The peregrine falcons of Nebraska

By Paul A. Johnsgard

During the 1930s and 1940s, there were about 500 pairs of peregrines in the United States, including about 210 active nests in the eastern states and 250–350 nests in the western U.S. Additionally, the arctic peregrine, a tundra-nesting race, consisted of perhaps 150 pairs that nested in high latitudes from Alaska to Greenland. Over all of their range the birds typically nested on steep cliffsides, and because of this need for tall cliff nesting sites, there are no firm historical nest records for Nebraska, although evidence exists for possible breeding having occurred near Fort Robinson, in 1903.

By 1960 the peregrine’s North American population had crashed, mostly as a result of the effects of the introduction of post-World War II pesticides, especially DDT. DDT enters the falcon’s system through its consumption of poisoned prey, especially insect-eating birds, interfering with the hormones regulating a female peregrine’s reproductive system. As a result, she lays soft-shelled eggs that might be crushed by the incubating bird or that otherwise fail to hatch. The peregrine falcon population had reached critically low numbers in North America by 1970, when it was listed as nationally endangered. It was among the species to be added to the initial list of nationally endangered species when the Endangered Species Act was enacted in 1973, thus becoming eligible for federal research and population recovery efforts.

It was not uncommon during the late 1960s to walk across the University of Nebraska’s Lincoln campus and see dead and dying songbirds after DDT had been sprayed to try to control summer mosquito populations. The publication of Rachel Carson’s book “Silent Spring” in 1962 had alerted the country to the dangers of using such pesticides, but it took another decade of political and legal fighting before the sale and use of DDT in the U.S. was finally prohibited. During the late 1960s, I published a community columnist piece in the Lincoln Journal, pointing out the health perils to both humans and wildlife of using DDT. I very soon received an irate letter from one of the vice presidents of Vesicol, the largest American producer of DDT and other agricultural chemicals, telling me that the substance is completely harmless and that to prove it he sprinkles a teaspoonful of DDT on his breakfast cereal every morning! I didn’t reply but have often wondered how much longer he survived.

The increasing construction of high-rise buildings in many U.S. cities has had an unexpected benefit for peregrines. Evidently accepting the idea that skyscrapers are nothing but artificial cliffs, peregrines began nesting on their highest ledges as their numbers slowly began to increase in the late 1970s. Cities not only provide such potential nest sites but also an abundant supply of urban birds, such as rock pigeons and starlings, and freedom from predators of newly fledged birds, such as great horned owls and golden eagles. Buildings that are at least 10 stories high are selected; such heights are apparently the lowest that the birds will accept. Nests located at lower heights are perhaps too low for a newly fledged peregrine to launch from and gain enough flight speed to achieve aerial maneuverability control before crashing to earth.

By the late 1980s a major restoration program was underway for the peregrines, largely planned and funded by The Peregrine Fund, a nonprofit group centered in Boise, Idaho. This program involved monitoring and protecting active aeries in the western mountain states and reestablishing nesting birds in both western and eastern states by captive breeding and release (“hacking”) programs. By the early 1990s over 3,000 captive-bred peregrines had been released in the U.S., and there were about 100 active breeding pairs in the east, about 20 in the Midwest and about 400 in the west. The peregrine’s population has since continued to improve, and it was removed from the nationally endangered list in 1999.

In Nebraska, efforts to establish peregrines in the state began in 1998, when seven juvenile birds were hacked at Woodmen Tower, then the tallest building in Omaha. Of these, five fledged, but none returned the following year. In 1989, five more falcons were hacked, including two males named Woody and Sky King.

In 1992, Woody returned to the tower and mated with Windy, a female that had hatched during 1990 in Des Moines, Iowa. The pair produced three young, Ariel, Zenith and Skywalker, becoming the first peregrines known to have been produced by a wild pair in Nebraska. During the following year, Windy produced three infertile eggs.

In 1993, Woody’s broodmate Sky King returned to Omaha, mated to a female (Kay Cee) that had hatched the previous year in Kansas City, Mo. In 1994, they produced a single fledged chick, Sokol, and in 1995 another chick was produced, but it died before being named.

In 1996, Zeus began his amazingly long reign in Omaha. He had hatched in Rochester, N.Y., during 1994. In 1996, he and his mate, Minnie (who had hatched in Winnipeg, Manitoba. in 1994), nested on the Woodmen Tower, producing four chicks and fledging two of them. In 1997, four more chicks hatched, but all died before fledging. In 1998, five young were fledged, and in 1999, four more were successfully reared.

By 2001 Zeus had acquired a new mate, Amelia, hatched in 1999 in Cedar Falls, Iowa. He had begun courting her the previous year, when she was still too young to breed. The new pair successfully hatched four chicks in 2001, but none survived to fledging. However, during the next three summers, they fledged a total of eight young birds, including at least two every year.

Zeus acquired his third mate in 2006, a female (Hera) of unknown age and origin. In 2006, they managed to fledge four youngsters, followed by four more in 2007. The entire 2008 brood died before fledging, but in 2009, four females were fledged, and in 2010, two males and two females were reared. By then about 50 peregrines had been successfully reared on the Woodmen Tower.

The story for Lincoln is similar. I had long believed that Lincoln’s capitol might support breeding falcons and had once suggested to city officials that a hacking program should be initiated. The question of hacking costs and the problem of interfering with the external appearance of the building made that proposal unsuccessful. However, during the summers of 1990–1993, a male peregrine frequented the capitol, acting territorial and courting females. In 1991, the Nebraska Game and Parks Commission installed a nesting platform on the 18th floor, just below the capitol dome. Several females were seen around the capitol over several years between 1992 and 1997, but no nesting attempts occurred. The nest box was removed from 1998 to 2002 during the capitol’s renovation but was reinstalled in March 2003.

By May 2003 a pair of peregrines had taken territorial possession of the capitol. The male (band 19-K) had hatched in Des Moines, and the female (Angel) had originated in Minneapolis. The pair produced two eggs that year, but neither hatched. During the following year, a pair was also present, but no eggs were produced. After adding a protective roof to the nest box and installing a television monitor in February 2005, the box quickly attracted a pair of falcons. The male was the same one as had been present in 2003, but the female (A/*Y) was a new mate that had hatched in Winnipeg. The male chick that they fledged that year was appropriately named Pioneer. Pioneer was not only the first of the capitol’s fledged peregrines but also a testimony to the efforts of the late John Dinan, the Nebraska Game and Parks biologist who had worked so hard to make the project a success.

In 2006, the same pair produced three fledged chicks, Willa, Bess and Sterling, named for Willa Cather, Bess Streeter Aldrich and J. Sterling Morton. In 2007, they successfully raised four, Boreas, Notus, Eurus and Zephyrus, after the four winds of Greek mythology. In 2008, four eggs were laid, but the nest failed. In 2009, with a newly designed nest box installed, the pair raised four more chicks, named after Nebraska rivers, the males Platte and Calamus and the females Nemaha and Niobrara. The chicks produced by the capitol pair have annually been given names on the basis of an annual free and open contest, in which anybody may suggest possible names.

Most recently, in 2010, four eggs were laid, of which three (two males and a femle) hatched and fledged. In the annual chick-naming contest, they were given highly appropriate names for aerial hunters: Alnitak, Alnilam and Minataka, after the three bright stars in the belt of the hunter constellation Orion.

In recent years, the Woodmen and capitol falcons have become tourist attractions, and it is possible to see the daily activities of both pairs during the nesting season through monitors in the two buildings. They may also be seen via Internet connections from the Woodmen of the World building or the website of the Nebraska Game and Parks Commission.

Besides the convenience of seeing the family on television, one may watch their activities from the capitol grounds with the aid of binoculars or get very limited views from the observation deck on the capitol’s 14th floor. Throughout spring and summer the adults engage in spectacular flights as they hunt for birds to feed themselves and their young. Often the prey are rock pigeons that are so common in the city, but the falcons have been found to take a wide variety of songbirds. There are even accounts of the birds using the lights illuminating the capitol after dark to attack nocturnal birds such as nighthawks.

During their chases, and especially their vertical dives, peregrines attain air speeds far in excess of any other species. By taking trained peregrines into airplanes and skydiving with them, it has been possible to make accurate estimates of peregrine air speeds during their full-out dives. In two such experiments, speeds of 183 and 242 miles per hour were calculated! This blinding-fast speed means that nothing below them has a chance of outflying a peregrine. However, it also must require incredibly fine flight control and skill to home in at that speed on a bird far below that may be flying up to 50 miles per hour at a nearly right angle to the plummeting falcon and which is frantically trying to avoid being hit.

It seems especially satisfying that our state capitol is now the adopted home of the peregrine falcon, one of the world’s most spectacular birds. And it is symbolically appropriate that they are nesting below the capitol dome’s iconic thunderbird design, symbolizing the Native Americans’ belief that the thunderbird will bring life-giving rain to our beautiful land. Our peregrines may not be bringing us our recently abundant rain, but their presence is giving us enormous pleasure.

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