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Ocean life

Incredible diversity exists in the ocean, from microscopic organisms to the largest animals on Earth.

whale shark
WHOI Senior scientist and Director of the Ocean Life Institute Simon Thorrold was tagging whale sharks in the Red Sea with the support of King Abdullah University of Science and Technology (KAUST) and reporting back via Facebook. On April 1, Thorrold sent this photo and wrote: "One of the sharks from yesterday was considerably further offshore than we normally see them and in some beautiful blue water that made for a good photo op. This shark also got a GPS tag so we will wait anxiously to see if we hear from the tag in the next few days." (Photo by Simon Thorrold, Woods Hole Oceanographic Institution)

Every drop of ocean water holds living things.  

Across Earth's history, the ocean has nurtured nearly every form of life that has ever existed. Immerse yourself in the diverse ecosystems around coral reefs, the surprising homes of marine microbes, the migrations of giant marine mammals, and the clues embedded in Environmental DNA.  

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Light micrograph of the benthic foraminifer Nonionella stella, which thrives in anoxic sulfidic sediments far below the euphotic zone. Individuals are ~225 microns in diameter. (Image credit: J.M. Bernhard © Woods Hole Oceanographic Institution)

Benthic life

Benthic animals live on the sea floor and are typically invertebrates, such as sea anemones, sponges, corals, sea stars, sea urchins, worms, mussels, crabs, and more.

evidence of coral bleaching

Coral stressors

Stressors can affect organisms living on the reef or they can affect the corals, themselves. When corals die, other organisms must relocate or struggle to survive.

Corals

Many people think of coral as hard, rock-like formations that attract abundant, diverse marine life. In fact, corals are tiny marine animals called polyps that live together in colonies.

emperor penguin

Emperor penguins

The emperor penguin is the largest living penguin species standing around 115 centimeters tall. Once they have found a partner, they work together to keep their young fed and safe.

Coastal ecosystems

The narrow region where land and ocean meet includes salt marshes, mangroves, wetlands, estuaries, reefs, and bays often linked in a network of physical, chemical, and biological interchanges.

Tubeworms are part of a fascinating deep-sea ecosystem that thrives around hydrothermal vents, where life is powered by chemicals instead of sunlight. Courtesy of Jason Sylvan, Texas A&M Univ./NSF/HOV Alvin/2019/© Woods Hole Oceanographic Institution

Ecosystems

Ocean ecosystems are found in polar regions, coastal waters, coral reefs, hydrothermal vents, the abyssal plain, and at the bottom of the sea.

eDNA

Environmental DNA (eDNA)

Environmental DNA (eDNA) is essentially DNA collected from the environment. As animals swim through the ocean, they're constantly releasing DNA as they shed skin or scales into the water column.

Phytoplankton

Phytoplankton are primary producers of the ocean—the organisms that form the base of the food chain. WHOI explores the microscopic, single-celled organisms.

Great barrier reef queensland

Reef ecosystems

A healthy reef protects coastlines from wave damage, plays a critical role in providing food, boosts the economy, and provides materials for pharmaceuticals.

Ctenophore

Jellyfish & other zooplankton

These animals live all or part of their life suspended and drifting in fresh or salt water, rarely come in contact with hard surfaces.

tubeworms and crabs

Life at vents & seeps

Hydrothermal vents and cold seeps are places where chemical-rich fluids emanate from the seafloor, often providing the energy to sustain lush communities of life in some very harsh environments.

Polar life

By human standards, they are extreme environments. Yet life not only persists in the poles...it thrives.

Reef fish

Fish that inhabit a coral reef play essential roles in the reef ecosystem, and reefs without fish struggle to recover from bleaching or other events that damage the coral.

seagrass

Seagrass meadows

Seagrass meadows are plants adapted to live a completely submerged life in the salty shallows.

Marine mammals

Marine mammals are warm-blooded vertebrates that bear live young and nourish them with milk as land mammals do, but that spend most or all of their lives in the ocean.

Marine microbes

Microbial life can be found throughout the ocean, from rocks and sediments beneath the seafloor, across the vast stretches of open water, to intertidal and surf zones.

diatoms350_380454.jpg

Ocean plants

Ocean plants are critical to marine life—they are an important food source, they provide oxygen to surrounding marine life, and they supply refuge and nursery grounds.

Aerial view of a North Atlantic right whale swimming near the surface, pale callosities visible on its head.

Right whales

The North Atlantic right whale is one of the ocean's most endangered large animals, with only a few hundred left. Slow-moving and often near the surface, these baleen whales are especially vulnerable to ship strikes and entanglement in fishing gear.

A pair of wandering albatrosses with a juvenile ready to fly. (Photo by Henri Weimerskirch)

Seabirds

Seabirds have adapted to life in an ocean environment. There are many species of seabirds, and they vary greatly in behavior and physiology

whale shark

Sharks & other fish

Fish are vital to healthy ecosystems and economies, serving as predators and prey while maintaining balanced food webs and protecting habitats like coral reefs and mangroves.

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