Where do barn swallows nest?
What does a barn swallow’s nest look like?
What time of year do barn swallows nest?
What month do barn swallows lay eggs?
How long do barn swallows build nests?
How do barn swallows build their nests?
When do baby swallows leave the nest?
How many nests do barn swallows have?
Do barn swallows nest in the same place every year?
What do barn swallow eggs look like?
How Big Are Barn Swallow Eggs?
Do barn swallows use nest boxes?
Do Barn Swallows Nest in Backyards?
Barn swallow (Bumblebee) is one of the most widely distributed birds in the world. In fact, this highly successful bird may be the most widely distributed passerine, living on every continent except Antarctica.
Barn swallows are very vocal birds and can often be heard singing during their impressive acrobatic displays. Chances are, no matter where you live, barn swallows probably live near you.
In this article, we’ll dive into the details of barn swallow’s nesting behavior, habitat types, and many more interesting facts.
Where do barn swallows nest?
As the name suggests, barn swallows usually nest in buildings. They have been closely related to humans for thousands of years and are among the most studied birds. While many building-nesting birds are considered a nuisance, barn swallows are often encouraged because they deter insect populations. Barn swallows prefer open buildings near fields or farmland. They rarely choose to nest in rocky alcoves or cliffsides.
Barn swallow nests are incredible because they can be built on platforms or on vertical walls or beams. To secure the nest to the wall, Barn swallows the trowel and mixes it with grass, stems and other leaves. They then smear the mud on the walls and lay out their nests with soft leaves and feathers. The result is a mud cup nest that “sticks” to a vertical wall or beam.
Because they use dirt to build their nests, barn swallows often choose to nest near water. They are often found scooping up dirt with their small beaks, carrying it to their nests and spreading it carefully. They can make about 15 trips to and from the nest per hour. Both males and females build nests, but females usually do most of the structural work.
Of course, there is still a lot to learn about the nesting habits of these exotic birds!
Key Barn Swallow Nesting Facts | |
---|---|
nesting season | May to August |
nesting material | Trowel puree, mixed with grasses, stems, and other leaves |
nested type | Mud, platform or vertical on walls and beams |
nest location | Open buildings near fields or farmland |
brood number | two litters |
clutch size | 4 – 5 eggs |
egg color | Creamy or soft pinkish white with dark spots |
egg size | 20 x 14 mm |
egg weight | 1.9 grams |
incubation period | 16 – 18 days, mainly by women |
fledgling period | 20 – 22 days |
reuse nest | Yes |
using nest boxes | Yes |

Barn swallow feeding chicks in the nest

Barn swallows collect mud for nesting
What does a barn swallow’s nest look like?
Barn swallow nests are small, cup-shaped, and made of mud. They are usually built on ledges or in crevices. These unique bird’s nests are made of small clay particles that stick together to form a rigid three-dimensional shape. Once the clay cups are secured, the birds work together to spread grass and feathers indoors.
Barn swallows nest either on vertical or horizontal planes. Some research has shown that birds prefer to nest on horizontal platforms (which is traditional practice), but they are perfectly content nesting on vertical walls or beams with no underlying support.

Barn swallow feeding chicks in the nest
What time of year do barn swallows nest?
Barn swallows in North America and Central Europe usually start nesting in late April and early May, but in northern Europe they may wait until June or even later. In the south, barn swallows can nest as early as November. In Argentina, for example, nesting usually starts in late October, depending on the weather.
In hotter climates, barn swallows build their nests most of the year. These birds may raise as many as three broods, either sequentially or spread out throughout the year.

barn swallow in nest
What month do barn swallows lay eggs?
In North America and Central Europe, barn swallows usually lay their eggs as early as May. In northern Europe, such as Russia and Scandinavia, spawning is later, around June.
In the south, for example in Central and South America, spawning occurs earlier. Already in November in Argentina.

Barn swallow chicks waiting to be fed in the nest
How long do barn swallows build nests?
It takes about 14 to 20 days for barn swallows to build a nest, 14 to 16 days for young swallows to hatch, and 18 to 23 days for young swallows to leave the nest.
The couple may then raise a second litter shortly thereafter. If barn swallows raise a second nest, they will reuse the same nest about 50% of the time. Nests are often reused year after year. In general, barn swallows will build their nests for about two months.
How do barn swallows build their nests?
Barn swallows return from their migration and inspect many nesting sites in quick succession. These gregarious birds usually place their nests close to each other (at least about 30 cm).
A typical nesting site has good shade and protection from rain, which is essential to ensure the nest is not destroyed by inclement weather. Also, while barn swallows generally prefer to nest on hard, horizontal platforms, they will often nest on vertical walls or beams.
Once a nesting site has been chosen, the male and female work together to collect mud from a nearby pond, lake or watering hole. They then use their mandibles to scoop up the dirt and gradually apply it to the walls. Mud cups are about 10 to 15 cm wide with walls about 2.5 cm thick.

A pair of nesting barn swallows collecting dirt to build a nest
The main mud cup structure can take about two weeks to build. Once complete, the birds will begin to line the cups with grass and feathers, which can take about five days. The resulting structures are often very strong, and some have been reported to survive up to 30 years!
Barn swallows also typically have high reproductive success rates (70% to 90%), a testament to the dedication and ingenuity of these fine birds.

barn swallow nest
When do baby swallows leave the nest?
Young barn swallows usually leave the nest and fled after about 18 to 23 days, but they can leave after 14 days if the nest is disturbed.
After leaving the nest, the parents usually feed the bird for another 1 to 2 weeks before becoming fully independent.
How many nests do barn swallows have?
Barn swallows lay 1 to 3 broods per year. In Europe and North America, they are more likely to have one litter, and at most two. If the couple had a successful litter early in the season, they were more likely to have another litter.
In warm climates, barn swallows may disperse three broods over a period of 2 to 5 months.

A barn swallow is feeding a fledgling chick
Do barn swallows nest in the same place every year?
Barn swallows often reuse these nests for their second brood and next breeding season. One study showed that about 44 percent of barn swallows in the same colony reused the same nest in the second year after nesting.
When barn swallows return to their nesting grounds, they check the quality of the nest and check for any parasites or nesting insects. Prioritize a clean and hygienic nest. Some enduring nests last for years—one nest in Nebraska survived for about 30 years and was maintained with new mud every year.
What do house swallow eggs look like?
Eggs of barn sparrows are creamy white or soft pinkish white. They are slightly shiny and spotted with purple, red, brown or beige spots.

Barn swallow eggs inside the nest
How Big Are Barn Swallow Eggs?
Barn swallow eggs measure approximately 2 x 1.4 cm. The eggs are oval rather than oval and very small, weighing only 1.8 to 2.0 grams.
Do barn swallows use nest boxes?
Barn swallows are considered burrow nesting birds, using sheltered nest boxes installed below covered areas.
These types of nest boxes are best installed in open timber buildings, such as barns, close to farm fields or clearings. Barn swallows are excellent at keeping insect populations at bay.

Hungry barn swallow chick begging for food
Are barn swallows nesting in the backyard?
Barn swallows are sure to nest in any outbuildings, especially wooden barns and covered open buildings. However, they have also been observed securing their nests to steel structures.
If you have a tall, open structure in your backyard, swallows may be attracted to it. They prefer nesting sites that are sheltered from wind and rain.
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