California condors are extremely endangered. In the late 1970's, the species was reduced to a population of less than 25 birds. Scientists hoped to maintain a wild population but when the species continued to decline, every remaining individual was rounded up and the last wild G. californianus was captured in 1987. After several years of a successful captive breeding program in Los Angeles and San Diego, the first two condors were reintroduced to a California wild sanctuary in 1991. More than a dozen Condors have since been reintroduced but the mortality rate is high and the wild socialization of captive-bred birds has been difficult. More than 120 G. californianus are now living; the majority are still captive but there is a long term plan of continued breeding and wild release. The exact causes of California condors' rapid decline in the past decade is uncertain, although the species has been known to be threatened since the late 19th century. Factors contributing to the decline include poisoning, chemical pollution, loss of habitat and loss of food resources, as well as a historical problem of hunting and scientific over-collection.
Condors' consumption of poisoned bait meat, put out by ranchers and intended for coyotes, as well as lead poisoning from bullets in animals killed by ranchers, have been the reported cause of some condor deaths. The presence of pesticide DDT in condor habitats led to problems with breeding and brittle eggshells that further reduced the reproductive capability of these already slow-multiplying birds. The loss of habitat, erection of electrical and telephone lines in the habitats, and loss of prey populations have all also been damaging to the condors.
In the past, especially during the early European exploration of California, sport hunting and scientific collection of eggs and skins threatened G. californianus populations.
( http://www.peregrinefund.org/condview.html; Mountfort 1988; Schorsch 1991)
IUCN Red List of Threatened Species: critically endangered