Passage: It is the smallest of the kestrels, 18–23 cm long with a wingspan of 40–45 cm. The wings are fairly short and rounded. The adult male's upperparts are reddish brown with black spots while the underparts are unspotted and buff. The head and rump are dark blue-grey. The tail is blue-grey with black bars. The bill is dark and the feet and cere are yellow. Females are similar to the males in appearance but are a little larger and paler. Immature birds have a brown, streaked head, spots on the breast and a buff tip to the tail.

Question: What variation of brown is the adult male's upperparts?
reddish