Seahorses are at once weird and wonderful, exotic and underwhelming and unique among bony fishes. Underneath their obvious horsey-head charm, seahorse anatomy is really, really different from other fishes. THE MOST OBVIOUS THING ABOUT SEAHORSES IS THEIR BODY DESIGN – an upright torso connecting a horse-shaped head and a monkey-like tail. They’re bony fishes, but pretty much the only bony fish that swims upright. When they swim. If searching for them carries an air of
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As the world ponders ways to capture carbon and combat climate change, think about the idea of whales and carbon storage. During their long lifetimes, great whales takes gargantually more carbon dioxide out of the atmosphere than whole forests of trees – and keep it there. A new study underscores our cetacean cousins’ importance to our planet beyond just oceanic diversity. GREAT WHALES SWIMMING IN THE OCEANS DON’T SPRING TO MIND AS A SOLUTION TO
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If your idea of how fish feed on the reef is ferocious hunters swooping in to grab other fishy prey, you’re very unlikely to see that on most dives. But the 28,000 species of bony fishes in the world’s oceans make their livings in a myriad of ways – and they’re doing it all around you. IF YOU’RE SURPRISED AT HOW LITTLE FISH-ON-FISH FEEDING ACTION YOU ACTUALLY SEE WHILE YOU’RE UNDERWATER, a major reason is
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This is a video sidebar to a longer feature on “How Fish Feed.” Two minutes in length, it shows four types of fish bottomfeeding techniques to find and capture small crustaceans, mollusks and other invertebrates buried in the sand flats surrounding reefs. WHEN YOU’RE TALKING ABOUT LOAN SHARKS AND SHADY LAWYERS, “bottom-feeding” is a disparaging term. But for lots of fish and other reef denizens, it’s a productive way of life. We may see a
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ON THE REEF, OYSTERS, SCALLOPS, CLAMS AND MUSSELS ARE PRETTY MUCH THE INACTION FIGURES. Mostly, they just sit there. If you come close, they clam up, so to speak, until you go away. Yet, environmentally, economically and, yes, culinarily, they’re big players in the oceans and in our kitchens. Spoiler alert: The bivalve mollusks you’ll see on the reef are unlikely to be the ones seafood lovers salivate over. But, they’re likely to be more
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With grape-sized, sac-like membranes, bubble corals look soft, squishy and egg-like from the outside. But underneath, Plerogyra sinuosa and its like are hard, stony corals. Although they’re popular with home aquarium enthusiasts, it’s somewhat of a find to spot bubble coral on the reef. WHEN YOU COME ACROSS CLUSTERS OF BUBBLE CORAL, at first glance you might take them for large fish eggs, or perhaps errant egg clutches of some animal, say a cephalopod. Once
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More properly known as remoras, the “sharksuckers” that famously hitch rides on sharks also stick themselves to tunas, manta rays and other large fishes, turtles, whales, boats and anything else that might move. Including, occasionally, divers. SHARKSUCKERS – REMORAS – USE LARGE SUCTION PADS on the tops of their heads to stick to their hosts, relying on those sharks, rays or whatever to do the heavy work of actually moving. The suction pads are transformed
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FISH GOTTA SWIM…THEY ALSO GOTTA BREATHE. Or, more properly, they need to continuously restock their blood supply with oxygen from the surrounding water column to maintain the functions of living. Key to how fish breathe is the constant streaming of water past thin, permeable membranes in their gills that enable the diffusion of oxygen from the water into the blood stream. Fish maintain that flow of water by either of two methods – ram ventilation
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THREE THINGS TO KNOW ABOUT MANGROVE FORESTS: 1) They aren’t swamps. They grow in shallow ocean waters along tropical coasts, surviving tidal fluctuations and thriving on the edge between land and sea. 2) Mangrove trees generate the freshwater they need for survival by using a variety of mechanisms to filter the salt out of the ocean water. 3) They’re essential parts of reef systems, key to the reef life. ABOVE AND BELOW Above water,
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THERE ARE TWO KINDS OF DIVERS: THOSE WHO ARE BONKERS ABOUT NUDIBRANCHS and those who ought to be. For those in the second category, here are some nudibranch facts. First, as the name “nudibranch” suggests – it’s from the Greek for “naked gills” – nudibranchs absorb their oxygen from the water through external breathing structures located on their backs. There’s great variation in gill architecture among the many species of nudibranchs, from flamboyant to demure. And
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