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Cynthetiq · 09-08-2004, 09:20 AM

we have peregrine falcons here in NYC

good for keeping down the pigeon population.

http://www.nyc.gov/html/dep/html/news/falcon.html

Quote:

Today, Peregrine Falcons are making a comeback in New York City. We currently know of 16 falcon couples, or 32 falcons total, that live year-round in unique places throughout the City such as on top of bridges, church steeples and high-rise buildings. While this comeback has been years in the making, it is possible that the goal of restoring the falcon population will finally be achieved, due to efforts of people like DEP scientist, Chris Nadareski.

In the 1970's, the Peregrine Falcon, or Falco peregrinus from the Latin for wandering, was placed on the endangered species list. Their populations across North America were depleted during the 1950's and 1960's, primarily because of the introduction of many chemicals, such as organochlorine pesticides. These toxic substances would harm the reproductive cycle of the falcon, preventing it from being able to hatch healthy young. To prevent the species from becoming extinct, falcons were bred in captivity and released into the wild, primarily through the efforts of Dr. Tom Cade and The Peregrine Fund, an international organization dedicated to the restoration of populations of birds of prey. In New York State, the Department of Environmental Conservation (DEC) is responsible for developing a Statewide Recovery Plan for the Peregrine and remains in charge of all regulatory oversight. Barbara Loucks of DEC's Endangered Species Unit is responsible for overseeing New York States Peregrine Program. Since 1992, DEP and DEC have worked cooperatively in implementing objectives of the recovery plan by developing and protecting nesting sites. In time, Chris, working for a team of scientists at The Peregrine Fund and DEC, helped to re-introduce falcons through a process called 'hacking' where young peregrines are released into the wild and learn to fly and hunt without help from adult birds. For about 8 weeks, he and other scientists would work around the clock to monitor and feed hacked fledglings until they adapted to their environment and learned to hunt for themselves.

In 1983, the first two falcon pairs moved to New York City. Today, there are 16 falcon territories; 12 of which have attempted to nest during the 2002 season so far. The falcons nesting season generally begins in the late winter or earlier with a selection of the nest site. The resident falcons generally stick to the nest boxes provided year after year as do the mated pairs. Immediately following in late winter or early spring the adult pair begins its courtship rituals. These rituals are often quite spectacular with aerial acrobatics of circling and diving at tremendous speeds by the male falcon called the tiercel. It is during this time that the male bonds with the female to prepare for copulation and egg-laying. Eggs are generally laid about every 36 hours from late February to early April. The average clutch size is four but in New York City, we often see 5 eggs. It takes about 30 days for the eggs to hatch and Chris normally bands the young in the nest at age 3 ½ weeks (old enough to accept the band and too young to jump out of the nest). By 5 ½ to 6 weeks the nestlings are ready to jump off the ledge for its maiden or first flight. From the first flight for about 8 weeks after, the young will remain dependent on the adults for protection and food. During the 8 weeks the young will begin as awkward fliers to accomplished aerialists who will be ready to catch its own meal. During the autumn when many birds migrate to warmer climates, the young falcons may stay in NYC or migrate down the Atlantic Coast. It is during this first year of independence that the young birds have to overcome numerous hazards to survive.

Why would a falcon couple want to nest in New York City? There are three outstanding reasons.

First, there is plenty of food for the falcon in the City. A falcon eats birds and the City has a plentiful bird population including pigeons, starlings, blackbirds, flickers, blue jays, and other birds that live in the area or fly through during the migratory season - when birds fly south to find warmer weather. It has been documented that the City falcons have eaten over 75 species of avian prey over the past 15 years of data collection. By collecting feathers, bones and pellets (a regurgitated capsule of undigestable bone and feather), cast by the falcons around the nest site, a City bird's diet can be identified . Information collected on the falcons diet has been used to determine the potential types of environmental contamination that are found in the food chain of the birds. These contaminants, such as chemicals found in pesticides or lead (mostly from paint chips of lead-based paints) have been found in the fleshy tissues of dead birds and unhatched eggs of the falcons through laboratory analysis by DEC's Wildlife Pathologist, Ward Stone. Chris submits all dead falcons and unhatched eggs annually to Mr. Stone to continue the monitoring of enrivonmental heatlh.

Second, the City reminds a falcon of its natural habitat. Falcons historically have lived on high cliffs over spacious areas ideal for hunting. A falcon will sit extremely still and watch its prey until it flies into an open area such as those over a river or the tree lines in a park. The falcon will dive down onto its prey at speeds ranging from 99 to 273 miles per hour (according to Tom Cade's summary of studies in his book "The Falcons of the World"). A City bridge or skyscraper provides a great deal of open air space and a unique perch for hunting.

Third, falcons and New Yorkers respect each others' privacy. The cooperation and understanding of New Yorkers is essential to the falcon's comeback in the City. As long as we do not try to feed falcons or treat them as pets or disturb their nesting and feeding areas, there is nothing for New Yorkers to fear. Instead, with patience and a pair of powerful binoculars, we can enjoy watching the beauty of these birds in flight.

Even though falcons live in the City all year long, Chris's involvement with them becomes most active in late winter and early spring when eggs are hatched. When a falcon is between 3 and 4 weeks old, Chris puts on his protective gear, climbs up into the nest area, and bands the foot, or tarses, of each young falcon. This is a very dangerous task since nests are often in high and precarious locations, such as on a bridge girder or on a skyscraper's window ledge. The process is doubly dangerous since adult peregrines can be angered by humans interfering with their nest. Many times, falcons will dive and attack, with Chris as the target, cutting him with their talons (finger-like sharp claws). Undaunted, Chris will finish the banding and monitor the nest from a distance - for the next several weeks, until the young falcons learn to fly and leave the nest, and at other times during the year until the falcon pair lays new eggs and start the cycle over again.

The banding process is not dangerous for a falcon, since their feet do not grow much after their first 4 weeks and the bands do not get in the way of their daily activities. Two bands are attached permanently for identification purposes. One band tracks the falcon locally, while the other is a band for the U.S. Fish and Wildlife Service that serves as a long-term record of the falcon. The bands help to track birds and provide information, such as where they travel and how long they live, that scientists use to learn how to better support the falcon population. At the time of banding, the young also get a physical examination to make sure they are healthy. After this brief process, the nestlings are returned to the nest, much to their parents' relief.

While Chris does all of the banding work in the City, the falcon project is a result of cooperation between the City, State, and federal agencies, environmental groups like The Peregrine Fund and the New York City Audubon Society, the owners of the places where falcons nest, wildlife rehabilitators in New York State and New Jersey, and the general public. For example, the City Triborough Bridge and Tunnel Authority and The Port Authority of New York & New Jersey grants Chris permission to make his annual bridge climb to reach one of the falcon nests. He also needs to make sure that people working near the nest know what preventative measures to take to avoid injury to the workers or the falcons. Chris works with community groups to foster awareness and cooperation around the nesting sites. Since falcons don't build real nests, Chris and personnel at the facilities that host the falcons construct nesting boxes for the falcon pairs. These nests are complete with small gravel used to cushion eggs, protective edges to prevent eggs and young birds from falling out of the nest, and perching bars from which the falcons watch their prey.

Public assistance through observations of nesting behaviors and retrieving young falcons that get into trouble during maiden flights (May and June annually) continue to enhance the chances of falcon survivorship through the City of New York. Over the years, many falcon volunteers have retrieved injured or dead birds from the streets and window ledges of the 5 boroughs. Recently, during the winter of 2002, we received an injured falcon, from Brooklyn, previously banded at the Riverside Church in 1995. The falcon rescuer from the general public called the City's CACC rescue unit who delivered it to the Animal Medical Center in Manhattan for emergency service. At that time, the veteraninary staff radiographed (x-rayed) the bird to find a pellet hole in the right wing. The bird was shot by a BB-pellet. Chris then brought the bird to a wildlife rehabilitation center in Morristown, New Jersey called the Raptor Trust. It was here, with the help of Len Soucy and staff, that the adult tiercel was rehabilitated for release back to the City.

The goal of banding falcons is to understand how they live, help them continue their population growth and, eventually, have them removed from the New York State endangered species list. With the help of biologists like Chris and the support of City residents, we hope to make this goal a reality.