However, the number of deaths in is a record in modern times, and the highest since shark nets and other intended deterrents were introduced in the s. Historically, dying from a shark bite is not common. In over a century of records, the shark attack mortality rate is 0. One of the seven deaths this year involved a man who was spearfishing near Fraser Island in Queensland.
This was classified as a "provoked" attack - because the man may have attracted the shark through his fishing activity. The six other fatal attacks, however, were unprovoked. That's also a record since , though there were four as recently as Researchers can't fully explain why unprovoked attacks happen, saying historically low numbers of fatalities have made it difficult to discern causes or trends.
In some cases, witnesses to attacks have reported seeing shoals of fish in the area - something that can attract sharks. Ultimately, though, much is made of luck and circumstance. He noted that most victims were surfers, not swimmers, which meant they were often out in deeper waters and in more inaccessible areas. Of the four deaths in , two occurred in remote locations. Many of this year's victims have been surfers. Last year, Associate Prof Hart and his colleagues studied over a century of shark file data and temperature and rain records.
They concluded that climatic and oceanographic forecasts could help suggest when and where attacks might be more likely to happen. The team identified potential weather triggers at hotspots like northern New South Wales, where two deaths have happened this year. In that location the risk apparently peaked when there was significant rainfall. The rain would flush nutrients into the sea, creating a pocket of cooler, turbid water at river mouths and along the coast.
He said this was also associated with a stronger East Australian Current, which creates distinct temperature differences in the ocean.
Australia's Bureau of Meteorology has recently declared a La Nina, a weather pattern which typically increases rainfall across the nation's east. Scientists know that climate change is affecting ocean current movements and weather patterns.
The reasons are unclear, but other experts argue humans are to blame for an increase in attacks. If you do encounter a shark, there are steps you can take to minimise the risk of being attacked. Sometimes culls of sharks are mooted after attacks, but they have little effect on minimising the threat and provoke outrage from conservationists.
In other cases shark repellents, based on reactions to smells tastes and sounds have been developed. Carcharodon megalodon , the largest shark ever to have lived 16 — 1. Fossil evidence suggests it grew to a length of 16m, had jaws that were more than 2m wide and sported teeth measuring up to 21cm.
In comparison, the great white grows to 6m, weighs up to 2. It favours cool, shallow, temperate seas, and is most commonly found in southern Australian waters from Exmouth, WA, to southern Queensland. Feeds on fish and marine mammals such as seals. Highly migratory and found in tropical and subtropical oceans worldwide, it appears alone or in large groups. It filterfeeds on plankton, but also eats prawns, crabs, schooling fish and occasionally tuna and squid. With a pig-like snout, conspicuous ridges above the eyes and a harness-like pattern across the shoulder, this is a distinctive-looking shark.
Frequently seen by divers in rocky gullies and caves throughout its range — south from the Queensland-NSW border to the Houtman Abrolhos, WA, including Tasmania — it feeds at night on starfish, sea urchins, sea cucumbers and molluscs. It poses no threat to humans unless provoked.
Immediately recognisable by its long tail — which it uses to herd and stun squid and schools of fish — this shark can leap up to 6m out of the water. While not aggressive towards humans, this is a large, powerful shark. This harmless reef-dweller is charming in appearance and nature. It eats gastropods, crustaceans and fish, and is found in Australian waters north from Sydney around to Port Gregory, WA.
The tiger shark is the tropical equivalent of the great white and highly dangerous. A true scavenger, it eats turtles, seals, whales, jellyfish and stingrays, plus livestock and people unlucky enough to fall overboard. Wearing a patterned suit that blends in with the reef floor, this bottom-dweller inhabits tropical waters from Port Hedland, WA, to Bundaberg, Queensland, as well as Indonesia and New Guinea. It feeds on fish and invertebrates, and can be dangerous when provoked or disturbed.
It eats everything from fishes and squid to whales, sea birds and turtles. Many open-ocean attacks on humans after air or sea disasters are attributed to it. Although fairly common and wideranging in the tropics, it is fished and has a long gestation time, making it potentially vulnerable. Protected in NSW and Queensland, the grey nurse looks fearsome thanks to its exposed, razor-sharp teeth, but is not considered dangerous.
It eats fish, rays, squid and crustaceans, and is often seen near the sea floor. This aggressive species has powerful jaws and eats almost anything: other sharks, dolphins, rays, fish, turtles, birds and molluscs. It can penetrate freshwater river systems and has been known to take cattle, dogs and people. This species is potentially dangerous to humans and often occurs in pairs.
Purchase biodegradable and chemical-free products that do not harm our environment, and support recycling efforts to keep harmful materials like plastic from entering the water supply.
This entangles and kills birds, fish, turtles, dolphins, small sharks and whales. Organise your classroom, school club, or organisation to clean litter from rivers, creeks, estuaries, and beaches. We kill them by the millions. They kill a handful of us each year. Use caution when swimming at dawn and dusk near seal colonies. This is where and when Great Whites feed. Spread the truth about sharks.
They need our help. Stop the rare fatal attack covering the facts. Great Whites are a magnificent species playing a vital role in our oceans.
We must work to protect these incredible species. Without them, our lives and life in the ocean will be a much poorer place. Register Login. Email Password Lost your password? So what can you do? More About Climate Change The science everyone needs to know about
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