About Tyrannus vociferans Swainson, 1826
Adults of this species have a gray head with slightly darker cheeks, a dark, unforked tail with a buffy fringe, and gray-olive colored underparts. They have a pale throat and a deep yellow lower breast. Juveniles have duller overall plumage, with pale edges along their wings. This species measures 8.3 to 9.1 inches (21 to 23 cm) in length, weighs an average of 1.6 oz (45 g), and has a wingspan of 41 cm. In summer, these birds live in California, and the eastern Rocky Mountain region stretching from Montana to Utah. Their preferred habitat consists of rangelands and savannas. This species is migratory: they travel to winter grounds between Southern California and northern Central America. There is a permanent resident population in south-central Mexico. The 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.
