Geography | |
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Location | Atlantic Ocean |
Coordinates | 34°8′10″S18°34′58″E / 34.13611°S 18.58278°E |
Administration | |
South Africa |
Seal Island (formerly known as Witte Klip, meaning "White Rock") is a small land mass located 5.7 kilometres (3.5 miles) off the northern beaches of False Bay, near Cape Town in South Africa. The island is so named because of the great number of Cape fur seals that occupy it. It is 5 acres (2.0 hectares) in area and home to 64,000 cape fur seals. [1] It is also home to seabirds, and it is likely that non-marine species fly there to breed as well . The island is an outcrop of Cape granite and rises no more than about 4 to 6 metres (13 to 20 feet) above the high tide mark. The island is long and narrow – 800 by 50 metres (2,620 by 160 feet). There is no vegetation, soil of any significance, or beach.
A radar mast was built on the island during World War II by a crew who lived in prefabricated huts for the duration of the construction but this tower gradually succumbed to corrosion and was blown over in a winter storm in 1970. All that remains of it is rusty, twisted metal. The ruins of a few huts and other structures from the sealing and guano-collection era (first half of the 20th century) have remained on the island. Some rock inscriptions made by sealers in the 1930s are still evident.[ citation needed ]
Besides the Cape fur seal, the Brown fur seal, [2] occurs here and the dense population of seals at certain times of the year attracts the seal's main predator, the great white shark. [1] Seal Island and the adjacent waters provide rare opportunities for those who wish to witness attacks by great whites on the Cape fur seal and to observe social interactions amongst creatures of both species. The island has become famous for the size of the sharks, and for their favoured way of catching their prey – a shark launching an attack will come up from underneath and hurl itself out of the water with the seal in its mouth. It has been shown that if the seals enter the "Ring of Death" (where the sharks circle the island) on the surface instead of at the murky bottom, they are more likely to be picked off by the faster and more aggressive great white.
Since 2001, Seal Island, False Bay has been popularized by the Discovery Channel series Air Jaws, which features the breaching behavior of Great Whites near the island. A 2019 sequel, "Air Jaws Strikes Back" names a "second Seal Island", this time located in Mossel Bay on the southeast coast of South Africa.[ citation needed ]
The great white shark, also known as the white shark, white pointer, or simply great white, is a species of large mackerel shark which can be found in the coastal surface waters of all the major oceans. It is the only known surviving species of its genus Carcharodon. The great white shark is notable for its size, with the largest preserved female specimen measuring 5.83 m (19.1 ft) in length and around 2,000 kg (4,400 lb) in weight at maturity. However, most are smaller; males measure 3.4 to 4.0 m, and females measure 4.6 to 4.9 m on average. According to a 2014 study, the lifespan of great white sharks is estimated to be as long as 70 years or more, well above previous estimates, making it one of the longest lived cartilaginous fishes currently known. According to the same study, male great white sharks take 26 years to reach sexual maturity, while the females take 33 years to be ready to produce offspring. Great white sharks can swim at speeds of 25 km/h (16 mph) for short bursts and to depths of 1,200 m (3,900 ft).
A shark attack is an attack on a human by a shark. Every year, around 80 unprovoked attacks are reported worldwide. Despite their rarity, many people fear shark attacks after occasional serial attacks, such as the Jersey Shore shark attacks of 1916, and horror fiction and films such as the Jaws series. Out of more than 500 shark species, only three are responsible for a double-digit number of fatal, unprovoked attacks on humans: the great white, tiger, and bull. The oceanic whitetip has probably killed many more shipwreck and plane crash survivors, but these are not recorded in the statistics. Humans are not part of a shark's normal diet. Sharks usually feed on small fish and invertebrates, seals, sea lions, and other marine mammals. A shark attack will usually occur if the shark feels curious or confused.
The brown fur seal, also known as the Cape fur seal, and Afro-Australian fur seal, is a species of fur seal.
The cookiecutter shark, also called the cigar shark, is a species of small squaliform shark in the family Dalatiidae. This shark lives in warm, oceanic waters worldwide, particularly near islands, and has been recorded as deep as 3.7 km (2.3 mi). It migrates vertically up to 3 km (1.9 mi) every day, approaching the surface at dusk and descending with the dawn. Reaching only 42–56 cm (16.5–22 in) in length, the cookiecutter shark has a long, cylindrical body with a short, blunt snout, large eyes, two tiny spineless dorsal fins, and a large caudal fin. It is dark brown, with light-emitting photophores covering its underside except for a dark "collar" around its throat and gill slits.
The Farallon IslandsFA-ra-lon, or Farallones, are a group of islands and sea stacks in the Gulf of the Farallones, off the coast of San Francisco, California, United States. The islands are also sometimes referred to by mariners as the Devil's Teeth Islands, in reference to the many treacherous underwater shoals in their vicinity. The islands lie 30 miles (48 km) outside the Golden Gate and 20 miles (32 km) south of Point Reyes, and are visible from the mainland on clear days. The islands are part of the City and County of San Francisco. The only inhabited portion of the islands is on Southeast Farallon Island (SEFI), where researchers from Point Blue Conservation Science and the U.S. Fish and Wildlife Service stay. The islands are closed to the public.
The broadnose sevengill shark is the only extant member of the genus Notorynchus, in the family Hexanchidae. It is recognizable because of its seven gill slits, while most shark species have five gill slits, with the exception of the members of the order Hexanchiformes and the sixgill sawshark. This shark has a large, thick body, with a broad head and blunt snout. The top jaw has jagged, cusped teeth and the bottom jaw has comb-shaped teeth. Its single dorsal fin is set far back along the spine towards the caudal fin, and is behind the pelvic fins. In this shark the upper caudal fin is much longer than the lower, and is slightly notched near the tip. Like many sharks, this sevengill is counter-shaded. Its dorsal surface is silver-gray to brown in order to blend with the dark water and substrate when viewed from above. In counter to this, its ventral surface is very pale, blending with the sunlit water when viewed from below. The body and fins are covered in a scattering of small black & white spots. In juveniles, their fins often have white margins.
False Bay is a body of water in the Atlantic Ocean between the mountainous Cape Peninsula and the Hottentots Holland Mountains in the extreme south-west of South Africa. The mouth of the bay faces south and is demarcated by Cape Point to the west and Cape Hangklip to the east. The north side of the bay is the low-lying Cape Flats, and the east side is the foot of the Hottentots Holland Mountains to Cape Hangklip which is at nearly the same latitude as Cape Point. In plan the bay is approximately square, being roughly the same extent from north to south as east to west, with the southern side open to the ocean. The seabed generally slopes gradually down from north to south, and is mostly fairly flat unconsolidated sediments. Much of the bay is off the coast of the City of Cape Town, and it includes part of the Table Mountain National Park Marine Protected Area and the whole of the Helderberg Marine Protected Area. The name "False Bay" was applied at least three hundred years ago by sailors returning from the east who confused Cape Point and Cape Hangklip, which are somewhat similar in profile when approached from the southeast.
The Jersey Shore shark attacks of 1916 were a series of shark attacks along the coast of New Jersey, in the United States, between July 1 and 12, 1916, in which four people were killed and one critically injured. The incidents occurred during a deadly summer heat wave and polio epidemic in the United States that drove thousands of people to the seaside resorts of the Jersey Shore. Since 1916, scholars have debated which shark species was responsible and the number of animals involved, with the great white shark and the bull shark most frequently cited.
Bloubergstrand is a seaside suburb of the City of Cape Town, South Africa, along the shores of Table Bay, 15 kilometres (9.3 mi) due north of the city centre of Cape Town. The name Bloubergstrand literally means "blue mountain beach" in Afrikaans, and is derived from Blaauwberg, a nearby hill. Bloubergstrand is mainly a residential area, and attracts large numbers of visitors especially kitesurf enthusiasts. The beach at Bloubergstrand is a popular location for a classic view of Table Mountain across the bay and is one of the world's top kitesurf destinations. Robben Island is located 6.9 kilometres (4.3 mi) west of the coast of Bloubergstrand.
The 1992 cageless shark-diving expedition was the world's first recorded intentionally cageless dive with great white sharks, contributing to a change in public opinions about the supposed ferocity of these animals.
The Red Triangle is the colloquial name of a roughly triangle-shaped region off the coast of northern California, extending from Bodega Bay, north of San Francisco, out slightly beyond the Farallon Islands, and down to the Big Sur region, south of Monterey. The area has a very large population of marine mammals, such as elephant seals, harbor seals, sea otters and sea lions, which are favored prey of great white sharks. Around thirty-eight percent of recorded great white shark attacks on humans in the United States have occurred within the Red Triangle—eleven percent of the worldwide total. The area encompasses the beaches of the heavily populated San Francisco Bay Area, and many people enjoy surfing, windsurfing, swimming and diving in these waters.
The leopard catshark is a species of catshark, and part of the family Scyliorhinidae, endemic to the coastal waters of South Africa. Abundant in inshore waters under 20 m (66 ft) deep, this bottom-dweller favors rocky reefs, kelp beds, and sandy flats. Growing to a length of 84 cm (33 in), the leopard catshark has a stout body with two dorsal fins placed well back, and a short head and tail. It is extremely variable in color and pattern, with individuals ranging from almost white to black and covered by diverse patterns of black spots, blotches, rosettes, and/or lines. The color pattern changes with age and some forms seem to be location-specific, suggesting the presence of multiple distinct, local populations. In the past, some of the more distinct color forms have been described as different species.
The puffadder shyshark, also known as the Happy Eddie, is a species of catshark, belonging to the family Scyliorhinidae, endemic to the temperate waters off the coast of South Africa. This common shark is found on or near the bottom in sandy or rocky habitats, from the intertidal zone to a depth of 130 m (430 ft). Typically reaching 60 cm (24 in) in length, the puffadder shyshark has a slender, flattened body and head. It is strikingly patterned with a series of dark-edged, bright orange "saddles" and numerous small white spots over its back. The Natal shyshark, formally described in 2006, was once considered to be an alternate form of the puffadder shyshark.
Michael Rutzen is a South African conservationist, film maker, and cage diving operator.
Ryan Johnson is a marine biologist specializing in researching sharks. He is best known for the shark documentaries that he features in and hosts.
Samson Gabriel Dyer aka Sampson Dyers was an African-American man noted for his association with Dyer Island off the Cape Agulhas coast of South Africa.
South African born Chris Fallows is an expert on great white sharks and their hunting habits. He has amassed the largest database of predatory events involving great white sharks in False Bay and was the first member of the scientific community to observe the breaching behaviour.
A total of 24 people have been killed by sharks in South Australian waters since the establishment of the colony in 1836. Prior to 2014, there had been 82 recorded shark attacks in South Australia. 20 of those have involved a single fatality. Victims were involved in a range of aquatic activities, including surfing, diving, spear-fishing, snorkeling, boating and swimming. Six of the fatalities occurred off the coast of greater metropolitan Adelaide, with the remainder distributed across South Australia's extensive coastline. Many of the fatal attacks have been attributed to great white sharks.
Air Jaws is a series of fifteen TV specials about great white sharks that have aired on Discovery Channel's Shark Week. The specials are mainly filmed in the Indian Ocean off the coast of South Africa, many on Seal Island in False Bay, near Cape Town, or in Mossel Bay. All fifteen specials were produced and directed by Jeff Kurr. The third episode "Ultimate Air Jaws" was nominated for an Emmy, Outstanding Individual Achievement in a Craft: Cinematography - Nature in 2011.
Port and Starboard are a pair of adult male orcas notable for preying on great white sharks off the coast of South Africa. The duo are identified as having rare and distinct collapsed dorsal fins and they are named for the nautical terms, as Port's fin collapses left and Starboard's collapses right. Port and Starboard are part of a distinctive "flat-toothed" ecotype present around South Africa.