Backyard: Woodpeckers can damage homes

What do you do when a woodpecker adopts your home? Because all native bird species are protected by federal laws, woodpeckers cannot be trapped and removed in the same way that one can dispatch a troublesome mouse or squirrel. The best and only legal strategy is to thwart the behavior by first understanding what is motivating the bird.

In theory, you can apply for a federal permit to kill the birds, but this is likely to take a long time and your request denied, given how busy federal animal control agents are with annually killing 1.75 million coyotes, wolves, geese, blackbirds and other animals that threaten agricultural and commercial interests.

Woodpeckers damage homes for three reasons:

• They may be extracting insects to eat, especially the huge larvae of carpenter bees. This leaves multiple small holes, usually in wooden trim.
• They may be excavating a nest or roosting cavity. This produces fist-sized holes.
• They may be — this goes for most nuisance woodpeckers — using the home as an amplifier to advertise their mating signal. Because woodpeckers evolved before songbirds, they cannot sing and instead attract mates and deter rivals by drumming out their messages on resonant surfaces.

The solution to domestic woodpecker problems depends on why they are using your home. For example, placing nest boxes on the home or a nearby tree will often prevent woodpeckers from excavating a nest in your siding. But this solution will not improve the problem if woodpeckers are systematically hunting down insects that have invaded your trim.

The first step in solving the problem is to accurately observe it. How many woodpeckers are there? What kind of woodpeckers are they? What shape and size are the holes? Are they drilling into something that might contain food? Are they simply making a racket on your gutters? The last problem is the most commonly reported and can be quite irritating when it wakes you up at dawn, but it does not usually harm the home.

Once you have determined whether the woodpeckers are eating, nesting or displaying their maleness, you can design a deterrent and repair the damage. Most marketed deterrent systems have not been scientifically tested, or if they have, they are not more effective than the solution of doing nothing. These include model owls, loud noises, chemical sprays and hawk decals.

One solution that often works is the installation of Mylar or foil strips that wave in the breeze and flash reflected light. Hanging these near the sites of early nest excavation or drumming displays will likely keep the woodpeckers away because the deterrent is unpredictable, and woodpeckers will not easily learn that it is harmless. However, the birds may quickly move to another location nearby and continue.

Covering holes with metal flashing will stop drilling at that location, whether for food or a nest, more effectively than wood putties. A cheap solution is to use discarded can lids and then repaint. In a study from New York, one of the main factors in determining which houses receive woodpecker damage was the color of the siding. Stained and natural-colored wood was more likely to be attacked than painted surfaces, especially light blue, white or pastel colors, which were generally left alone.

To summarize: If woodpeckers are starting to nest in your home, provide them with several nest boxes, and they should accept them as a preferred substitute that requires less work. If they have already completed a nest, wait until they are done in midsummer, cover the hole with metal, repaint it and hang some flashy strips nearby.

If woodpeckers are extracting insects from your home, they are doing you a favor. Replace the insect-infested wood with a treated or synthetic product and see the value of your home increase.

If woodpeckers are banging on or ripping up parts of your home to impress other woodpeckers, the problem is more difficult but should also be limited to a month or two in the spring when testosterone is flowing. Erecting flashy strips at the points of display and moving them around as the woodpeckers adjust their activity is your best solution, but it doesn’t always work.

Observe, try to think like a woodpecker and please, don’t fall off a ladder.

Dan Cristol teaches in the biology department at the College of William & Mary and can be contacted at dacris@wm.edu. To discover local birding opportunities visit http://williamsburgbirdclub.org.