IUCN Red List

Also called: Red List of Threatened Species · Topic: Biodiversity and its Conservation · NCERT: Class 11, Ch 14 "Biodiversity and Conservation"

Meaning

The IUCN Red List of Threatened Species is a world list, run by IUCN since 1964, that gives each species a conservation status: a label for how close it is to extinction (when the last member of a species dies). It uses nine categories, from Extinct (EX) down to Least Concern (LC), plus Data Deficient (DD) and Not Evaluated (NE).

It matters because it is the main scientific measure of extinction risk across the world. Countries and conservation groups use it to decide which species need help first. It is a science list only, so it has no legal force in India.

Explanation

The organisation behind it: IUCN

• IUCN (International Union for Conservation of Nature) studies nature and advises on how to protect it.
• Founded: 1948, at Fontainebleau (France).
• Headquarters: Gland, Switzerland.
• Members: states, government agencies and NGOs (non-government organisations), all in one union. It is not a UN body.

• India has been a state member since 1969.

• Name trap: NCERT Class 11 calls it the "International Union of Conservation of Nature and Natural Resources". This is its older name. The short name is still IUCN.

• Its main jobs:
• It runs the Red List.
• It advises on protected areas (national parks, sanctuaries and similar areas).
• It advises UNESCO on natural World Heritage Sites.

• It holds the World Conservation Congress, its top meeting.

• World Conservation Congress 2025: held in Abu Dhabi, UAE, 9–15 October 2025. It was the first Congress in the UAE, with more than 10,000 attendees [3][4].

• Members adopted 148 Resolutions and the Abu Dhabi Action Plan, which has five areas for action [3][4].
• Razan Khalifa Al Mubarak was re-elected IUCN President [3].
• IUCN adopted its first policy on synthetic biology (making or changing living things in a lab), and the first World Summit of Indigenous Peoples and Nature was held there [4].

The categories: old scheme and current scheme

• NCERT's old scheme (used before 1994) had three groups:
• Endangered: in danger of extinction. Examples: red panda, Bengal tiger, Asian elephant.
• Vulnerable: numbers have fallen sharply, and the species is likely to become endangered soon if threats continue. Examples: snow leopard, one-horned rhinoceros.

• Rare: very small populations, living in a small area or thinly spread over a wide one. "Rare" is no longer an IUCN category. A rare species may be naturally small in number but stable.

• Current scheme: Categories and Criteria, version 3.1. It was approved by the 51st meeting of the IUCN Council, Gland, on 9 February 2000. A second edition came out in 2012 [5].

Category	Code	Meaning in simple words
Extinct	EX	No reasonable doubt that the last individual has died [5]
Extinct in the Wild	EW	Survives only in captivity, in cultivation, or as a population living far outside its old range [5]
Critically Endangered	CR	Extremely high risk of extinction in the wild [5]
Endangered	EN	Very high risk of extinction in the wild [5]
Vulnerable	VU	High risk of extinction in the wild [5]
Near Threatened	NT	Not threatened now, but close to qualifying soon [5]
Least Concern	LC	Widespread and common [5]
Data Deficient	DD	Not enough data to judge. Not a threat category [5]
Not Evaluated	NE	Not yet checked against the criteria [5]

• "Threatened" means CR + EN + VU only. NT, LC, DD and NE are not threatened.

How a species is placed: the five criteria (A–E)

• A species goes into CR, EN or VU if it meets any one of the criteria A to E [5].
• A: the population is falling, measured over 10 years or 3 generations, whichever is longer.
• B: the species lives in a small area. This is measured as extent of occurrence (EOO: the area inside a line drawn around all known sites) or area of occupancy (AOO: the area the species actually uses).
• C: the population is small and still falling.
• D: the population is very small or lives in a very small area.

• E: a mathematical model shows the extinction probability (the chance it will die out).

• Mature individuals are adults able to breed. Young animals are not counted.

Criterion	CR	EN	VU
A2: population fall	≥ 80%	≥ 50%	≥ 30%
B1: extent of occurrence	< 100 km²	< 5,000 km²	< 20,000 km²
C: mature individuals, still falling	< 250	< 2,500	< 10,000
D: mature individuals	< 50	< 250	< 1,000
E: chance of extinction	≥ 50% in 10 yrs / 3 generations	≥ 20% in 20 yrs / 5 generations	≥ 10% in 100 yrs

(All thresholds from [5].)

Latest size and changes (update of 10 October 2025)

• 172,620 species assessed, of which 48,646 are threatened [2]. (NCERT-era figure: over 170,000 assessed, over 47,000 threatened.)
• Hooded seal (Arctic): Vulnerable → Endangered, because global warming is melting the sea ice [2].
• Bearded seal and harp seal (Arctic): Least Concern → Near Threatened. These seals need sea ice to breed, raise pups, moult and rest [2].
• Green sea turtle (global): Endangered → Least Concern. Conservation work raised its numbers by about 28% since the 1970s [2].
• Birds: of 11,185 species assessed, 1,256 are threatened (11.5%). 61% of species are declining, up from 44% in 2016. The main cause is habitat loss from farming and logging [2].

Where it occurs

• Who runs it and since when: IUCN, from Gland, Switzerland. The list started in 1964. It covers species all over the world.
• India: Critically Endangered (CR)
• Gharial: Chambal river (Rajasthan, Madhya Pradesh, Uttar Pradesh) and other north Indian rivers.
• Great Indian Bustard: grasslands of Rajasthan and Gujarat.
• White-rumped vulture and long-billed vulture: across the plains of India.
• Pygmy hog: tall grasslands of Assam (Manas area).

• Hangul (Kashmir stag): Dachigam, Jammu and Kashmir. It is CR in national listings.

• India: Endangered (EN)

• Bengal tiger, Asian elephant: forests across India.
• Red panda: eastern Himalaya (Sikkim, Arunachal Pradesh, Darjeeling in West Bengal).
• Gangetic river dolphin: Ganga–Brahmaputra river systems.
• Asiatic lion: Gir, Gujarat. It is assessed as a subpopulation.

• Lion-tailed macaque, Nilgiri tahr: Western Ghats (Kerala, Tamil Nadu, Karnataka).

• India: Vulnerable (VU)

• Snow leopard: high Himalaya (Ladakh, Himachal Pradesh, Sikkim).
• One-horned rhinoceros: Kaziranga (Assam), and also West Bengal and Uttar Pradesh.
• Dugong: Gulf of Mannar, Palk Bay, Andaman and Nicobar.

• Olive ridley turtle: mass nesting on the Odisha coast.

• World: the Arctic for hooded, bearded and harp seals, and the oceans worldwide for the green sea turtle [2].

• Same category in both schemes: the tiger and the elephant were "endangered" in NCERT's old scheme and are still Endangered. The snow leopard and the rhino are still Vulnerable.

Don't confuse with

• Wildlife (Protection) Act, 1972 schedules: these are India's legal lists, and Schedule I gives the highest protection. The Red List is a global science list with no legal force. A species can be in Schedule I but only "Vulnerable" or even "Least Concern" on the Red List.
• "Rare" (old NCERT category): this was dropped after 1994 and is not in version 3.1. A rare species is not always threatened.
• Near Threatened / Data Deficient: neither is a threat category. Only CR, EN and VU count as "threatened" [5].
• Extinct (EX) vs Extinct in the Wild (EW): EX means the last individual has died. EW means the species still survives, but only in captivity, in cultivation, or outside its old range [5].

Prelims Hooks

• IUCN: founded 1948 at Fontainebleau, with its headquarters at Gland, Switzerland. India has been a state member since 1969. The Red List started in 1964.
• Order of risk: EX > EW > CR > EN > VU > NT > LC. DD and NE stand outside this ranking. "Threatened" = CR + EN + VU only [5].
• CR thresholds: fewer than 50 mature individuals (criterion D), or extent of occurrence under 100 km² (criterion B1) [5].
• October 2025 update: 172,620 assessed, 48,646 threatened. The green sea turtle moved from EN to LC, and the hooded seal moved from VU to EN [2].
• Matching: Great Indian Bustard – CR – Rajasthan/Gujarat. Pygmy hog – CR – Assam. Red panda – EN – eastern Himalaya. Olive ridley – VU – Odisha coast.
• Trap: "IUCN status = Schedule I status" is false. Legal protection in India comes from the Wildlife (Protection) Act schedules.

Mains Points

• Why Indian species become threatened (GS-III):
• Grasslands are treated as "wasteland" and turned into farms, solar parks and power lines. Great Indian Bustards die when they hit power lines, and the pygmy hog loses its home.
• River dams and pollution harm the gharial and the Gangetic dolphin.

• Vultures died after eating dead cattle that had been given diclofenac (a cattle painkiller).

• Linking the science list with the legal list: the Red List uses measured data (population fall, range, size and extinction chance), while the Wildlife Act schedules follow legal priorities. Linking the two would help India spend money and effort on the species in real danger.

• Recovery is possible, but climate is a new threat:
• The green turtle's move to Least Concern shows that long-term protection works [2]. In India, the rhinos of Kaziranga and the lions of Gir recovered from very small numbers living in one place.
• Loss of Arctic sea ice is pushing seals towards extinction [2]. Climate change threatens 43% of natural World Heritage sites [3]. In the Himalaya, the snow leopard and red panda face similar pressure as their habitats shift uphill.

Related concepts

• IUCN
• Threatened species
• Endangered species
• Vulnerable species
• Rare species

Read more

• Threatened species: IUCN and the Red List