 2–3 young, each measuring 5.5–6.0 cm (2.2–2.4 in) long.

All of this info is from http://en.wikipedia.org/wiki/Dwarf_lanternshark