why do young barn owls need feathers
Bird feathers, in general, have to be one of the most amazing creations in nature. The flight feathers of wings and tail enable birds to flyБnot glide like flying squirrelsБbut fly powerfully from one end of the globe to the other. Down feathers insulate birds from cold. Contour feathers keep the birds dry in the rain. Powder-down feathers disintegrate into a talcum like dust that birds use to condition the other feathers. Each feather is a work unto itself: Radiating out from the central shaft that runs up through the middle of the feather, individual vanes also contain barbs that hook over the next vane, and those barbs in turn have barbules that hook on to the barbs. This sophisticated arrangement makes for a very lightweight yet resilient structure. And when these various vanes and hooks become disorganized, a mere pull of a beak through the feather puts them all back together again. Beyond these functions, feathers hold the brilliant, defining colors of sexual attraction. Since birds can see colors, various pigments evolve in feathers to make birds, especially the males, more attractive to lure a mate. But not all colors are pigments produced by the feathers. The reds in flamingos come from the foods they eat. And blues cannot be created inside the feathers, so they are created by the structure of the feathersБthe soft brilliant blues of jays and buntings and the metallic sheen of purples and greens on grackles and blackbirds are created by infractionБillusory colors that work just the same.
Beyond displaying color to impress the opposite sex, the feathers of doves, pigeons, hummingbirds, manakins, and nighthawks are used in flight to whistle, hum, and boom to create БsongБ that attracts potential mates. The feathers of owls have other,
owlish purposes. These are refinements brought about by darkness and stealth and the quiet of night. As anyone should know who has ever heard a duck or a pheasant take off, feathers in flight create a lot of sound. Songbirds that eat insects and seeds have little need to be stealthy. The same is true for almost all birds. Even the leading edge of the wing of a hawk through air creates a discernible sound as do the stiff tail feathers cupped to slow down before landing. But hawks use high speed and surprise to capture their prey in full daylight. Owls hunt in the quiet of night where their favorite prey, rodents, utilize their hearing to detect potential predators. Since rodents have poor vision but relatively good hearing, owls rely on being quieter than a whisper to capture their food. This is accomplished by their special feathering. While the leading edge of a hawkБs wing is sharp and defined (and thus noisy), the leading edge of an owlБs wing contains a serrated, comb-like structure that breaks up the air as it passed over the wing.
This soft combing of the air results in almost no sound being produced. In addition, the feathers of the wings, body, and tail of owls are wider and rounder than those of other birds and, to further reduce sound, they are cloaked in a soft, velvety covering of tiny feathers that also soften their passage through air. The result is almost totally silent flight. Try using a tape of owl calls to call in common owl species in your area. You will notice that, if you do not happen to glimpse the owls arriving, the first thing you will hear will be their singing in response to the tape. They will arrive soundlessly, like ghosts. Their prey also never hears their arrival and must rely on their poor eyesight under dim conditions to detect danger from owls. The combination of silent flight and excellent hearing creates a perfect nighttime predator in owls. Tyto alba Barn Owls have large round heads with white heart-shaped faces and dark eyes. Their wings and back are covered with buff-colored feathers. The feathers on their chests and underneath their wings are white with black or brown speckles. Their legs are long and featherless.
Barn Owls are slim medium-sized owls, measuring 14-20 inches long with a wingspan of 43-47 inches. Barn Owls weigh 1-2 pounds. Barn Owls are able to fly in total silence due to their fringed feather tips that break the flow of the air at the trailing edge of their wings. Their hooked beaks and sharp talons help them catch their prey, which they can locate in absolute darkness with their exceptional hearing. One ear is placed higher on the head than the other, enabling the Barn Owl to sense the direction and distance of a sound. Barn Owls, like other owls, also have excellent vision. Mice, gophers, voles, shrews, small birds, insects, fish and crustaceans make up the diet of the wild Barn Owl. At Cosley Zoo, the Barn Owl receives quail, rats, and mice. Because of their physical limitations, the raptors at Cosley Zoo are not fed live prey. Barn Owls mate for life. Females lay a clutch of 3-6 eggs. The eggs are laid one at a time every few days over 2 or 3 weeks. Since each egg needs to incubate for 32-34 days before hatching, the hatching of the eggs is also spread out over a 2 or 3-week interval. At about 3 weeks of age, the owlets are able to eat by themselves the food their parents provide. By two months of age, the young are completely independent. Barn Owls raise 2-3 broods per year.
The Barn Owl can be found in trees, abandoned burrows and buildings, and old farm machinery left in fields. Its preferred habitat is temperate forests and grasslands. Barn Owls hunt at night in open areas and fields and cover a large area, sometimes flying up to 3 miles looking for food. In the wild, Barn Owls have an average life expectancy of 2 years. In captivity, they can live to be 15-18 years old. Barn Owls are at the top of the food chain and are considered important components of the ecosystem. They control the pest populations of small animals such as mice. The Barn Owl is currently on the Illinois Threatened Species List. Its status was upgraded to БThreatenedБ from БEndangeredБ in 2014. Barn Owls have a special toe called a pectinated claw that has ridges and is used for cleaning the birdsБ feathers. Instead of the БhootБ associated with most owls, the Barn Owl makes a hissing noise. Owls donБt chew their food! They swallow it whole or in chunks and regurgitate a pellet containing bones, fur, feathers, and other material they are unable to digest. A baby owl is called an owlet. Barn Owls have been called БnatureБs perfect mousetrapБ because of their large appetite. One Barn Owl family of two adults and six owlets can eat more than 1,000 rodents during a three-month period!
- Views: 20
why does my horse stomp his foot
why does a peacock spread its feathers
why does a peacock fan its feathers
why do wading birds have long legs
why do they call it a bald eagle
why do they call a bald eagle a bald eagle
why is my chicken losing her feathers