FAQ: What is the difference between a "vulnerable" and an "endangered" species?

A threatened species is a species of plant or animal that is not currently endangered, but may become so if its population continues to decrease. In most cases it is human action which has caused the population to decrease so we must be really careful to change what we do that impacts upon the species or their habitat.

If we fail to protect a threatened species, they may become a endangered species.

"Threatened species" is also used as a general description of species under all levels of threat - vulnerable, endangered and critically endangered.

Governments in NSW, Australia and internationally have recognised that threatened species need protecting. The first step to doing that is defining and describing which species are threatened. The next steps are then to work out what is causing the problem and then what we can do about it. In this FAQ we are just looking at definitions.

International

IUCN Red List

Used internationally to refer to any species listed as Critically Endangered, Endangered, or Vulnerable according to the IUCN Red List of Threatened Species definitions. According to US Federal law, a threatened species is a species that is likely to become endangered in the foreseeable future.

The IUCN Red List of Threatened Species™ provides taxonomic, conservation status and distribution information on plants and animals that have been globally evaluated using the IUCN Red List Categories and Criteria. This system is designed to determine the relative risk of extinction, and the main purpose of the IUCN Red List is to catalogue and highlight those plants and animals that are facing a higher risk of global extinction (i.e. those listed as Critically Endangered, Endangered and Vulnerable). The IUCN Red List also includes information on plants and animals that are categorized as Extinct or Extinct in the Wild; on taxa that cannot be evaluated because of insufficient information (i.e., are Data Deficient); and on plants and animals that are either close to meeting the threatened thresholds or that would be threatened were it not for an ongoing taxon-specific conservation programme (i.e., are Near Threatened).