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7329 Silverado Trail
Napa, CA 94558
2109 Arch Airport Rd
Stockton, CA 95206
Acting Regional Manager:
Stanislaus River Report
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Stanislaus River Basin and Calaveras River Water Use Program|
Threatened and Endangered Species Report - March 1995
Bay Delta and Special Water Projects Division, CA Dept. of Fish and Game
White-tailed Kite(formerly Black-shouldered Kite)
California Department of Fish and Game "Special Animal"
Life HistoryThe white-tailed kite, formerly known as the black-shouldered kite, is whitish in appearance. It is falcon-shaped with long, pointed wings and a long white tail. It measures 15 to 17 inches in length and has a 42 inch wingspan. The adults are a pale gray with white head, underparts, and tail. Sexes are almost identical in plumage and size but the immatures have a rusty breast, a brown back, and a narrow dark band near the tip of their pale, grayish tail.
The flight of kites is graceful and buoyant; the wings are held with the tips pointed down in a gull fashion. In perched birds, wingtips reach the tail.
Nesting by white-tailed kites in California has been reported for the months February through August with peak activity seen in March, April, and May (Waian 1973). Nesting habitats are best described as oak woodlands or trees along marsh edges. White-tailed kites have been reported to use any suitable tree that is of moderate height, such as eucalyptus, cottonwoods, toyons, and even coyote bush with the nests placed near the tops of these shrubs or trees.
Occasionally, the kite rears two broods per season with each brood ranging from three to six eggs. The female alone incubates the eggs for about 28 days. The young fledge in approximately 35 to 40 days. During the incubation and nestling period, the male is at hand to feed the female and the young.
The preferred prey is almost always diurnal rodents. In many ways the kite exhibits kestrel behavior in that they are known to soar, glide, and hover less than 100 feet above the ground searching for prey items. They slowly descend vertically upon their prey with wings held high, and legs extended; kites rarely dive into tall cover (Thompson 1975).
Outside California, this raptor inhabits a disjunct range extending from Texas, Oregon, Arizona, the gulf coast of Louisiana and Mississippi, Oklahoma, and are rare in Florida. Individuals have wandered far afield and have been recorded in New Mexico, Nevada, Washington, Georgia, the Carolinas, and as far north as Nebraska, Wisconsin, and Minnesota. Within California these kites are common to uncommon yearlong residents in the coastal and valley lowlands. They are rarely found away from agricultural areas and are restricted to lower elevations.
Findings and ConclusionsPopulation numbers of this kite were formerly low but have increased somewhat as available habitat areas have been produced with year-round irrigation of agricultural land.
The white-tailed kite was observed on numerous occasions by CDFG biologists. They were quite common in the area surrounding the lower Stanislaus River, particularly from the town of Oakdale downstream and is known to nest in this area (Reeve pers. comm.).
Because they forage primarily in open areas, their numbers are lower in the riparian areas as compared to the fields near the river. Any projects affecting the riparian corridor or open areas adjacent to the river could impact the species.