They migrate a good two or three weeks before hummingbirds do. They often rest for a week or two here and there between their winter and summer homes, making temporary feeding stations along the way. Sapsuckers spend much of their time drilling holes, usually going back and forth working on two or three different tree branches at a time. While sapsuckers are guarding and feeding at one set of holes, a host of other birds may visit their other sets of holes. At least 35 species of birds including hummingbirds, warblers, kinglets, and phoebes are attracted to sapsucker borings for sap and insects.
Sapsuckers only drill holes during the spring and summer, while sap is running.
As sap dwindles, the sapsuckers turn to flying insects, ants, fruits, and nuts for food. Ruby-throated Hummingbirds have been seen actually following sapsuckers as these woodpeckers visit their sap trees. As long ago as 1891, a scientist named Frank Bolles noticed that hummingbirds visit sapsucker holes more than any other birds. He saw them come to these holes throughout the summer, but especially in early spring. Experts who have analyzed sap say it is remarkably like flower nectar.