• U.S. Marine Protected Areas

    U.S. Marine Protected Areas

    The United States' nearly 1,800 marine protected areas contain some of the country's most spectacular reefs, archaeological sites, and diving sites.

  • Corals


    Coral reefs are some of Earth’s richest and most diverse ecosystems. Tiny animals build these largest biological structures on the planet—some of which can be seen from space.

  • Strange-Looking Sea Creatures

    Strange-Looking Sea Creatures

    Among the ocean’s countless species, some stand out for their looks—but not always in a good way. Meet some of the sea’s most unusual-looking animals.

  • Jellyfish


    Jellyfish aren’t fish but invertebrates, animals that lack backbones and even brains. Yet 30,000-odd species do far more than survive—they thrive in ocean waters the world over.

  • Masters of Undersea Camouflage

    Masters of Undersea Camouflage

    Sometimes survival in the deep depends on simply not being seen. Meet the ocean’s masters of camouflage.

  • Translucent Marine Animals

    Translucent Marine Animals

    Sometimes it’s better to remain unseen. These nearly invisible marine animals use their natural translucence to good effect.

  • Squid


    These masters of transformation can change their looks in seconds—to stalk prey, escape enemies, attract mates, stand up to rivals, and more.

  • Marine Microbes

    Marine Microbes

    Microbes make up a staggering 90 percent of the ocean’s total biomass, but many of them remain a mystery to science.

  • Sea Stars

    Sea Stars

    These spiny-skinned echinoderms are found worldwide in a colorful menagerie of shapes and sizes.

  • Sea Anemones

    Sea Anemones

    Many of these colorful ocean “flowers” are actually venomous predators. But anemones also live in symbiotic harmony with several other species.

  • Deep-Sea Creatures

    Deep-Sea Creatures

    Adaptation is the name of the game when you live thousands of feet below the water's surface. See how these deep-sea denizens make the most of their deep, dark home.

  • Nudibranchs


    These wildly colorful mollusks have a message for potential predators: "You'd best look elsewhere for a meal."

  • Colorful Sea Creatures

    Colorful Sea Creatures

    The world’s largest creatures reside in the ocean, and its depths are home to unusual species whose surprising proportions are unknown on land.

  • Colossal Sea Creatures

    Colossal Sea Creatures

    The world’s largest creatures reside in the ocean, and its depths are home to unusual species whose surprising proportions are unknown on land.

  • Rays


    See the stingers, shockers, and other amazing abilities of the flattened fish that have gracefully cruised Earth’s seas for 150 million years.

  • One-of-a-Kind Sea Creatures

    One-of-a-Kind Sea Creatures

    The sea is home to millions of species. Some are unique enough to truly stand out from the crowd.

  • Kelp Gardens

    Kelp Gardens

    See photos of fascinating aquatic life in kelp gardens around the world.

  • Coral Reefs

    Coral Reefs

    Discover one of the most beautiful—and threatened—habitats on Earth.

  • Ocean Wildlife

    Ocean Wildlife

    Take a dip to discover some of the incredible wildlife that make their home in the ocean, from sea turtles and bearded seals to poisonous jellyfish and starfish.

  • Oceans


    Dive into one of the most magnificent habitats on Earth.

  • Dangerous Sea Creatures

    Dangerous Sea Creatures

    The ocean is full of beautiful creatures—but some of them can be hazardous to your health.

  • Toxic and Stinging Sea Creatures

    Toxic and Stinging Sea Creatures

    The seas are home to some of the planet’s most toxic creatures. Go ahead and take a good look—but don’t touch.

  • Seabirds


    As at home on the water as they are on land, these birds can list swimming, diving, and fishing on their impressive avian resumes.

  • Marine Worms

    Marine Worms

    A marine worm may resemble a feather duster, a leaf, or even a plate of pasta—and these creatures' amazing abilities are as varied as their appearances.

  • Sea Urchins

    Sea Urchins

    Visually arresting, hazardous to swimmers, and—to some cultures—delicious, sea urchins are also revealing new information to the scientists who study them.

  • Electroreceptive Fish

    Electroreceptive Fish

    The electric ray, and other fish, have the biological ability to perceive natural electrical stimuli.

  • Sea Creature Survival Skills

    Sea Creature Survival Skills

    See photos of sea creatures that have unusual defense mechanisms.

  • Marine Species Under Threat

    Marine Species Under Threat

    See photos of marine species under threat, including polar bears and bluefin tuna.

  • Ocean Reefs

    Ocean Reefs

    See photos of both healthy and degraded coral reefs around the world.

  • Oil Spill's Animal Victims

    Oil Spill's Animal Victims

    See photos of the impact the 2010 BP oil spill has had on wildlife in the Gulf of Mexico.

  • Photo Camp-Ocean for Life

    Photo Camp-Ocean for Life

    See photos from the National Geographic Photo Camp-Ocean for Life program.