Benthic & Pelagic Fishes: Defining Oceanic Lifestyles

Describing pelagic fishes is easy: They swim, feed and just hang out in the open ocean, a pretty consistent pattern across many ocean-going species. Describing benthic fishes is something else. They live at the bottom of the ocean but they go about their lives in a bunch of differing ways – above, on and sometimes in the seafloor. Some may engage in all three approaches. IF TOLSTOY HAD WRITTEN ABOUT MARINE LIFE, he might have

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Why Are Flounders Flat? Because it Works.

Flounders are famously fishes that start out with typical-fish body shapes and morph into bottom-dwelling flatfishes that live sideways, with both eyes on the same side. As weird as this sounds, they’re highly successful survivors and predators. But why are flounders flat? And how do they get flat?  FLOUNDERS ARE THE FISHES THAT PABLO PICASSO MIGHT HAVE DREAMED UP – all the parts are there, just arranged differently. And Peacock Flounders obviously would have been

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How Do Flying Fishes “Fly?” Well, Actually, They Glide.

Why do flying fishes fly? To escape predators, to flee from surprises like boat engines next them, perhaps to entertain you during the ride to a dive site. In any event, they earn their names by propelling themselves out of the water and gliding for long distances on broad pectoral fins. Torpedo-shaped and silvery, sometimes with markings in subdued colors, they’re not especially exotic visually. But they’re impressive both underwater and in the air. YOU’RE

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Seahorse Anatomy: Differences Way Beyond “Cute”

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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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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