Yellow-bellied Sapsucker (Sphyrapicus varius)
Drumming: The cadence of the Yellow-bellied's drumming is very distinctive and easily recognized.
It starts out relatively fast and then winds down in an irregular, stuttering manner. the later strikes often taking the form of rapid couplets (Walters et al. 2002).
Yellow-bellied Sapsucker drumming, June 7, 2010. Wyalusing State Park, Wisconsin. You can hear a second sapsucker respond in the distance.
Walters, Eric L., Edward H. Miller and Peter E. Lowther. 2002. Yellow-bellied Sapsucker (Sphyrapicus varius), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/662 doi:10.2173/bna.662