Sapsucker Sucking

Sapsuckers are famous for drilling holes in trees and then feeding on the sap that flows into the cavities. Yellow-bellied Sapsuckers maintain these holes daily to keep the sap flowing. They defend their wells against other birds—Yellow-rumped Warblers, hummingbirds, other sapsuckers—that may wish to share the sap. Breeding sapsuckers also take various arthropods, but often dip their prey in sap to add to the nutritional value.

This female Yellow-bellied Sapsucker, photographed in late April in Northfield, fed on a maple—but the woodpecker is known to drill into about 100 species of woody plants. In the spring, wells are drilled in xylem, to capture upward flowing sap. Later the birds drill into phloem for downward moving sap. If you look closely, you can see a few wells drilled to the right of this sapsucker. Often sapsucker trees look like they have been machine-gunned by sap wells.

The photo, by the way, was taken on a snowy day and the background is not photoshopped to produce the white background.