- Sphyrapicus thyroideus
Iridescent black head, back, sides and tail, white stripe behind the eye and a lower white stripe across each side of the head, red chin, bright yellow belly, black wings with large white patches. The female is completely different - black, pale yellow breast, brownish head with black streaking and fine barring on the back, breast and sides.
Two subspecies are recognized:
- S.t. thyroideus - southern British Columbia mountains to northern Baja; winters to northern Mexico
- S.t. nataliae - southeastern British Columbia to the Rocky Mountains and Great Basin ranges of the USA.
Open forested areas, including conifers.
- Breeding: They excavate a new nesting cavity each year, sometimes reusing the same tree.
- Diet: Includes sap, mainly from conifers; insects are the main food source during the nesting season; berries are eaten outside of the breeding period.
- Clements, J. F., T. S. Schulenberg, M. J. Iliff, D. Roberson, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2016. The eBird/Clements checklist of birds of the world: v2016, with updates to August 2016. Downloaded from http://www.birds.cornell.edu/clementschecklist/download/
- BirdForum Opus contributors. (2023) Williamson's Sapsucker. In: BirdForum, the forum for wild birds and birding. Retrieved 4 December 2023 from https://www.birdforum.net/opus/Williamson%27s_Sapsucker