Instruct: Given a question, retrieve relevant documents that answer the question.
Query: Do great white sharks migrate to australia?
Stephan Swanson came to prominence as a marine researcher when he successfully placed the satellite transmitter on the famous Great white shark Nicole, the first great white shark ever to be tracked on a 20,000 kilometer migration from South Africa to Australia and back. Due to his ability to handle large marine predators, such as the great white shark, he was contracted as an expedition biologist to travel to Guadeloupe and place satellite transmitters on the dorsal fins of Great Whites. His historical capture and release of a 5m long, 1800 kilogram great white shark is documented in the National Geographic Marine Special "Ultimate Shark".
Most shrike species have a Eurasian and African distribution, with just two breeding in North America (the loggerhead and great grey shrikes). No members of this family occur in South America or Australia, although one species reaches New Guinea. The shrikes vary in the extent of their ranges, with some species such as the great grey shrike ranging across the Northern Hemisphere to the Newton's fiscal which is restricted to the island of São Tomé.
The longcomb sawfish is native to tropical and subtropical waters in the western and central Indo-Pacific. Historically its distribution covered almost and it ranged from South Africa, north to the Red Sea and Persian Gulf, east to the South China Sea, through Southeast Asia to Australia. In Australia, it ranged from Shark Bay, along the northern part of the country, and south to Jervis Bay on the eastern coast. Today it has disappeared from much of its historical range. It can live in colder waters than its relatives, as also evident by the range in Australia where it occurs further south than the other species of sawfish.
At present, hang baits are illegal off Isla Guadalupe and reputable dive operators do not use them. Operators in South Africa and Australia continue to use hang baits and pinniped decoys. In South Australia, playing rock music recordings underwater, including the AC/DC album "Back in Black" has also been used experimentally to attract sharks.
Swells dropped to 1–1.5 m on 28 June 2011, allowing more netting of sardines. Sardines were netted at Amanzimtoti; on the main beach and at Chain Rocks. A 22-year-old American marine biology student (research diver) named Paulo Edward Stanchi was attacked by a large dusky shark while diving at Aliwal Shoal Marine Protected Area. The group of divers had encountered a pocket of sardines when a 3 m long dusky shark bit Mr Stanchi on his left leg and hands. Mr Stanchi managed to free himself from the shark, and was treated on the diving boat before being transported to Rocky Bay, where medics stabilised him. He was then airlifted to Nkosi Albert Luthuli Hospital, where he underwent surgery. Dusky sharks generally live offshore, but come closer to the shore during the sardine run. The annual sardine run allowed more dusky sharks in the Aliwal Shoal MPA than usual, but there was no reason for them to show any more interest in divers than usual. Mr Stanchi had been wearing split fins with black and grey stripes, and this may have looked like a small shoal of fish to the shark. Meanwhile, a woman in her 40s broke her leg in the frenzy at Amanzimtoti when the sardines were netted. The woman is believed to have been trying to get some of the sardines when she "stepped wrong" and fractured her leg. Paramedics stabilized her before transporting her to hospital.
Sawfish are popular in public aquariums, but require very large tanks. In a review of 10 North American and European public aquariums that kept sawfish, their tanks were all very large and ranged from about . Individuals in public aquariums often function as "ambassadors" for sawfish and their conservation plight. In captivity they are quite robust, appear to grow faster than their wild counterparts (perhaps due to consistent access to food) and individuals have lived for decades, but breeding them have proven difficult. In 2012, four smalltooth sawfish pups were born at Atlantis Paradise Island in the Bahamas and this remains the only time a member of this family has been successfully bred in captivity (unsuccessful breeding attempts had happened earlier at the same facility, including a miscarriage in 2003). Nevertheless, it is hoped that this success may be the first step in a captive breeding program for the threatened sawfish. It is speculated that seasonal variations in water temperature, salinity and photoperiod are necessary to encourage breeding. Artificial insemination, as already has been done in a few captive sharks, is also being considered. Tracking studies indicate that if sawfish are released to the wild after spending a period in captivity (for example, if they outgrow their exhibit), they rapidly adopt a movement pattern similar to that of fully wild sawfish.
With a gestation period estimated at up to 22–24 months and a one-year resting period between pregnancies, female dusky sharks bear at most one litter of young every three years. The litter size ranges from 3 to 16, with 6 to 12 being typical, and does not correlate with female size. Sharks in the western Atlantic tend to produce slightly smaller litters than those from the southeastern Atlantic (averaging 8 versus 10 pups per litter). Depending on region, birthing may occur throughout the year or over a span of several months: newborn sharks have been reported from late winter to summer in the northwestern Atlantic, in summer and fall off Western Australia, and throughout the year with a peak in fall off southern Africa. Females move into shallow inshore habitats such as lagoons to give birth, as such areas offer their pups rich food supplies and shelter from predation (including from their own species), and leave immediately afterward. These nursery areas are known along the coasts of KwaZulu-Natal, southwestern Australia, western Baja California, and the eastern United States from New Jersey to North Carolina.
The island is known for its diversity of mammalian fauna, including several species now extinct or greatly reduced on mainland Australia. 13 mammal species exist on the island, including the spectacled hare-wallaby, burrowing bettong (or boodie), golden bandicoot, black-flanked rock-wallaby, Barrow Island euro and Barrow Island mouse ("Pseudomys nanus ferculinus"). The island is also home to 43 species of terrestrial reptiles including a variety of dragons, legless lizards, geckos, skinks, snakes and monitors. The most recognisable of these is probably the perentie, Australia's biggest lizard and the island's top predator. The island represents important turtle nesting habitat for the green turtle and flatback sea turtle.
The Australian coast is visited by six species of sea turtle: the flatback, green sea, hawksbill, olive ridley, loggerhead and the leatherback sea turtles; all are protected in Australian waters. There are 35 species of Australian freshwater turtles from eight genera of the family Chelidae. The pig-nosed turtle is the only Australian turtle not of that family. Australia is the only continent without any living species of land tortoise.
Australia is the only continent where venomous snakes outnumber their non-venomous cousins. Australian snakes belong to seven families. Of these, the most venomous species, including the fierce snake, eastern brown snake, taipan and eastern tiger snake are from the family Elapidae. Of the 200 species of elapid, 86 are found only in Australia. Thirty-three sea snakes from family Hydrophiidae inhabit Australia's northern waters; many are extremely venomous. Two species of sea snake from the Acrochordidae also occur in Australian waters. Australia has only 11 species from the world's most significant snake family Colubridae; none are endemic, and they are considered to be relatively recent arrivals from Asia. There are 15 python species and 31 species of insectivorous blind snake.
There are more than 700 species of lizards in Australia with representatives of five families. There are over 130 species in 20 genera of gecko found throughout the Australian continent. The Pygopodidae is a family of limbless lizards endemic to the Australian region; all 39 species from seven genera occur in Australia. The Agamidae or dragon lizards are represented by 70 species in 14 genera, including the thorny devil, bearded dragon and frill-necked lizard. There are 30 species of monitor lizard, family Varanidae, in Australia, where they are commonly known as goannas. The largest Australian monitor is the perentie, which can reach up to 2 m in length. There are about 450 species of skink from more than 40 genera, comprising more than 50% of the total Australian lizard fauna; this group includes the blue-tongued lizards.
According to the GBRMPA in 2014, the most significant threat to the status of the Great Barrier Reef is climate change, due to the consequential rise of sea temperatures, gradual ocean acidification and an increase in the number of "intense weather events". Hughes writes of "the demonstrable failure of the state and Commonwealth" to address the issue of climate change in his August 2014 article. Furthermore, a temperature rise of between two and three degrees Celsius would result in 97% of the Great Barrier Reef being bleached every year.
In Australia (mainly northern; however, box jellyfish can live in subtropical waters as far south as Sydney, with "Carybdea marsupialis" being recorded as far south as Bermagui, Sapphire Coast) the highest risk period for the box jellyfish is between October and May, but stings and specimens have been reported all months of the year. Similarly, the highest risk conditions are those with calm water and a light, onshore breeze; however, stings and specimens have been reported in all conditions.
Adults are primarily found in estuaries and marine waters to a depth of , but mostly less than . Nevertheless, the species does appear to have a greater affinity for freshwater habitats than the smalltooth sawfish ("P. pectinata"), green sawfish ("P. zijsron"), and dwarf sawfish ("P. clavata"). Largetooth sawfish from the population in Lake Nicaragua appear to spend most, if not all, of their life in freshwater, but tagging surveys indicate that at least some do move between this lake and the sea. Captive studies show that this euryhaline species can thrive long-term in both salt and freshwater, regardless of its age, and that an acclimation from salt to freshwater is faster than the opposite. In captivity they are known to be agile (even swimming backwards), have an unusual ability to "climb" with the use of the pectoral fins and they can jump far out of the water; a individual jumped to a height of . It has been suggested that this may be adaptions for traversing medium-sized waterfalls and rapids when moving upriver. They are generally found in areas with a bottom consisting of sand, mud or silt. The preferred water temperature is between , and or colder is lethal.
In July 2017 UNESCO published in a draft decision, expressing serious concern about the impact of coral bleaching on the Great Barrier Reef. The draft decision also warned Australia that it will not meet the targets of the Reef 2050 report without considerable work to improve water quality.
The rough-skinned newt ("Taricha granulosa") is a newt known for its strong poison. Habitats of rough-skinned newts are found throughout the West Coast of the United States and British Columbia. Their range extends south to Santa Cruz, California and north to Alaska.
The dusky shark is a generalist that takes a wide variety of prey from all levels of the water column, though it favors hunting near the bottom. A large individual can consume over a tenth of its body weight at a single sitting. The bite force exerted by a long dusky shark has been measured at over the area at the tip of a tooth. This is the highest figure thus far measured from any shark, though it also reflects the concentration of force at the tooth tip. Dense aggregations of young sharks, forming in response to feeding opportunities, have been documented in the Indian Ocean.
The closest living relative of the Galapagos giant tortoise is the small Chaco tortoise from South America, although it is not a direct ancestor. Scientists believe the first tortoises arrived to Galapagos 2–3 million years ago by drifting 600 miles from the South American coast on vegetation rafts or on their own. They were already large animals before arriving in Galapagos. Colonizing the eastern-most islands of Española and San Cristóbal first, they then dispersed throughout the archipelago, eventually establishing about 16 separate populations on ten of the largest Galapagos Islands. Currently there are only 10 species of Galapagos Giant Tortoises left of the original 16 species. During the 16th and 17th centuries, the Galápagos were frequented by buccaneers preying on Spanish treasure ships. Filling a ship's hold with tortoises was an easy way to stock up on food, a tradition that was continued by whalers in the centuries that followed: "whaling skippers were almost lyrical in their praise of tortoise meat, terming it far more delicious than chicken, pork or beef'. They said the meat of the giant tortoise was 'succulent meat and the oil from their bodies as pure as butter, but best of all, the giants could hibernate in a ship's damp for a year or more." The tortoises also conveniently held water in their neck that could be used as drinking water.
The redback spider is widespread across Australia. The current distribution reported by the World Spider Catalogue includes Southeast Asia and New Zealand. Colonies and individuals have been found elsewhere, including Japan, England, Belgium, the United Arab Emirates and Iran. It was believed at one time that the redback may have been introduced to Australia, because when it was first formally described in 1870, it appeared to be concentrated around sea ports. However, an earlier informal description (1850) from the Adelaide Hills is now known, and names in Australian Aboriginal languages also show that it was present well before European settlement. Its original range is thought to be a relatively small arid part of South Australia and Western Australia. Its spread has been inadvertently aided by modern buildings, which often provide habitats conducive to redback populations. The close relationship between the redback and the New Zealand katipo also supports the native status of both in their respective countries.
In addition, the population of blue whales occurring off Chile and Peru may also be a distinct subspecies. Some Antarctic blue whales approach the eastern South Atlantic coast in winter, and occasionally, their vocalizations are heard off Peru, Western Australia, and in the northern Indian Ocean. In Chile, the Cetacean Conservation Center, with support from the Chilean Navy, is undertaking extensive research and conservation work on a recently discovered feeding aggregation of the species off the coast of Chiloe Island in the Gulf of Corcovado (Chiloé National Park), where 326 blue whales were spotted in 2007. In this regions, it is normal for blue whales to enter Fiords. Whales also reach southern Los Lagos, such as off Caleta Zorra, live along with other rorquals.
In addition to commercial shark fisheries, dusky sharks are also caught as bycatch on longlines meant for tuna and swordfish (and usually kept for its valuable fins), and by recreational fishers. Large numbers of dusky sharks, mostly juveniles, are caught by sport fishers off South Africa and eastern Australia. This shark was once one of the most important species in the Florida trophy shark tournaments, before the population collapsed.
Australia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania and numerous smaller islands. It is the largest country in Oceania and the world's sixth-largest country by total area. The neighbouring countries are Papua New Guinea, Indonesia and East Timor to the north; the Solomon Islands and Vanuatu to the north-east; and New Zealand to the south-east. The population of / 1000000 round 0 million is highly urbanised and heavily concentrated on the eastern seaboard. Australia's capital is Canberra, and its largest city is Sydney. The country's other major metropolitan areas are Melbourne, Brisbane, Perth and Adelaide.
The dwarf and largetooth sawfish are strictly warm-water species that generally live in waters that are and respectively. The green and smalltooth sawfish also occur in colder waters, in the latter down to , as illustrated by their (original) distributions that ranged further north and south of the strictly warm-water species. Sawfish are bottom-dwellers, but in captivity it has been noted that at least the largetooth and green sawfish readily take food from the water surface. Sawfish are mostly found in places with soft bottoms such as mud or sand, but may also occur over hard rocky bottoms or at coral reefs. They are often found in areas with seagrass or mangrove.
It should be noted that the impact of shark culling is minor compared to bycatch from Commercial fishing. On average 15 Great white sharks are caught by the NSW and Queensland shark control programme each year, compared to 186 caught in Australia from other activities. Australia's commercial shark fishing industry is catching over 1200 tonne of shark each year, of which 130 are Great white sharks. The NSW prawn trawling industry alone results in 64 tonne of shark as bycatch each year, with two thirds dying. Tuna and swordfish longline fishing off the coast of South Africa reported 39,000 to 43,000 sharks killed each year between 1995 and 2005. "Sharksavers" estimates that in total 50 million sharks are caught unintentionally each year as bycatch by the commercial fishing industry.
However it should be noted that shark and bycatch mortality from drum lines is minor compared to Commercial fishing. On average 15 Great white sharks are caught by the NSW and Queensland shark control programme each year, compared to 186 caught in Australia from other activities. Australia's commercial shark fishing industry is catching over 1200 tonne of shark each year, of which 130 are Great white sharks. The NSW prawn trawling industry alone results in 64 tonne of shark as bycatch each year, with two thirds dying. Tuna and swordfish longline fishing off the coast of South Africa reported 39,000 to 43,000 sharks killed each year between 1995 and 2005. "Sharksavers" estimates that in total 50 million sharks are caught unintentionally each year as bycatch by the commercial fishing industry.
However bycatch from shark nets is minor compared to bycatch from other activities. On average 15 Great white sharks are caught by the NSW and Queensland shark control programme each year, compared to 186 caught in Australia from other activities. Australia's commercial shark fishing industry is catching over 1200 tonne of shark each year, of which 130 are Great white sharks. The NSW prawn trawling industry alone results in 64 tonne of shark as bycatch each year, with two thirds dying. Tuna and swordfish longline fishing off the coast of South Africa reported 39,000 to 43,000 sharks killed each year between 1995 and 2005. "Sharksavers" estimates that in total 50 million sharks are caught unintentionally each year as bycatch by the commercial fishing industry.
Fox, along with his son, Andrew, after more than 40 years, still continue to run Rodney Fox Great White Shark Expeditions, a shark cage diving operation to view great white sharks in the wild off Southern Australia. This operation also acts as a platform for much needed further research of great white sharks as well as encouraging quality natural history documentaries on the species.