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Nature's fastest flier increases in population
The peregrine falcon has one of the most extensive natural distributions of any bird in the world, limited only by high elevations, extreme heat, and extreme cold. It is found on all continents except Antarctica. The American peregrine falcon breeds in Mexico, the United States and Canada. Peregrine falcons are protected under the U.S. Migratory Bird Treaty Act. Permits are issued pursuant to federal regulations to qualified individuals and institutions breeding raptors for falconry and conservation purposes. Falconry is an ancient sport, practiced in China before the year 2000 B.C. At one time, the type of falcon an Englishman was allowed to own marked his rank. Notable falconers and enthusiasts include Frederick the Second, William Shakespeare and Marco Polo. Although peregrines have a high mortality rate, they have been known to live as long as 15 years. Chicks eat an incredible amount of food, doubling their weight in only six days. They will be 10 times birth size at three weeks. Peregrine falcons are monogamous and breed in the same territory or area their entire lives. There are exceptions, such as when one mate dies or is replaced by a stronger individual. Sexual maturity occurs during the second year of life, followed by a month of courtship. In the spring, three or four eggs are laid. Incubation takes 33 days. Two or three chicks usually hatch and fledge in about 42 days. After fledging, young falcons are dependent on their parents for food until they learn to hunt, which takes about a month and a half. Peregrine falcons lay their eggs in "scrapes," which are shallow indentations they scratch out with their talons in the soft earth on the floor of their nests. Peregrine falcons typically nest on ledges and in small shallow caves located high on cliff walls.
How do they capture their prey? Peregrine falcons are aerial predators, feeding on live birds and an occasional bat, which they capture in mid-air. Peregrine falcons often hunt in tandem, alternately diving on their prey until it is caught. What was the historical size of the American peregrine falcon population? The historical status of the American peregrine falcon is not known, but it was probably never common, even when compared to other birds of prey. The limited historical data suggest a best estimate of 3,875 nesting pairs. The decline of the American peregrine falcon population began in the 1940s and was most pronounced during the 1950s. Its decline continued through the 1960s into the early 1970s throughout most of its range. By the time biologists realized the magnitude of the American peregrine falcon decline, the population was only about 12 percent of what it had been prior to the introduction of modern pesticides. The use of DDT as a pesticide during the 1940s, 1950s and 1960s resulted in a precipitous decline of peregrine falcons in North America. During this period of DDT use, eggshell thinning and nesting failures were widespread in peregrine falcons, and in some areas, successful reproduction virtually ceased. As a result, there was a slow but drastic decline in the number of peregrine falcons in most areas of its range in North America.
How many American peregrine falcons are there today? There are between 2,000 and 3,000 breeding pairs of American peregrine falcons in Canada, Mexico and the United States. What's the status of the peregrine falcon now? Thanks to the increase in peregrine falcon population, the U.S. Fish and Wildlife Service was able to remove the species from the federal list of threatened and endangered species effective August 25, 1999. The peregrine falcon will be monitored for several years to ensure that it no longer needs the protection of the Endangered Species Act. If necessary, the species can be added back to the list in the future.
Sources: U.S. Fish & Wildlife Service, www.fws.gov |
The peregrine falcon belongs to the genus "Falco," which is characterized by long pointed wings.
How fast can a peregrine falcon fly?
In level flight, the normal speed for peregrines is about 40 to 55 miles per hour. In a stoop (dive)
peregrine falcons can attain speeds in excess of 200 miles per hour as they attack their prey.
How many American peregrine falcons were there when the bird was first placed on the
endangered species list?
The eastern population of the American peregrine falcon was gone and the populations in the west
had declined by as much as 90 percent below historical levels. By 1975, there were only 324
known nesting pairs of American peregrine falcons.
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