A very high risk of extinction in the wild. How many are left turns out to be only half of what puts a species in this category.
One category further down the Red List. The same threats, with less time left.
Critically Endangered
Critically Endangered
Critically Endangered
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Critically Endangered
Critically Endangered
Critically Endangered
Critically Endangered
Critically Endangered
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Critically Endangered
Critically EndangeredEndangered is the middle of the three threatened categories on the IUCN Red List of Threatened Species, above Vulnerable and below Critically Endangered. A species qualifies on a population reduction of at least 50% over ten years or three generations, or at least 70% where the cause is understood and ongoing. It also qualifies on size alone, at fewer than 2,500 mature individuals, or fewer than 250 under the criterion for very small populations.
The thing worth understanding about this category is that the numbers can look large. A species with tens of thousands of animals left can be Endangered if the rate of loss is steep enough, because the Red List measures trajectory as well as headcount. A population that halves every decade is in trouble regardless of where it started.
The threats are the familiar ones and they rarely arrive alone. Habitat is cleared or fragmented, which pushes animals into contact with people, which produces conflict, which produces killing. Hunting and trade take adults faster than they can be replaced. For marine and freshwater species, bycatch and dams do the same work. Each of these is survivable on its own and much less so in combination.
This is also the category where conservation most visibly pays. There is usually enough population left that protecting habitat and stopping the direct killing produces a measurable response within a decade or two, which is fast by the standards of this work. That is why the organizations on these pages concentrate here: it is where a given amount of money moves the number most.
Discover endangered species around the world.
Endangered is an IUCN Red List category meaning a species faces a very high risk of extinction in the wild. A species qualifies if it has declined by 50% or more over ten years or three generations, or if fewer than 2,500 mature individuals remain.
Severity. Endangered means a very high risk of extinction, generally a 50% to 70% decline or fewer than 2,500 mature individuals. Critically Endangered is the step above it: an 80% or greater decline, or fewer than 250 mature individuals, and it is the last category before Extinct in the Wild.
No. Threatened is the umbrella term for three IUCN categories together: Vulnerable, Endangered, and Critically Endangered. Endangered is one of the three. In United States law the Endangered Species Act uses threatened differently, as a category below endangered, which is a common source of confusion.
The IUCN Red List had assessed 172,620 species as of March 2026, and roughly 49,500 of them are threatened with extinction across the Vulnerable, Endangered, and Critically Endangered categories combined. Most species on Earth have never been assessed, so the true number is unknown.
Yes, and this is the category where it happens most often. Enough population usually remains that protecting habitat and stopping the direct cause of death produces a measurable recovery within one or two decades, provided the funding lasts that long.
