{"id":36761,"date":"2024-03-22T16:52:10","date_gmt":"2024-03-22T15:52:10","guid":{"rendered":"http:\/\/6c5b8d09-f5d0-464e-9d11-db2fc74799de"},"modified":"2024-03-22T17:35:42","modified_gmt":"2024-03-22T16:35:42","slug":"hammerheads-come-equipped-with-underwater-metal-detectors-and-hold-their-breath-to-dive-to-the-deep","status":"publish","type":"rss_feed","link":"https:\/\/c01.purpledshub.com\/bbcwildlife\/rss_feed\/hammerheads-come-equipped-with-underwater-metal-detectors-and-hold-their-breath-to-dive-to-the-deep\/","title":{"rendered":"Hammerheads come equipped with underwater metal detectors, and hold their breath to dive to the deep"},"content":{"rendered":"

Scalloped hammerheads captivate the imagination of scientists, conservationists, and nature enthusiasts alike. Here\u2019s why <\/p>

By Mike Dilger\n <\/p>

Published: Friday, 22 March 2024 at 15:52 PM<\/p>

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While hammerheads stand out as one of the most recognisable shark species<\/a>, there’s much more to this species than meets the eye.<\/p>

The majestic \u2013 and intriguing \u2013 scalloped hammerhead shark. Credit: Getty<\/em><\/figcaption><\/figure>

What is a scalloped hammerhead shark?<\/h2>

With just over 500 different species of shark classified, and a further two dozen waiting to be formally scientifically named, shark taxonomy is not for the faint-hearted. But there is one group that surely everyone would immediately recognise: the hammerheads.<\/p>

Sporting a wide, flattened head that is uniquely shaped like a double-headed hammer, it\u2019s not hard to see how these sharks got their name. The eyes and nostrils are located at either end of the \u2018hammer\u2019 \u2013 or cephalofoil, as it\u2019s technically called.<\/p>

Why are scalloped hammerhead sharks shaped like that?<\/h2>

Of the nine species of hammerhead, the \u2018scalloped\u2019 can be distinguished by the notches along the leading edge of its cephalofoil, which produce a distinct scalloping effect. The females tend to be larger than the males \u2013 and the species\u2019 bronze-grey back and white underside help camouflage the shark from prey and potential predators, both above and below in the water column.<\/p>

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Scalloped hammerhead sharks are easily recognisable thanks to their distinctively-shaped heads. Credit: Getty<\/em><\/figcaption><\/figure>

The explanation behind the shape of the hammerhead\u2019s head has long been debated. While undoubtedly giving the sharks extra lift, the cephalofoil may also help them make sharper turns in the water. <\/p>

The widely spaced eyes allow for effective stereoscopic vision, while the head\u2019s broad shape also houses a sense organ known as the ampullae of Lorenzini. Packed with electroreceptors and operating like an underwater metal detector, it helps the sharks to detect prey hidden on or just under the sea-floor sediment.<\/p>

Hammerheads have 360\u00ba vision in the vertical plane, able to take in their surroundings both above and below.<\/p>

Another possible function for the hammerhead’s head is to help pin down any slippery prey unearthed from the seabed. Once secured, the shark\u2019s finely serrated teeth then act as knives and forks, allowing the prey to be either swallowed whole or dismembered in bite- sized chunks.<\/p>

How big are scalloped hammerhead sharks?<\/h2>

Born at around 50cm, males mature to about 1.4-1.65 metres, while females reach just over two metres. However, the maximum length for this shark is between 3.7-4.2 metres.<\/p>

Why do hammerheads swim in shoals?<\/h2>

While it can be relatively easily observed at a number of sites, particularly around seamounts (submarine mountains), there are only a few places where it gathers in large numbers. As most apex predators operate either as \u2018lone wolves\u2019 or in small cohorts, this is considered highly unusual behaviour. These groups, or \u2018shivers\u2019, of sharks tend to consist mostly of females, with the males remaining out in deeper waters.<\/p>

At locations such as the Gal\u00e1pagos<\/a>, numbers can reach into the hundreds or even, on occasion, thousands. As the sharks tend to congregate relatively close to the water\u2019s surface, this is one marine spectacle where a mask, fins and snorkel, rather than a full scuba kit, will often suffice.<\/p>

BBC Earth’s short film about scalloped hammerhead sharks<\/h3>

Watch this stunning footage, which delighted the BBC Earth film crew. It takes a closer look at male and female hammerhead shark’s intriguing mating behaviour. <\/p>

That was a good morning in the office<\/p>Shark researcher, Alex Hearn after diving with hammerhead sharks for BBC Earth<\/cite><\/blockquote>

No time to see it all? Don’t miss the wonderful highlight around 1:30 mins in.<\/p>