The 10 Most Endangered Species on Earth — And How to Help

Portrait shot of a big western lowland gorilla
Nick Fox/

Written by Lex Basu

Updated: November 13, 2023

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Key Points:
  • The most endangered animal on the planet is the saola (Asian unicorn), which was first discovered in 1992 in the forests on the Laotian-Vietnamese border. They look like antelopes but are more closely related to cattle, and have spindly, pointed horns that can grow up to 20 inches long.
  • Found in the Primorye region of Russia and China, the Amur Leopard is the most endangered cat. Due to poaching, fires, habitat destruction, and complications wrought by inbreeding, researchers believe only 90 still exist in the wild.
  • The main enemy of the vaquita (Gulf of California harbor porpoise) is the fishing industry, namely, gillnets used for illegal totoaba fishing. There’s only nine of these 4-5 foot long porpoises left in the world.

What are the most endangered animals in the world? Surprisingly, conservationists can’t agree on a universal top 10 list. Why? Well, for starters, populations are perennially in flux. Secondly, researchers use various models that disparately weigh contributing factors — like decline rates and community fragmentation. The result is a spectrum of endangered species instead of a definitive top 10 roster.

Overview of the Most Endangered Species on Earth

But experts all agree that animals listed on the International Union for the Conservation of Nature’s Red List need help. So, to help spread the word about vulnerable species, we’ve handpicked 10 Critically Endangered animals on the brink of extinction to highlight. Let’s dive in!

Most Endangered Animal: Saola (Pseudoryx nghetinhensis)

Saolas are one of the most endangered animals on the planet — and the most elusive! Affectionately dubbed “Asian unicorns,” saolas (pronounced “saw-las”) evaded human detection till 1992! To date, wildlife cameras have only caught three.

Because saolas are so scarce, researchers know precious little about these herbivores that live in wet forests on the Laotian-Vietnamese border. Thanks to local sightings and a smattering of short scientific studies, we also know that saolas are crepuscular and typically travel alone or with a single partner. With their silky, short coats, saolas look a lot like antelopes but are most closely related to cattle. Uniquely, both males and females sport spindly, pointed horns that can reach 20 inches long!

A single female named Martha lived in captivity under the observation of William Robichaud, coordinator of the IUCN’s Saola Working Group. But the doe died 15 days in, and researchers gathered little data. However, the group noticed that Martha was tame with humans but deeply distressed around dogs.

Habitat loss, illegal fur trading, population fragmentation, abandoned boar traps, and the traditional medicine black market all threaten saolas, making them one of the world’s most endangered species. Learn more about saolas.

Saola Endangered Species Infographic

The Saola is one of the most endangered and elusive species on the planet.

Most Endangered Bird: Kakapo (Strigops habroptilus)

A large, ground-dwelling, nocturnal, flightless parrot, kakapos are native to New Zealand and rank among the world’s most endangered birds. Also known as the “owl parrot,” these herbivores have yellow and green plumage, huge feet, short legs, and giant beaks. They’re also the heaviest parrots on the planet and one of the longest-living birds known to man.

Today, only about 252 kakapos live on two small islands, Whenua Hoa and Anchor Island, which conservationists scrubbed of cats, rats, and ferrets — owl parrots’ main predators. The Kakapo Recovery team is clearing a third island for the Critically Endangered bird in the hopes of further bolstering their numbers. Learn more about kakapos.

A kakapo perched on a mossy tree branch surrounded by green foliage.

Only about 209 kakapos live on two small islands in New Zealand, where conservationists eliminated the bird’s main predators.

Most Endangered Fish: Southern Bluefin Tuna (Thunnus maccoyii)

The IUCN, alongside Greenpeace and dozens of other conservation groups, lists the Southern Bluefin Tuna as Critically Endangered. Governments have even passed laws criminalizing their capture. But loopholes render the statutes toothless, and fishers regularly scoop bluefin tunas out of the Southern Hemisphere’s waters.

Pollution is also a massive problem for the species — as are disease-causing chemicals that marine ranchers use to kill algae.

Four bluefin tuna swimming in the ocean.

Overfishing, pollution, and disease-causing chemicals contribute to the endangered status of the bluefin tuna.

Most Endangered Big Cat: Amur Leopard (Panthera pardus orientalis)

Coveted for their pelts and bones, Amur leopards are an exceptionally vulnerable big cat. Researchers believe only 60 to 80 remain in the wild — and their numbers are plummeting due to poaching, fires, habitat destruction, and complications wrought by inbreeding.

These cold-weather cats live exclusively in the Primorye region of Russia and China. Scientists caution that Amur leopards now only occupy two percent of their historical territory due to the ravages of climate change. Learn more about Amur leopards.

An Amur leopard lounging on a tree stump.

Scientists believe that Amur leopards now only occupy 2% of their historical territory due to climate change.

Most Endangered Whale: North Atlantic Right Whale (Eubalaena glacialis)

Named by their human predators, North Atlantic right whales stick close to coasts and regularly skim the ocean’s surface for zooplankton, making them easy targets — or “the right whales to hunt.”

Thousands of these gentle, aquatic giants once torpedoed through Atlantic waters. But today, only about 350 are left, and fewer than 100 are breeding females. These numbers worry conservationists because right whales only give birth once a decade.

Boating accidents, rising sea temperatures, and fishing net entanglements plague the whale — as does increased noise pollution, which prevents them from communicating and finding food. Learn more about different whale species.

A North Atlantic right whale swimming in the ocean close to the surface.

Less than 100 breeding female North Atlantic right whales are left in the world.

6 Other Animals Facing Extinction

Vaquitas (Phocoena sinus)

They’re shy, love squid, and only around 10 are left in the wild. Known as the “Gulf of California harbor porpoise,” vaquitas — cousins to the blue whale — are the smallest and most endangered marine mammals in the world.

Vaquitas’ main nemesis is the fishing industry. Specifically, the 4-5 foot-long swimmers drown after becoming entangled in gillnets used for illegal totoaba fishing. Even though officials made gillnets illegal in vaquita waters, officials don’t enforce the law.

Pollution from the Colorado River doesn’t help the problem, and conservationists believe the species could become extinct in the wild within a handful of years. Learn more about porpoises.

A porpoise swimming and looking at the camera

Only nine known vaquitas, also known as the Gulf of California harbor porpoise, are left in the world.

Javan Rhinos (Rhinoceros sondaicus)

Residents of Indonesia’s Ujung Kulan National Park, Javan rhinos are one of the most endangered species currently clinging to their patch of the planet. According to recent counts, only 76 are left. Inbreeding, natural disasters, disease, human encroachment, poaching, and the proliferation of ruinous palms are all conspiring against the 5,000-pound herbivores.

Though they weigh twice as much as the average car, Javan rhinos, also known as “Sunda rhinos,” are the shyest and most endangered of the five rhino species. How introverted are they? Instead of vocalizing, the leathery behemoths use dung and urine to communicate! But don’t confuse their quiet natures with weakness. When threatened, rhinos are ferocious and easily kill humans who get in their way.

Javans typically live for 40 years, but pregnancies are few and far between, with a long 19-month gestation period. As a result, they’re incredibly vulnerable because regeneration efforts are slow going. Learn more about Javan rhinos.

A Javan rhino in a zoo enclosure.

The Javan rhino is the most endangered of the five rhino species.

Mountain Gorillas (Gorilla beringei beringei)

A subspecies of the eastern gorilla first observed in 1902, mountain gorillas live high in the Congo Basin’s forests. Their woolly, thick hair keeps them warm in sub-zero temperatures, and the hearty primates have struggled to survive decades of civil unrest in their region.

Though the mountain gorilla’s situation is improving slightly, they still qualify as one of the most endangered animals in the world as there are only about 880 left in the wild. Poaching is up, as is illegal charcoal making, which is destroying their habitats at alarming rates. Plus, human encroachment is forcing the gorillas to higher ground, and many aren’t adapting well. Learn more about mountain gorillas.

A large gorilla walking through a green forest.

Poaching, habitat destruction, and human encroachment are contributing factors in the mountain


‘s declining population numbers.

Sea Turtles (Eretmochelys imbricata and Lepidochelys kempii)

Hawksbill and Kemp’s ridley sea turtles are Critically Endangered. Their numbers have declined by about 80 percent over three generations.

Since climate determines the sex of sea turtle hatchlings (febricity gives way to females), rising sea temperatures are wreaking havoc on populations because there aren’t enough males to mate!

Despite being illegal, sea turtle poaching is a persistent problem. The animals are still sought-after delicacies in parts of the world. Plus, their shells are highly-prized status symbols in some cultures. Also, and unfortunately, sea turtles regularly fall victim to commercial fishers who inadvertently scoop them up as bycatch. By the time they’re discovered, it’s often too late.

Coastal development is also killing Hawksbill and Kemp’s ridley sea turtles, as is pollution. Learn more about sea turtles.

Sea Turtle Sitting on Moss by Rocks

Climate determines the sex of sea turtle hatchlings, and rising sea temperatures have skewed the ratio of males to females.

Sumatran Elephants (Elephas maximus sumatrensis)

In 2011, Sumatran elephants landed under the Critically Endangered category on the IUCN’s Red List. Humans are overtaking their territories, and hunters illegally kill the pachyderms for their horns. Sadly, elephant shootings are up among farmers protecting their harvests.

Sumatran elephants are elemental seed spreaders. The pollination keeps their forest ecosystems healthy and vibrant, and their loss could trigger a devastating domino effect that renders dozens of species extinct in a record time. Learn more about Sumatran elephants.

Sumatran elephant

Shootings of the Sumatran elephant are on the rise by farmers attempting to protect their crops.

St. Lucia Racer Snake (Erythrolamprus ornatus)

Currently, the St. Lucia racer snake is said to be the world’s most endangered snake. There’s only 18 of these rare snakes left on the island of Maria Major in St. Lucia, where they make their home. The largest threat to the St. Lucia racers, which once populated the whole island, are invasive species like mongooses. St. Lucia racer snakes are non-venomous and grow up to four feet long.

How to Help the World’s Most Endangered Species

How can you help the species on our top 10 most endangered animals list? The most effective things you can do are:

  • Financially support conservation groups.
  • Research and boycott brands that lobby against eco-conscious laws that will save the planet.
  • Volunteer for organizations working on anti-pollution and climate change initiatives.
  • Talk with and educate your friends and family about vulnerable species that are going extinct.

Do you agree with our choices for most endangered animals? Let us know in the comments! And keep up the excellent work of learning about the world’s species.

Summary of 10 Most Endangered Species on Earth — And How to Help

Let’s look back at the 10 most endangered species inhabiting the Earth:

2Kakapo Bird
3Southern Bluefin Tuna
4Amur Leopard
5North Atlantic Right Whale
7Javan Rhino
8Mountain Gorilla
9Sea Turtle
10Sumatran Elephant

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About the Author

Lex is a green-living, tree-hugging, animal-lover, who at one time was the mother to twenty one felines and one doggo. Now she helps pet owners around the globe be the best caretakers for their most trusting companions by sharing her experience and spreading love.

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