Unveiling the Barn Swallow Habits Nesting, Feeding, Migration
The Barn Swallow with its distinctive long forked tail makes it one of the easier North American swallows to identify.
When flying, the feathers are swept back and form a single long point behind the bird.
One sure sign of summer is when you see them flying back and forth to an open barn or outbuilding where they build their nests.
Barn Swallows spend more time in the air than almost any other land bird.
A friend to farmers, these swallows are on an endless search for insects throughout the season.
Barn Swallow
Barn Swallow Call
What Barn Swallows Look Like
Barn Swallows measure 5 1/2 to 7 inches in length with pointed wings and a deeply forked tail.
The bill is very short. Dark blue-black above with a dark rusty throat. The rest of the underparts are buffy or pale rusty.
Females are similar with shorter outer tail feathers than males.
The young juvenile swallows are similar to the adults, but have paler underparts and shorter outer tail feathers.
Mating Habits Do Barn Swallows Mate for Life?
Mating habits of Barn swallows include engaging in aerial displays during courtship, which can include diving, swooping, and chirping. Males will also display tail feathers to females.
Pairs are formed quickly once they've reached the breeding grounds. Within 2 weeks of arriving, pair bonds will have been made.
Barn Swallows are generally monogamous, with males mating with a single female. However, studies show females will copulate with other males.
Rebecca Safran, when a Cornell postdoctoral researcher in ecology and evolutionary biology at the Cornell Laboratory of Ornithology, found that female Barn Swallows would breed with males that had darker breast and belly feathers while paired with another male.
Interestingly, 50 percent of male Barn Swallows care for and feed at least one chick fathered by another male. Sometimes the whole clutch is from another male Barn Swallow.
Paired males will aggressively defend the small area around the nest and guard their mate against other males that might attempt to copulate with her.
Although rare, males sometimes will pair with 2 females, but parental care will be given to the first clutch.
Pairs stay together through the breeding season and sometimes will pair in consecutive seasons. However, Barn Swallows do not mate for life.
Barn Swallow Nesting Habits
Barn Swallow nesting occurs primarily in June and July. Both the male and female build the nest.
Working in the morning, Barn Swallows will make up to 1,000 trips to collect mud and grasses before nest completion
What a Barn Swallow Nest Looks Like
This is one of the few times you can see them on the ground collecting mud and feathers for their mud swallow nest.
Although these birds originally nested in caves and on cliffs, they now use more man-made structures such as barns and the overhangs of decks and patios.
You can offer an artificial nest to try to get them nesting where you want.
The nest is a cup of mud pellets lined with grass and feathers, located under the eaves of buildings, resting on a beam or some projection in barns, under bridges, and in culverts.
Barn Swallow Preening Feathers
The female lays 3 to 8 white eggs that are spotted with reddish brown beginning 1 - 3 days after nest completion.
The eggs are incubated by both adults with the female incubating longer. Only females have a brood patch.
The eggs will hatch after 14 to 16 days of incubation. The young will leave the nest in 18 to 23 days.
Like other Swallows such as Purple Martins, unmated male Barn Swallows will sometimes kill the young of other pairs to mate with the female.
Two broods a season may be attempted. Barn Swallows return to the same nest site each season and will make repairs to the old nest in order to reuse it.
| Barn Swallow Nesting Stats | |
|---|---|
| Eggs | 3 - 8 |
| Incubation | 14 - 16 days |
| Nestling Phase | 18 - 23 days |
| Broods | 1 - 2 |
A new nest will be built if no repairable nest is available. Removing the nest during the winter will not keep them from returning.
A barrier may have to be built to get them to change sites. Once they move on, the barrier can be removed.
If you do not want them nesting (they can be messy) on your house, you must not let them build their nest. Using some type of Swallow Deterrent.
You can remove their nest until eggs are laid. Once eggs are laid, the law protects them, making it illegal to interfere during the nesting cycle.
The image below shows what a Barn Swallows nest looks like with eggs inside.
Barn Swallow Nest and Eggs
The adult birds continue feeding the fledglings for about 1 week after leaving the nest.
When the young first leave the nest, they perch in the landing tree. For a short time, the adults will bring food to the young while perched in trees.
Later, the adults will pass food to them in flight, showing them how to catch flying insects.
Diet and Feeding Habits
Barn Swallows eat and feed their young flying insects caught on the wing.
During the breeding season, these birds will feed in pairs and fly at a low altitude, generally over fields and water.
You are most likely to see Barn Swallows following you as you mow large field areas. Swooping close to the ground and catching insects, the lawnmower or tractor causes to fly up.
Flying over water is where you may see both Purple Martins and Barn Swallows together. Just skimming the surface of the water to bathe or drink.
During the non-breeding season, they will feed in small, loosely formed flocks.
Birdwatchers can offer egg shells or oyster shells that the Swallows need for calcium and grit, which aid in digestion.
One of the best reasons to have these birds around is to help get rid of pest insects that bother us when we're enjoying the outdoors.
Habitat
The habitat of Barn Swallows is mostly open country and marshes, especially near barns, outbuildings, bridges, and culverts.
Since humans are developing more housing in what was once farmland, these birds can be found more and more nesting on house exteriors.
Barn Swallow Migration
Spring migration may start as early as February for Texas and California, but for the most part, April and May will be the peak period.
By August, Barn Swallows will begin forming migratory roosts and heading southward.
By September you'll be hard-pressed to see any around. Both the adults and young will migrate at the same time.
Primary wintering grounds for North American birds are Central and South America.
See Also:
Other Types of Swallows in the World
