There is a common problem that those birds that bang their heads against the trees to make holes (Can't remember their name) make holes in irrigation pipes on farmer's fields (made out of plastic).
The question is why? Can't the birds tell between a pipe and a tree?
This is correct, wood peckers listen to the tree and can hear the bugs under the bark so then they peck at the tree to get the bugs out, my only explaination for the pipes is that the water rushing sounds like bugs crawling....