ADOPT A FALCON
A Falcon is any of several species of bird of the genus
Falco, such as the Peregrine Falcon which are raptors or
birds of prey.
These birds have thin, pointed wings, which allow them to
dive at extremely high speeds. Peregrine Falcons, the
fastest birds on Earth, are said to have reached stoop
speeds of up to 200 mph.
Other falcons include the Gyrfalcon, Lanner Falcon, and the Merlin. Some small insectivorous falcons with long, narrow wings are called hobbies, and some which hover as they hunt for small rodents are named as kestrels.
The traditional term for a male falcon is a "tiercel". It is so called because it is roughly a third smaller than the female.
The technique of hunting with captive birds of prey is known as falconry.
The falcons are part of the family Falconidae, which also includes the caracaras, Laughing Falcon, forest falcons, and falconets.
In February 2005 the Canadian scientist Dr Louis Lefebvre announced a method of measuring avian IQ in terms of their innovation in feeding habits. Falcons were named among the most intelligent birds based on this scale.
The Peregrine Falcon (Falco peregrinus), sometimes formerly known in North America as Duck Hawk, is a medium-sized falcon about the size of a large crow: 38-53 cm (15 to 21 inches) long. The English and scientific species names mean "wandering falcon", and refer to the fact that some populations are migratory. It has a wingspan of about 1 metre (40 inches). Males weigh 570-710 grams; the noticeably larger females weigh 910-1190 grams.
Peregrine Falcons live mostly along mountain ranges, river valleys, and coastlines and increasingly, in cities. They are widespread throughout the entire world and are found on all continents except Antarctica.
Peregrines in mild-winter regions are usually permanent residents, and some birds, especially adult males, will remain on the breeding territory. However, the Arctic subspecies migrate; tundrius birds from Alaska, northern Canada and Greenland migrate to Central and South America, and all calidus birds from northern Eurasia move further south or to coasts in winter.
Peregrine Falcons feed almost exclusively on birds, such as doves, waterfowl and songbirds, but occasionally they hunt small mammals, including bats, rats, voles and rabbits. Insects and reptiles make up a relatively small proportion of their diet. On the other hand, a growing number of city-dwelling Falcons find that feral pigeons and Common Starlings provide plenty of food.
Peregrine Falcons breed at approximately two to three years of age. They mate for life and return to the same nesting spot annually. Their courtship includes a mix of aerial acrobatics, precise spirals, and steep dives. Females lay an average of clutch three to four eggs in a scrape. Scrapes are normally made on cliff edges or, increasingly more so, on tall buildings or bridges. They occasionally nest in tree hollows or in the disused nest of other large birds. The laying date varies according to locality, but is generally from February to March. The females incubate the eggs for twenty-nine to thirty-two days at which point the eggs hatch.
Thirty-five to forty-two days after hatching, the chicks will fledge, but they tend to remain dependent on their parents for a further two months. The tercel, or male provides most of the food for himself, the female, and the chicks; the falcon, or female stays and watches the young.
Because of their high metabolic rates, Peregrine Falcons must consume more food in proportion to their size than most animals. To be efficient flyers, the digestive system of birds has to be both as light as possible and as efficient as possible. The need to keep weight as low as possible also means that, except perhaps prior to migration, there is a limit to the amount of fat the Peregrine Falcon can store. The respiratory system is also unique; the Peregrine Falcon maintains a one-way flow of air so that it can breathe while flying. This system is much more efficient than the more common two-way flow of air. Birds have two relatively small lungs, where gas exchange occurs, but the lungs are augmented by bellows-like air sacs, where no gas exchange occurs. These air sacs keep the lungs perpetually inflated, even when the bird is exhaling. The Peregrine Falcon also has cones in its nostrils to help regulate breathing at high speeds. Its circulatory system also needs to be exceptionally strong, because flying takes lots of oxygen. A bird's heart beats much faster than the human heart does, approximately 600-900 beats per minute.
The average life span of a peregrine falcon is approximately eight to ten years, although some have been recorded to live until slightly more than twenty years of age.
The Peregrine Falcon became endangered because of the overuse of pesticides, during the 1950s and 1960s. Pesticide build-up interfered with reproduction, thinning eggshells and severely restricting the ability of birds to reproduce. The DDT buildup in the falcon's fat tissues would result in less calcium in the eggshells, leading to flimsier, more fragile eggs. In several parts of the world, this species was wiped out by pesticides.
Peregrine eggs and chicks are often targeted by thieves and collectors, so the location of their nest should not be revealed, unless they are protected.
Wildlife services around the world organized Peregrine Falcon recovery teams to breed them in captivity.
The birds were fed through a chute so they could not see the human trainers. Then, when they were old enough, the box was opened. This allowed the bird to test its wings. As the bird got stronger, the food was reduced because the bird could hunt its own food. This procedure is called hacking. To release a captive-bred falcon, the bird was placed in a special box at the top of a tower or cliff ledge.
Worldwide recovery efforts have been remarkably successful. In the United States, the banning of DDT eventually allowed released birds to breed successfully. There are now dozens of breeding pairs of Peregrine Falcons in the northeastern USA and Canada. Many have settled in large cities, including London Ontario and Derby, where they nest on cathedrals, skyscraper window ledges and the towers of suspension bridges. About 18 pairs nested in New York City in 2005.
These structures typically closely resemble the natural cliff ledges which the species prefers for nesting locations. During daytime the falcons have been observed swooping down to catch common city birds such as pigeons and Common Starlings. In many cities, the Falcons have been credited with controlling the numbers of such birds, which have often become pests, without resort to more controversial methods such as poisoning or hunting.
In Virginia, state officials working with students from the Center for Conservation Biology of the College of William and Mary in Williamsburg successfully established nesting boxes high atop the George P. Coleman Memorial Bridge on the York River, the Benjamin Harrison Memorial Bridge and Varina-Enon Bridge on the James River, and at other similar locations. Thirteen new chicks were hatched in this Virginia program during a recent year. Over 250 falcons have been released through the Virginia program.
In the 53-mile long New River Gorge of West Virginia, another program is underway to re-establish populations by transfering "bridge chicks" from Virginia, Maryland, and New Jersey to special nesting boxes mounted on the high cliffs.
The Peregrine Falcon was removed from the U.S. Threatened and Endangered Species list on August 25, 1999. In 2003, some states began issuing limited numbers of falconry permits for Peregrines due to the success of the recovery program.
In the UK, there has been a good recovery of populations since the crash of the 1960s. This has been greatly assisted by conservation and protection work led by the RSPB. Peregrines now breed in many mountainous and coastal areas, especially in the west and north. They are also using some city buildings for nesting, capitalizing on the urban pigeon populations for food.
The Gyr Falcon (Falco rusticolus), also spelled Gyrfalcon (The 'g' is pronounced as "j" in "jar"), is a large bird of prey. This species breeds on Arctic coasts and islands of North America, Europe and Asia. It is mainly resident, but some birds disperse more widely after the breeding season, or in winter. Its male is sometimes called a Gyrkin or similar and is smaller than the female. The name comes from French gerfaucon, and is written in mediaeval Latin as gyrofalco. The first part of the word may come from Old High German gîr ( modern German Geier) = "vulture", referring to its size compared to other falcons. The Gyr Falcon is a bird of tundra and mountains, with cliffs or a few patches of trees. It lays 2-6 eggs on a cliff ledge nest. This is the largest falcon, at more than 60cm in length with a wingspan up to 130cm, similar to the Common Buzzard. The female is larger than the male. This species is like a large Peregrine Falcon in general structure, but broader-winged and longer-tailed than the Peregrine. It usually hunts by horizontal pursuit, rather than the Peregrine's stoop from a height, and takes bird and small mammal prey such as Ptarmigans and lemmings. Plumage is very variable in this species, although typically adults have slate-grey back and wings, and young birds are browner. Sexes are similar. Greenland Gyr Falcons have white plumage, flecked with grey on the back and wings. Other geographical forms are varying intensities of grey in coloration: the Icelandic form is the palest, and Eurasian forms are considerably darker. In medieval times, the Gyr Falcon was considered the king's bird. Due to its rarity and the difficulties involved in obtaining it, in falconry the bird was generally reserved for kings and nobles. Very seldom was the time when a man of lesser rank could be seen with a Gyrfalcon on his fist. In falconry Gyr Falcons are very expensive to buy, and thus owners and breeders of gyrfalcons tend to keep them secret to avoid theft. They tend to fly long distances, and falconer may fit a radio-tracker to aid recovery.
The Lanner Falcon (Falco biarmicus) is a large bird of prey that breeds in Africa, southeast Europe and just into Asia. It is mainly resident, but some birds disperse more widely after the breeding season. The scientific or Latin name biarmicus comes from the fact that the Lanner has a sharp raised point located on its beak's edge about half the distance from the end of the beak to the corner of the mouth. Thus it is doubly armed with two cutting weapons on its beak. Ironically, nearly all falcons have this same type of beak structure. It is a bird of open country and savannah. It lays 3-4 eggs on a cliff ledge nest, or occasionally in an old stick nest in a tree. Lanner Falcon is a large falcon, at 43-50cm length with a wingspan of 95-105cm. It is like a large Peregrine Falcon in general structure. It usually hunts by horizontal pursuit, rather than the Peregrine's stoop from a height, and takes mainly bird prey in flight. European Lanner Falcons have slate grey or brown-grey upperparts, but the African birds are a paler blue grey above. The breast is streaked, but the belly is whitish, unlike Saker Falcon. Sexes are similar, but the browner young birds resemble Saker. However, they never show the all-dark thighs of the larger species. The call is a harsh "wray-e". In falconry its male is called a lanneret. Lanner falcons are prized in falconry as an excellent 'first falcon'. Displaying a good nature sometimes lacking in more highly powered birds, what Lanners lack in hunting prowess they more than make up for in personality. Outstandingly manouverable, they use their large tails and relatively low wing loading to perform exceptionally to the lure and can take a range of small birds as prey. One of the few raptors to attack prey head on at times, their tactics of ambush and surprise make them entertaining birds for crowds to enjoy. Bred in captivity for falconry, their numbers are in something of a decline in Europe, though they remain relatively common in parts of Africa. Hybrids between Peregrines and Lanners are a popular choice for modern falconers.
The name kestrel is given to several different members of the falcon genus, Falco. Kestrels are most easily distinguished by their typical hunting behaviour which is to hover at a height of around 10-20 m over open country and swoop down on prey, usually small mammals, lizards or large insects. Other falcons are more adapted to active hunting on the wing. Kestrels require a slight headwind in order to hover, hence a local name of windhover for Common Kestrel. Their ability to spot prey is enhanced by being able to see ultra-violet which is strongly reflected by vole urine. Plumage typically differs between male and female, and (as is usual with monogamous raptors) the female is slightly larger than the male. This allows a pair to fill different feeding niches over their home range. Kestrels are bold and have adapted well to human encroachment, nesting in buildings and hunting by major roads. Kestrels do not build their own nests, but use nests built by other species.