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Exploring the beautiful nature of California
California Nature: Vultures
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The New World vultures are not closely
related to Old World vultures, but superficially resemble them
because of convergent evolution. Like the Old World vultures,
they are scavengers. However, unlike Old World vultures, which
find carcasses by sight, New World vultures have a good sense of
smell with which they locate carcasses. There are 7 species
world wide, all found only in the Americas, 3 North American
species, and 3 Californian species.
California is home to the turkey vulture, black vulture, and
California Condor. New World vultures
do not build nests. This species lays its eggs in a cave,
between large rocks, at the base of a tree, or in a hollow
stump. The female lays 2 eggs that are incubated by both parents
for 38 - 45 days. The young vultures fledge at about 3 months
old, but stay with the parents in a social group for years.
One-on-one, a Black Vulture can be dominated by the slightly
larger Turkey Vulture. But, Black Vultures rarely travel alone.
Flocks of Black Vultures can quickly take over a carcass and
drive the more solitary Turkey Vultures away.
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The Black Vulture flaps its wings rather
frequently while it soars. It is more social
than the Turkey Vulture, often traveling in
large flocks. Like the Turkey Vulture, the Black
Vulture’s numbers are increasing and its range
is expanding northward in response to global
climate changes. These vultures are found in
lowland areas along rivers or in open habitats
in the southern United States and throughout
Central and South America. They rarely inhabit
dense forests.
The Black Vulture has adapted well to human
habitats and can be seen at garbage dumps,
markets, and fishing docks. Vultures eat carrion
in the form of road-kills or dead cattle in
pastures. Black vultures are more aggressive and
may occasionally kill or injure lambs, calves,
cows giving birth, or other incapacitated
livestock. These birds soar looking for
carcasses or other scavenger activity.
The Black Vulture has a body length of 22 - 27
inches, a wingspan of 4 1/2 - 5 feet, and weighs
between 4-5 pounds. The head and neck are
featherless and the skin is dark gray and
wrinkled. The turkey vulture holds its wings in
a slight "v" while soaring, whereas the black
vulture's wings are held straight. The tail of
the black vulture is usually more fanned out in
flight and is shorter and broader than that of
the turkey vulture.
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The black vulture flaps its wings more and
soars less than its relative. From below it has whitish patches
near the tips of the wings, whereas the wings of the turkey
vulture lack these patches. Black vultures must flap their wings
more often than a Turkey Vulture.
Its only form of vocalization is a grunt or hiss, and typically
nests in caves, hollow trees or on the bare ground. The Black
Vulture’s scientific name comes from korax, the Greek word for
raven; gyps, which means vulture; and from the Latin word
atratus, meaning to be clothed in black, as in mourning. The
common name, Vulture, comes from the Latin vulturus meaning “tearer.”
The black vulture normally stays within its normal range
year-round, but some may migrate short distances in the winter.
A group of vultures has many collective nouns, including a
"cast", "committee", "meal", "vortex", and "wake" of vultures.
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Although it has an ugly, bare-skinned face, the Turkey Vulture
is beautiful on the wing. Seldom does this graceful and talented
bird flap its wings as it soars over large areas searching for
carrion.
The Turkey Vulture uses its sense of smell to locate carrion.
The part of its brain responsible for processing smells is
particularly large, compared to other birds. Its heightened
ability to detect odors allows it to find dead animals below a
forest canopy.
The Turkey Vulture roost in a large group, but usually forages
alone, unlike its smaller, more social relative, the Black
Vulture. Although one Turkey Vulture can dominate a single Black
Vulture at a carcass, usually such a large number of Black
Vultures appear that they can overwhelm a solitary Turkey
Vulture and take most of the food.
The Turkey Vulture is a large bird. It has a wingspan of
67–72 inches, a length of 25–32 inches, and weighs between two
and six pounds. Turkey vultures have dark brown to black
plumage; a featherless, purplish-red head and neck; and a short,
hooked, ivory-colored beak. The adult turkey vulture's head is
small in proportion to its body and is red in color with few to
no feathers. It also has a relatively short, hooked,
ivory-colored beak.
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The irises of the eyes are gray-brown; legs
and feet are pink-skinned, although typically stained white. The
turkey vulture's eye has a single incomplete row of eyelashes on
the upper lid and two rows on the lower lid.
Its life expectancy in the wild ranges upward of 16 years, with
a captive life span of over 20 years being possible.
The breeding season of the Turkey Vulture commences in March,
peaks in April to May, and continues into June. Courtship
rituals of the Turkey Vulture involve several individuals
gathering in a circle, where they perform hopping movements
around the perimeter of the circle with wings partially spread.
In the air, one bird closely follows another while flapping and
diving. Eggs are generally laid in the nesting site in a
protected location such as a cliff, a cave, a rock crevice, a
burrow, inside a hollow tree, or in a thicket. There is little
or no construction of a nest; eggs are laid on a bare surface.
Females generally lay two eggs, but sometimes one and rarely
three. The eggs are cream-colored, with brown or lavender spots
around their larger end. Both parents incubate, and the young
hatch after 30 to 40 days. Chicks are helpless at birth. Both
adults feed the chicks by regurgitating food for them, and care
for them for 10 to 11 weeks.
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Blackbirds
California Condor
Cardinals
Cranes
Crows, Jays,
& Magpies
Eagles
Finches
Flycatchers
Hawks
Hummingbirds
Owls
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Raptors
Shore Birds
Sparrows
Tanager
Thrushes
Vultures
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Warblers
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Wrens |
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