How Fish Feed: For One Thing, They Suck It Up

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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Video Sidebar: Fish Bottomfeeding Strategies

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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Sharksuckers: Not Just for Sharks! And They Don’t Suck

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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How Fish Breathe: Ram Ventilation, Buccal Pumping

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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The Shrimp-Goby Connection: An Ocean Odd Couple

GOOGLE THIS FISH, THE SPOTTED PRAWN GOBY, and most of the posts you’ll find are for the aquarium trade. Amblyeleotris guttata appears to be a popular fish for home saltwater aquariums. Www.fishbase.org carries a listing for it, but it’s largely related to it colors, size and distribution (which is the Western Pacific from the Philippines down to the Great Barrier Reef at Australia. This photo was taken on the GBR). IT’S A SHRIMPGOBY    All

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The Lionfish Enigma: Atlantic Threat But Not Pacific

LIONFISHES HAVE BEEN AROUND IN THE INDO/PACIFIC FOR EONS, yet almost all talk about them focuses on their presence in the Atlantic and Caribbean. Google “lionfish” and you’ll find a zillion articles on them as an invasive threat in the Atlantic basin for each one about them in their native habitat. Okay. That’s a bit of hyperbole, but the idea is good. There’s an enormous disparity in Atlantic and Pacific lionfish articles. Almost all of

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Osteichthyes vs. Chondrichthyes, Bony vs. Cartilaginous

The terms Osteichthyes and Chondrichthyes may seem a trifle wonkish, as opposed to street talk like “bony fish,” “sharks” and “rays,” but you will encounter them from time to time and should at least be aware of them. •   Osteichthyes (os-tee-ik’-thee-eez, from the Greek for “bone” and “fish”) is the taxonomic class of bony fishes, those with hard, rigid skeletons based on calcium, phosphate and other minerals, smooth scales, covered gills and flexible fins. With

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Trumpetfish: Sneaky, Relentless Predators on the Reef

THINK ABOUT THE MOST RELENTLESS HUNTERS ON THE REEF and you probably envision menacing sharks, barracudas and moray eels. But those are mere grandstanders in the predation game. High on the list of sneaky relentless predators would have to be a species of fishes that Caribbean divers encounter so frequently – and that appear so benign – that they’re likely to take them for granted and ignore them. After all, the ever-present trumpetfish (Aulostomus maculatus)

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Balloonfish & Porcupinefish: Big Eyes, Mona Lisa Smile

WHAT’S THE DIFFERENCE BETWEEN BALLOONFISH AND PORCUPINEFISH?  They’re both unobtrusive, usually little guys with an ability to inflate into spiny basketball-shapes when disturbed. It’s a defensive response to threats. And, divers are often confused as to which is which. First of all, when you see picture of them, they’re often inflated like stuffed pincushions. In fact, like this…. But the truth is that recreational divers who are minding their manners are unlikely to see them

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Hamlet Fishes: Chasing the Hamlet Grand Slam

WHO KNEW THAT SPOTTING LITTLE GUYS LIKE BUTTER AND BARRED HAMLET FISHES could be challenging? I’ve thought of them as fairly bland little fishes of modest interest. I’m aware of occasionally seeing vivid blue indigo hamlets (Hypoplectus indigo) in Bonaire and Belize but not the other dozen or so species to be found around the tropical Atlantic/Caribbean. Which sounds fishy considering that Humann and DeLoache’s Reef Fish Identification says barred hamlets (Hypoplectus puella) constitute the most

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