As the seasons change, our thoughts generally turn to ideas of refreshing our spaces. There is something about each new season that sparks a desire for updating our surroundings, whether it is switching out our decor, decluttering from the previous season, or preparing our homes for changes in weather or an increase in visitors. So, what about backyard wildlife? There are several things to consider when maintaining your birdhouse or nest box. We will try to cover as much as possible from whether or not you should clean out the nest box to when and how to clean them.
The first thing to consider is that not all nest boxes or birdhouses are treated the same way. According to The Cornell Lab of Ornithology’s NestWatch program, cleaning an Eastern Bluebird’s home between seasons might be more beneficial in some areas over others, and there is no need to clean a House Wren’s nest…. At least not every season.
House Wrens are generally good housekeepers and will clean their nests between broods and between seasons. This means that the likelihood of buildup and the parasites that feed on that causing problems for the next season are reasonably low. My recommendation would be to check on your House Wren nest box between seasons for any maintenance issues and clean accordingly.
Eastern Bluebirds, on the other hand, leave their mess behind when they are done nesting for the season. NestWatch members have studied Eastern Bluebird houses, and the numbers have come back somewhat confusing. It has been established that the birds prefer ready-made structures, so they readily take to a nest box. However, one study showed that they preferred a clean house each new season, and then just 10 years later, the majority of the birds studied preferred houses with the nests still in them and simply built on top. The issue with that is that Eastern Bluebirds will build a new nest on top of an old one again and again with no regard for the danger of running out of space. In this case, I would highly recommend cleaning the nest box at least every other season and check for any maintenance issues between seasons.
In all cases, I also recommend cleaning the outside of the box thoroughly after each season. Droppings and debris are not just unsightly, they can cause health concerns in people and animals.
When to Clean:
All things considered, you definitely want to clean your birdhouse or nest box before it gets out of hand, even for those helpful guests who clean up after themselves. Birdhouses and nest boxes are designed to emulate natural shelters for the birds, while looking attractive in your yard or garden, but that does not mean that you can’t help Mother Nature (and the birds) out every so often.
Always make sure that the nest is empty and that all the birds have left for the season. The Cornell Lab of Ornithology is an excellent resource to determine nesting season. Other signs will be a dilapidated-looking nest free from any birds or eggs. Usually fall is a prime time to clear out old nests so that it will be ready for birds to scout in the late winter or early spring.
It is not necessary to remove nests from natural sites, such as tree branches or bushes. In fact, it may be better to leave the nest. However, if the nest is in an unsafe place such as a drainage pipe, chimney, or dryer vent, among others, moving the nest is best. If the nest appears to be active (eggs or birds are present, for example), please contact a local bird rescue.
Rodent pests are another concern. If you notice mice or other pests attempting to nest in your bluebird or wren houses, cleaning the house thoroughly and plugging the entrance hole over the winter is best. If you notice them eyeing an owl nest box, feel free to leave them be (as long as they won’t pose a problem to your property). They will be a welcome treat to owls scouting a nesting site.
How to Clean:
Use a natural cleaner, such as the JCs Wildlife Birdhouse Cleaner or 3B cleaner (which also cleans bird feeders and even bird seed). Our cleaners use all natural enzymes and are safe for birds, humans, pets, and other animals.
For a good, deep cleaning, I recommend using the Birdhouse Cleaner. It can be used with or without water. For best results, clean the nest box or birdhouse at the end of the season using the enzyme cleaner, and then mist the house down in late winter or early spring before the birds return.
For your own protection, wear gloves and a mask when handling the nest. Old nests can be disposed of in the trash or even added to your compost.
For bigger jobs, such as a Barn Owl nesting box, a trowel to scoop out pellets and nesting material would be beneficial.
Use a scrub brush to work in the cleaner inside the nest box. Pay particular attention to any nooks and crannies, corners, and kerfs. Switch to an old, clean rag to wipe down inside and out once the scrubbing is done.