The following is excerpted from the booklet "Woodpecker Damage: A Simple Solution to a Common Problem", listed at the left.
There have been 16 species of woodpeckers recorded in Texas, including the Ivory-billed that is probably extinct. The group includes woodpeckers, flickers, and sapsuckers. Several of these species occur in urban settings and have become a problem by making holes in man-made structures. The main culprits in Texas are Pileated and Red-bellied woodpeckers, and the Northern Flicker. Problems can arise in places you wouldn't normally expect them, like heavily wooded areas where these birds appear to have an adequate supply of trees and snags (standing dead trees). These birds are simply searching for a place to call home and you can help provide them with such a place.
Woodpeckers hammer or peck on wood or metal for three distinct reasons. The first has to do with foraging, and is the most commonly (yet incorrectly) used explanation for all the noise and damage created. The second reason for hammering is called drumming whereby the male announces his claim to a territory by tapping in rapid succession on resonating wood or metal. This is usually done before or during the breeding season, usually February through July, and serves a similar function as singing in songbirds. Drumming is loud, but it is typically short-lived and shouldn't be considered as an endless or destructive problem. The third form of hammering is destructive - and the word "nuisance" fits into the equation. It is called excavating (or chiseling) whereby either males or females construct a nest or roost hole with a chamber typically in trees. This is the most common cause of damage. The cavity produced is an upside down L-shaped chamber with an entrance tunnel that angles down at 90 degrees to the chamber where the bird sleeps or rears its young. Unfortunately, some woodpeckers try to place such a cavity in the side of a house, barn, utility pole, fence post, or other man-made structure.
Like most birds, woodpeckers breed in the spring, but they roost in holes (one bird per cavity) each and every night of the year. When aggressive woodpeckers are a problem, all one has to do is provide a man-made nest box directly at the site that is being damaged. People often put up bluebird boxes or purple martin houses to attract those species; this is basically the same thing, but more to accommodate the woodpecker. As you continue to read this pamphlet, you will see plans for building such boxes, and you will read a true story behind the model home that experienced extensive woodpecker damage in the past.
Over the years, there have been many solutions proposed for this problem. Most have come from "product-driven" companies trying to make a sale without identifying the actual cause of the problem. There are many expensive products: from pepper sprays to special paint additives that supposedly deter woodpeckers. These products usually do not work since woodpeckers are actively chiseling away wood and they do not ingest or taste what they are excavating. Woodpeckers even chisel away at creosote-soaked utility poles with no harmful effects to the bird.
An exception to the woodpecker damage mentioned above are the feeding wells created by Yellow-bellied Sapsuckers, a wintering bird in most urban sites in Texas. These sapsuckers make holes in the bark of any sap-flowing trees (usually young trees). The birds later visit these wells to eat the sap along with any insects caught in this sticky substance.
This publication includes plans to construct your own nest/roost boxes. These plans were made available with permission from the Minnesota Department of Natural Resources. Should you choose not to construct your own box, there are several places that sell them. Simply run a search on the internet, or visit your local bird supply store. Good luck in satisfying both you and the woodpecker; it can be done and it certainly makes a great conversational piece!