Different Types and Categories of Endangered Animals

Endangered animal categories, definitions, and lists

A-Z Animals follows the International Union for the Conservation of Nature (IUCN)’s nine categories of endangered animal lists. They are:

	Extinct (EX) — Extinct species no longer exist. After exhaustive research, scientists around the world agree that there isn’t a single living individual of the species on the planet. Interestingly, 99 percent of all species that ever graced the Earth over the past five billion years have gone extinct. Read more and see an  extinct species list here.
	Extinct in the wild (EW) — Species that only survive in captivity, cultivation, or outside their native range are deemed “extinct in the wild.” For example, if only 10 individuals of a rare bird are left, and they all live in zoos or on a single nature preserve, the IUCN would classify the species as extinct in the wild. Read more and see an  extinct in the wild species list here.
	Critically endangered (CR)  — Critically endangered species are on the brink of becoming extinct or extinct in the wild but have not yet met the criteria for either category. See a  list of critically endangered species here.
	Endangered (EN) — Endangered species are at a very high risk of becoming extinct in the wild or extinct. For an animal to be added to the category, it must meet specific criteria regarding population or habitat decline, which you can read about on our  endangered species list.
	Vulnerable (VU) — Vulnerable species meet at least one of the five Red List criteria. They’re considered to be at high risk of human-caused extinction if conservationists don’t intervene. For the IUCN to add a taxon to the Vulnerable animals list, it must meet specific criteria regarding population or habitat decline. Read more on our  vulnerable species list here.
	Near threatened (NT) — A species is considered Near Threatened when it doesn’t qualify as Critically Endangered, Endangered, or Vulnerable, but scientists believe it will reach one of those levels in the near future. See our  near threatened species list here.
	Least concern (LC) — Species that fall into the Least Concern category are not presently facing any population or habitat declines. See a  least concern species list.
	Data deficient (DD) — Data deficient species lack enough information to properly categorize into one of the groups above. See a data deficient species list.
	Not evaluated (NE) — This species has not been evaluated for an IUCN categorization yet. See a  list of not evaluated species.

What is the International Union for the Conservation of Nature (IUCN)?

The IUCN is the organization that monitors the conservation status and other ecological metrics for the world’s plants and animals. Its mission is to promote sustainable use of the Earth’s resources.Founded in 1948, in Fontainebleau, France, as the Union for the Protection of Nature, the IUCN is the oldest global environmental advocacy group. Today, headquartered in Gland, Switzerland, the umbrella organization collaborates with over 1,000 smaller nonprofits, associations, and governments representing 140 countries.

How Many Species Occupy the Earth?

The IUCN monitors the world’s species, which raises the question: How many species currently occupy the planet?In 2016, researchers declared their collective belief that over one trillion species currently occupy the Earth. However, scientists have only observed and described about one-thousandth of one percent of them, or 7 to 10 million.The typical lifespan of a species is 10 million years. However, some stick around for hundreds of millions of years. For example, jellyfish have lived on Earth for nearly 550 million years!

What is a Taxon?

The IUCN frequently uses the word “taxon.” So what is it? A taxon is a group of one or more populations of a species or organism that form a unit.

What is the Red List?

The International Union for the Conservation of Nature is perhaps best known for creating the IUCN Red List of Threatened Species, a detailed accounting of the world’s vulnerable and endangered species. The list started in 1964 and details at-risk taxons, for both plants and animals, which are separated into several categories.

How Many Animals are Currently Endangered?

You may be wondering: How many animals are endangered, or what animals are endangered in 2020? For the most recent version of the list, IUCN researchers and scientists evaluated 63,837 species. Of that number, 19,817 are threatened with extinction; 3,947 landed in the Critically Endangered category; 5,766 qualified as Endangered, and over 10,000 species are listed under Vulnerable.

What is the Endangered Species Act?

Passed in 1973, the Endangered Species Act is a federal United States law designed to protect threatened and endangered species that are imperiled because of a “consequence of economic growth and development untempered by adequate concern and conservation.” The goal of the act is to prevent extinction and recover species to the point where they no longer need protection.

Extinct Animals

Seymouria

Although Seymouria had so many reptilian features, it was an amphibian

Gorgosaurus

Gorgosaurus probably lived and hunted in packs.

Josephoartigasia monesi

Josephoartigasia monesi the largest known rodent

See all of our extinct animals.

Extinct in the Wild Animals

Toxodon

Scimitar-horned Oryx

Believed to be the inspiration for unicorn myths!

Elephant Bird

Vorombe titan, a type of elephant bird, is the largest bird that ever lived

See all of our extinct in the wild animals.

Critically Endangered Animals

Gooty Sapphire Tarantula

They can run up a tree trunk surprisingly fast.

Onagadori Chicken

The Onagadori, the chicken with the world's longest tail, was declared a Natural Monument of Japan in 1952.

Aruba Rattlesnake

This rattlesnake only lives on the island of Aruba.

See all of our critically endangered animals.

Endangered Animals

Florida Panther

Florida panthers can leap more than 4.5 meters (15 feet) in the air.

Black-Footed Ferret

Black footed ferrets are the only ones native to North America.

Earless Monitor Lizard

These lizards can practically shut down their metabolism and appear comatose for long periods.

See all of our endangered animals.

Vulnerable Animals

Indian Star Tortoise

Popular in the exotic pet trade!

Marmoset

Golden Mole

The golden mole is so named because of its iridescent coat, which gives it a shining, rainbow-like effect.

See all of our vulnerable animals.

Near Threatened Animals

Common Grackle

Common grackles are a pest species that damage crops and spread disease.

Siberian Ibex

There’s a population of Siberian ibex in New Mexico

Alaskan Pollock

It's one of the most commonly eaten fish in the world

See all of our near threatened animals.

Least Concern Animals

Crappie Fish

The crappie is one of the most popular freshwater fish in North America.

Sea Slug

All sea slugs have both male and female sex organs

Fancy Mouse

Fancy mice are beloved pets with a history of domestication spanning thousands of years!

See all of our least concern animals.

Data Deficient Animals

Ground Squirrel

Ground squirrels are adept excavators and can dig colonial burrows larger than football fields!

Bigfin Reef Squid 

Can change color through use of chromatophores

Leptocephalus

Leptocephali have flat bodies filled with jelly-like substances, surrounded by a thin layer of muscle.

See all of our data deficient animals.

Not Evaluated Animals

Earthworm

They are hermaphrodites, which means they have male and female organs

Sandworm

Legs also function as gills

Keta Salmon

During spawning the look of the male changes. Among other things, he grows a beak called a kype that bears fangs.

See all of our not evaluated animals.

The Big List of Endangered Animals

List of Extinct Animals

List of Extinct in the Wild Animals

List of Critically Endangered Species

List of Endangered Species

List of Vulnerable Species

List of Near Threatened Species

List of Least Concern Species

List of Data Deficient Species

List of Not Evaluated Species

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