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Most of the birds breeding in Canada and the northern United States migrate south in the winter, although some males stay as year-round residents. It is a very rare vagrant to western Europe. The American Kestrel is the smallest falcon in North America – about the size of a large thrush, such as the American Robin (Turdus migratorius), on average. The American Kestrel is sexually dimorphic, although there is some overlap within the species. The female ranges in length from 9-11 in (23-28 cm) with a wingspan of 21-24 in (53-61 cm) and weighs an average of 4.2 oz (120 g). The length of the male varies between 8-10 in (20-25 cm) with a wingspan ranging from 20-22 in (51-56 cm) and weighing an average of 3,9 oz (111 g). These subtle differences are often difficult to discern in the field.
The coloration of the feathers, however, greatly varies between the sexes. Males have blue-grey secondary feathers on their wings, while the undersides are white with black barring. The back is rufous in coloration, with barring on the lower half. The belly and flanks are white with black spotting. The tail is also rufous, except for the outer rectrix set, which is white with a black subterminal band. The back of the female American Kestrel is rufous with dark brown barring. The wings exhibit similar coloration and patterning to the back. The undersides of the females are white with rufous streaking. The tail of the female is noticeably different from the male, being rufous in color with numerous narrow dark brown or black bars. Juveniles exhibit coloration patterns similar to the adults.
The coloration of the feathers, however, greatly varies between the sexes. Males have blue-grey secondary feathers on their wings, while the undersides are white with black barring. The back is rufous in coloration, with barring on the lower half. The belly and flanks are white with black spotting. The tail is also rufous, except for the outer rectrix set, which is white with a black subterminal band. The back of the female American Kestrel is rufous with dark brown barring. The wings exhibit similar coloration and patterning to the back. The undersides of the females are white with rufous streaking. The tail of the female is noticeably different from the male, being rufous in color with numerous narrow dark brown or black bars. Juveniles exhibit coloration patterns similar to the adults.
Glad this arrived OK! It's funny that you like roses and tulips but chose to write about the falcon; there's a lot of information I didn't know. :)
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