The very large holes left in this yellow birch are characteristic of the pileated woodpecker, Dryocopus pileatus. Maine, 28th November 2008, mixed coastal forest. The identification by Bob Andersen (thanks Bob) is tentative and I would welcome confirmation or correction
The Red-crowned Woodpecker ranges from Costa Rica to Venezuela, and is known locally as Carpintero Habado. Photo is from near Summit Park in the Panama Canal Zone.
The Acorn Woodpecker is found from California to Colombia, wherever there are acorns. A female on left, and a pair storing acorns in a tree on right. Known as Carpentero Bellotero in Latin America. Photos from California.