Fish

With over 32,000 described fish species, the varieties are endless. Most bony fishes are cold-blooded, covered in scales and breathe using gills—but there are exceptions to all of these rules.  

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X-ray image of a winghead shark

DIVE DEEPER

X-Rays of Fish Reveal Diversity

Scientists in the Division of Fishes at the Smithsonian's National Museum of Natural History use X-ray imaging to study the...
A Pontoh pygmy seahorse

10 Things You Never Knew About Seahorses

By Lindsay Aylesworth, Project Seahorse The day I stepped into my wetsuit, donned my mask, and embarked on my first scuba dive was the day I decided to be a marine biologist. Little did...
A polar bear and its cub in Arctic National Wildlife Refuge, Alaska.

Celebrating Marine Moms

The ocean is home to many moms of all shapes and sizes: from charismatic polar bears and dolphins to small fishes and shrimps and more. Learn about some of the diverse parenting habits of...

Helpful Herbivores

Convict surgeonfish are the roaming sheep of the reef but, instead of noshing on grass, they feed on algae. Credit: Michael Webster When snorkeling in the Kahekili Herbivore Fisheries Management Area (KHFMA) in West...
A photo of a squid using bioluminescence to hide in the deep sea.

Bioluminescence

You may have seen the sparkle of fireflies on a summer’s night. The fireflies produce light through a chemical reaction in their glowing abdomens, a process known as bioluminescence. But did you know that...

Where the Shark and the Snapper Roam

Grey reef sharks are among the most versatile and tough predators on a Pacific coral reef, but they are also among the most vulnerable species, as they are threatened by wasteful fishing practices like...
An albatross soars over the ocean.

Is It Love? Why Some Ocean Animals (Sort Of) Mate For Life

We often hear stories of animal love— tales of rare monogamy in the animal kingdom where life-long love is implied. But there is a distinction between romantic love and an efficient mating system. Here’s...
Tiny jellies in a petri dish.

Fishing for Plastic: Science in the Great Pacific Garbage Patch

By now, you have probably heard of The Great Pacific Garbage Patch . The name conjures the image of a floating island made of familiar plastic trash such as soda bottles and plastic bags,...

Why the Littlest Fish Matter a Whole Lot

A tornado of sardines swirls around diver and photographer Erwin Poliakoff in the Philippines. Credit: Erwin Poliakoff Top predators along the California coast are having a rough year. Recently starving sea lions have showed...
A school of akule (Hawaiian for bigeye scad) explode into a camera's frame.

Following the Akule

Credit: Wayne Levin While swimming off of the big island of Hawaii in Kealakekua Bay, I saw what first appeared to me as a coral head. As I approached I saw movement within the...

Lionfish on the Loose

The majestic and highly predatory red lionfish ( Pterois volitans ) , native to the Indo-Pacific, is invading Atlantic waters. The lionfish is a popular home aquarium species, and some were most likely dumped...

Chasing a Basking Shark

"Ocean sunfish" by Mark Harris Credit: Mark Harris It was a hot and sunny day, with barely a whiff of breeze. I boarded a boat in Oban, on the coast of Scotland, and headed...

Bite Size: Bull Shark Predation of Tarpon

Follow a journey with satellite tags placed on bull sharks and tarpon. Both of these large predatory fish are found in coastal in-shore ecosystems and the two species have similar diets. If given the...

The Secret Life of Plankton

Imagine if a fish at the market could tell you where it came from; what would it say? "I came from a world of drifters," says one fish in this video. The world of...

Meet the Tiny Bacteria That Give Anglerfishes Their Spooky Glow

Descend two hundred meters (about 656 feet) below the surface and the ocean is reduced to total darkness. Creatures that live beyond the Twilight Zone spend their lives almost entirely in a near-limitless black...
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From Larvae to Adults – Finding Impacts of an Oil Spill on Mahi Mahi

A school of mahi mahi (or dolphinfish). Credit: © Tony Ludovico By Emily Frost For a month during the summer of 2016, Lela Schlenker spent several hours in the dead of night watching mahi...
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When Life Gives You Lionfish…

Jeweler Palovi Baezar with her first set of lionfish earrings, which she made in the summer of 2013. Credit: Phil Karp By Kalila Morsink It was the summer of 2013, and Phil Karp was...

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