Yellow-bellied Sapsucker

On a walk through the forest you might spot rows of shallow holes in tree bark. In the East, this is the work of the Yellow-bellied Sapsucker, an enterprising woodpecker that laps up the leaking sap and any trapped insects with its specialized, brush-tipped tongue. Attired sharply in barred black-and-white, with a red cap and (in males) throat, they sit still on tree trunks for long intervals while feeding. To find one, listen for their loud mewing calls or stuttered drumming.

The Yellow-bellied Sapsucker makes two kinds of holes in trees to harvest sap. Round holes extend deep in the tree and are not enlarged. The sapsucker inserts its bill into the hole to probe for sap. Rectangular holes are shallower, and must be maintained continually for the sap to flow. The sapsucker licks the sap from these holes, and eats the cambium of the tree too. New holes usually are made in a line with old holes, or in a new line above the old. The sapwells made by Yellow-bellied Sapsuckers attract hummingbirds, which also feed off the sap flowing from the tree. In some parts of Canada, Ruby-throated Hummingbirds rely so much on sapwells that they time their spring migration with the arrival of sapsuckers. Other birds as well as bats and porcupines also visit sapsucker sapwells. Yellow-bellied Sapsuckers have been found drilling sapwells in more than 1,000 species of trees and woody plants, though they have a strong preference for birches and maples. The Yellow-bellied Sapsucker is the only woodpecker in eastern North America that is completely migratory. Although a few individuals remain throughout much of the winter in the southern part of the breeding range, most head farther south, going as far south as Panama. Females tend to migrate farther south than do males.