The
spectacular but endangered California Condor is the largest bird
in North America. These superb gliders travel widely to feed on
carcasses of deer, pigs, cattle, sea lions, whales, and other animals.
Pairs nest in caves high on cliff faces. The population fell to
just 22 birds in the 1980s, but there are now some 230 free-flying
birds in California, Arizona, and Baja California with another 160
in captivity. Lead poisoning remains a severe threat to their long-term
prospects.
At a Glance
Habitat
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Food
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Nesting
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Behavior
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Conservation
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Mountains
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Carrion
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Cliff
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Soaring
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Critically Endangered
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Measurements
Both Sexes
Length
46.152.8
in
117134
cm
Wingspan
109.1 in
277 cm
Weight
246.9349.2
oz
70009900
g
Relative Size
Larger than
a Bald Eagle; this is the
largest bird in North America.
Other Names
Condor de Californie (French)
Condor californiano, Buitre (Spanish)
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Cool Facts
- Whats in a name? The name condor comes
from cuntur, which originated from the Inca name for the Andean
Condor. Their scientific name, Gymnogyps californianus, comes
from the Greek words gymnos, meaning naked, and refers to the
head, and gyps meaning vulture; californianus is Latin and refers
to the birds range.
- In the late Pleistocene, about 40,000 years ago, California
Condors were found throughout North America. At this time, giant
mammals roamed the continent, offering condors a reliable food
supply. When Lewis and Clark explored the Pacific Northwest in
1805 they found condors there. Until the 1930s, they occurred
in the mountains of Baja California.
- One reason California Condor recovery has been slow is their
extremely slow reproduction rate. Female condors lay only one
egg per nesting attempt, and they dont always nest every
year. The young depend on their parents for more than 12 months,
and take 6-8 years to reach maturity.
- Condors soar slowly and stably. They average about 30 mph
in flight and can get up to over 40 mph. They take about 16 seconds
to complete a circle in soaring flight. By comparison, Bald Eagles
and Golden Eagles normally circle in 1214 seconds, and Red-tailed
Hawks circle in about 810 seconds.
- At carcasses, California Condors dominate other scavengers.
The exception is when a Golden Eagle is present. Although the
condor weighs about twice as much as an eagle, the superior talons
of the eagle command respect.
- Condors can survive 12 weeks without eating. When they
find a carcass they eat their fill, storing up to 3 pounds of
meat in their crop (a part of the esophagus) before they leave.
- California Condors once foraged on offshore islands, visiting
mammal and seabird colonies to eat carrion, eggs and possibly
live prey such as nestlings.
- In cold weather, condors raise their neck feathers to keep
warm. In hot weather, condors (and other vultures) urinate onto
a leg. As the waste evaporates, it cools off blood circulating
in the leg, lowering the whole body temperature. Condors bathe
frequently and this helps avoid buildup of wastes on the legs.
- Adult condors sometimes temporarily restrain an overenthusiastic
nestling by placing a foot on its neck and clamping it to the
floor. This forceful approach is also a common way for an adult
to remove a nestlings bill from its throat at the end of
a feeding.
- Young may take months to perfect flight and landings. Crash
landings have been observed in young four months after their first
flight.
- California Condors can probably live to be 60 or more years
oldalthough none of the condors now alive are older than
40 yet.
California Condors have been reintroduced to mountains of
southern and central California, Arizona, Utah, and Baja California.
Nesting habitats range from scrubby chaparral to forested mountain
regions up to about 6,000 feet elevation. Foraging areas are
in open grasslands and can be far from primary nesting sites,
requiring substantial daily commutes. Condors glide and soar
when foraging, so they depend on reliable air movements and
terrain that enables extended soaring flight. They are so heavy
that they can have trouble taking off, so they often use open,
windy areas where they can run downhill or launch themselves
from a cliff edge or exposed branch to get airborne. Before
captive breeding programs began in the 1980s all remaining condors
foraged in an area encompassing about 2,700 square miles; this
range is now expanding as the wild population grows. Young condors
learn the full extent of their range partly from other more
experienced birds. |
California Condors eat carrion of land and marine mammals
such as deer, cattle, pigs, rabbits, sea lions, and whales.
They swallow bone chips and marine shells to meet their calcium
needs. They favor small to medium-sized carcasses, probably
because smaller bones are easily consumed and digested. Condors
locate carcasses with their keen eyesight (not by smell) by
observing other scavengers assembled at a carcass. Once they
land they take over the carcass from smaller species, but they
are tolerant of each other and usually feed in groups. Condors
are wary of humans while feeding, which is probably why they
do not use roadkill as a food source. In captivity, condors
consume 57 percent of their body mass per day to maintain
their weight, but because their crop (an enlarged part of the
esophagus) can hold 3 pounds of food, they may only have to
eat every 23 days. Young are fed by regurgitation. |
Nesting Facts
Clutch Size
1 eggs
Number of Broods
1 broods
Egg Length
3.64.7
in
9.212
cm
Egg Width
2.42.7
in
6.26.8
cm
Incubation Period
5360
days
Nestling Period
163180
days
Egg Description
Pale blue-green
bleaching to white
or creamy.
Condition at Hatching
Helpless,
covered in white down
with eyes open.
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Nesting
Condors lay their eggs directly on the dirt floor of a cliff
ledge or cave, or they construct loose piles of debris from whatever
is available at the nest site, such as gravel, leaves, bark, and
bones. Nests have loosely defined boundaries and are usually about
3 feet across and up to 8 inches deep.
Condors nest mainly in natural cavities or caves in cliffs,
though
they sometimes also use trees, such as coast redwood and, historically,
the giant sequoia. (As the wild population grows, there is the
possibility they may return to the sequoia groves in the Sierra
Nevada.) Condors have multiple nesting sites and may switch
sites between years. Females make the final decision on which
nest location to use. |
California Condors can cover hundreds of miles in one flight
as they soar for hours at a time, looking for carrion. These
long-distance travelers pair off during the breeding season
but are highly social at roosting, bathing, and feeding sites;
individuals recognize one another. Generally, condors are not
aggressive towards each other, though dominant birds will threaten
opponents by standing erect, inflating air sacs in the head
and neck, opening the bill and eventually lunging toward the
opponent. Pairs are monogamous. They share nesting duties nearly
equally, stay together throughout the year, and usually endure
until one member dies. Courtship involves coordinated pair flights,
mutual preening, and displays. Young are dependent on their
parents for at least 6 months after fledging; consequently most
condors do not nest in successive years. Condors bathe frequently;
mates and chicks help groom each others feathers and skin.
They clean up after feeding by rubbing the head and neck on
a nearby rock or other surface. Condors sun themselves, which
helps dry feathers prior to flight and helps the bird warm up.
Condors roost together on horizontal limbs of tall trees, on
ledges, or in cliff potholes. Sleeping condors sometimes lie
prone on their perch with their heads tucked behind their shoulder
blades. Given their size, condors are not normally hunted by
other animals, except humans and occasionally Golden Eagles;
however, nestlings and eggs are at risk of predation from Common
Ravens, Golden Eagles, and black bears. Young condors play,
especially as late-stage nestlings, mock-capturing all sorts
of objects and vegetation, and leaping about in seeming exuberance. |
Conservation
status via IUCN
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Critically Endangered
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California Condors are critically endangered. All of the
more than 400 condors now alive are descended from 27 birds
that were brought into captivity in 1987, in a controversial
but successful captive breeding program. As of 2013, there were
more than 230 individuals in the wild in California, Arizona,
and Baja California. The number has been rising steadily each
year, as captive-bred birds are released and wild pairs fledge
young from their own nests. More than 160 additional condors
live in captivity at breeding programs at The Peregrine Fund,
Los Angeles Zoo, and San Diego Zoo. Condors have benefited greatly
from the Endangered Species Act and from aggressive efforts
to breed them in captivity and re-release them into the wild,
but the survival of the species is still dependent on human
intervention. The major threat is lead poisoning, caused by
ammunition fragments in carcasses they eat. Historically, reasons
for their decline also included accidental poisoning from lead
and from strychnine-laced carcasses left out for coyote control
programs. Hunting by humans also had a substantial effect on
condor populations. Condor recovery has been slow because of
their slow reproductive rate: they produce only 1 egg every
12 years and do not achieve sexual maturity until age
6-8 years. Wild birds are still supplied with clean (lead-free)
carcasses, but they also feed on their own, sometimes on lead-contaminated
carcasses that can result in their deaths. To alleviate the
lead-poisoning problem, workers catch each condor twice per
year to test their blood lead levels; birds that test high are
treated to remove the lead through a technique called chelation.
In 2010 the Peregrine Fund reported that 72 percent of condors
tested in the Vermilion Cliffs, Arizona, showed lead in the
blood, and 34 condors had to be treated. The only route to self-sustaining
wild populations will be by solving the lead-poisoning problem.
Promising first steps have been taken, including a 2008 ban
on lead ammunition used for hunting in the condors California
range, and an innovative voluntary program in Arizona. |
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