Western Bird Guide: Birds of the Rockies and West to the Pacific

by Charles K. Reed

WILLIAMSON SAPSUCKER.

404. Sphyrapicus thyroideus. 9 inches.

A great variation in the plumage of this oddly marked bird is found. The male is mostly black on the back and breast, with a white rump, and with only a narrow patch of red on the throat; the under parts are bright yellow. The female is entirely different, being brownish in place of the black on the male, has no red on the throat, and on the back is barred with black and white.

Their nesting habits are the same as those of the family previously mentioned. Four to seven white eggs (.97 × .67).