About 76% of global coral species are found in the Coral Triangle—a region spanning the waters of Indonesia, Malaysia, Papua New Guinea, the Philippines, the Solomon Islands, and Timor-Leste.

Over 1 million fish, marine mammals, and invertebrate species depend on coral reefs for habitats, camouflage, and food.

The National Oceanographic and Atmospheric Administration estimates that US commercial and recreational fisheries valued at $200M depend on coral reefs, which provide up to $1.8B in flood protection by absorbing 97% of wave energy.

The first coral reefs formed hundreds of millions of years ago from the carbonate skeletons deposited by hard corals.

Explore a map of coral reefs around the world and the extent of coral bleaching.

The world's largest coral, as seen from space

The world’s largest individual coral colony—measuring over 100 feet wide and 100 feet long—was discovered in the Solomon Islands. This coral is so large it can be seen from space, and is estimated to be between 300 and 500 years old. The coral's size and health provide hope amidst a global coral bleaching crisis, wherein three-quarters of coral reefs have experienced significant bleaching in recent decades. See the photos from space and learn more here.

Overview: All about coral reefs

Coral reefs aren’t just vibrant underwater landscapes; they are also some of the most biologically diverse ecosystems on Earth. The National Oceanic and Atmospheric Administration (NOAA) offers a comprehensive guide that explores coral reefs in...

From 2023 to 2025, coral reefs experienced their fourth global bleaching event and the largest such event through 2025.

Explore the history, structure, and species of Australia's Great Barrier Reef with this interactive journey narrated by Sir David Attenborough.

The three types of coral reefs—fringing, barrier, and atoll—are categorized by where they form.

Watch a diving expedition through the world's longest coral colony, which spans more than a football field and whose exact location is kept secret for its protection.

The CCZ is believed to harbor trillions of dollars of valuable minerals and thousands of undiscovered species

Located between Hawaii and Mexico and spanning an area larger than the European Union, the Clarion-Clipperton Zone is the world's region with the most contracts awarded to groups seeking to extract valuable metals by collecting polymetallic nodules. Conservative estimates suggest that 21.1 billion tons of polymetallic nodules exist in this abyssal plain, but about 90% of the species in the area are unknown to scientists.

Coral reefs get their colors from zooxanthellae—microorganisms that line corals' digestive tracts and provide them with sugars in exchange for a home within this protective tissue.

Scientists explore innovative solutions to protect coral reefs

As coral reefs are under increasing stress due to climate change, pollution, and other factors, scientists are employing creative solutions to save these crucial marine ecosystems. This National Geographic article explores the various scientific...

Can coral live in cold water?

Dive deep beyond the sunlit coral reefs, and you'll discover a world of deep-sea corals. This article from the National Oceanic and Atmospheric Administration (NOAA) explores the ecosystems of deep-sea corals found way below the water's surface....

Artificial coral reefs have been 3D printed from nontoxic, biodegradable terracotta clay, which coral polyps have used as a foundation for rebuilding marine ecosystems.

Mangrove forests can store up to four times as much carbon as other forests and protect inland areas through complex root systems that absorb wave energy and hold mud and soil in place.

View a collection of glass sculptures of corals threatened by fishing and deep-sea mining.

Coral polyps reproduce via broadcast spawning, where entire reefs simultaneously release reproductive cells for about one hour, once a year.

Synthetic pheromones may protect coral reefs by attracting their predators

Researchers in Australia and Japan have developed these nontoxic chemicals to attract crown-of-thorns starfish, which consume corals that make up the Great Barrier Reef. As of 2026, synthetic pheromones have been shown to be effective in lab trials, and future field trials will attempt to lure starfish into areas for mass removal.

Fungi have been used to restore island habitats in the central Pacific

After removing 1.5 million invasive coconut palm trees and eradicating the black rats that fed on them, as well as seabirds and crabs, conservationists working with the US Fish and Wildlife Service identified areas where fungi could be transplanted to provide nutrients to native trees. These trees serve as nesting sites for seabirds whose guano nourishes coral reefs.

A Tiger economy typically describes a booming Southeast Asian country

The term “tiger economy” has been used over the last several decades to describe a developing country experiencing rapid economic growth, often due to developing export-oriented industries and/or financial markets. The term was originally applied to Southeast Asian economies, including South Korea’s, and has since been used to describe Ireland, the Baltics, and Dubai.

The Ring of Fire is the most geologically active zone on Earth

Spanning 40,000 kilometers as it circles the Pacific Ocean, the region experienced about 90% of the world’s earthquakes and contains over 70% of its active volcanoes. The horseshoe-shaped belt features convergent, divergent, and transform plate boundaries.

Watch a time-lapse of staghorn coral polyps—a type of hard coral—over several weeks in an aquarium, slowly forming the foundational component of a coral reef.

Turning some invasive species into cash crops has helped control their spread

In Mexico, some companies are transforming sargassum seaweed blooms into paper, bricks, and shoes, while in Cambodia, water hyacinths are dried and woven into baskets, rugs, and other crafts. Lionfish and green crabs have been hunted for culinary dishes, with the latter also being used to make crab whiskey in New England.

38 thought-provoking facts about the ocean

Coral produces its own sunscreen, tsunamis move at 500 miles per hour, one of the loudest sounds ever recorded came from an ice quake, and other interesting facts collected from sources such as National Geographic and NASA.

California is one of the world’s 35 biodiversity hotspots

The state comprises the hotspot known as the California Floristic Province, where roughly 3,000 species of vascular plants grow—roughly three-fifths of which are found nowhere else in the world (also known as endemic).

Invasive species are the third biggest threat to Earth's biodiversity

According to the World Wildlife Fund's Living Planet Report 2020, changes in land and sea use account for about half of all recorded threats to the diversity of the planet's species. Species overexploitation is the second-largest proportional threat at 24%, while invasive species make up 13%.

One-third of the world’s food supply relies on pollinators

By supporting crop production and farmland ecosystems, these animals contribute over $200B to the global economy. A 3% to 5% decrease in this production may result in as many as 427,000 deaths due to nutritional deficiencies.

View a breakdown of the identified species on Earth, led by about one million insect species, while mammals such as humans make up one of the smallest groups.

Underwater volcanoes significantly contributes to marine extinctions during the Triassic period

An analysis of ocean basins in the Tibetan Plateau helped identify three major periods of volcanism—250-248, 233-231, and 210-208 million years ago—which released significant amounts of greenhouse gases, altering ocean chemistry. The low-oxygen conditions may help explain half of Earth's Triassic extinctions.

Explaining why animals don't cross this invisible line in Indonesia

Although the distance separating the two regions is small, East and West Indonesia have starkly different species, puzzling scientists for decades. Biogeographers use the theory of plate tectonics to explain the phenomenon, arguing the two regions...

Many religions have core majorities in certain countries

Though most religions have members across the world, they also have major concentrated populations in specific nations. For example, 95% of Hindus live in India, while 85% of the world's Jews live in Israel and the US.

Why 75% of ocean animals glow

About 75% of ocean creatures can make their own light. It's called bioluminescence—and it all comes down to a special chemical reaction happening inside their bodies.

Nearly half the oxygen we breathe comes from photosynthetic plankton, not plants

Although the Amazon Rainforest is considered the "lungs of the Earth," it only produces 20% of the planet's oxygen, while phytoplankton, or microalgae, generate more than twice as much, despite making up less than 1% of the total mass of photosynthetic organisms on the planet. Through photosynthesis, microalgae also absorb up to 40% of global carbon emissions.

These animals are only found in the Amazon rainforest.

The mighty Amazon River and its surrounding rainforest is home to millions of different species of animals, with new ones being discovered regularly.

As of 2025, the world's largest tropical cyclone spanned half the continental US

Typhoon Tip traveled across the western Pacific Ocean in 1979, achieving winds of 300 kilometers per hour. Though it weakened significantly before making landfall in Japan, its rainfall produced over 600 mudslides and killed 42 people.

The love lives of pygmy seahorses

Inch-long pygmy seahorses live fascinating lives in the Coral Triangle of Southeast Asia, where the tiny sea creatures thrive. They are one of the few species in the world where the male carries its progeny to term, in this case, after receiving an egg from the female, who keeps busy checking in on her two male mates, one of whom is always pregnant. Dive into the marine romance in this fascinating essay.

A map of global drug trafficking

The worldwide illegal drug trade continues to flourish. Accounting for almost 1% of the world’s financial revenue, the cocaine trade alone boasts an annual turnover of an estimated $85 billion. This infographic, from Around the World: An Atlas for...

A Florida nuclear power plant canal system hosts the highest density of crocodiles in North America

Biologists have become regular fixtures at Turkey Point Nuclear Plant, where crocodiles found refuge after Florida's population boom pushed them out of coves and mangrove swamps. Teams working on the plant have done their part to modify the land and help the species thrive.

Decommissioned oil rigs have been repurposed into artificial reefs that serve as nursery habitats for fish, corals, sponges, and other invertebrates in the decades since their installation.

Asia-Pacific's share of global venture capital investment has jumped from 3% to 28% in 20 years

China has driven much of that growth due to its manufacturing power and tech sector. This graphic shows how the share of total venture capital deal value changed around the world between 1997 and 2023.

Neglected tropical diseases affect more people than the population of Europe

This group of conditions, which includes hookworm, sickens roughly one in seven people on the planet—a tally which dwarfs Europe's population of roughly 450 million. International cooperation and donations are helping to control some of these illnesses, which can be caused by parasites, viruses, and bacteria. They're all treatable or preventable, but primarily occur among poor, isolated communities that may not receive adequate care.

See what regions report new leprosy cases

This graphic shows the burden of leprosy by region for 2023, based on data provided from the World Health Organization, which collates this information. Southeast Asia leads in the number of cases by region. (Some readers may experience a paywall.)

The 500 subsea cables that run the internet

Subsea cables carry the majority of data sent across the globe on the internet. An estimated 552 such cables—with more in development—lay on the ocean floor, their thickness similar to a garden hose, made up of optic fibers covered in copper.

How Guam became an island of snakes and spiders

The US territory of Guam has 40 times the number of spiders of nearby islands, and a voracious collection of snakes which has nearly emptied it of any native birds. Researchers took it upon themselves to count the species and determine what turned the island into such a haunt of arachnids and serpents, where walking into the woods can mean navigating endless layers of spider webs. Find out more here.

Jakarta surpassed Tokyo as the world's largest city in 2025

Asia is the epicenter of global urban population, hosting most of the world's ten largest cities by population. The top three are Jakarta, Indonesia, Dhaka, Bangladesh, and Tokyo, Japan.

Visit these 'blue zones,' where people live the longest

Blue zones, a term coined in 2004 by National Geographic Fellow Dan Buettner, are regions in the world where people live the longest and healthiest lives. Researchers have identified a few key aspects defining the culture of these areas—physical activity, diet, purpose-driven lives, and more. Explore the top five blue zones from across the world here.

Explore an interactive map of global water gaps, caused by demand surpassing replenishment

Humans extract 4,000 cubic kilometers of water from natural systems annually—eight times more than a century ago—creating regions where freshwater demand surpasses available reserves. The depletion of shallow aquifers has driven tapping into deeper, nonrenewable ones, threatening ecosystem sustainability.

Less than 0.1% of the approximately 20,000 known bee species make honey

The majority of honeybee species originate in South and Southeast Asia, with the largest—Apis laboriosa—found almost exclusively in the Himalayas. The smallest is the black dwarf honeybee, Apis andreniformis, which inhabits tropical and subtropical regions of the continent.

Explore the 2025 Ocean Photographer of the Year winners and finalists

The Ocean Photographer of the Year celebrates and advocates for the ocean and its creatures. From tiny 3mm amphipods to hunting orcas, see a collection of images highlighting the beauty of our blue planet.