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
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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A NEWLY IDENTIFIED SPECIES OF SHARK has been named “Genie’s Dogfish” in honor of renowned marine biologist Eugenie Clark, a.k.a. the “Shark Lady.” It may be just coincidence that the news about “Genie’s Dogfish” came out just when the cable networks have resumed telling us that it’s totally unsafe to be in any ocean with any shark. But it’s fitting. Dr. Clark, who died in 2015 at age 92, was a pioneer in shark research
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HAPPY SHARK AWARENESS DAY! I’m not sure who decreed it so but every July 14th is Shark Awareness Day. It’s a time to appreciate our cartilaginous fellow travelers on Planet Earth with a generous supply of actual shark facts. To judge by what we see on cable television, sharks are cold-blooded psychopaths always in a brutal frenzy of hunting man and beast, ready to grab a tasty arm or foot at the first opportunity. LESS
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WHERE’S WALDO? That might be the question this yellow stingray (Urobatis jamaicensis) hopes we’re asking, as it fluffs up sand to try to hide itself. In this case it didn’t work since we watched it approach and then proceed to bury itself – most ineffectively. YELLOW STINGRAY FACTS U. jamaicensis typically measures 12 to 15 inches across, excluding the tail (although the Pittsburgh Zoo & Aquarium, which has yellow stingrays in its collection, says they
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