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A REMOTE island paradise has become a haven for supersized sharks – and the reason has left scientists baffled.
Tiger sharks are growing an average of two feet longer than those on the Great Barrier Reef off Norfolk Island in the South Pacific.
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The beautiful sharks are known for their black stripes and being related to the great white.
They usually measure about nine feet – but the ones that swarm this remote island reach an unbelievable length of 15ft.
But scientists couldn’t work out why supersized sharks were so attracted to the area.
Australia‘s Nortfolk Island is a former penal colony, a settlement used to exile criminals, and has a history of cattle ranching.
As there is no easy way to get rid of dead livestock without poisoning groundwater, ranchers would reportedly bin the remains into the ocean.
At first, experts thought the massive beasts were around to take advantage of the bloody leftovers – but they found something even more baffling.
They looked into the sharks’ diet to see if it was the cow carcasses that were making the gigantic sea creatures stick around.
But they found that only 10 per cent of the sharks’ diet contained cow.
Professor Charlie Huveneers told National Geographic: “That’s a tiny amount compared to what we expected.”
This made it clear the sharks were eating something else.
Research found that 52 per cent of the sharks’ diet was bizarrely seabirds – and scientists were reportedly so shocked they had to double check their data.
The birds are called wedgetail shearwater – and thousands flock to Norfolk Island to nest.
The seabirds reportedly float on water at dusk, making them easy pray for the massive sharks.
Biologist Lauren Meyer explained how the sharks get the birds: “It would be very difficult for the birds to detect a predator coming up from underneath, especially at this time of day.
“Seabird rafting behaviour at dusk is the perfect opportunity for sharks to come up and use their big, flat noses to suction these birds off the surface.”
Tiger Sharks
Tiger sharks are named from the black, vertical stripes that appear mostly on youngsters.
As these sharks develop, their lines fade and practically vanish, National Geographic reports.
Tiger sharks are one of only three species considered extremely dangerous to humans, accounting for nearly all fatal encounters, along with bull sharks and great white sharks.
However, because they have such an undiscerning taste, they are unlikely to swim away after biting a human, like great white sharks regularly do.
Tiger sharks are common in tropical and subtropical waters across the world.
Large ones can reach 20 to 25 feet in length and weigh more than 1,900 pounds.
They are consummate scavengers, with sharp, highly serrated teeth and strong jaws capable of cracking sea turtle and clam shells.
Tiger sharks are frequently collected for their fins, skin, and flesh, and their livers contain a high concentration of vitamin A, which can be processed into vitamin oil.
They have extremely poor repopulation rates and hence may be especially vulnerable to fishing pressure. They are classified as near threatened across their range.
Sophia Emmons, a PhD student explained why seabirds are a great meal for tiger sharks.
She told National Geographic: “With a very good food source, whether it’s primarily from the cattle or from the seabirds, tiger sharks can expend more energy and put more of that into growth.”
Tiger sharks are common in tropical and subtropical waters across the world.
They have extremely poor re-population rates and are classified as near threatened across their range.
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