Bird Nest Boxes Guide
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Giving local birdlife a safe space to nest is among one of the most important things you can do for wildlife. But just as humans have specific needs when it comes to somewhere to stay, so do birds, and ensuring you set up your nest box in the right way will also ensure success.
What are the Benefits of Putting up a Bird Nest Box?
There are plenty of advantages to putting up a birds nest box, but most importantly, you are giving local birdlife a safe space to take shelter away from predators. Moreover, it allows lots of species to nest and raise their young without as many dangers. This is especially important owing to the decline of natural habitats.
Provides a Place for Birds to Nest & Shelter
Installing a bird box in your garden is a great way to attract cavity-nesting birds. These birds lay and take care of their eggs in an enclosed cavity, so a nest box is essential to them. You may be surprised at just how many of these species there are. While we could not include an exhaustive list, here are some of the most common cavity nesters:
- Several species of chickadee including black capped and Carolina
- Tufted titmouse
- Zebra finch
- Lucy’s warbler
- Brown creeper
- Purple martin
- Tree swallow
- American robin
- Several types of bluebird including Western, Eastern and mountain bluebirds
- House wren
- Tawny owl
The problem is that, due to human developments, there are fewer and fewer natural nesting spaces for these birds. In urban areas there are not as many trees, shrubs, and other environments for cavity nesters to raise their young safely. Therefore using nest boxes is something we can all do to help our feathered friends.
You’re Helping to Stop the Decline of Bird Populations
In recent decades there has been a staggering decline in the number of birds in the USA and Canada. What’s most worrying is that some of the previously most common species are being the worst affected. According to one study, as much as 90% of the declining population is as a result of the loss of the 12 most common North American birds. These are the birds you’ll see in your backyard on a daily basis.
Other studies have shown that in the past 50 years, as many as 1 in 4 birds has been lost; that means that compared to half a century ago, there are a quarter fewer birds today.
This is worrying because birds are an important part of our ecosystem. While it may seem like an insignificant act in the scheme of things, putting up a nest box means you are doing your part to provide these birds with a safe space, which should go towards halting this decline. If each North American household installed just one bird box, imagine the difference it could make.
Encourages Birds to Use Your Garden
There’s nothing quite like getting back in touch with nature, but it isn’t always possible, particularly when you live in an urban area. But putting up a bird box is an excellent way to invite nature and wildlife right to your back door.
Your nesting box will allow you a front-row seat to a variety of different avian species giving you a chance to observe their daily activities. What’s more, if you have children, this is an excellent opportunity to help them learn and gain a first-hand education about local wildlife.
Additionally, birds are an important part of maintaining your yard. If you are a keen gardener, you will know how annoying pest problems can be for plants. But birds will eat many of these bugs, keeping your garden healthier.
With a nest box and other features such as bird feeders and a water source, you will find more and more birds are attracted to using your garden.
What Makes a Good Bird Nest Box?
There are a few factors to consider when it comes to making or buying a bird box. These are important as they will provide the safest and most effective space for the birds so before you install anything, give some thought to the following points.
Should be the Right Size for the Birds You Want to Attract
When buying or making a bird box, you will need to think about the type of birds you are trying to attract. This will largely depend on where you live as, of course, different species are common in different areas. It’s worth doing a bit of research to find out which birds live locally, and NestBox is a great place to start.
This handy resource allows you to discover information on which species require which things out of a nest box. Most importantly, you’ll be able to make sure that the dimensions of your nest box are suitable for the species you wish to attract.
On the website’s homepage, you will find a selection of birds, and you simply select the one you are focused on. You’ll then be given a plethora of information about that species, including the following:
- Natural nesting habitat
- Nesting range
- Where the nest box should be installed
- Nesting period
- Minimum hole size for the nest box
These things will help you to ensure that you install the most suitable nest box for your chosen species.
It’s also possible to buy a readymade bird box. This is not a problem, but again, you will need to make sure that the bird box is the right size for the species you are trying to attract. The opening hole should be the correct size, and the internal dimensions of the box should be enough to comfortably house a nesting pair and their young.
When buying a bird box, be sure you choose products that have been endorsed by things like the American Bird Conservancy. This gives you the reassurance that the product will be appropriate for its purpose.
Should Have Sufficient Ventilation
It is incredibly important to make sure that your nesting box has good ventilation. This airflow will ensure that the nest box does not become too hot inside particularly when the weather is warmer in spring and summer.
According to NestBox, you should have a total of four air holes located at the top of the box, one on each wall. The best size for these holes is ⅝ inch.
Must Have Adequate Insulation
As well as ensuring adequate airflow, it is also essential to make sure that your bird box is properly insulated. While there are bird boxes made from materials such as plastic and ceramic, these don’t typically offer sufficient insulation.
Wood is the best material to choose, and to narrow it down even further, we would suggest hardwoods like cedar or oak. For proper insulation, you will need to make sure that the walls of the box are at least ¾ inch in thickness. Not only will this work well for insulation purposes, but thick, hard wooden structures will also be much more difficult for predators to get through.
A Slopping Roof & Drainage Holes Prevents it from Getting Flooded
Birds will not do well in a wet nest box. In the worst cases, without proper construction, the box could flood, and this could kill the birds.
For this reason, it is essential to make sure that your roof has a slope that allows rainwater to flow off. This sloped roof should extend past the opening so that any falling water has no way of flowing into the nest box opening. You’ll want at least ¼ inch overhang.
Another reason that a sloped, overhanging roof is important is that it will deter predators. It will be much more of a challenge for them to sit on top of the bird box, and the overhang prevents them from being able to access any chicks that emerge.
As well as a sloped roof, you should include drainage holes in the base of the nest box. This will allow any moisture to drain away. NestBox suggests using one ½ inch drainage hole at each of the four corners of the base.
Must Be Easy to Open & Clean
Keeping your nest box clean is essential. Just like us, birds need a hygienic and sanitary space in which to nest and raise their young. This is why it is so important to be able to gain easy access to the nest box to perform maintenance and cleaning.
The bird box should easily open up, allowing you access to all parts to ensure full and proper cleaning. This feature will also allow you to get rid of any other animals that may have taken shelter inside, such as mice.
Wood Should Be Untreated
While we are always told to treat wood for outdoor use, this does not apply to bird boxes. Treatments may be unsafe for the birds, so should always be left off. If you do wish to paint your bird box, it is safe to do so on the outside, but the interior should be left untreated or painted.
There are some types of wood you can buy that are untreated but suitable for outdoor use as they’re much more hard wearing. Look for wood labelled as ‘non-pressure treated CDX exterior grade.’
Have a Predator Guard to Prevent Unwanted Visitors
Birds have many predators, and if these animals are allowed easy access to the nest box, they will almost certainly kill the young birds or eat any unhatched eggs. The most common predators include things like raccoons, squirrels, woodpeckers, and even domestic cats.
Fitting a predator guard such as a collar, noel guard, or stovepipe will keep predators out of the box. Furthermore, it will prevent them from being able to gnaw at the opening, making it larger and allowing them access. Some bird boxes come with a metal ring that fits around the opening hole and will be far too hard for predators to get through.
Avoid Perches
Many people are under the impression that a bird box should have a perch. While birds indeed do like to perch, this is not necessary in a nest box as it can make it easier for predators to gain access.
Predators could use this perch as a foothold while they reach into the box to take eggs or hatchlings. Other features such as a protruding base could serve the same purpose, so it is best to avoid these as well.
Where to Site a Nest Box?
Choosing the right location for your bird box is just as important as how it is designed. One of the main points to keep in mind is that the box should not be placed in direct sunlight. A shady spot is best. But there are lots of other factors to consider, such as placement height and how many bird boxes are in the near vicinity.
Place at the Right Hanging Height
Usually you would place a nest box on a purpose built pole, or they can be attached to a tree. In any case, the right hanging height is a key factor. The type of nest box you are using will determine the best height. For example, an open front bird box should be placed between one and two meters from the ground, while a box with a small hole should be higher at between two and four meters.
Different birds will nest at different heights, so it is also worth researching this in line with the species you are trying to attract. Moreover, you will want to make sure that predators cannot access the box and choosing the right height can help with this. For example, many predatory animals find it challenging to climb a pole so this may be a better option. However, if you do choose a pole, it is essential to also install a baffle to make it more difficult for things like snakes, chipmunks, and squirrels from gaining access.
When you have chosen your location, you should ensure the nest box is securely fastened. Using either stainless steel or galvanized screws will prevent rust from forming and create a stronger attachment.
Place Away from Direct Sunlight
If you position your nest box somewhere with direct sunlight, this can cause the inside to overheat more easily, especially in the height of summer. In the main, you will find that this puts the birds off and they won’t come to nest.
It is best to position the box so that the entrance hole is facing north or east. If you have a shady spot in your garden, this is usually the best option. Placing the box so that it is facing west where it will be exposed to prevailing winds or south where it will have a lot of direct sunlight could be dangerous for the birds, especially the young. Of course, it is again worth doing your research as the needs of different species will vary somewhat.
But you should also consider how easy it is for the birds to gain access to the box. You will need to ensure a clear flight path to the entrance.
Don’t Position too Close to Other Nest Boxes
Birds are territorial animals so placing several nest boxes in close proximity to one another is only going to lead to problems. It is perfectly acceptable to have more than one bird box in your garden but try to place them evenly apart. Moreover, it is essential to make sure that there is enough food and water nearby to serve each nest box.
That said, there are some species, such as the tree swallow, that prefer to nest in pairs, so placing two bird boxes on one pole in opposite directions could encourage this. Otherwise, you should look to leave at least 15 to 20 feet between boxes.
Place Several in Different Locations
By placing several boxes in different locations, you will be able to help as many species as possible. Don’t forget that different species have different needs, and choosing a variety of locations will help to meet these.
Surprisingly, birds won’t always settle for the first nesting box they stumble upon. Many species will actually look around at different options and select one that meets their needs. The more boxes you have, the greater chance that birds will choose it.
Don’t Place them too Close to Bird Feeders
When birds are nesting and raising their young, they need a degree of tranquillity. This cannot be achieved if there is a lot of activity going on directly outside the box. This means avoiding placing your nest boxes too close to bird feeders or sources of water. The heightened activity could serve as a disturbance.
What Nest Material Should You Use in a Nest Box?
One of the most common questions when it comes to nest boxes is whether you should add any nesting materials. Birds will instinctively gather everything they need, but there is nothing wrong with giving them a helping hand. That said, there are certain materials you should avoid and others that are considered to be best.
You should always avoid using unnatural materials such as dryer lint, tinsel, plastic, and cellophane. If you are going to give the birds a helping hand, you should consider the following:
- Moss
- Twigs
- Dead leaves – these should be mixed with heavier items such as twigs and sticks
- Straw
- Some birds, like the bluebird, like pine needles as part of their nest so you can include these if this is the species you are looking to attract
- Plant fluff
- It is possible to use grass clippings but you should only do this if the lawn has not been treated with any chemical pesticides or fertilizers.
When Should I Put a Nest Box Up?
Different species of birds will nest at different times, so you should factor this into when you put up your bird box. However, as a general rule, you will want to do this before spring; February and March are typically the best months. But this does depend on where you are located. In the northern parts of the US, you will be able to install the box a little later, up until March. However, in southern states, where it is warmer, you should have the box in place no later than February.
With that in mind, there is no harm in putting up a bird box at any time of the year. Some species are known to start their mating rituals as early in the year as January, so it can’t help to be prepared. Moreover, it doesn’t matter what time of year you put the nest box up as birds will come and take a look.
Also, some species raise more than one brood each year, so if you put the box up at the end of spring, for example, you may still attract a mating pair.
How to Clean a Nesting Box
You cannot simply put up a bird box and forget about it; it’s imperative that you maintain it and keep it clean. This is important for several reasons. Primarily, you will want to prepare the box for the next pair. While some bird species such as the house wren will clean their own nests, others, like the bluebird do not. In fact, it is not legal to remove nesting material from the nest of a house wren until the pair officially leaves.
There is a risk to the birds where ectoparasites are concerned, although many wild birds have adapted to be able to cope better with these.
You may also wish to clean your nest box owing to the presence of other species. For example, bees and paper wasps are known to take over bird boxes and this can be problematic. However, should you find that this is the case, it is normally better to contact a professional exterminator to safely remove the pests. To avoid future problems, it is advised to coat the inside of your bird box with bar soap or cooking oil spray.
Other animals, such as mammals like mice and squirrels may use the nest box. Many people do not mind this since they nest at different times of year to the birds, so they don’t cause much interference. Furthermore, there are laws against disturbing the nests of certain animals like the squirrel, so even if you wanted to, you wouldn’t be able to clean the bird box until the squirrel has finished using it.
When mice and other mammals have used the nest box, we would recommend giving it a full clean before allowing birds back in. To do this, remove all nesting materials and wash the box with soapy water, rinsing it well. You should always wear gloves when cleaning to avoid contamination.
Choosing whether to clean your bird box is a personal matter. If you do decide to clean it, then it is best to do this in fall or winter in preparation for the next pair that will use it in spring. Again, keep in mind that this doesn’t apply to certain species, such as the house wren.
When cleaning, never use any chemicals that could be harmful to the birds, such as insecticides or flea powders. In some cases, simply pouring boiling water through the box can be enough to kill germs and sanitize everything.
Can I Look Inside My Nest Box?
One of the reasons that a lot of people install a nest box is to be able to observe birds. Sitting back and watching from afar is the best way to do this and will cause the least disruption to the birds. However, you may wish to check inside from time to time to monitor the activity. This allows you to monitor local wildlife as well as ensure that the chicks are healthy.
You should check your box infrequently and when you do this, keep in mind the nature of the birds that are nesting. Some species will be much more receptive to human contact, while others will be very frightened and this can cause them stress. Checking twice a week is more than enough, and don’t keep the box open for longer than necessary.
Before opening the box, give the birds a warning that you are there so as not to startle them. You can do this by lightly tapping on the side of the box.
Also make sure that you only open your nest box when the weather conditions are favorable. Choosing to open the box when it is raining or cold could disrupt the conditions inside and cause the chicks to become cold.