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Swainson's Hawk
Pan & Taka
Pan, (left, whose size suggests a female) was
stolen as an egg in 1997 from a nest in Colorado. She was raised illegally
and ultimately confiscated in Texas. A human imprint, she is not releasable
and was transferred to CRC in June 1999.
Taka - is assumed to be male based on size. As an adult, he was brought into UC
Davis Veterinary School's raptor center in September 2001 with an open
fracture of the right wrist and possible pelvic fracture, having been found by a citizen
alongside a road. Though originally thought hit by car, x-rays revealed
that he had been shot. His wing did not heal with sufficient extension to
enable him to fly well enough for hunting or migration.
He was transferred to CRC in April 2003 from another education program in California. 'Taka' is
Japanese for Hawk. The Japanese symbol means 'hawk'.
Swainson's Hawk (Buteo swainsoni)
This is a large, slender hawk of the western plains. The Swainson's Hawk is
close in size and shape to the more common Red-tailed Hawk, but has longer,
narrower, more pointed wings, and a smaller bill and feet. Three subgroups
have been defined by color, and the light form is the most common. These
birds have a dark brown head with brown eyes, and dark brown upper parts. A
wide brown band on the chest contrasts with a white throat and pale belly.
The underside of the wings show white wing linings, contrasting with darkly
barred flight feathers, and even darker trailing edges; the tail is gray
with many narrow bands, and one wide dark band near the tip. The rufous form
of this hawk has a reddish belly, and the dark form is dark overall, with a
dark throat - these two subgroups account for less than 10% of the total.
Notes
Size - Length: 17 - 22" • Wing Span: 47 - 54" • Weight: 1.3 - 2.7 lb.
Status - State and federally protected. A species of concern,
recent sharp population declines led to satellite telemetry projects and
confirmation of huge die-offs due to use of the pesticide monocrotophos on
the wintering grounds in Las Pampas, Argentina (where they are known as the
'grasshopper hawk' due to the huge number of grasshoppers they eat).
Assistance from Canada and the US has led to the banning of the pesticide
and an extensive educational effort for farmers to find effective
alternatives less harmful to human and avian health.
Habitat - Open country of the western US and Canada for breeding,
from low to moderate elevations. Prairies, rangelands, meadows, any open
areas with scattered trees -- such places will be attractive to this
species. Cultivated lands attract this hawk in some areas, where the human
disturbance of agriculture causes concentrations of insects and rodents.
Diet - Rodents and other small mammals form the bulk of the diet
during breeding season; insects are an important part of the diet at other
times of the year, especially crickets and grasshoppers. These hawks also
take some reptiles and amphibians, and are even attracted to swarms of bats.
Depending on the type of prey, they will perch hunt, or hunt on the wing.
Call - The Swainson's Hawk is usually quiet outside of nesting
season. The typical call is a shrill, plaintive kr-e-e-e-e-e-e-e.
Nesting - Build a stick nest as high as possible on a cliff, bluff,
or rock outcrop, or in a lone tree. They often return to the same nest each
year, which can be up to 3 or 4 feet across.
Most Common Problems - Collision with vehicles is the most common
problem here. While migrating in large, insect-seeking flocks through
Central and South America, this hawk is very susceptible to mass poisonings
from insecticides.
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