The data included in the 2018 version of the Status of Birds website were downloaded from the IUCN (2018). 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. BirdLife International is the IUCN Red Listing Authority for birds and maintains the most up to date information on global bird distributions.
The IUCN 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) but also includes species that have been evaluated to have a low risk of extinction (classified as Least Concern), and those that are extinct. While only a small number of the world’s plant and animal species have been assessed, birds are one of the groups that have been comprehensively assessed.
IUCN categories are at the global scale; species status may be quite different when considered at a national or regional scale.
Please visit the IUCN Categories and Criteria website for more information on the use and interpretation of categories and a full definition of criteria. Please visit the IUCN Red List of Threatened Species website to see the full list of species and for more information about the list.
Please visit the BirdLife International website for more information on the organization.