Help! We have birds trying to build a nest on a second story window ledge. We’ve been trying to chase them off with a garden hose, but two hours later they’ve repaired the nest and added more. I’m not sure what kind of birds they are, but this isn’t the first time that birds have tried to nest on these ledges. Any advice? B.T., Revere, MA

Sparrow with nestlings

My first bit of advice is to have a pest control company that does bird work identify the birds. The reason is that most birds are protected by federal law and you cannot harass them or destroy their nests. There are three species of pest birds (house sparrows, starlings, and pigeons) that are not generally protected, although this differs from state to state.

Pest Birds or Protected Birds?

If your birds are house sparrows, for example, then you, or a professional, are usually free to destroy the nest or discourage the birds. Since pest birds like sparrows are so persistent and so prolific, you may have to repeat the measures every 10-14 days during the breeding season to keep birds from returning for their next brood. A Colonial bird specialist can remove the nest of a pest species and treat the area to kill any parasites from the nest.

If your birds are a protected, migrating species, there isn’t much you can legally do once nest building is underway. You can’t even touch a protected bird’s nest without a special permit (see Can You Legally Remove That Bird’s Nest?) The federal law (Migratory Bird Treaty Act) in question was enacted in 1918 to protect nesting, migrating birds. Today, even though many of these birds are year-round residents in your yard, they are still protected by Uncle Sam. Once the young in a protected bird’s nest have fledged and left the nest, you are free to destroy and remove the nest.

Bird-proofing Measures Can Stop Nest Building

Your bird specialist can also recommend changes that will make those window ledges less desirable to birds as a nest site in the future. At Colonial Pest, we specialize in bird-proofing of buildings. There are various repellents, including prongs and wires that can be used to block birds from the ledges. Sometimes, simply adding a slant to the surface of the ledge will make it unsuitable for nesting. Netting can also be put in place temporarily over the ledges and removed after nesting season. Give us a call today!

Photo credit: d a murphy / Foter / CC BY