FAR FROM BEING FREE-RANGING LONERS, MANTA RAYS BOND WITH EACH OTHER in relationships that often last for extended periods, according to a five-year study of manta ray socializing in Indonesia. Some mantas form loosely connected groups to hang out with. Not surprisingly, like their human counterparts, female mantas form much tighter friendships with other females than males do among themselves. The males? Well, the boys’ groups were looser and they tend to cruise more. MANTA
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POCKET SHARKS ARE SO SINGULAR THAT AS FAR AS THE WORLD KNOWS there are only two known species – and only one specimen of each. The first resides in a museum in Russia. The second, found in the Gulf of Mexico and just identified, has been given a scientific name but it’s probably going to be known as the American pocket shark. If having one specimen each of two species makes them the world’s rarest
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SHARKS ARE KIND OF NOTORIOUS FOR HAVING TEETH – it is, after, all the principal reason we fear them. But they’re also famous for losing them. And some of us diving human beings are famous for hunting shark teeth. In fact, sharks drop teeth continuously. Inside their powerful jaws, they have multiple rows of choppers. When one falls out, one behind it moves forward to take its place, as if on a conveyor belt. Over
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DO SHARKS HAVE TO SWIM CONSTANTLY IN ORDER TO BREATHE? The answer is yes – for the relatively small number of shark species that excite us the most, like great whites and hammerheads. But it’s not the case with most of the 400-plus species of sharks in the oceans, like the familiar nurse shark and lesser-known species like bullhead, angel and carpet sharks. WATER, OXYGEN & GILLS Like all fish, sharks breathe by extracting oxygen
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DIVING WITH MANTA RAYS WAS SORT OF A DISTANT FANTASY. I just wanted to see them. The giant Atlantic mantas I had seen in the past were fast-moving and, mouths agape, totally focused on sweeping up the plankton they make their livings on. Suddenly here, there, gone. Spending extended time in close-up choreography with one of these gentle giants was not in my vision. Until it was. The dive was at Flower Garden Banks National
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MANTA RAYS ARE FOUND IN OCEANS WORLDWIDE, BUT MANTA RAY JUVENILES ARE RARELY SEEN. Except, it develops, in the newly recognized manta ray nursery in the Gulf of Mexico’s Flower Garden Banks National Marine Sanctuary. When visiting manta specialist Josh Stewart told Flower Gardens staff he had spotted only the second juvenile he had ever seen, their response was: they see them all the time. Apparently, they assumed the smaller mantas were a different species
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1) THERE ARE TWO SPECIES OF MANTA RAYS – OCEAN MANTAS (MANTA BIROSTRIS) AND REEF MANTAS (MANTA ALFREDI). M. birostris is also sometimes known by the names giant ocean manta and Atlantic giant manta. Mantas are the largest members of the ray family and among the largest fishes in the sea. 2) Oceanic mantas are found worldwide, often reported as swimming great distances across oceans. They generally prefer tropical and subtropical waters. 3) Reef mantas are
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HOW SHARKS SMELL BLOOD IS FAR MORE INTERESTING than their mythical ability to detect the scent of “a drop of blood miles away.” Scientists disproved that legend long ago, although you may still find it in cheesy movies and on shark-week type reality shows. Sharks do have an amazing sense of smell, but their long-range detection capabilities are limited to several hundred yards rather than miles, many authoritative sources suggest. And one study suggests that
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APPARENTLY IT TAKES TIME TO GROW TO BE THE WORLD’S BIGGEST FISH. A new study of whale shark size and age has indicated that gargantuan fishes can live to the ripe old age of 130 years. Marine biologists at the U.K.-based Maldives Whale Shark Research Programme and Florida’s Nova Southeastern University analyzed a decade’s worth of repetitive, non-invasive underwater measurements of whale sharks in the Maldives to understand whale shark age and growth details. Previous
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HERE’S A REMARKABLE PHOTO OF A SHARK PUP HATCHING, published in the terrific science magazine bioGraphic. It’s a small spotted catshark (Scyliorhinus canicula), caught just after its emergence from its egg casing. That’s its name – small spotted catshark – but the little shark has other common names, including lesser spotted dogfish. Recreational diver are not so likely to see one. S. canicula is a bottom-dweller at depths from 30 to 300 feet/10 to 300
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