Shark breakthrough: 450 million-year-old great white mystery unravelled in Cape Cod probe

The great white is a species of large mackerel shark renowned for its daunting size, with some growing up to 20 feet in length – but most are much smaller, with females averaging around 15 to 16 feet and males tending to be between 11 and 13 feet. The beasts of the ocean were made popular by Steven Spielberg’s ‘Jaws’ thriller, in which they were depicted as ferocious man-eaters, but humans are not their preferred prey, in spite of a large number of reported attacks. Despite this, it would be reasonable to assume jumping in the water to go face-to-face with a great white, armed with nothing more than a towel is an absurd proposal.

But that is exactly what scientists from OCEARCH have been doing for years.

Greg Skomal, chief fisheries scientist revealed: “We don’t know much about the great white shark’s natural history, its ecology from day-to-day, how it lives and interacts with its environment.

“But when you come onto this vessel and you have a live animal in front of you that you can study, it just opens new doors – you can get a more robust assessment in a very short period of time.”

Just a few kilometres from where Spielberg filmed his 1975 Hollywood blockbuster, the OCEARCH team has been on the lookout for sharks.

Cruising along the Cape Cod coastline in Massachusetts, they lure the predators with mashed-up herring, tuna, and a dummy in the shape of a seal.

A towel is one of the tools used to placate the fearsome creature while a team of researchers carry out important investigations into its mysterious living habits.

The group of scientists place a dark cloth over the shark’s eyes to calm it down long enough to attach an electronic tag, take blood samples and even conduct an ultrasound.

Captain Brett McBride told CNN in 2013: “As soon as we bring them on the platform the first thing I do is cover their eyes with a dark, wet towel and that usually calms them right down. 

“Then I will take two hoses with a lot of volume of water and make sure that it’s nice, clean seawater with bubbles in it that will cascade down each side of the gills.”

Scientists first started tagging the mysterious creature in the Sixties, often using a harpoon to attach a GPS device. 

Around 500 great whites have since been tagged around the world, revealing fascinating glimpses into their movements through the world’s oceans.  

One of the greatest distances ever recorded was that of a great white travelling from South Africa to Australia in 99 days, covering more than 11,100km. 

Expedition leader Chris Fischer added: “What we have found is that male (great white) sharks are all living along the beach all the time – they have very little off-shore life. 

“But the females go way out over Madagascar, and even out into the middle of the Indian Ocean, and they hang around out there for months and months.  

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“What are they doing out there? Are they gestating their babies? Are they feeding?

“Shark populations worldwide are under threat – sharks are being slaughtered at an unsustainable rate, many for a bowl of soup. 

“This unsustainable harvest rate is driven by the demand for shark fins, meat and other products, and puts not only sharks at risk, but also the entire balance of the ocean. 

“This project is about solving the annual movements of the great white shark around the north Atlantic – it’s a 450 million-year-old mystery and today everyone gets to watch it unfold in real-time.”

Since 2013, experts have become increasingly concerned that great white sharks could become extinct thanks to the same research.

They say the Atlantic Ocean would experience an environmental collapse as a result.

California’s underwater kelp forests have been in demise following an explosion in urchins that eat the kelp, and that is due to a decline in sea otters that eat the urchins.

This is threatening the natural food chain of the area, which could completely collapse if great whites have no source of prey.

Bryan Franks, a Jacksonville University doctoral professor said in 2019: “I can say with certainty you would lose stability, but there are so many factors involved it’s difficult to predict.

“Their prey would go up, then that third-level species would be depleted, but it’s difficult to model.  

“The classic example is the otters, the urchins and the kelp.”

Using DNA and tracking information, OCEARCH scientists hope to map the entire global family tree one day.

For now, they still don’t know how many great white sharks there are in the northwest Atlantic, but guess it is around 1,000.

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