Nesting Habits of the Barn Swallow (Hirunda rustica)
On December 31, 2000, I went on an expedition up a ladder to examine two barn swallow nests. The nests are right outside my front door, on opposite corners of my family's front porch, here in Gallup, New Mexico. My original plan was to take the nests apart to see what items the swallows had used for their nests. But earlier in December, when I started to read about barn swallows, I learned how much work is put into the nests, and I decided not to take the nests apart. Instead, I examined the nests from a ladder.
The nests were 10 and 12 feet above ground and very near the ceiling of the porch. The only way to see inside the nest was to hold a mirror above it and examine its reflection. I also carried a ruler with me so that I could measure the nests. The first nest's depth was 11 centimeters. Its diameter was 10 centimeters. The circumference was 44 centimeters. At the top of the nest the walls were two centimeters thick. The thickness of the bottom of the nest was four centimeters. The second nest had a depth of 12 centimeters. The diameter was 11 centimeters. The nest's circumference was 36 centimeters. The nest walls were two centimeters thick. In both cases, the space between the ceiling and the nest was 9.5 centimeters. The measurements of the nests were very similar, which surprised me. The main difference is the difference in depth. I believe the older nest is deeper because it has been rebuilt over the course of five summers.
Materials used in the first nest include mud and straw. I also saw a hair or nylon thread woven into the nest. The second nest was made of mud, straw, and pebbles. I removed some additional material from the nest. On closer examination, I identified this material as two-pound fishing line, eight-pound fishing line and nylon broom material. Both nests were filled with straw and feathers, for bedding. The second nest I examined held a lot more feathers. It was almost overflowing with feathers! This may be because we have had birds living in this nest for several years longer than in the other one. I was still surprised, however, to see the feathers. Even though I knew that barn swallows line their nests with feathers, I had expected that wind, snow, and rain would have blown all the feathers away. I now know why the barn swallows chose the top of our front porch for their home. It is very protected.
The barn swallow nests remind me of the ancient Anasazi dwellings that are so common throughout the Southwest of the United States. These old stone-and-plaster homes were usually built in large hollows in cliffs. Protected from the rain, wind, and snow, the cliff dwellings have stood for 800 years. The barn swallows' nests are very much like this. They are so protected that the feather cushioning is still there several months, maybe even several years, after the swallows have left.
In spring my family and I look forward to the arrival of the barn swallows that visit us every year. For the past five years, the barn swallows have inhabited a mud nest in the corner of our front porch. Barn swallows first built this nest in the spring of 1995.
Each year, by late March or April, a pair of barn swallows arrives at our front porch. They always spend a few days fixing up the nest that is their summer home. This past summer, though, the barn swallows decided that they wanted a new nest and started to build it in a corner of our porch that is directly above our front door. My dad took apart the beginning of the new nest, but the swallows persisted. So we let them keep the new nest, too.
It took the swallows about a week to complete the nest, and soon after they had settled in, another pair came. These swallows fixed up the old nest and took up residence there. In past years, the swallows on our porch raised two sets of young during the summer. But this past summer, both couples raised three sets of young. Watching the adult swallows feed their young was very interesting because the swallows were not shy of us. Even though we couldn't see what it was that the parents were feeding their young, we could clearly see the wide, hungry beaks of the young as their parents deposited food in their beaks.
We have also observed a quirky animal behavior. One day, a few years ago, my dad turned on a world-beat CD that opened with a flamenco guitar song, "Twilight at the Zuq" by Jorge Strunz and Ardeshir Farah. With the front door open, the barn swallows could hear the music; they got excited and started flying up and down and in circles around our driveway and front porch. We use our CD player throughout the day, and no one in the family had ever observed them responding to music before, so we were surprised. Now, from time to time, we turn on that CD, The Best of World Music, just to see the barn swallows "dance."
Recently, I read that barn swallows migrate as far south as Argentina during the winter (Wetmore). Perhaps our visitors recognized the flamenco guitar as music that they hear during the winter and felt that they were indeed at home.
Barn swallows are found throughout the world, except Australia (Van Vleck). They can live six to nine years and keep the same mate all their lives. They also return to their nests each year, either the nest that they built with their mate, or the nest in which they were reared (Audubon). This is why we have had barn swallows return each year. The second pair of barn swallows that built a new nest last spring may have been children of our first swallows. Barn swallows are also swift and beautiful. John James Audubon writes in "The Barn Swallow":
"The flight of this species is not less interesting than any other of its characteristics. It probably surpasses in speed that of any other species of the feathered tribes, excepting the Humming-bird. In fact, barn swallows are strong and hardy birds that to fly to Argentina for the winter."
My mother used to wonder why we never saw the barn swallows in our backyard looking for worms in the grass, or for bugs in the garden. But I now know that barn swallows eat only flying insects, and do all their hunting on the wing. This means that they are welcome guests of farmers, as they consume insect pests (Line). The fact that barn swallows eat flying insects also explains their migration to South America for the winter. When they reach South America in August or September, they will find plenty of flying insects to eat.
A couple of times last summer, my family found small, shriveled-up baby birds dangling from a nest. In each case we assumed that the young bird had gotten trampled in the rush to have food dropped in its beak. We thought that one of the parents noticed the dead bird and pushed it out of the nest. In retrospect, that doesn't explain why the birds were still attached to the nest by a thin fiber.
Our swallows incorporate horsehair extensively into their mud nests. If this is not available, they use straw. I wouldn't recommend purposely providing horsehair because instances of birds becoming entangled in horsehair snares protruding from the nests have been reported. I have never witnessed this, but have found numerous loops of hair protruding from the mud nests (Van Vleck). I now know that swallows can get strangled in the long strings and hair that are sometimes incorporated into the nest.
Next spring, instead of trying to limit the barn swallows to one nest on the porch, we will encourage the barn swallows to nest as they please. I have even learned of some ways to help the barn swallows. In late March, we will set out a tray of mud to make nest repair easier on the birds. When building a nest, barn swallows carry more than 1,000 mouthfuls of mud to their nest. Setting out a tray of mud for them would speed up their task (Van Vleck). Another thing is to set out a birdbath. But instead of a traditional birdbath, I will put sticks over the top of the bowl. Putting sticks over the bowl for the bird to stand on protects the birds from frostbite (Cortright and Pokriots). I am looking forward greatly to the spring arrival of the swallows.
Audubon, John James. "The Barn Swallow" in Birds of America. Audubon's Multimedia Birds of America. Retrieved from the World Wide Web on December 9, 2000: http://employeeweb.myxa.com/rrb/Audubon/VolI/00076.html
Chipper Woods Bird Observatory. "Barn Swallow." Wild Birds Unlimited. Retrieved from the World Wide Web on December 9, 2000: http://www.wbu.com/chipperwoods/photos/barnswallow.htm
Cortright, Sandy and Will Pokriots. Making Backyard Birdhouses. New York: Sterling Publishing Co., Inc. 1996.
Cruickshank, Allan D. Cruickshank's Photographs of Birds in America. New York: Dover Publications, 1977.
Cunningham, Richard L. Fifty Common Birds of the Southwest. Tucson, Arizona: Southwest Parks and Monuments Association, 1990.
Farah, Ardeshir and Jorge Strunz. "Twilight at the Zuq." Recorded on The Best of World Music, Volume 2. New York: Putumayo World Music, 1993.
Goodfellow, Peter. Birds as Builders. New York: Arco, 1977.
Harrison, Hal H. A Field Guide to Western Birds' Nests. Boston: Houghton Mifflin Co., 1979.
Kavanagh, James, ed. The Nature of Arizona. San Francisco, California: Waterford Press: 1996.
LaTourrette, Peter. Photo, BARS-3: "Adult with Nesting Material." June 2000. North American Birds PhotoGallery. Retrieved from the World Wide Web on December 9, 2000: http://www.birdphotography.com/index.html
Line, Rebecca E. "Hirunda rustica: Barn Swallow." The University of Michigan Museum of Zoology. Retrieved from the World Wide Web on December 9, 2000: http://animaldiversity.ummz.umich.edu/accounts/hirundo/h._rustica$narrative.html
Nova Scotia Museum of Natural History. "Birds of Nova Scotia-Barn Swallow." Retrieved from the World Wide Web on December 9, 2000: http://museum.gov.ns.ca/mnh/nature/nsbirds/bns0261.htm
Van Vleck, Richard and Diane. "Barn Swallow." American Artifacts. Retrieved from the World Wide Web on December 9, 2000: http://www.americanartifacts.com/smma/per/b4.htm
Wetmore, Alexander. Song and Garden Birds in North America. Washington, D.C.: National Geographic Society, 1964.
White, Cheryl. "Winging it!" Audubon Society. Retrieved from the World Wide Web on December 9, 2000: http://www.rainieraudubon.org/wing/b-swallow.htm
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