Archive for July 13th, 2006
tedpack.org
The barn swallow is a slender, elegant bird. Its back, wings and tail are midnight blue, its breast and belly russet. The face is russet too, save for a black mask across the eyes; the male reminds me of a raffish bandit, wearing a sporty vest under his black tie and tails.
We have had a family of swallows return to our front porch for seven years now. The first year we watched with quiet wonder as they built their nest; when they came back the second year we were delighted, and now their return is just another miracle of Spring, like the daffodils. A nest shell will last two or three years before it crumbles. When it does the birds build a new one, one tiny daub of mud at a time, using straw and an occasional horsehair to hold it together. The shell is as big as a grapefruit and holds a warm inner nest. In our house the inner nest is made from stray feathers and dog hair. Our dogs start to shed their winter coats about the same time the swallows appear, so we brush them vigorously and put the hair out where the swallows can recycle it.
The swallows always put their nest on the back side of the 4×12 header beam. They couldn’t have picked a better place to build. The beam protects them from the wind, the height from stray cats, our roof from the rain and the stored heat of the day - we have a thick concrete porch - from the night’s chill. Their nest is invisible from the street, which keeps them safe from small boys with rocks and pellet rifles.
Our swallows arrive every year about Easter, give or take a fortnight, spend a while cleaning up the nest, then settle down to raise young swallows. After three weeks we can see the youngsters peeping over the edge of the nest, waiting for their parents to come back from their forays with a beakfull of bugs to eat. In three more weeks it’s time for flight lessons, from the edge of the nest to the porch light and back again, and then the teenagers move out to live on the telephone wires while the parents raise a second brood in the nest.
About the first week in September they head south. Roger Tory Peterson tells me barn swallows range from Alaska and northern Canada through most of the western United States in Summer, from southern Mexico to Argentina in winter. While their seasonal range is known, no one knows the exact migration pattern; the Argentine swallows may make epic flights to Alaska every year, or they may just lolly-gag up to Arizona and let someone else go to Alaska. We like to think there is a family somewhere in Argentina who wait for “their” swallows to show up every November.
While the birds are in residence we take care not to slam the front door and try to walk past the nest quietly. Still, they twitter in alarm and fly away in great swooping arcs as soon as we open the front door, if the weather is good. This proves they are wild birds, not half-tame overstuffed park pigeons. If it is dark, cold or raining they just hunker down in their nest and pretend we can’t see them, which proves they aren’t stupid, either.
They have a nice sense of the conventions. Last spring I went out to take some pictures of the youngsters, who had fledged but hadn’t started flying. The best portraits are taken at eye level, so I stood on a kitchen chair in the corner farthest from the nest. The parents took off and the rest of the family ducked out of sight, both with cries of alarm. They weren’t really frightened; they just knew that wild birds have to be photographed from a blind.
Hoping their sense of propriety was stronger than their knowledge of camouflage, I found a tall, narrow cardboard box, cut a hole in one side, and tried again. The box stopped at my waist and the hole was a good six inches square. To anyone brighter than the bulb we leave on all night in the bathroom I looked like a man with a 35 millimeter camera and a box on his head. It was a bird blind however, and the swallows let me stand on my chair and take pictures, knowing we were both following the conventions.
That was our year of the problem child. Each spring we become accustomed to the “someone is on our porch” alarm calls. About a week after the portrait session I heard true alarm cries when the youngest bird tried to fly a bit too early. He had managed to flutter out of the nest to the ground, but couldn’t do the return leg. I noticed a distinct difference in the “too-kweet, too-kweet” calls. The difference was in intensity, not phrasing, like the difference between our dogs’ “someone is walking past the house” bark and their “the horses have broken the fence again” bark. When I went out to look Junior scuttled into the shrubbery. I, mindful of getting my scent on his body, used a pair of 4×6 index cards to pick him up and put him back into the nest.
I used the cards the next three times he fell out of the nest, then decided if his parents could fly within three feet of my head while I dumped him back into the nest, they wouldn’t be surprised if he smelled like me, so I used my bare hands. Over the next week Junior kept trying to fly and I kept listening for the alarm call, putting him back when needed. I noticed he got farther from the nest as time went on.
One Saturday morning when I was in the kitchen, watching through the window, he took off from the nest, determined to test his wings. They worked just fine for gliding, but he couldn’t turn and he couldn’t flap. As I watched he glided straight as an arrow for the pickup truck parked in the front of the yard, dropping about a foot for every twelve feet of forward motion. He hit the passenger side door head first. I went out yet again and put him back into the nest. Some human children are like that; bound and determined to do things they aren’t quite ready for. Their parents can usually see the truck parked in the glide path, so to speak. Sometimes their parents can’t get out the front door in time to stop them from hitting the truck, and sometimes they see it coming but figure it won’t kill the kid and it might teach him a lesson, so they let him crash into it. Our problem child finally graduated to adult birdhood as a competent flyer.
The birds are remarkably clean; one square of cardboard, changed weekly, catches most of the mess, and a short session with the hose once a month does the rest. In this respect, since they feed and water themselves, they are easier to keep than hamsters, and more fun. Besides, as I tell visitors, each little black and white squiggle used to be 50 mosquitoes.
The birds’ advantages far outweigh their disadvantages, especially for a family with young children. We have used them to encourage our youngest to eat her dinner, for instance. The first two years we pointed out what daddy bird was doing (stuffing half-chewed bugs into little gaping beaks) and played our own version of “Daddy Bird and Baby bird”. The next year we played without the example, since they had grown out of that stage. Saying goodnight to Mr. Bird and Mrs. Bird is a regular part of our going-to-bed ritual. We’ve used them as springboards for discussion on topics as diverse as trust and responsibility, migration, the difference between seasons in the northern and southern hemispheres, survival strategies in nature, and the roles of parents and children. Even my wife, who majored in zoology at Michigan, has learned things frrom our swallows. She didn’t know barn swallows had names until our youngest asked about it. Last year we had Daniel and Donna; this year we’re hosting Elmo and Esmerelda, oddly enough.
The parents and their teen-agers are swooping through the dusk outside the window as I finish writing this, catching their dinner. Our power goes out whenever we have a good storm, we’re lucky to get a dial tone ten times in a row, and our children don’t have sidewalks, but there are times when it is good to live in the country.
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July 13th, 2006
amnh.org
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.
References
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
July 13th, 2006
mitra-bisnis.biz
BERBAGAI cara dilakukan orang untuk memancing walet agar mau bersarang dan betah di “rumah walet”; mulai dari meletakkan telur, piyik atau kotoran walet, membuat sarang imitasi, menyemprot dengan parfum pemikat, memasang kayu khusus tempelan hingga memanf
Soundsystem and CD? Are you kidding? Apakah walet-walet disuruh nyanyi di panggung kemudian direkam ke dalam keping CD (compact disc), lantas CD-nya dijual di toko-toko kaset/CD? Memang mirip-mirip seperti itu, tapi tidak persis demikian.
Pada dasarnya soundsystem di sini digunakan untuk menghasilkan suara walet yang dihasilkan dari CD player yang berisi rekaman suara-suara burung tsb, sehingga diharapkan burung-burung walet sebenarnya akan terpikat dengan suara “temannya” itu sehingga ikut bergabung dan membuat sarangnya di sana.
Menurut situs http://waletsoundsystem.com, Indonesia disebut-sebut sebagai penghasil sarang walet terbesar di dunia, 99% rumah penangkaran walet yang tersebar di sentra-sentra penangkaran di Sumatera, Jawa Barat, Jawa Timur, Jawa Tengah dan Kalimantan memakai soundsystem untuk memancing burung waletnya masuk dan berkembangbiak di rumah penangkaran.
Pemasangan soundsystem walet di tempat-tempat penangkaran, menurut situs ini, terbukti efektif untuk memancing walet masuk dan bersarang ke dalam rumah walet. Selain berguna memancing walet masuk, soundsystem walet juga berguna untuk meningkatkan produksi sarang walet, karena dengan adanya suara-suara walet yang diputar terus menerus selama 24 jam dari soundsystem tsb maka walet-walet lebih betah untuk bersarang.
Survei yang dilakukan situs ini membuktikan bahwa dengan menggunakan soundsystem pemanggil walet tingkat keberhasilannya jauh lebih besar dibanding sistem tetas telur, dengan perbandingan 3 bulan : 3 tahun. Hasilnya sangat menggembirakan, hanya dalam beberapa bulan rumah-rumah walet yang baru berdiri sudah dihuni walet.
Cara Kerja
Soundsystem pemikat walet dirancang untuk mengeluarkan suara berfrekuensi tinggi yang jernih dan nyaring. Suara yang dihasilkan soundsystem ini berasal dari CD yang berisi suara-suara walet. Suara-suara inilah yang nantinya berfungsi memancing walet untuk masuk ke dalam rumah walet, sekaligus membuat walet betah dan bersarang di gedung yang diperuntukkan untuknya.
Salah satu yang menentukan dalam teknologi ini adalah keping CD-nya. Saat ini beragam CD walet dipasarkan di pusat-pusat penjualan sarana produksi walet, ada yang khusus berisi suara walet memanggil, tengah pacaran, dan cericit piyik atau campuran ketiganya. Semua suara walet tsb diperlukan untuk memancing walet.
Karena suara walet untuk masing-masing tempat berbeda satu sama, maka disarankan suara walet yang diperdengarkan berasal dari suara khas walet daerah setempat. Sebagai gambaran, di Sei Rampah, Sumatera Utara cericit suara waletnya panjang dan teratur, berbeda dengan dari Lubuk Pakam, suara waletnya pendek tapi dengan irama yang cepat. Namun jangan khawatir sudah banyak pembuat CD walet yang menghasilkan suara mencakup semua karakter suara walet.
Komponen soundsystem pemikat walet sebenarnya banyak tersedia di pasar-pasar elektronik, sehingga kita pun bisa merakitnya sendiri, namun bagi yang tidak mau repot dan takut gagal, tinggal sediakan biaya ekstra karena sudah banyak perusahaan yang mengkhususkan diri membuat alat pemanggil walet ini.
Dengan bantuan soundsystem ini, frekuensi suara walet yang dihasilkan bisa diatur seasli mungkin. Sebagai contoh, situs Soundsystem Walet memperkenalkan satu unit pemikat walet yang memiliki 2 tombol pengatur frekuensi yaitu middle (menengah) dan high (tinggi). Tombol middle untuk vokal dan high untuk frekuensi tinggi sehingga suara tweeter sebagai pemancing dapat terdengar oleh burung walet hingga radius 2 km.
Alat itu juga dilengkapi 4 tombol pengatur volume. Masing-masing tombol dihubungkan tweeter. Kapasitas maksimal 40 tweeter / tombol yang dirangkai secara paralel. Dengan begitu pemilik bisa leluasa men-set tweeter pada setiap lantainya.
Soundsystem ini pun sudah auto play sehingga akan aktif secara otomatis ketika dialiri listrik. Unit ini mampu menerima aliran listrik 160 volt - 240 volt dan hemat karena hanya berdaya 100 - 150 Watt. Selain itu juga dilengkapi auto repeat yang akan secara otomatis memutar CD dari awal lagi bila masa putar habis. Sehingga cocok digunakan di daerah terpencil.
Sebagai output secara langsung, digunakan tweeter karena suara yang dihasilkan speaker mini ini cocok dengan bunyi siulan walet yang berfrekuensi tinggi. Ada 2 jenis tweeter yang biasa dipakai yaitu yang dipasang di dalam ruangan dan di luar ruangan untuk lubang masuk (pemancing). Selain cara pemasangannya harus benar, tweeter luar ruangan sebaiknya dipasang di pojok atas lubang masuk. Tweeter luar dipilih jenis double flat dengan berfrekuensi tinggi dan volume besar. Sementara tweeter untuk di dalam cukup yang berukuran kecil namun jumlahnya harus banyak. (Dede Suhaya / walet-soundsystem.com)
July 13th, 2006