Brewer's sparrow (Spizella breweri) is a small, slim species of American sparrow in the family Emberizidae. This bird was named after the ornithologist Thomas Mayo Brewer. Adults have grey-brown backs and speckled brown crowns, both with dark streaks, and a pale eye-ring. Their wings are brown with light wing bars and the underparts are pale grey. Their bill is pale with a dark tip and they have a long notched tail. They are 5.1-5.9 inches in length. The COSA lies within the Brewer Sparrow's breeding range but has so far only been spotted infrequently in April, May, August, and September