The International Union for Conservation of Nature is a global environmental network which conducts scientific research into biodiversity and eco-systems in order to pass on knowledge and influence those in power to help them develop the best laws and practices for people and planet as well as running thousands of projects around the world.
The IUCN operates the Red List of Threatened Species, an internationally recognised authority on the conservation status of plant and animal species across the globe. They use a scientific approach to determine numbers of a species and the risks they are under in order to determine how much of a conservation priority they are. Species and sub-species are placed on a scale which shows how under threat they are.
Extinct - a species is totally extinct
Extinct in the Wild - there may be some species in captivity but none surviving in the wild. Sometimes successful captive breeding programmes can release species back in to the wild as occurred with Prezwalski’s horse which was reintroduced to Mongolia.
The following three fall under the threatened category:
Critically Endangered - the species faces an extremely high risk of extinction.
Endangered - a species faces a very high risk of extinction.
Vulnerable - the species faces a high risk of extinction in the wild.
Near Threatened - a species doesn’t fall under the threatened category but is close to or likely to enter that category in the future.
Least Concern - not threatened - a species in this category could be considered to be widespread and abundant.
Data Deficient - not enough information to make an accurate assessment.
Over 76,000 species of plants and animals were assessed by April 2015, both threatened and non-threatened. Animal species are covered much more than plants, particularly mammals while other areas such as marine species have not been covered in so much detail.