Will Swallows Nest in a Bluebird House? Exploring Nesting Preferences and Coexistence
Will swallows nest in a bluebird house? The short answer is: yes, swallows, particularly Tree Swallows, are highly likely to compete with bluebirds for nesting sites and may even nest in bluebird houses themselves.
Understanding Bluebird and Swallow Nesting Habits
Bluebird houses are intentionally designed to provide safe and suitable nesting environments for bluebirds, offering protection from predators and the elements. However, the desirable features that attract bluebirds can also make them appealing to other cavity-nesting birds, including swallows. Understanding their distinct nesting behaviors is key to managing this potential competition.
The Appeal of Bluebird Houses to Swallows
Bluebird houses, by their very nature, offer several advantages for swallows:
- Protection from Predators: Enclosed spaces provide a safe haven for nesting birds and their young.
- Weather Resistance: A well-built birdhouse shields nests from rain, wind, and excessive sun.
- Pre-fabricated Cavity: Swallows, like bluebirds, are cavity nesters, and a ready-made cavity saves them the energy of excavating their own.
- Suitable Size and Entrance Hole: Bluebird house dimensions and entrance hole sizes often accommodate swallows comfortably.
Types of Swallows That Might Use Bluebird Houses
While several swallow species exist, the Tree Swallow is the most common competitor for bluebird houses. Other species, such as the Violet-green Swallow, may also occasionally utilize them, depending on the geographic location and availability of other nesting sites. Tree Swallows are particularly adaptable and readily accept artificial nesting cavities.
Managing Competition Between Bluebirds and Swallows
If you’re specifically trying to attract bluebirds, managing competition from swallows is crucial. Here are some strategies:
- Monitor the Birdhouse: Regularly check the birdhouse to observe which species is attempting to nest.
- Consider Multiple Birdhouses: Provide several birdhouses spaced far enough apart (at least 100 feet) to reduce direct competition. Bluebirds can be territorial and might claim multiple houses within their territory.
- Erect Swallow-Specific Housing: Place swallow-specific nest boxes nearby. These can be designed with features that might be slightly less appealing to bluebirds.
- Nest Box Traps: Some individuals advocate using nest box traps to capture and relocate swallows. However, this is controversial and should only be considered after consulting local wildlife experts and understanding the ethical implications. Always follow legal guidelines regarding bird relocation.
The Impact of Swallow Nesting on Bluebird Populations
Increased competition from swallows can negatively impact bluebird populations in several ways:
- Displacement: Bluebirds may be forced to abandon prime nesting sites.
- Delayed Nesting: Bluebirds may have to wait for swallows to finish nesting before they can claim a house.
- Reduced Brood Size: Stress from competition can impact bluebird breeding success.
Identifying Swallow Nests
Distinguishing between bluebird and swallow nests can help you understand which species is using your birdhouse.
| Feature | Bluebird Nest | Swallow Nest |
|---|---|---|
| —————- | —————————————————————————————– | —————————————————————————————— |
| Material | Primarily made of dry grasses, pine needles, and occasionally feathers. | Constructed of grasses, feathers (often many), and sometimes string or other debris. |
| Shape | Neat cup shape. | Can be messier and less defined, with a greater accumulation of feathers. |
| Location of Feathers | Feathers may be incorporated, but not as a prominent feature. | Swallow nests often have a noticeable abundance of feathers lining the nest cup. |
Benefits of Having Swallows Around
Despite the competition, swallows are beneficial birds:
- Insect Control: They are excellent aerial insectivores, consuming vast quantities of flies, mosquitoes, and other pests.
- Natural Pest Control: This natural pest control can benefit gardens and surrounding ecosystems.
- Enjoyable to Watch: Their aerial acrobatics are a delight to observe.
Frequently Asked Questions About Swallows and Bluebird Houses
Will other birds nest in my bluebird house besides bluebirds and swallows?
Yes, other birds may also attempt to nest in bluebird houses, including house wrens, house sparrows, and even chickadees. Careful monitoring and selective removal of unwanted nests (particularly house sparrows, which are invasive and aggressive) are important for bluebird conservation. Always check local laws and regulations before removing any nests.
Can I deter swallows from using my bluebird house without harming them?
Yes, you can deter swallows by trying to make the house less appealing to them. Consider using a Nesting Shelf or Gilbertson nest box, these design types are more attractive to bluebirds but less attractive to swallows. You can also try covering the entrance hole temporarily if you see swallows showing too much interest and bluebirds are present and ready to nest.
What size entrance hole is best for bluebirds to keep out swallows?
A 1 1/2 inch entrance hole is ideal for bluebirds and will deter larger birds. While a Tree Swallow can fit through this size, the smaller opening gives bluebirds a slight advantage in defending the nest.
How far apart should I space my bluebird houses to minimize competition?
Spacing bluebird houses at least 100 feet apart is recommended to reduce competition. Bluebirds are territorial and this distance allows them to establish distinct territories. More distance may be needed in areas with high swallow populations.
Is it legal to remove a swallow nest from a bluebird house?
The legality of removing a swallow nest depends on the specific species and local laws. Most native birds in the United States are protected under the Migratory Bird Treaty Act, which prohibits the destruction of nests containing eggs or young. It’s crucial to consult with your local wildlife authorities before taking any action.
What should I do if swallows have already built a nest and laid eggs in my bluebird house?
If swallows have already built a nest and laid eggs, it is generally best to leave the nest undisturbed until the young have fledged. Disturbing a nest with eggs or young can be illegal and harmful to the birds.
Can bluebirds and swallows coexist peacefully in the same area?
Bluebirds and swallows can coexist in the same area, especially if there are ample nesting opportunities and foraging resources. Providing multiple nest boxes and maintaining diverse habitats can help reduce competition.
Are there any plants I can grow to attract bluebirds but not swallows?
Attracting bluebirds primarily involves providing food sources like native berries (e.g., dogwood, serviceberry, blueberries) and insects. Planting native plants that attract insects will benefit bluebirds. There aren’t specific plants that deter swallows. The key is to create a diverse habitat that supports bluebirds and other beneficial wildlife.
Do swallows return to the same nest box year after year?
Swallows are known to return to the same nesting areas year after year. Tree Swallows are particularly faithful to their breeding sites, often using the same nest box for multiple seasons.
How can I prevent house sparrows from taking over my bluebird house?
House sparrows are an invasive species that can aggressively compete with bluebirds for nesting sites. The most effective method of control is consistent monitoring and removal of house sparrow nests before they lay eggs. House sparrow traps can also be used. Do not encourage house sparrow nesting near your bluebird boxes.
What materials should I use to build my own bluebird house?
Untreated cedar is the best material for building a bluebird house because it is weather-resistant and durable. Other options include pine and redwood. Avoid using treated wood, which can be toxic to birds. Ensure proper drainage and ventilation.
What months are bluebirds and swallows most likely to nest?
Bluebirds and swallows typically begin nesting in the spring, with the nesting season lasting from March to August, depending on the geographic location. Tree Swallows often arrive slightly earlier than bluebirds, potentially giving them an advantage in claiming nesting sites. Monitor your birdhouses closely during these months.