This year, 12 baby peregrine falcons have hatched on Boulder open space land and fledged -- meaning some of their adult plumage has come in and they've learned to fly -- which makes this the most productive year for the birds since monitoring began in 1984.

The number of peregrine fledglings on Boulder Open Space and Mountain Parks land got a boost two years ago when a new pair of birds moved into the area, choosing to make their nest on the Back Porch, a rock formation in the Flatirons, and bringing the total number of nesting peregrine pairs to four.

Last year, those four pairs of peregrines produced 11 fledglings, said Will Keeley, a wildlife ecologist for the city.

Boulder open space employees keep a keen eye on the birds with the help of a troop of volunteer raptor monitors, who spy on the birds using binoculars or spotting scopes during the breeding season.

"It's a world-class program," said Keeley, who noted that the open space department has fielded several phone calls from other areas seeking to replicate the program's success.

About 65 volunteers work to track the nesting sites of about 15 pairs of raptors, including peregrines, prairie falcons, golden eagles and bald eagles. Volunteers have designated days of the week when they commit to spending several hours observing the birds and noting when eggs are laid, when chicks hatch and when the young raptors first leave the nest.


"It's a really unique opportunity right in our own backyard," said 11-year-old Benjamin Johnston, who participates in the program with his parents and his brother Nick, 14. "It was amazing watching (the peregrines') devotion to nesting and raising young -- just watching the nestlings grow into powerful, strong fliers."

The Johnstons decided to become raptor monitors, in part, because of Benjamin's love of photographing birds.

"I've been watching birds for maybe three or four years and photographing birds," he said. "We were talking to a ranger one day about animal tracks, and I was sharing my photos with her and she mentioned the raptor program. It was a perfect fit."

Over the last months, Benjamin and his family have gotten to know the pair of birds they were assigned to monitor and the four fledglings they raised.

"They each had really different markings," he said. "Some had brown diamond breasts, some had streaks, some were a creamier, lighter color and some were really dark."

Over the winter, the local peregrines will head south, returning again in the spring to breed, and peregrines often return to the same area to nest each year. The young birds that survive -- only about one in four will make it to adulthood -- will seek out new nest sites in the future.

Peregrine falcons were federally listed as an endangered species in 1970, when the pesticide DDT had caused their populations to dwindle to just a few hundred nesting pairs in the United States.

But the birds have recovered, and in 1999, they were removed from the endangered species list, though they are still being monitored by the federal government. Local observations by raptor monitors go into the reports that the city of Boulder issues to fulfill the monitoring requirements.

"Peregrines were almost extinct," said Laura Johnston, Benjamin's mom. "To be able to watch their behavior and their nesting so closely is a rare opportunity."
