Many backyard birders enjoy putting up birdhouses, providing safe havens for their favorite backyard birds and their young. Most people leave their birdhouses up all year round, but do birds actually stay in their houses all year long? Do birds use birdhouses in the winter?
You may be surprised to find out that birds do make use of birdhouses in the winter. Not all birds migrate to warmer climates during the colder winter months, and not all birds nest in trees or shrubs. Birdhouses provide birds a place to roost and get out of the cold during the winter for those that use them.
Not every type of bird uses a birdhouse. However, the birds that use them in the summer, are the same birds that will use them in the winter. Birds that use birdhouses, as compared to those that make their nests on a tree limb or shrub, are called “cavity nesters”. These birds look for holes in trees, or other natural enclosures, to make their nests. Since there are more birds than naturally made holes to nest in, birdhouses provide great additional cavities for nest building.
Why birds use birdhouses: nesting and roosting.
Nesting occurs in the spring and summer months, when birds build their nests and lay eggs. Birdhouses provide a place for egg-laying and young to safely hatch and grow. During this time of year birdhouses are sometimes called “nest boxes”.
Roosting is the term used for when birds are resting or sleeping. Birds certainly need a place to rest and get out of bad weather in the warmer months, but during the winter finding warm, dry places to roost is critical. Birdhouses can provide a great environment to escape from the cold, and are often called “roost boxes” during the winter months.
Where do birds sleep in the winter?
Every animal can benefit from protection from cold nights, ice & snow storms, and hungry predators. During the winter, birdhouses provide protection for the birds from both the weather and other animals. They also provide a place for multiple birds to rest and gain warmth from each others bodies.
During the winter birds can sleep in a variety of places, such as:
- Landscaping: This includes trees, shrubs, and ground cover. The more foliage the landscaping has during the winter (such as evergreens) the better protection for the bird.
- Brush pile: The piles of dead leaves that fell during the fall provide a place to nest during the winter.
- Roosting pockets: Roosting pockets are different from birdhouses in that they are made of straw (or similar material) and provide a small and insulated space for birds to spend the night.
- On the ground: Birds can sleep anywhere in the winter, including huddled together on the ground for warmth.
- In cavities: Holes in trees, the rafters of a barn, underneath decks, roost-boxes, etc. Any cavity that shields from the elements.
How do birds keep warm in the winter?
If a bird chooses not to sleep in a birdhouse during the winter, how do they keep warm? Birds keep warm through two main ways: body fat and feathers. Like other animals, some birds store body fat all year long to use both as an extra layer for warmth and a food source during winter.
Bird feathers also provide a source of warmth during the colder months. Their feathers, especially the inner “downey” feathers, are insulating. Which means that they trap heat against birds bodies, and provide relief from the cold.
Birds can also fluff their feathers to create more warmth. Birds fluff their feathers, which moves the heat from their body into the layers of air between their feathers. By puffing their feathers up they are creating the largest warm air pocket around themselves that they can. Birds can also hide exposed body parts, such as a beak or a leg, within their feathers.
When all else fails, multiple birds can gather in a group and use the group’s body heat to keep themselves warm. Group roosting can be done inside or outside of a birdhouse, and depends more on the number of birds, than the place where it is being done.
To learn more about the many tactics birds employ to make it through the coldest months, visit our article about how birds survive in the winter.
How can we help birds during the winter?
Besides providing a birdhouse, there are other ways that we can help birds keep warm during the winter:
- Offer food: With a decreased supply of insects, berries and plants, food is harder to come by in the winter. Searching for food and keeping warm depletes the bird’s built-up fat reserves, so providing birds with consistent food through the use of a bird feeder is a great way to help birds out during the winter.
- Provide water: Water sources freeze during the winter and a typical bird’s beak is not strong enough to break through the top layer of ice to reach the water underneath. Providing a water source for birds during the winter prevents them from dying of dehydration. Heated bird baths work great for this.
- Provide shelter: Aside from a roost-box, planting some evergreen shrubs or making brush piles will give birds a place to get out of the wind and weather.
How to prepare a birdhouse for the winter
In order for birds to use a birdhouse during the winter, there are some steps that must be taken to convert it into a proper environment for roosting.
First, the birdhouse needs to be cleaned. This includes cleaning out any old nesting materials inside the birdhouse and repairing any damage before winter comes.
The second step to preparing a birdhouse for winter use is to insulate the inside to provide lots of warmth. Any air holes or cracks in the birdhouse should be blocked so that the birds remain warm and dry. Ventilation that was necessary for air flow during warm months can be plugged up during the cold.
Next, you want to try and create perches. When birds roost they like to sit next to each other in tight rows and huddle together to use their collective body heat for warmth. They much prefer, and there will be room for more birds, if they can perch rather than sit on the bottom of the box. Try adding in a twig or a wooden dowel.
Lastly, you will want to make sure that the birdhouse is properly placed. To maximize heat, make sure it is in a spot that gets a lot of full sunlight, and if possible is protected from strong winds. Also be sure it is placed up and away from predators.
How are roost boxes different from nest boxes?
As we discussed above, you can use a birdhouse for both a nest box and a roost box with just a few tweaks. However you can also purchase roost boxes that are designed specifically to just be for winter use. You may notice these look a little different from nest boxes.
They are usually much taller. This is to allow multiple rows perches to be placed on the inside, so the maximum number of birds can use the box at once.
The entrance hole is usually located on the bottom of the box as opposed to near the top. This is because warm air rises. Any warmth created by the shelter and the birds body heat will be better retained if it cannot escape from the top of the box, and keeping the opening at the lowest point helps this warm air stay in.
Maintain predator protection on your birdhouse during the winter
In the winter multiple birds may be using the same birdhouse to take advantage of group roosting and each others body heat. If a predator gets into it a birdhouse during a winter night, it can potentially result in the loss of seven or eight birds rather than one or two.
This is why it is especially important that winter birdhouses should be placed away from the ground, and in a place where climbing predators will have a hard time reaching it. Predator guards around the entrance hole and baffles on poles used to keep predators away during nesting season are still important to use during the winter.
Enjoy winter birdwatching!
Just because the spring nesting season and warm summer months are over doesn’t mean your birdwatching is too. Winter is one of my favorite times of year to watch backyard birds. If you provide food and places to shelter such as roost boxes, you will have an abundance of birds to watch all winter long.
As lovers of birds we want to help them as much as we can, and the winter is when they need your help the most. So keep those feeders full, plug in a heated bird bath, create a few brush piles and a roost box, and enjoy!