Promoting natural habitat is the best way to provide nesting opportunities for birds. Dead trees are an excellent source for nesting cavities. These snags also offer insects shelter where they complete their life cycle; many species are integral to decomposition and serve as a food source for birds and other wildlife. If you don’t have many dead trees around your yard, you may consider mounting nest boxes. Late February and early March is a great time to do so.
Nest box considerations:
- Nest boxes are not one size fits all and should be specifically tailored to the bird species you are trying to support. For instance, the size of the entry hole and the height that boxes should be mounted varies depending on the birds you are trying to attract.
- Some birds prefer boxes with additional nesting materials. Eastern screech owls do not build their own nests so it is good practice to place 2-3 inches of wood shavings in the bottom of your box. Do not use cedar or sawdust as nesting material.
Features of a good nest box:
- A sloped roof channels rain away and reduces access to predators.
- Recessed floors make nests less accessible to predators and helps to keep nests dry.
- Drainage holes
- Ventilation holes
- A hinged door creates an access point to easily clean and monitor the nest box.
- No perches
- Interior grooves serve as a ladder for birds to climb out of boxes.
- Mount boxes on metal poles, or incorporate predator guards to protect nestlings from climbing predators. Common predators include cats, squirrels, rats, chipmunks, raccoons, and snakes.
Monitor your boxes for invasive bird species
European starlings and house sparrows outcompete native cavity-nesting birds. They are known to steal occupied nests and even kill nestlings and adults of other bird species. The images on the left show European starlings and the righthand images are of a male and female house sparrow, respectively.
Here are some options if you are in an area that is known to have these species.
- Opt for nest boxes with smaller holes. Starlings cannot fit through a hole less than 1 ½ inches and house sparrows require holes that are 1 ¼ inches or larger.
- Monitor your nest boxes in early spring. If you notice a house sparrow or European starling building a nest in your box, continue to pull out their nesting material and they should eventually give up.
- Avoid feeding these species. House sparrows prefer smaller seeds, like millet and cracked corn. Starlings like eating black-oil sunflower seeds. Use feeders that have smaller ports and shorter perches and do not scatter seed on the ground.
- Here is a useful link from Cornell’s Lab of Ornithology on managing for house sparrows and European starlings – https://nestwatch.org/learn/all-about-birdhouses/managing-house-sparrows-and-european-starlings/
Most importantly enjoy observing and supporting the birds that are attracted to your backyard!
For more information on nest boxes visit: https://nestwatch.org/
Natural Neighbors is working with a local contractor to build and mount nest boxes. If you are interested in these services feel free to email firstname.lastname@example.org for more details.