The International Union for Conservation of Nature (IUCN) is the world's largest and oldest global environmental organization, aiming to help find solutions to the most pressing environmental problems our world faces.

The IUCN is behind the Red List of Threatened Species, which provides the conservation status and information of animals, plants and fungi using their specifically developed criteria. This list catalogs creatures in different statuses, from least concern, near threatened, vulnerable, endangered, critically endangered, extinct in the wild to extinct.

There are currently 4,898 species listed as critically endangered. This means that they still exist in the wild but are at high risk of extinction because of their declining numbers. In the IUCN spectrum, they are only two levels away from complete extinction from the face of the Earth.

Here are some critically endangered species in the world.

1. Golden bamboo lemur (Hapalemur aureus)

Location: Humid forests and marshes in Southeastern Madagascar

Current population trend: Declining

Threats: hunting and habitat loss due to slash-and-burn agriculture and bamboo harvesting

This Madagascar native is losing its home due to increasing human activities in its areas. There are only an estimated 630 golden bamboo lemurs in total and their numbers continue to decrease over time.

2. Hawksbill turtle (Eretmochelys imbricata)

Location: Migratory; found in tropical and subtropical waters of the Atlantic, Pacific and Indian Oceans

Current population trend: Declining

Threats: Egg collection, tortoiseshell trade, slaughter for meat and habitat loss due to pollution

The Hawksbill turtle population has been on a decline due to the destruction of their nests and pollution of the oceans. Their shells are also traded for decoration and their meat is eaten in foreign delicacies even though hunting them is illegal in many countries.

3. Sunda pangolin (Manis javanica)

Location: Primary and secondary forests in several Southeast Asian countries including Myanmar, Thailand, Vietnam and Cambodia

Current population trend: Declining

Threats: Poaching for their meat and scales to the Chinese market

There is actually not much information on the pangolin because they are hard to study due to their elusive and nocturnal nature. However, these adorable mammals are unfortunately still traded in several countries, particularly for their meat used in exotic dishes.

4. Ivory-billed woodpecker (Campephilus principalis)

Location: Originally located in hardwood and montane forests in the United States and Cuba

Current population trend: Declining

Threats: Habitat loss due to logging and clearance for agriculture; hunting

This huge woodpecker is mainly black and white and resembles a duck when flying. There has been a lack of confirmed sighting in the U.S. since 1994, while in Cuba, there are some reports of recent sightings. The population is most likely tiny, though, estimated to fewer than 50 individuals.

5. Javan rhinoceros (Rhinoceros sondaicus)

Location: Lowland tropical rainforest areas in Indonesia and Vietnam

Current population trend: Unknown

Threats: Poaching due to the demand for rhinoceros horn and other products for Chinese medicine systems

The Javan rhinoceros used to occupy several other countries in the Southeast Asian region such as Myanmar, Thailand and Cambodia, but their steady decline has left them with less than 50 mature individuals.