Threats
habitat alteration, urbanization, poisoning, shooting, colliding into power lines, pesticides, unknown factors
STATUS:
ESA -- ENDANGERED
(extinct in the wild)
IUCN -- CRITICALLY ENDANGERED
SIZE:
Length
45-55 inches (114-140 cm)
Weight
20-23 pounds (9-10 kg)
Wingspan:
9.1 feet (2.8 m)
HABITAT:
Rocky cliffs in mountainous terrain away from human disturbance; nearby open grasslands for feeding
POPULATION:
100 in captivity
CURRENT RANGE:
Captive-breeding facilities
in southern California
CONSERVATION:
Captive-breeding
programs in effect; banning of dangerous pesticides; Species Survival Plan in
effect; CITES
trade restrictions;
re-introduction efforts
When California condors were brought into zoos and bred in captivity, the young were fed by caretakers using hand puppets shaped like the heads of adult California condors. This was done to avoid imprinting (a learning mechanism by which young birds identify a particular object as their parent). Condors raised by this method and released into the wild were partly successfulÑthey did learn to hunt for food, but so far they have not bred.
During the winter of 1985-1986, four of the five known breeding pairs of wild California condors lost at least one member. In an attempt to save the species, all the remaining wild birds were rounded up for captive-breeding programs. This was one
of the most controversial environmental decisions made in this century, because it could have backfired. There are now about 100 California condors alive, most of them in captivity. 27 California condors have been released
since 1992.
The U.S. Fish and Wildlife Service has plans to release captive-bred condors in the Vermillion Cliffs, a remote part of
the Glen Canyon National Recreation Area in northern Arizona. The area was part of the condor's ancient range. The goal is to build a self-sustaining population of about 150 birds over several decades. Local landowners initially objected to the planned release, fearing restrictions that might result from the birds' endangered status. To ease these concerns, the birds have been labeled "nonessential," which means that they're not vital to captive-
breeding programs.
Just as this guidebook was
going to press in December, 1996,
six condors were released into the wild in Arizona.
We wish them well.
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Ancient Wings
The largest animal in the North American sky is the California condor. Its wings spread nearly 10 feet tip to tip; and at 20-23 pounds, it
is the heaviest flighted bird. Soaring high on huge broad wings,
California condors reach speeds of more than 55 miles per hour (90 km/h) and altitudes of 15,000 feet (4,575 m). They cover hundreds of miles a day in their quest for food.
Beyond their spectacular size and appearance, California condors are a living link to the Ice Age. Ten thousand years ago, California condors roamed from the western U.S. all the way to what is now New York State. Like all vultures, condors are carrion eaters; and in the ancient past, they fed off the remains of large animalsÑbison, mammoths, and camelsÑthat populated North America.
But by the 1940s, their range had been reduced to a narrow arc north of Los Angeles. By the 1960s, there were only about 60 California condors left. They were recognized as an endangered species in 1967. Thirty years later, the domain of the California condor has shrunk to a few captive enclosures in southern California and Idaho, where teams of dedicated keepers and scientists continue to struggle to prevent its extinction.
Modern Woes
California condor populations have been declining throughout this century. We don't know all the reasons for this decline, but researchers can certainly point to some of them.
This species has been particularly susceptible to lead and strychnine poisoning. A hunter shoots
a deer. The deer, wounded, runs away and dies. A California condor finds the carcass and, along with the carrion, ingests the lead from the hunter's bullets. A farmer, hoping to cut down on coyote predation on his livestock, puts out a poisoned sheep carcass. A condor gets to it first and ingests the strychnine intended for the coyote. These are common scenarios for many predators and carrion eaters. Pesticides ingested by prey species become concentrated in predators, often with devastating results.
Condor eggs, being large and rare, were once favored by egg collectors. The number of eggs taken by collectors wouldn't seem to be very significantÑbetween 1881 and 1910, for example, collectors took about 50 eggs from condor nestsÑbut the loss of even a small number of eggs had a definite impact on their populations. Condors have a very low reproductive rateÑthey only lay one egg every other year, and don't even begin breeding until they are five to eight years old. Every egg is crucial to the survival of this ancient species, which probably never existed in great numbers.
Another possible contributor to the condor's decline is the diminishing availability of carrionÑtheir food source. Fossil evidence indicates that condors were widely distributed across North America
before human populations dominated the continent. Ten thousand years ago the carcasses of large animals would have been plentiful. A condor's eye view of the U.S. today provides a starkly different picture.
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