California Condor Grooming (through the fence)

The California Condor (Gymnogyps californianus) is a New World vulture, the largest North American land bird. This condor inhabits northern Arizona and southern Utah (including the Grand Canyon area and Zion National Park), coastal mountains of central and southern California, and northern Baja California. Although other fossil members are known, it is the only surviving member of the genus Gymnogyps.

The plumage is black with patches of white on the underside of the wings and the head is largely bald, with skin color ranging from gray on young birds to yellow and bright orange on breeding adults. Its huge 3.0 meter wingspan is the largest of any North American bird, and its weight of up to 26 lbs. makes it the heaviest bird native to North America. Only the Trumpeter Swan has a comparable weight among native North American birds. The condor is a scavenger and eats large amounts of carrion. It is one of the world's longest-living birds, with a lifespan of up to 60 years.

Condor numbers dramatically declined in the 20th century due to poaching, lead poisoning, and habitat destruction. A conservation plan was put in place by the United States government that led to the capture of all 22 remaining wild condors in 1987. These surviving birds were bred at the San Diego Zoo Safari Park and the Los Angeles Zoo. Numbers rose through captive breeding and, beginning in 1991, condors have been reintroduced into the wild. The project is the most expensive species conservation project ever undertaken in the United States. The California Condor is one of the world's rarest bird species: as of December 2011, there are 390 condors known to be living, including 210 in the wild. The condor is a significant bird to many Californian Native American groups and plays an important role in several of their traditional myths.

The conservation status of a group of organisms (for instance, a species) indicates whether the group is still extant (that is, members of it are still alive) 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, known threats, and so on.

The IUCN Red List of Threatened Species is the best-known worldwide conservation status listing and ranking system. The system divides threatened species into three categories: Critically Endangered (CR), Endangered (EN), and Vulnerable (VU). Also listed are the documented extinctions that have occurred since AD 1500 and taxa that are extinct in the wild. Lower risk taxa are also divided into categories. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) aims to ensure that international trade in specimens of wild animals and plants does not threaten their survival.

Critically Endangered is the highest risk category assigned by the IUCN Red List for wild species. Critically Endangered means that a species is either facing a very high risk of extinction, its numbers have decreased, or will decrease, by 80% within three generations.

As the Red List does not consider a species extinct until extensive, targeted surveys have been conducted, species which are possibly extinct are still listed as 'Critically Endangered.' A new ideal category for 'Possibly Extinct' has been suggested by BirdLife International to categorize these taxa.

The IUCN Red List of Threatened Species (also known as the IUCN Red List or Red Data List), founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature (IUCN) is the world's main authority on the conservation status of species. A series of Regional Red Lists are produced by countries or organizations, which assess the risk of extinction to species within a political management unit.

The IUCN Red List is set upon precise criteria to evaluate the extinction risk of thousands of species and subspecies. These criteria are relevant to all species and all regions of the world. The aim is to convey the urgency of conservation issues to the public and policy makers, as well as help the international community to try to reduce species extinction.

Major species assessors include BirdLife International, the Institute of Zoology (the research division of the Zoological Society of London), the World Conservation Monitoring Centre, and many Specialist Groups within the IUCN Species Survival Commission (SSC). Collectively, assessments by these organizations and groups account for nearly half the species on the Red List.

The IUCN aims to have the category of every species re-evaluated every five years if possible, or at least every ten years. This is done in a peer reviewed manner through IUCN Species Survival Commission (SSC) Specialist Groups, which are Red List Authorities responsible for a species, group of species or specific geographic area, or in the case of BirdLife International, an entire class (Aves).