Why can woodpeckers damage utility poles and fence posts?

Woodpeckers may damage utility poles and fence posts primarily because these structures are located in open country, well-kept woodlots, or near cultivated forests where natural dead trees—which the birds typically prefer for excavating nesting and roosting holes—are scarce.1

While these birds are highly specialized for wood-pecking, their behavior is driven by the need for suitable sites to create homes. When natural options are unavailable, they turn to man-made wooden structures as alternatives.1