Barn swallows are beautiful birds that many homeowners enjoy seeing around their property. These aerial acrobats dart and swoop through the skies catching insects on the wing. Their forked, pointed tail streamers and orange-red throats make them easy to identify.
You may be wondering if you can attract barn swallows by installing nest boxes. Here are the quick answers to some common questions:
Do barn swallows use bird houses?
Yes, barn swallows will readily use nest boxes, as long as the nest box meets their specific requirements.
What kind of birdhouse do barn swallows prefer?
Barn swallows prefer open nest platforms or cups. They do not use enclosed bird houses or nest boxes with perches. The nest platform should be approximately 6 inches across and 1-2 inches deep.
Where should I mount a barn swallow nest box?
Mount the nest box on the exterior wall of a barn, shed, porch, or other structure, under the eaves. Position the nest box 6-20 feet above ground. Face the opening away from prevailing winds and direct sun.
When should I put up nest boxes for barn swallows?
Put nest boxes up in late winter or early spring, before the swallows return to your area from migration. This gives them plenty of time to scout out the nest sites.
What is the best time to see baby barn swallows?
The optimal time to observe baby barn swallows in the nest is usually late May through July. The eggs hatch after about 15 days of incubation. The young fledge in around 18-23 days after hatching.
Do barn swallows reuse nests?
Yes, barn swallows will often reuse their mud nests from previous years. They simply refresh and reinforce the nest each breeding season. A nest can be used for up to 7 years!
How many broods do barn swallows have per year?
Barn swallows typically raise two broods per breeding season. The first clutch is usually 4-5 eggs and the second clutch may have 3-4 eggs.
Do barn swallows migrate?
Yes, barn swallows migrate each winter to warmer climates in the southern U.S., Mexico, Central America, and South America. They return to their breeding grounds in spring.
What do baby barn swallows eat?
Parent barn swallows feed their nestlings a diet made up almost entirely of insects. They capture flies, moths, beetles, crickets, grasshoppers, and other insects in flight and bring them back to the nest to feed the young.
Do barn swallows eat at bird feeders?
No, barn swallows do not visit bird feeders. They feed exclusively on flying insects that they catch in mid-air.
Are barn swallows protected?
Yes, barn swallows are protected under the Migratory Bird Treaty Act. It is illegal to harm, harass, or kill barn swallows, their nests, or eggs without a permit.
Can I touch baby barn swallows?
No, you should never touch nestlings or fledglings. Baby barn swallows can be injured or may become imprinted. Leave babysitting duties to the parents.
Do barn swallows attack humans?
Barn swallows are not aggressive toward people. They may swoop near or buzz humans that get too close to the nest, but they are simply defending their territory.
How do I keep barn swallows off my porch?
To discourage barn swallows from nesting in an undesirable area like a porch, install obstacles such as netting, screens, or sheet plastic early in the season before nest building begins.
When do barn swallows leave the nest?
Young barn swallows remain dependent on the parents for 1-2 weeks after fledging the nest. They follow the parents, begging for food. Gradually the young disperse and become independent.
Barn Swallow Identification
Let’s look more closely at the physical characteristics of barn swallows to help you identify these aerial acrobats.
Size and Shape
Barn swallows measure 5.5-7.5 inches in length with a wingspan around 12 inches. They have a slender, streamlined body shape built for fast and agile flight.
Plumage
Adult males have glossy steel-blue upperparts and a brick-red forehead, throat, and upper breast. The lower breast and belly are a pale cinnamon buff color. Females are similar but have a paler forehead and breast band.
Tail
Barn swallows are easily recognized by their unique, deeply forked tail. The tail streamers can be up to 5 inches long. These function as rudders during acrobatic aerial maneuvers.
Beak
They have a small, tapered beak that is black on top and reddish on bottom. The beak is ideally adapted for catching insects in flight.
Barn Swallow Behavior
Here are some interesting facts about the behavior of these energetic, social birds:
- Barn swallows are very social and congregate in large flocks, often with other swallow species.
- They migrate in huge mixed flocks that can number in the millions.
- Barn swallows are active and agile fliers. They catch all their prey on the wing.
- A barn swallow may log up to 500 miles in a single day during migration.
- Barn swallows communicate with a variety of twitters, chirps, and calls.
- Though messy, their mud nests are carefully crafted engineering masterpieces.
- Both the male and female work together to build the nest over 6-14 days.
- Barn swallows bathe frequently by skimming across water surfaces.
Barn Swallow Habitat
What types of areas do barn swallows prefer when looking for suitable housing?
- Open fields, meadows, farms, pastures
- Near lakes, rivers, ponds, other open water
- Open structures: barns, stables, sheds, garages
- Under bridges and highway overpasses
- Piers and docks, boats
- Porches, eaves, carports
Access to mud for nest building and open areas for foraging on flying insects are key.
Barn Swallow Diet
Here’s an overview of the barn swallow diet:
- Flies
- Moths
- Beetles
- Wasps
- Bees
- Ants
- Mayflies
- Dragonflies
- Grasshoppers
- Crickets
- Other flying insects
Barn swallows drink by skimming the surface of open water while in flight. They do not visit bird feeders or take food from humans.
Barn Swallow Nest Facts
The nest of the barn swallow is a remarkable feat of bird engineering. Here are some interesting facts about barn swallow nests:
- Made primarily of mud pellets, bound with grass and feathers
- Shaped into an open cup or bowl fixed to a vertical surface
- Lined with grasses, feathers, and sometimes paper scraps or plastic
- Male and female both gather mud and build the nest together
- Nest construction takes 6-14 days
- Nest interior diameter is about 6 inches
- Nest depth is 1-2 inches
- Nests are often reused for many years
- Old nests are refreshed with new mud each breeding season
Barn Swallow Nesting Facts
Here are some key facts about the barn swallow’s breeding and nesting habits:
- Clutch size is 4-5 eggs for first brood, 3-4 for second
- Incubation period lasts 14-16 days
- Only the female incubates the eggs
- Both parents feed the nestlings
- Young fledge 18-23 days after hatching
- May raise 2-3 broods per season from May-September
- Nestlings are fed flying insects caught on the wing
- Parents may travel up to a mile from nest to forage
Threats and Conservation
Although still common in many areas, barn swallow numbers have declined significantly in parts of their range over the last few decades. Here are some of the main threats they face:
- Loss of nesting habitat like old barns and bridges
- Increasing use of pesticides reduces insect prey
- Climate change may alter migration and breeding cycles
- Severe weather events can kill many migrating birds
- Collision with vehicles and infrastructure
Protecting remaining agricultural structures and wetlands, reducing pesticide use, and mitigating climate change are important conservation measures for barn swallows.
Fun Facts About Barn Swallows
- Barn swallows have one of the longest migrations of any North American bird, traveling thousands of miles annually between their breeding and wintering grounds.
- The barn swallow’s scientific name Hirundo rustica comes from the Latin word hirundo meaning swallow, and rusticus meaning rural or rustic.
- Barn swallows have special preen glands that secrete a red-colored oil they spread on their feathers to help make them waterproof.
- The male’s long outer tail feathers are thought to make him more attractive to females.
- Barn swallows molt all their flight feathers at once just after breeding season each year, leaving them flightless for about 3 weeks.
- Barn swallows feed while flying at speeds averaging around 25-30 mph.
- A group of swallows is called a “flight” or a “sweep”.
How to Attract Barn Swallows
Here are some tips to attract barn swallows to nest on your property:
Put up nest platforms or cups
Swallows need an appropriate nesting structure in place before they will take up residence in a new area. Install open, shallow cups or platforms on buildings, sheds, or under eaves.
Position nest sites appropriately
Make sure nest boxes are positioned 6-20 feet high on an exterior wall or beam. Face the opening away from wind and direct sunlight.
Erect nest sites before breeding season
Put nest cups or shelves up in early spring, well before the swallows return. This gives them ample time to scout out the new nesting sites.
Provide good foraging habitat
Barn swallows need open fields, meadows, or water for catching insects. Maintain areas of low vegetation that allow for easy prey capture in flight.
Avoid disturbance
Prevent people and pets from disturbing nests, especially during critical stages like incubation and when young are still in the nest.
Limit pesticide use
Reduce or eliminate insecticide use, as swallows rely on insects like flies, wasps, and beetles to feed their young.
Put up nests in suitable locations
Good spots include barns, stables, sheds, boathouses, docks, and highway bridges. Avoid patios, porches, or other high traffic areas.
Conclusion
Barn swallows are stunning aerialists that gracefully swoop and dart over fields catching insects. These social, migrant birds readily accept nest boxes, making them fun backyard visitors during spring and summer. Follow the tips above to successfully attract a breeding pair to your yard. Watching the parents work hard to feed their noisy broods of nestlings is a rewarding wildlife experience.