Their young have brown heads that don't turn red until their first winter. Creosote-coated utility poles are lethal to eggs and young reared in them. In winter, some individuals will migrate southward to areas where there is an abundance of acorns, which they often seal in cavities with splinters of wood. This species is declining significantly in parts of its range. Sapsuckers have white rumps and white patches on their shoulders.
Males have a red throat that females lack.
These woodpeckers have an odd habit of drilling tiny holes in tree bark in neatly spaced rows, and then returning to them to feed on the sap that oozes out or on insects attracted to the sap. They guard sap wells from other birds, squirrels and chipmunks by swooping and squawking at them. Sapsucker sap wells provide a food source for migrating hummingbirds. They drill wells and eat sap from 246 native tree species. The young learn sapsucking by observing their parents once they leave the nest.