Monday, October 4, 2010

Red-shouldered Hawk

The red-shouldered hawk is a slim, narrow-winged, long-tailed buteo. It obtains prey by still-hunting from perches and scanning the ground below. The 17- 24 inch (43-61 cm) adult is blackish-brown above with extensive black and white checkering, especially apparent on the wings. Rufous streaking and edging is apparent all over the body, but is most evident on the shoulders. The tail is blackish with three or four narrow white bands. The breast, belly and wing linings are rufous with black streaks. Immatures are brownish above with little or no rufous coloring. Their undersides are cream-colored, heavily streaked, and blotched with dark brown. The tail is brownish-gray with narrow, light bands. From courtship to the start of incubation red-shouldered hawks scream a loud "kee-yar;" during the remainder of the year they are predominantly silent.

Life History:
During the courtship display, one to four birds may soar together. They flap, swoop and descend while calling before diving to the original perch. They may rise in wide spirals 1,500 to 2,000 feet above the nest. The male and female build a nest together. It is usually placed in the crotch of the main trunk of a tree, 20-60 feet high. It is made of sticks and twigs, lined with strips of inner bark, fine twigs, dry leaves, evergreen sprigs, feathers and down. The clutch averages three eggs. Incubation lasts for 33 days and the young fledge in 39-45 days. First breeding usually occurs at two years of age.

Distribution and Habitat:
Red-shouldered hawks breed east of the Great Plains from southern Canada to the Gulf Coast, west along the Gulf to central Mexico. An isolated population breeds in California. Wintering occurs south of Canada, though sparsely so in the northern states. In New York, nesting populations were found in the Appalachian Plateau, Catskill Peaks, the Delaware, Mongaup and Rensselaer hills, the Tug Hill Plateau, and Lake Champlain Valley.
This raptor breeds in moist woodlands, riverine forests, the borders of swamps, open pine woods and similar habitats. Nesting almost always occurs near water, such as a swamp, river or pond.

This hawk was once the most common large hawk of central and western New York. However, in recent years New York populations have declined. Biologists have found it difficult to determine if the change in historic data represents a shift in the breeding range or an actual population decline. The primary problem facing this species is loss of habitat. Since European settlement in the 17th century and especially since the 19th century, the favored closed canopy forests have been cut for logging, agriculture, and urban and suburban development.

Disturbances from humans in the form of off-road vehicles, hunters, horseback riders and suburbanites in general have pushed red-shouldered hawks into the deepest, wildest areas left. Although some members of this species seem to be unaffected by humans, most are secretive and avoid inhabited areas. In 1999, the red-shouldered hawk was down graded from "Threatened" to "Special Concern."

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