Nesting boxes and roosting boxes are both structures that provide shelter for birds, but they serve different purposes. Nesting boxes are designed to provide a safe place for birds to build nests and raise young, while roosting boxes give birds somewhere to sleep at night.
What is a nesting box?
A nesting box, also called a birdhouse or bird box, is a manmade structure placed outdoors to mimic natural cavities that provide birds with a place to nest and breed. Nesting boxes typically have an entrance hole on the front and are made of untreated wood, although other materials like metal or concrete may be used. The interior often contains a wooden base or nesting tray to give the nest structural support.
Nest boxes come in different sizes and styles to attract certain species. Small boxes with 1-1 1⁄2 inch entry holes are preferred by chickadees, nuthatches and titmice. Bluebirds like nest boxes with 1 1⁄2 inch holes placed 5-6 feet off the ground with no perch. Larger boxes with 3-4 inch holes are used by owls, woodpeckers, ducks, kestrels and other birds.
Nesting boxes should be placed in suitable habitat for the target species and securely mounted on trees, posts or buildings. They should face away from prevailing winds and intense sunlight. Nest boxes are intended to keep eggs and baby birds safe and warm while also protecting them from predators.
Benefits of nesting boxes
- Provide vital breeding sites for native birds
- Allow people to observe bird nesting behaviors up close
- Control invasive bird species like house sparrows and European starlings when using properly sized entry holes
- Give birds shelter in areas with diminishing natural nesting cavities
What is a roosting box?
A roosting box provides shelter for birds to sleep in and escape from predators overnight. They are similar to nesting boxes but do not contain nesting materials and are solely used for roosting purposes.
Roost boxes typically have a larger interior and include perches for the birds to grip while sleeping. They also often have ventilation holes and drainage gaps since they are not meant to maintain heat like a nesting box. Roost boxes can utilize the same materials and mounting methods as nest boxes.
Roost boxes may be placed closer together than nesting boxes to create communal roosting spaces. Certain species prefer to roost in groups for safety reasons. Roosts are typically installed at least 10 feet high on trees, buildings or poles.
Benefits of roosting boxes
- Give shelter to migrating flocks needing rest
- Provide winter refuge for birds that do not migrate
- Allow safe spots for sleeping away from nocturnal predators
- Help supplement declining natural cavities for roosting
Differences between nesting boxes and roosting boxes
While nesting boxes and roosting boxes both provide enclosed spaces for birds, there are several key differences.
Nesting Box | Roosting Box |
---|---|
Intended for nesting and breeding | Intended for sleeping/perching |
Contains nesting materials like twigs | Does not contain nesting materials |
Has drainage holes but optimized for warmth | Has ventilation and drainage holes |
Usually has a small entrance hole | Typically has a larger entrance hole |
Only used by one breeding pair | Can house multiple roosting birds |
Installed apart from other nest boxes | Can be clustered together |
Placed lower to the ground | Usually installed high up |
The different purposes of nesting and roosting boxes means their placement, specifications, and intended use by birds is unique. Understanding these variations allows birders to install the most suitable boxes to effectively support local bird populations.
Selecting nesting box designs
Many factors go into choosing an appropriate nest box design for your property:
Box size
The interior floor dimensions dictate what species can fit inside. Floor areas ranging from 4×4 inches up to 10×18 inches are common.
Entrance hole size
The entry hole diameter ranges from 1 inch to 6 inches across. A 1-1 1⁄2 inch hole is used by small songbirds, while larger holes accommodate ducks, owls and woodpeckers.
Height off the ground
Most nest boxes are installed 5-15 feet high on trees or posts. The height depends on the target species and their vulnerability to predators.
Materials
Unfinished wood is ideal, since it’s breathable and provides grip for hatchlings. Avoid treated lumber, plastics or metals which can overheat.
Design elements
A sloped roof sheds rain while a partially open front panel allows cleaning. Ventilation holes provide airflow. Some boxes have predator guards to block raccoons.
Placement
Locate nest boxes where birds naturally congregate. Face the entrance away from prevailing winds and intense sun. Avoid aiming the hole towards trees or fences where predators roost.
Selecting roosting box designs
Factors to consider when installing roost boxes include:
Interior space
Roosts should have ample room for multiple birds to perch together. Longer boxes provide more headroom.
Perch type
Natural wood perches give birds a good grip while sleeping. Some roosts have interior perches while others just have a textured floor.
Ventilation
Breathability is important so avoid plastic or solid wood roosts. The front can be left partially open for increased airflow.
Drainage
Holes along the bottom allow rainwater to drain out instead of pooling inside.
Mounting location
Mount at least 10 feet high overlooking preferred roosting areas. Having cover nearby offers further protection.
Visibility
Roosts should be visible to birds but obscured from predators. Mounting between tree branches can provide camouflage.
Protection from elements
Roosts mounted on north or east sides of trees stay drier. Angling the roof down shields the entry from wind-driven rain.
Conclusion
Nesting boxes and roosting boxes both help support bird populations by mimicking the natural cavities they rely on for shelter. Understanding the different purposes of each allows you to select designs tailored to the target bird species and their needs.
Nesting boxes should provide an enclosed secure space for breeding birds to safely lay eggs and raise young. Roosting boxes give sleeping birds a place to congregate away from nighttime predators. With the right placement and specifications, both nesting and roosting boxes can attract local species searching for a home.