Paradise

Great white sharks are at the very top of the marine food chain. Feared as man-eaters, they are only responsible for about 5-10 attacks a year, which are rarely fatal. Great whites are ultimate predators. Powerful streamlined bodies and a mouth full of terrifyingly sharp, serrated teeth, combine with super senses that can detect a single drop of blood from over a mile away. Hiding from a great white isn't an option as they can detect and home in on small electrical discharges from hearts and gills. Unlike most other sharks, live young are born that immediately swim away.

The great white shark, Carcharodon carcharias, also known as the great white, white pointer, white shark, or white death, is a species of large lamniform shark which can be found in the coastal surface waters of all the major oceans. The great white shark is mainly known for its size, with the largest individuals known to have approached or exceeded 6.1 m (20 ft) in length, and 2,268 kg (5,000 lb) in weight. This shark reaches its maturity around 15 years of age and can have a life span of over 30 years.

The great white shark is arguably the world's largest known extant macropredatory fish, and is one of the primary predators of marine mammals. It is also known to prey upon a variety of other marine animals, including fish and seabirds. It is the only known surviving species of its genus Carcharodon, and is ranked first in having the most attacks on humans. The IUCN list the great white shark as a vulnerable species, while it is included in Appendix II of CITES. The bestselling novel Jaws by Peter Benchley and the subsequent blockbuster film by Steven Spielberg depicted the great white shark as a "ferocious man eater". In reality, humans are not the preferred prey of the great white shark.

Basking sharks are one of the largest sharks of the world's temperate oceans. Only the mighty whale shark is bigger. Despite a superficial similarity to the fearsome great white shark and a massive jaw one metre wide, basking sharks are actually harmless filter feeders. They use more than 5,000 gill rakers to strain plankton from around 1.5 million litres of water per hour. Basking sharks are born travellers, covering large distances in search of food, at the very leisurely pace of only three miles per hour. There is only one species of basking shark.

The basking shark (Cetorhinus maximus) is the second largest living fish, after the whale shark, and the second of three plankton-eating sharks, the other two being the whale shark and megamouth shark. It is a cosmopolitan migratory species, found in all the world's temperate oceans. It is a slow moving filter feeder and has anatomical adaptations to filter feeding, such as a greatly enlarged mouth and highly developed gill rakers. The shape of its snout is conical and the gill slits extend around the top and bottom of its head. The gill rakers are dark and bristle-like and are used to catch plankton as water filters through the mouth and over the gills. The basking shark is usually greyish-brown in color with mottled skin. The caudal (tail) fin has a strong lateral keel and a crescent shape. The teeth of the basking shark are very small and numerous and often number one hundred per row. The teeth themselves have a single conical cusp, are curved backwards and are the same on both the upper and lower jaws.

Basking sharks are a migrating species and are believed to overwinter in deep waters. They may occur in either small schools or alone. Small schools in the Bay of Fundy and the Hebrides have been seen swimming nose to tail in circles in what may be a form of mating behavior. Despite their large size and threatening appearance, basking sharks are not aggressive and are harmless to people. It has long been a commercially important fish, as a source of food, shark fin, animal feed, and shark liver oil. Overexploitation has reduced its populations to the point where some have disappeared and others need protection.

The shortfin mako (Isurus oxyrinchus) is believed to be the fastest-swimming of all sharks, thought to be capable of attaining bursts of speed of up to 35 kilometres per hour, and famed for making spectacular leaps of up to six metres out of the water. The shortfin makos’ high tail produces maximum thrust to propel the shark rapidly forward, both in extreme bursts of speed, and for sustained, long-distance travel. The shortfin mako also has a heat exchange circulatory system that enables the body to be warmer than surrounding water, and thus maintain a high level of activity. This large, stream-lined shark has a distinctively crescent-shaped caudal fin, a long, conical snout, large black eyes and razor-sharp, blade-like teeth. The upper body is a brilliant metallic blue, while the underside is snow-white, with older, larger specimens tending to be darker with reduced white areas. Juveniles are therefore generally paler than adults, and also differ by possessing a clear black mark on the tip of their snout. The shortfin mako can be distinguished from the only other mako shark, the longfin mako (Isurus paucus), not only by having shorter pectoral fins, but also by the white colouration on the underside of the snout and around the mouth, which is darkly pigmented in the longfin mako.

Given this shark’s relative notoriety, particularly among anglers, surprisingly little is known of its biology. Reproductive knowledge of the solitary shortfin mako is sparse, largely because pregnant females usually abort embryos upon capture, making study difficult. Reproduction is ovoviviparous, with embryos being nourished in the uterus by a yolk sac rather than placenta. Once the young have hatched, uterine cannibalism known as oophagy occurs, in which the growing young feed on unfertilised or less-developed eggs. Litters of between 4 and 25 live young are born in the late winter and early spring, after a 15 to 18 month gestation period. This is followed by an initial relatively fast growth rate. Females are believed to rest for 18 months after birth before conceiving again. Females appear to become sexually mature at around 17 to 19 years of age and males mature around 7 to 9 years. The maximum known age of a shortfin mako is 32 years.

The shortfin mako primarily feeds on a wide variety of fishes, such as swordfish, tuna, mackerel, cod, sea bass, and even other sharks, including blue sharks (Prionace glauca), grey sharks (Carcharhinus species) and hammerheads (Sphyrna species). However, squid, sea turtle heads, and a ‘porpoise’ (probably a pelagic dolphin) have also been found in the stomachs of these sharks. This is a wide-ranging shark found in tropical and temperate waters throughout the world’s oceans. In the Western Atlantic, the shortfin mako occurs from the Gulf of Maine to southern Brazil, including the Gulf of Mexico and the Caribbean. In the Eastern Atlantic, the distribution ranges from Norway, down past the British Isles, the Mediterranean, the Ivory Coast and Ghana to South Africa. In the Indo-Pacific, the shortfin mako shark is found from East Africa and the Red Sea to Hawaii, including waters around Pakistan, India, Korea, Japan, Indonesia, Australia, Tasmania, and New Zealand. In the Eastern Pacific, the range includes waters south of the Aleutian Islands and from Southern California, USA, to Chile. The shortfin mako is usually pelagic, but can sometimes be found close inshore. Although normally occupying surface waters down to around 150 metres, this shark has been recorded at depths of up to 740 metres. There is evidence to suggest that this species migrates seasonally to warmer waters.