According to the International Union for Conservation of Nature, as of 2025, there are over 18,000 endangered animal species worldwide, with the share of fish, insects, mollusks, and reptiles increasing since 2007.

Based on a species' population size, distribution, and habitat, it may be designated as a threatened species—vulnerable, endangered, or critically endangered—if it is at high risk of extinction.

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%.

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.

At any given time, there are an estimated 10 quintillion individual insects alive on Earth.

Even in nature reserves, climate change is driving rapid ecological collapse

Studies show a dramatic decline in insect populations, resulting in cascading global biodiversity losses across non-insect species. The balances in tropical ecosystems are the most affected by climate change.

Visual deep dive into the collapse of insects

The most diverse group of organisms on the planet are in trouble, with recent research suggesting insect populations are declining at an unprecedented rate. Explore this visual interactive on the issue from Reuters Graphics.

Native, wild bees are at much greater risk of extinction than honey bees

It is estimated that there are more honey bees, which often compete with native bees for resources, on the planet than at any point in human history. Meanwhile, 40% of invertebrate pollinator species, including wild bees and butterflies, face extinction in the coming decades.

Butterfly populations have declined by 22% from 2000 to 2020

Research suggests that one in every five butterflies is lost due to pesticide use, habitat loss, and climate change. Playing a vital role in pollination, their declining populations threaten plant reproduction and the health of ecosystems.

About one-third of the world's food supply depends on pollinators like bees, butterflies, and bats to transfer pollen between flowers, which use bright colors, scents, and nectar to attract them.

Learn about the plant and animal species in every US county that are federally protected under the US Endangered Species Act with this interactive map.

Desert wildlife: diverse, threatened, and misunderstood

This article sheds light on the surprisingly diverse wildlife that thrive in deserts, while also highlighting the gaps in human understanding of these ecosystems. Deserts are home to one-quarter of terrestrial vertebrate species—three percent of...

Research suggests ants are the most abundant insect on the planet, with an estimated 2.5 million of them for every human on Earth.

Increasing contact between humans and wild animals is driving zoonotic threats

Zoonotic diseases, which spread from animals to humans, present one of the most significant emerging threats worldwide. Scientists have identified around 200 viruses capable of infecting humans, and unfortunately, the number of such diseases are on the rise—at least 60% of all emerging infectious diseases are zoonotic in origin.

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

Feral and free-ranging cats rank among the most harmful invasive species

Transported across the planet by humans, cats can now be found in many environments and are estimated to kill about 2 billion birds each year in the US. Studies suggest cats have contributed to the extinction of at least 63 species worldwide.

There have been five mass extinction events in Earth’s history

Each extinction event has resulted in the loss of at least 70% of Earth’s species at the time of the event, often due to significant changes in global temperatures. The most recent event occurred 66 million years ago and wiped out all non-avian dinosaurs.

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.

A collection of fascinating facts about the planet and its creatures

You may have already heard that cheetahs are the fastest animals on land, but did you know that Savannah elephants are the strongest? This page on the World Wildlife Fund's UK website features a diverse range of articles on mammals, underwater creatures, birds, reptiles, insects, and landscapes. Discover captivating information about Earth and the creatures you share it with.

From 1970 to 2017, invasive species have caused $1.28T in damage globally

The costliest species were the Asian tiger and yellow fever mosquitoes ($149B), which arrived in the US from Asia and sub-Saharan Africa, respectively. The bulk of their damage came from their transmission of diseases such as Zika, chikungunya, and dengue. (Some readers may experience a paywall.)

Some invasive species can provide benefits to ecosystems over time

In the 1990s, round gobies were introduced into the Great Lakes, rapidly spreading and competing with local sculpin and logperch. However, Lake Erie watersnakes, which were on the endangered species list, shifted their diet to be almost entirely made up of the plentiful round gobies, contributing to their loss of endangered status in 2011.

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.

Mosquitoes top the ranking of the world's deadliest animals.

What animals live in the ocean?

The oceans host an incredible diversity of fascinating species. Oceana's Marine Life Encyclopedia beautifully presents facts and photos of ocean animals from Atlantic Cod to Zebra Sharks.

Rapid environmental changes are exacerbating natural extinction processes

Human activities behind climate change, habitat destruction, pollution, and overhunting have resulted in extinction rates up to 1,000 times greater than normal, triggering massive biodiversity loss. This has led scientists to refer to the current geological age as the Anthropocene era, in which humans are the dominant force shaping nature.

Infographic illustrates the diverse and fragile Amazon ecosystems

This infographic helps readers better understand the vast rivers, forests, plants, and animals that call the Amazon rainforest home. Home to the largest collection of plant and animal species in the world, the Amazon rainforest has 16 thousand known...

What's happening to the snowy owl?

This article explores the alarming decline of snowy owls in the Arctic. Once abundant in these northern regions, the snowy owl is now classified as "vulnerable" by the International Union for Conservation of Nature (IUCN). The adult population...

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

West Nile has been detected in at least 2 species of reptiles

Birds remain the main reservoir for the disease, but scientists have detected the virus across a wide range of species, including at least 48 mosquito species, over 320 bird species, more than 25 mammals, and two species of reptiles.

The current state of Amazon rainforest deforestation

Scientists say the Amazon rainforest is approaching between 20%-25% deforestation, a critical tipping point at which the damage is irreversible. Demand for beef and soy are the main drivers.

Benign species can become invasive if introduced into predator-free habitats

Most ecosystems contain organisms that, over many generations, have evolved into a stable balance with one another and their surroundings. In a new environment, a species may no longer be restricted by the limiting factors it is used to, and the native organisms in the area may not adapt quickly enough to the invader to establish a new balance.

Why are coral reefs important?

Coral reefs are vital ecosystems that millions of people and countless species depend on. This two-minute video from London's Natural History Museum looks at the ecological and economic significance of coral reefs, including their biodiversity and...

What is the rarest color in nature?

Plants, animals, or minerals found in nature bear almost every color imaginable. There are two factors that influence what hues you see in the wild: physics and evolution. So, which colors are you least likely to see in the natural world? Victoria Hwang explores one of nature's rarest spectacles.

Humans may be the ultimate invasive species

Originating in East Africa, Homo sapiens migrated across the world beginning about 60,000 years ago and directly harmed countless species by consuming resources and modifying ecosystems to serve our needs. While meeting the definition of an invasive species, some ecologists argue the opposite, claiming that humans have helped preserve numerous species.

How existing technology could prevent nearly 80% of plastic pollution

More than 28 million tons of plastic enters the environment each year, where it harms animals and damages habitats. A study co-authored by researchers at The Pew Charitable Trusts found that this flow can be reduced by nearly 80% in the next 20 years using existing waste management and recycling technology.

Amazon rainforest facts, species, and threats

The World Wildlife Federation presents a brief overview of the Amazon rainforest, covering key facts like location, size, and importance. An overview of threats includes unsustainable resource extraction, climate change, and poorly planned construction projects.

The last Pinta Island tortoise died in 2012 at over 100 years old

Unfortunately, different animal species continue to go extinct. See a list of these recent extinctions, and learn the story of Lonesome George, who died without finding a mate in the Galapagos Islands.

Visualizing the 75 largest underwater animals

With so many fish in the sea, which are the largest? This infographic shows fantastic illustrations of the 75 largest sea animals, ranked by average size. The detailed visual is organized in descending order of size, starting with the blue whale,...

Bees are crucial for pollination and food security

When animals and insects pick up the pollen of flowers and spread it, they allow plants, including many food crops, to reproduce. The most common pollinator is the bee, but bees are at risk from pollution and pesticides.