
Appearance
Adults have a gray head with slightly darker cheeks; a dark unforked tail with a buffy fringe and gray-olive underparts. They have a pale throat and deep yellow lower breast.Juveniles are duller and have pale edges on their wings.

Naming
Cassin's kingbird and the western kingbird are similar in appearance. Cassin's is a little larger than the western and the upper parts are a darker gray than the western. The most distinctive difference between the birds is that the Cassin's has a thin white strip along lower edge of the tail feathers and the western has a thin white strip that runs along the edge of the tail feathers. This difference can be seen in the image on the left.Distribution
In the summer, these birds can be found in California and from Montana to Utah, along the eastern Rocky Mountains. Their habitat includes rangelands and savannas.These birds migrate to their winter quarters between Southern California and northern Central America. They are permanent residents in south-central Mexico, and their main wintering ranges are west of the Gulf of California on Baja California Sur, and east of the sea on the mainland of western Mexico.
Behavior
They build a bulky nest on a horizontal tree limb in mid-story or the canopy of trees. The three to five spotted white eggs have an incubation period of 18 to 19 days.The Cassin's kingbird primarily feeds on insects it preys upon from high perches by hawking. It also eats berries and fruits in lesser quantities.
The call is a high-pitched shorter followed by a longer chirp, sounding like ''chi-beer''.
Habitat
In the summer, these birds can be found in California and from Montana to Utah, along the eastern Rocky Mountains. Their habitat includes rangelands and savannas.These birds migrate to their winter quarters between Southern California and northern Central America. They are permanent residents in south-central Mexico, and their main wintering ranges are west of the Gulf of California on Baja California Sur, and east of the sea on the mainland of western Mexico.
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