Yellow Bellied Sapsucker

Sapsuckers attack only living trees. The adult birds cause damage by pecking horizontal rows of regularly spaced, small, oval to squarish holes through the bark to the sapwood. Unlike other woodpeckers, sapsuckers do not drill these holes in search of grubs or worms on which to feed. Instead, the birds use their short brushlike tongues to drink the sap that oozes into the holes. Damage varies considerably, depending on the persistence of attack. Lightly attacked trees usually make a complete recovery. Control is difficult because the yellow-bellied sapsucker, like most other birds, is protected under the Migratory Birds Convention Act, and may not be killed or captured, or its eggs destroyed. 

More information:
Damage and control of Yellow Bellied Sapsucker