The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological species. A series of Regional Red Lists are produced by countries and organizations, which assess the risk of extinction to species within a political management unit.
Threatened species are any species which are vulnerable to extinction in the near future. Species that are threatened are sometimes characterised by the population dynamics measure of critical depensation, a mathematical measure of biomass related to population growth rate. This quantitative metric is one method of evaluating the degree of endangerment.
The conservation status of a group of organisms indicates whether the group still exists and how likely the group is to become extinct in the near future. Many factors are taken into account when assessing conservation status: not simply the number of individuals remaining, but the overall increase or decrease in the population over time, breeding success rates, and known threats. Various systems of conservation status are in use at international, multi-country, national and local levels, as well as for consumer use such as sustainable seafood advisory lists and certification. The two international systems are by the International Union for Conservation of Nature (IUCN) and The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).
The ICUN has many ranks that define an animal's population and risk of extinction. Species are classified into one of nine Red List Categories: Extinct, Extinct in the Wild, Critically Endangered, Endangered, Vulnerable, Near Threatened, Least Concern, Data Deficient, and Not Evaluated. They formerly used a identification called "lower risk" to describe some animals.
Ivell's sea anemone is a species of sea anemone in the family Edwardsiidae. It is endemic to a single location, Widewater Lagoon in West Sussex, England, where it was first discovered by Richard Ivell. It has been listed as Data Deficient by the IUCN since 1996.
The New Zealand Threat Classification System is used by the Department of Conservation to assess conservation priorities of species in New Zealand.
Limu, otherwise known as rimu or ʻimu is a general Polynesian term for edible plants living underwater, such as seaweed, or plants living near water, like algae. In Hawaii, there are approximately one hundred names for kinds of limu, sixty of which can be matched with scientific names. Hundreds of species of marine algae were once found in Hawaii. Many limu are edible, and used in the cuisine throughout most of Polynesia.
Endangered species as classified by the International Union for Conservation of Nature (IUCN), are species which have been categorized as very likely to become extinct in their known native ranges in the near future. On the IUCN Red List, endangered is the second-most severe conservation status for wild populations in the IUCN's schema after critically endangered. In 2012, the IUCN Red List featured 3,079 animal and 2,655 plant species as endangered worldwide. The figures for 1998 were 1,102 and 1,197 respectively.
