Basic information about fishes on the reef

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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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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how do fish sleep

How Fish Sleep: By Resting, Snoozing & Totally Zonking Out

HOW FISH SLEEP DEPENDS ON THE SPECIES. Nocturnal fishes, like cardinalfishes and those closely packed platoons of grunts and gray snappers you see just hanging around by coralheads and pier pilings during day dives, are likely resting rather than actually sleeping. Some species, like parrotfish, clearly sleep at night, although they seem like they can be awakened with minor disturbances (I base this on my own clumsiness around them on night dives). Some, like bluehead

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Hunting Shark Teeth: After the Feeding Frenzy, the Shark Tooth Frenzy

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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Some Sharks Have to Swim to Survive, But Most Don’t

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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Shades of Orange – Clownfish, By the Numbers

1  ALL CLOWNFISHES ARE ANEMONEFISHES, but only two species of anemonefishes get to be called clownfishes, and one of them is the false clownfish (Amphiprion ocellaris). 2   Widely thought of as the archetypal clownfish, the adorable hero of Finding Nemo is actually a false clownfish, with three broad white bands encircling his body. But that’s a design that’s easily animated and he had great marketing reps. 3   The color patterns of true clown anemonefishes (Amphiprion percula) are

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Manta Rays: Gentle Giants Explained

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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 Fish Buoyancy – How Our Finny Friends Stay Neutral (Unless They Don’t)

ONE THING IS CLEAR – FISH HAVE BETTER BUOYANCY THAN YOU.  And, they don’t have to press any buttons. Many bony fishes have built-in versions of the buoyancy-compensators that divers use to control their position in the water versus changing ambient pressures. In these fishes’ case, it’s an internal gas-filled sac called a swim bladder that automatically works to counteract the ambient pressures applied by the waters surrounding it and keep the fish at neutral

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