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Exploring the beautiful nature of California
California Nature: Hawks
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Hawks are carnivores (meat eaters) that
belong to the category of birds known as raptors, birds of prey.
They have strong, hooked beaks; their feet have three toes
pointed forward and one turned back; and their claws, or talons,
are long, curved and very sharp. Prey is killed with the long
talons and, if it is too large to swallow whole, it is torn to
bite-sized pieces.
Based on general body shape and flight habits, hawks are classified into different groups: the most common being the Accipiters and the Buteos.
The Sharp-shinned Hawk, the Cooper's Hawk and the Goshawk are Accipiters. They have long tails and short, rounded wings that enable them to dart through and around trees in pursuit of other birds, their principal prey. Typically, they fly low with a series of rapid wing beats followed by a brief period of sailing, then another series of wing beats. Accipiters are associated with brush and timbered areas.
The Buteos are the largest of the hawks. They are the broad-winged, broad-tailed soaring hawks that are more readily seen because of their habit of circling high in the air or perching in dead trees or on telephone poles along the road. They include the Red-tailed, the Red-shouldered, the Swainson's, the Rough-legged and the Ferruginous hawks. |
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The red-tailed hawk is the most common member of
the genus Buteo found in the U.S. An
opportunistic feeder, this hawk will take almost
anything as prey but it is most successful in
pursuit of rodents. In fact rodents make up
about 85% of their diet. Although common in many
areas, the red-tailed hawk is declining in many
areas due to habitat loss, egg shell thinning
due to pesticides and especially due to conflict
with humans.
The Red-tailed hawk ranges throughout North
America to central Alaska and northern Canada,
and south as far as the mountains of Panama.
Although not truly migratory, they do adjust
seasonally to areas of the most areas of the
most abundant prey. Red-tailed hawks are known
for their brick-colored tails, but there are 14
subspecies of various colorations, and not all
of them have this characteristic.
These birds of prey are also known as buzzard
hawks and red hawks. Red tailed hawks are
keen-eyed and efficient hunters. Red-tails
prefer open areas, such as fields or deserts,
with high perching places nearby from which they
can watch for prey. But these birds are
adaptable and also dwell in mountains and
tropical rain forests. Hawks have even embraced
human habitats.
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The Red tailed hawk often perches on
telephone poles and takes advantage of the open spaces along the
roadside to spot and seize mice, ground squirrels, rabbits,
reptiles, or other prey. Red-tailed hawks are monogamous and may
mate for life. They make stick nests high above the ground, in
which the female lays one to five eggs each year. Both sexes
incubate the eggs for four to five weeks, and feed the young
from the time they hatch until they leave the nest about six
weeks later.
Red Shouldered Hawks are found in moist open forests,
bottomlands and other wet lands throughout most of California.
It is perhaps the most vocal American hawk. The hawk eats a
variety of prey including small mammals, birds, frogs, snakes,
lizards, snails and insects. The Red-shouldered Hawk is divided
into five subspecies. The four eastern forms contact each other,
but the West Coast form is separated from the eastern forms by
1600 km (1000 mi). The northern form is the largest. Although
the American Crow often mobs the Red-shouldered Hawk, sometimes
the relationship is not so one-sided. They may chase each other
and try to steal food from each other. They may also both attack
a Great Horned Owl and join forces to chase the owl out of the
hawk's territory.
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Sharp-shinned hawks can be found throughout much of North
America, including Mexico. In South America, they are found from
Venezuela to northern Argentina. Most of the North American
populations migrate to the southern parts of their range in
winter. Sharp-shinned hawks are forest birds. They are found in
pine, fir and aspen forests (among others). They can be found
hunting in forest interior and edges from sea level to near
alpine areas.
Sharp-shinned hawks can also be found near rural, suburban and
agricultural areas, where they often hunt at bird feeders.
Sharp-shinned hawks are the smallest hawks in North America.
Males are 24 to 27 cm long and weigh 87 to 114 g. Females are
larger, measuring 29 to 34 cm in length and weighing 150 to 218
g. Males have a wingspan of 53 to 56 cm and females 58 to 65 cm.
Sharp-shinned hawks have bluish-gray to slate colored
upperparts, with darker coloration on the crown. Their
underparts are white with brown bars and their short, rounded
wings are dark above and light below. Females have fewer bars on
the breast, and their upper parts are more brownish.
Sharp-shinned hawks have a short, dark colored, hooked beak and
yellow legs and feet. Their tail is square-tipped when not
spread and has three to five dark stripes with a small white
stripe on the tip.
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The Harris Hawk, formerly known as the Bay-winged Hawk or Dusky Hawk, is a medium-large bird of prey which breeds from the southwestern United States south to Chile and central Argentina. Birds are sometimes reported at large in Western Europe, especially Britain, but it is a popular species in falconry and these records almost certainly all refer to escapes from captivity.
The diet consists of small creatures including birds, lizards, mammals, and large insects. Because it will hunt in groups, the Harris's Hawk can also take down larger prey, such as jackrabbits.
While most raptors are solitary, only coming together for
breeding and migration, Harris's Hawks will hunt in cooperative
groups of two to six. This is believed to be an adaptation to
the desert climate in which they live. In one hunting technique,
a small group flies ahead and scouts, then another group member
flies ahead and scouts, and this continues until prey is bagged
and shared. In another, all the hawks spread around the prey and
one individual flushes it. |
| Blackbirds
California Condor
Cardinals
Cranes
Crows, Jays,
& Magpies Eagles
Finches
Flycatchers
Hawks
Hummingbirds
Owls Game Birds
Raptors
Shore Birds
Sparrows
Tanager
Thrushes
Vultures
Wading Birds Warblers
Woodpeckers
Wrens |
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