Clean birdhouses in the fall to increase spring nesting


Archuleta County enjoys many species of migrating birds each spring, and many of us construct birdhouses to encourage their nesting. To help prevent disease and predators, cleaning birdhouses is recommended in the fall.

The following article was written by Pat Brodbent and was published in the fall 2013 edition of the Sustainable Small Acreage Newsletter published by Colorado State University Extension, the USDA and the Natural Resource Conservation Service. For other articles published in the newsletter, visit

Birdhouses are an excellent landscape feature, increasing the number of songbirds on your property.

Attracting songbirds to your backyard is easy and can be very beneficial in keeping many daytime pests (grasshoppers and mosquitoes) and rodents under control. Each fall or early winter, your birdhouses should be cleaned out and repaired. Doing this in the fall rather than spring will increase the chances of your birdhouse getting used again the following spring.

To clean out a birdhouse, just open it up, take the old nest out, scrape any feces off the sides, clean all the vent holes, and check and remove any wasp nests from the ceiling.

All birdhouses should have a way to be opened easily for cleaning. If your birdhouses are not easy to open, I would suggest replacing them.

Also, all birdhouses should have vents on the bottom, both sides and the back. You also want to replace any worn or broken parts. If the birdhouse is in really bad shape, replace it with a new one.

When cleaning out your birdhouse, ensure that the roof, sides, front and bottom are in good shape. If any of these parts are cracked or broken, they should be repaired or replaced.

Cleaning out your birdhouses in the fall allows the many cycles of freezing to naturally kill eggs from critters that may be attached to the wood surfaces. Getting rid of the old nesting material allows the cavity to thoroughly dry during the winter months. This drying process is also very effective in killing off any bad bacteria that can affect nesting birds in the spring.

Top 10 reasons to clean and repair birdhouses

10. Cleaning out, repairing or installing a new birdhouse in the fall will significantly increase your odds of that house being used in the spring by a cavity-nesting bird.

9. Hundreds of little insects can live in old nests. Critters such as spiders and mites will multiply by the hundreds if allowed to stay in a birdhouse until spring.

8. Old, packed nesting materials and feces will hold moisture, allowing bacteria to grow and thrive all winter. The bacteria in these nests can cause disease and death in the springtime nesting birds. The baby birds are especially sensitive.

7. Repairing the entry hole of your birdhouse is critical. Entry holes can become enlarged from woodpeckers over the year. The enlarged holes enable predators, — such as magpies, grackles, starlings, squirrels and feral cats — to easily kill the nesting birds in the spring. A predator guard is also highly recommended.

6. Leveling the birdhouse to make sure the house is not tipped back will ensure next year’s fledglings will have an easier time getting out of the entry hole. Even a house tipped back 1 degree can cause a high percentage of fledgling deaths.

5. Most all cavity-nesting birds eat insects. One of the most common cavity-nesting birds in Colorado is the tree swallow. A single tree swallow will consume more than 500 mosquitoes or as many as 50 miller moths per day. One family: dad, mom, three to five babies, up to one family per 5 acres … that’s a lot of insect consumption.

4. Another cavity-nesting bird in Colorado is the western or mountain bluebird. Both are huge consumers of moths and grasshoppers. Up to 40 grasshoppers and 40 moths can be consumed per day by a single bluebird.

3. Birds like to use birdhouses for roosting in the winter time. The chances of birds using a nesting box for roosting during the winter significantly increases with a clean birdhouse.

2. Cleaning out the old nests can be very educational for both children and adults. See how birds make their nests, what materials were used and what kinds of feathers you find. These clues will give you tips as to what type of bird used your box last season. If you find the box was filled with sticks, you can be assured wrens are in your area.

1. An unused nesting box can attract wasps. Many times one or more wasp nests will form on the inside roof of the box. Removing these wasp nests is the only way you have a chance of birds using the box next spring. Leaving the wasp nests ensures you will have many, many more wasps in your yard next year.

Free wood chips

We are cleaning up the fairgrounds and all of the wood chips that helped keep things dry during the fair are available to anyone for pickup. If you are interested, just bring your pickup truck and haul it away. No need to call the Extension office for permission.

CPR and first aid

CPR and first aid certification classes are offered monthly by the CSU Extension office on the second Monday and Wednesday of each month from 6-10 p.m. Anyone needing to receive or renew certification can register by calling the Extension office at 264-5931.

We will also schedule classes on additional dates with five or more registrations. Cost for the classes is $80 for combined CPR/first aid and $55 for individual CPR or first aid. Group rates are available.

The type of first aid information provided will vary by the needs of the audience. Call the Extension office at 264-5931 for information.