The
California Condor is one of the largest, and rarest, of North American
Birds. Numbers of California Condors began declining after settlement
of the West began in the 1800s. By 1987, only 22 birds were left, and
all 22 birds were captured and brought into captivity in hope to breed and
increase the population. Captive-bred birds began to be released into
the wild in 1991, with releases continuing to this day. As of 2012,
there were approximately 400 California Condors, with about half in
captivity and half in the wild.
The original causes of the decline of the species were many and varied.
Poaching and shooting of the birds undoubtedly caused some of the
initial decline. Ranchers in the West saw the massive birds
feeding on dead cattle, and often assumed the Condors themselves were
responsible for the death of livestock. They were thus persecuted
for their supposed potential negative impacts on lifestock operations.
A significant cause of mortality has also been the ingestion of lead
ammunition from dead animals. Animals killed with lead
pellets or bullets are preyed upon by California Condors, and the
unusually strong and effective digestive system of the species results
in the intake of large amounts of lead. Lead poisoning has
undoubtedly led to the death of many California Condors over the last
century, and continues to be an issue for the small remaining wild
population.
Releases of captive bred birds continues, with releases in Arizona (near
the Grand Canyon) and central California. Captive bred
California Condors have bred and successfully raised young in the wild,
but breeding success in the wild remains frustratingly low, and the
small
wild population is still primarily maintained through the release of
captive-bred birds.
Habitat: California Condors were once found in
much of the Western United States. In general, they are found in areas
with large open habitats with foraging opportunities, but with cliffs or
large trees nearby for nesting.
Diet: Feeds on carrion. Historically, prior
to settlement of the West, they fed on the carcasses of large animals, with
food items dependent upon location and availability. Inland, large
animal carcasses such as deer, elk, bears, or other large animals are
consumed, although smaller animals down to the size of rabbits are also
consumed. In coastal areas, Condor populations often specialized on
aquatic mammal carcasses, with whale or seal carcasses often providing a
source of food.
Behavior: California Condors lack a sense of smell
and hunt by sight. Carrion is spotted by soaring and looking for carcasses.
Foraging is usually done during the warmer parts of the day, when rising
thermals aid the flight of the large birds.
Nesting: The California Condor usually builds a
nest in a cave or protected shelf on a cliff face. They also
historically used very large cavities in large trees, such as the top of a
broken-off large evergreen tree. The nest itself is typically only a
loose collections of a few stones and pebbles. Both the males and
females incubate the eggs, with incubation last nearly 2 months. Upon
hatching, both parents will forage for food and feed the young. Given
the long incubation period and the relatively long period of time before the
young leave the care of their parents, California Condors are only able to
nest every other year. The very slow rate of reproduction has frustrated
efforts to quickly raise wild populations of the species.
Song: California Condors are generally silent.
The only noises produced are occasional hissing and grunting sounds.
Migration: Considered a permanent resident
throughout their range, but individual birds sometimes do move fairly long
distances in search of foraging opportunities.
Similar Species:
Unlikely to be mistaken for another species.
Conservation Status: The
IUCN
currently lists the California Condor as critical endangered. They
remain one of the rarest birds in the world, with only a few hundred alive,
with about half in captivity and half in the wild.
Photo Information: October 18th, 2003 - Bitter
Creek National Wildlife Refuge - U.S. Fish and Wildlife Service photo -
Photo licensed through
Creative
Commons 2.0 Generic license.