Thursday, January 24, 2008

Great White Shark

The great white shark, Carcharodon carcharias, also known as white pointer, white shark, or white death, is an exceptionally large lamniform shark found in coastal surface waters in all major oceans. Reaching lengths of about 6 m (20 ft) and weighing up to 2,250 kg (5,000 lb), the great white shark is the world's largest known predatory fish. It is the only surviving species

Great Hammerhead Shark

The bizarre shape of the head is thought to make the shark more sensitive to electrical signals, which they use to detect hidden prey.
Females average 3.65m and males 2.85m, but the largest specimen recorded was 6.10m.
Physical Description
Great hammerheads are a dark olive colour with a pale underside. They have a hammer-shaped head, with eyes positioned at the end of each extension. Hammerheads have triangular, serrated teeth. The dorsal fin (on the back) is very large and pointed.
Great hammerheads inhabit shallow reefs and are found at moderate depths offshore in all tropical waters worldwide. They can sometimes be found in water less than 1m deep.
Great hammerheads are solitary, unlike scalloped hammerheads, and feed on other small sharks, rays (including sting rays), squid and bony fish. They are considered to be dangerous and attacks on humans have been documented.
Females give birth to 20-40 live pups which are about 70cm long at birth.
Conservation status
Great hammerheads are not considered to be endangered although they are hunted for sport and for their skin, which is used as leather.

Gray Reef Shark

The grey reef shark, Carcharhinus amblyrhynchos, is one of the most common sharks in Indo-Pacific waters, from the Red Sea to Easter Island. It is found at depths down to about 250 m in lagoons and close to islands and coral reefs.
As its name suggests, the shark is grey overall, with a white underside. The tips of most fins, except the first dorsal fin, are darker, and the trailing edge of the caudal fin has a prominent black margin. Some individuals have a white pattern on the leading edge of the dorsal fin. It has been recorded at up to 2.55 m. The blacktip reef shark looks similar, and is also common, but it is distinguished by a black tip on the first dorsal fin.

Goblin Shark

The goblin shark, Mitsukurina owstoni, is a deep-sea shark, the sole living species in the family Mitsukurinidae.[2] The most distinctive characteristic of the goblin shark is the unorthodox shape of its head. It has a long, trowel-shaped, beak-like rostrum or snout, much longer than other sharks' snouts. Some other distinguishing characteristics of the shark are the color of its body, which is mostly pink, and its long, protrusible jaws.[2] When the jaws are retracted, the shark resembles a pink grey nurse shark (Carcharias taurus) with an unusually long nose.
Mitsukurina owstoni is found in the deep ocean, far below where the sun's light can reach at depths greater than 200 meters. They can be found throughout the world, from Australia in the Pacific Ocean[3] to the Gulf of Mexico in the Atlantic Ocean.[4] They are best known from the waters around Japan, where the species was first discovered by modern science.[5]
Goblin sharks feed on a variety of organisms that live in the deep waters they call their home. Among some of their known meals are deep-sea squid, crabs and deep-sea fishes. Very little is known about the species' life history and reproductive habits, as encounters with them have been relatively rare. As seemingly rare as they are however, there seems to be no real threat to their populations and so they are not

Ganges Shark

The Ganges shark, Glyphis gangeticus, is a rare species of fresh water shark that dwells in the Ganges River. It should not be confused with the Bull shark, which also inhabits the Ganges River and is sometimes referred to as the Ganges shark.

Frilled Shark
The frilled shark, Chlamydoselachus anguineus, is a primitive shark species, of the family Chlamydoselachidae in the order Hexanchiformes. The Southern African frilled shark is a proposed new species from the Southern African range. These two species are very different from the other hexanchiform sharks, and it has recently been proposed that the two frilled sharks should be given their own order: Chlamydoselachiformes. Additional extinct types are known from fossil teeth; thought to be extinct itself, it was only discovered in Japanese waters in the 19th century.[2] 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, being in poor health, died

Cookie Cutter Shark
The Cookie-cutter Shark is named after the cookie-shaped wounds that it leaves on the bodies of larger animals (see Related links, below).
This species has a small cigar-shaped body (up to about 50 cm in length), a conical snout and two low, spineless dorsal fins positioned posteriorly on the body. It is dark brown dorsally, lighter below, and has a distinct dark collar around the gill region (visible in the middle image). The entire ventral surface, with the exception of the dark collar, is covered in a dense network of tiny photophores, which in life produce an even greenish glow. The genus name Isistius is derived from Isis, the Egyptian goddess of light.
This species has small, erect teeth in the upper jaw and large triangular teeth in the lower jaw. The Cookie-cutter Shark attaches itself to its prey with its suctorial lips, and then spins to cut out a cookie-shaped plug of flesh from the larger animal.
A recent theory (Widder, 1998) suggests that the feeding behaviour of the Cookie-cutter Shark may be even stranger than originally thought. It is counterilluminated, a dark colour above and lighter below (due to the light organs).
The dark collar is not illuminated, so would be silhouetted against the light from above. The theory suggests that this dark area would look like a small fish from below, and the Cookie-cutter Shark would wait for a larger predator to attack the "small fish". As the predator is about to attack, the Cookie-cutter Shark would turn and attack the attacker. The forward motion of the larger animal may even assist the Cookie-cutter Shark in removing the plug of flesh.
In addition to plugs of flesh from larger animals, the Cookie-cutter Shark is also known to eat squid. There are even reports of this species leaving crater-marks on the sonar domes of submarines.
Cookie-cutter Sharks are recorded from scattered localities around the world. In Australia they have been recorded from Queensland, New South Wales, Tasmania and Western Australia. They vertically migrate, being found in deep water, probably below 1000 m during the day, and migrating into surface waters at night.

Cat Shark

Cat Shark :
Size: Typically, 60cm to 70cm - max recorded 4m
Weight: Unknown
Food Sources: Invertebrates and smaller fish
Habitat: Shallow reef and rocky bottom floors
Locations: Warmer waters worldwide
Interesting Facts: Has cat-like eyes and two small dorsal fins set far back

Carpet Shark

The order Orectolobiformes, also collectively known as the carpet sharks because many members have carpet-like patterned markings, includes a number of familiar types of sharks, such as the nurse sharks and whale shark, as well as some unusual species, such as the blind shark. The order is small, with only 39 species in seven genera.
Carpet sharks have two dorsal fins, without spines, and a small mouth that is forward of the eyes. Many have barbels and small gill slits, with the fifth slit overlapping the fourth. The upper lobe of the caudal fin tends to be mostly in line with the body, while the lower lobe is poorly developed, except in the case of the whale shark. While many in the order are small, the whale shark is the largest living fish

Bull Shark

The bull shark, Carcharhinus leucas, also known as the bull whaler, Zambezi shark or informally Zambi in Africa and Nicaragua shark in Nicaragua, is common worldwide in warm, shallow waters along coasts and in rivers. The bull shark is well known for its unpredictable, often aggressive behavior. Many scientists agree that since bull sharks often dwell in shallow waters, they may be more dangerous to humans than any other species of sharks.[1]
Unlike most other marine sharks, bull sharks tolerate fresh water. They can travel far up rivers. As a result, they are probably responsible for the majority of shark attacks on humans that take place near the shore, including many attacks attributed to other species.[2] However, bull sharks are not true freshwater sharks

Bronze Whaler Shark

The copper shark, bronze whaler, or narrowtooth shark, Carcharhinus brachyurus, is a large shark of the Carcharhinidae family, found in subtropical seas and oceans worldwide, except the eastern coast of North America and the northern Indian Ocean. Their length is up to about 3.5 metres and they can weigh up to 300 kilogrammes.
The bronze whaler (its most common name) has a blunt broad snout, narrow bent cusps on the upper teeth, and no interdorsal ridge. They are gray to bronze in color on the back, and white below. The fins are similarly coloured except the pelvic fins, which have dusky tips, and the pectoral fins, which have dusky to black tips.
Bronze whalers are often seen close inshore feeding on schooling fish, such as salmon, frequently within the surf zone but they are also found around offshore islands near deep water where they prey on squid as well as pelagic and bottom-dwelling fish.
Reproduction is viviparous and the female will deliver between seven and twenty live pups. Males live for up to thirty years, and females for up to twenty five. It can be dangerous to spearfishers with recently speared fish, and also towards surfers as its prey is often found in the surf. The bronze whaler is a large and aggressive shark that should be considered very dangerous - it has attacked people, notably along the eastern coast of Australia, but it has not been confirmed in any fatal attacks on humans[1]. It is often confused with the dusky shark.

Broadnose Sevengill Shark

Broadnose Sevengill Shark :
Size: Roughly 10 feet (3m)
Weight: Unknown
Food Sources: Sharks, rays, fish, seals, and carrion
Habitat: Deep waters, up to 135m
Locations: Temperate areas
Interesting Facts: Has 7 gill slits (sharks normally have 5)

Blue Shark

Blue Shark :
Size: Average 6 to 8 feet, biggest 10.5 feet
Weight: 250 to 500 pounds
Food Sources: Mainly small fish and squid
Habitat: Shallow reef areas
Locations: Temperate and subtropical waters
Interesting Facts: Often attacks and eats smaller sharks

Bramble Shark

size: 310 cm TL (male/unsexed; Ref. 247)
Environment: bathydemersal; marine; depth range 10 – 900 m
Gazetteer Western Atlantic: Virginia, Massachusetts, USA; Argentina. Eastern Atlantic: North Sea to Mediterranean, Morocco to Cape of Good Hope, South Africa. Western Indian Ocean: India, Mozambique, South Africa. Western Pacific: Japan, southern Australia, New Zealand. Records from Oman and Kiribati uncertain. Apparently absent in the Eastern Pacific (Ref. 6578).
Morphology: Dorsal spines (total): 0 - 0; Anal spines: 0. The bramble shark Echinorhinus brucus has thorn-like denticles on body which are very large (single denticles up to about 15mm in basal diameter in adults), sparse irregularly distributed and thorn-like with smooth basal margins, some bases fused into compound plates. Dorsal surface dark purplish-grey to brown with white denticles, ventral surface paler; sides and back may have dark spots. Tooth count 20-26/21-26.As with the other member of the family Echinorhinidae, it has a relatively short snout and stout body; two small spineless dorsal fins, close together, towards posterior part of body and originating behind pelvic fin origin. No anal fin and subterminal notch on caudal fin. Small spiracles, very short labial furrows and teeth on both jaws alike, with a central oblique bladelike cusps with up to 3 cusplets on each side (absent in juveniles) (Ref. 247, 6871, 5578).
Biology: A rare (Ref. 26346), large, sluggish, deepwater shark found on continental and insular shelves and upper slopes (Ref. 247). Sometimes found in shallow water (Ref. 247). Feeds on smaller sharks, bony fishes, and crabs (Ref. 247). Ovoviviparous (Ref. 205), with 15-26 young in a litter (26346). Never recorded as attacking people. Sometimes hooked by shore anglers (Ref. 5578). Processed into fishmeal. May be used in traditional medicine in southern Africa (Ref. 5578).

Blacktip Reef Shark

Blacktip Reef Shark :
Size: 213 cm (7 ft) max
Weight: 14 kg (30.9 lbs) max
Food Sources: Small fish, mollusks and crustaceans
Habitat: Tropical waters and reef areas
Locations: All tropical waters worldwide
Interesting Facts: Usually hunt small fish in schools

Basking Shark

The basking shark, Cetorhinus maximus, is the second largest fish, after the whale shark. It is a cosmopolitan species - it is found in all the world's temperate oceans. It is a slow moving and generally harmless filter feeder.
Like other large sharks, basking sharks are at risk of extinction due to a combination of low resilience and overfishing to supply the worldwide market for the shark's fins, flesh and organs.

Angel Shark

This is a family of flat bottom dwelling sharks that consists of 18 species that are very much alike. They look a lot like rays, and skates, except their pectoral fins are not fastened to the head, and their five-gill slits are on the side of the head not the bottom. The mouth is full of small sharp teeth, and is on the end of their snout. The eyes, and spiracles are on top of the head. The largest angel shark ever recorded was 6.5 feet, but they are usually five feet or smaller. The sharks are reddish brown, or sand gray, with white bellies and some have dark brown speckles and splotches.
HABITAT & RANGE: Live along temperate costs all over the world. Some live in shallower water while others can be found more then 4,265 feet deep.
HUNTING HABITS: Angel sharks burrow in the sand during the day and hunt using ambush. Angel sharks eat crabs, fish, squid, and snails.
REPRODUCTION: Ovoviviparous (eggs retained in females body until they hath). Both sexes are mature at around three-feet. The shark's pups are twelve inches at birth. Litters rang from eight to fourteen pups.
DANGER TO MAN: They are only a threat if caught in nets, harassed, or stepped on.