Once nearly extinct, peregrine falcons return to nest in Acadia

A peregrine falcon chick being banded by a park wildlife biologist in 2010. U.S. NATIONAL PARK SERVICE PHOTO

Peregrine falcons are territorial and defensive. The once nearly extinct birds will dive-bomb, screech at and even strike something that threatens them and their chicks. They nest high up in on the eastern face of Champlain Mountain in Acadia National Park. There, they give birth to and rear their chicks in hollow depressions on the mountain’s soaring cliffs. Their exposed nesting site serves as a platform to defend their young from predators and pursue small birds and other prey.

During nesting season, from June through mid-August, Acadia has an observation site where visitors can sit on a couple of stone benches and gaze at up at the Precipice Trail cliffs and see peregrine falcons, whose wings span just over 3 feet — the height of a preschooler — glide through the air. They can look through a 20-60x80mm spotting scope and pick out the blue-gray and white feathered falcons’ nests. They can watch the yellow-taloned peregrines plunge from their perches, called scrapes in pursuit of food or to warn off predators. The fastest creature on Earth, the birds’ diving speeds have been clocked at over 200 miles per hour.

Based in the Downeast region, Alan Howell Parrot once trained hunting falcons for Middle Eastern nations’ royal families and high-ranking officials. The smuggling of the remarkable birds and other practices prompted him to found the Union for the Conservation of Raptors. His work to conserve wild falcons was featured in the 2010 documentary “Feathered Cocaine.”

“They’re beautiful. They’re the apex predator of the sky,” Parrot says. “Anybody who handles or looks at these birds, if they have any common sense at all, will fall in love. If you want to inspire a young generation of people to care about wildlife, just show them a falcon and they [will be] hooked on wildlife conservation.”

To protect the nesting falcons, Acadia closes off the Precipice Trail until mid-August, but the park staffs the observation site daily from 9 a.m. to noon. Monday-Friday. Park rangers are stationed at the Precipice Trail Head to answer visitors’ questions and help them view the raptors from afar. Several hundred people visit the site daily.

Acadia National Park Ranger Patrick Kark peers through his binoculars at the Champlain Mountain’s east-facing cliffs where a pair of peregrine falcons are in residence and raising four chicks. OUT & ABOUT PHOTO BY MAGGIE TROVATO

Through a partnership with Friends of Acadia, a nonprofit conservation organization, Acadia National Park Ranger Patrick Kark says a computer monitor, attached to a camcorder, also is available for providing live, up-close footage of the peregrine parents and chicks on the Precipice Trail Cliffs.

In Acadia, the chance to see these powerful avians in action contrasts starkly with the species’ extinction in the Northeast half a century ago. The peregrines were added to the federal Endangered Species List in 1970. Banned in 1972, the widespread use of dichloro-diphenyl-trichloroethane (DDT), a pesticide sprayed on crops to control insect infestations and combat mosquitoes, started in the post-World War II era. Contaminated by DDT, insects such as mosquitoes were consumed by sparrows and other small birds. In turn, peregrine falcons consumed the smaller birds. This chain reaction led to unhealthy egg production and decimated the peregrine falcon population, according to The Peregrine Fund.

Besides the use of DDT, Parrot says other contributing factors to the peregrines’ demise was an increase in the great horned owl population — a predator of falcons — as well as the extinction of the passenger pigeon, which the falcons preyed upon.

Besides the U.S. Environmental Protection Agency’s ban on DDT, the National Park Service and other federal agencies and nonprofit groups mobilized to restore the peregrine population. They created “hacking” sites where falcons could be raised, released and protected in a viable environment. Chicks were hatched in a laboratory and raised in captivity in a “protective wooden box with a view of the area [the chicks’ natural surroundings]” until their wings were strong enough and they could be released, according to the National Park Service.

The hacking program proved successful in Acadia. One laboratory chick, named Ganesh, returned in 1987 after being released the previous year. Ganesh claimed the Precipice cliffs as his own. To ensure adequate air space for the young falcon to fly, the practice of hatching and raising chicks in captivity ceased. Year after year, Ganesh returned to the park. He and his mate raised their fledglings on the Precipice Cliffs in 1991.

In 2017, an adult peregrine falcon keeps close watch as chicks are lowered for banding by a park wildlife biologist. U.S. NATIONAL PARK SERVICE PHOTO

“Although this is a relatively big cliff,” Kark explained, peregrines require and seek lofty places where they have enough room to nest, patrol and hunt. “Only one pair of falcons would ever nest on this.”

In 1999, peregrine falcons were removed from the federal endangered species list. While their comeback has been hailed, the birds still are considered vulnerable.

“Ever since 1991, we have had an apparent attempt to nest here on the cliffs,” said Kark, who hails from Littleton, Colo. In the summer, he serves as a supervisory park ranger in Acadia’s Visitor Experience and Education division and sometimes works over the winter.

Like 2021, Acadia has three breeding pairs of peregrines this season. One pair inhabits the Precipice Cliffs while the other two pairs spend the season at Jordan Cliffs overlooking Jordan Pond and Valley Cove on the western side of Mount Desert Island. The Precipice Cliff pair’s four chicks recently were banded to track their movements.

“We went up there… knowing that there were two [fledglings] in there,” Kark said. “It’s really hard to know exactly what’s going on up on that cliff. [We] found four. There are four fledglings up on that cliff right now.”

At Acadia, three is about the maximum number of breeding pairs that will nest in the park. That’s because the birds prefer high cliffs facing eastward (for the sunshine) and need a lot of space for their nesting sites.

To view this year’s peregrine family, the Precipice Trail viewing site is located off Park Loop Road in Bar Harbor. For more info, visit https://www.nps.gov/acad/learn/nature/peregrine-falcons-in-acadia.htm.