The pair had been spotted several times, but it wasn’t clear if they were passing through or nesting until a recent Pennsylvania Game Commission investigation.
After observing the birds flying around downtown Reading, the commission’s peregrine falcon coordinator headed to the top of the county courthouse.
Once there, Dr. F. Arthur McMorris and county employees found the heads of other birds that had been eaten by the predatory peregrines, which are considered an endangered species in Pennsylvania.
“They eat up here all the time,” said James Moorman, county facilities manager.
But McMorris didn’t find any evidence that the birds were trying to nest on the roofs of the courthouse or the nearby county services center.
So McMorris headed over to The Madison building at Washington Street and Madison Avenue.
When McMorris emerged onto the roof, the female peregrine suddenly appeared and flew around excitedly.
“She hadn’t done that when we were at the top of the courthouse,” McMorris said.
Based on that behavior and photographs of the birds mating on a ledge high up on a side of The Madison, McMorris concluded the peregrines have likely selected the top of that building to try to lay eggs.
“They’re going to at least try here,” McMorris said.
If they’re successful, the pair might be here raising young until mid-July.
“It’s very exciting,” said Laurie J. Goodrich, senior monitoring biologist at Hawk Mountain Sanctuary near the Schuylkill County line. “With their aerial maneuvers, they’re one of the most exciting raptors that a person can see in the wild. Hopefully, they’ll settle in.
“We have not seen peregrines nesting in this area, around central southeastern Pennsylvania, for a long, long, long time.”
Peregrines’ traditional habitat in this region has been near cliffs along rivers.
“The falcons have figured out very quickly that cities have a lot of cliff-like habitat and they have a lot of prey: pigeons and other birds, that are easily targeted for feeding,” Goodrich said.
Peregrines have been nesting in Harrisburg, Philadelphia, Wilkes-Barre and New York City in recent years.
A pair was recently spotted in Allentown.
Peregrines usually scrape to form nests. On a rooftop, it might just be a depression in a portion of gravel.
The situation leaves The Madison’s property manager, Rosemary P. Hemmer, with a most unusual tenant.
“This is new for us,” she said.
Unfortunately, there may come a time when maintenance crews will have to be on the roof because the building rents roof space to two companies with antennas there, she said.
Also, some of the building’s heating and air-conditioning systems are on the roof and could need maintenance, she said.
“We want to be respectful of the wildlife,” Hemmer said. “It’s kind of a neat thing. On the other hand, we can’t keep people from conducting business.”
Hemmer said she’s going to talk with building staff about how to approach their rooftop guests.
That both birds are flying around means they don’t yet have eggs, McMorris said.
If they do have eggs, one bird will stay with the eggs while the mate hunts, he said.
It’s important to determine if they nest because state officials would like to tag any young that are produced to aid population counts and track migratory patterns, McMorris said.
Some county employees said they’ve been observing peregrines around the courthouse for the last few years, but there is no documented evidence of a nesting.
Some county employees said they saw peregrines teaching smaller peregrines to fly last spring, but male peregrines are significantly smaller than females and can be mistaken for young.

“I think we have to take these reports with a grain of salt,” McMorris said. “I’m not dismissing it, but I’d rather go by reliable information.”
There are no known records of peregrines nesting in Berks.
In 2006, 15 pairs of peregrine falcons nested in Pennsylvania.
All but two were on manmade structures such as buildings and bridges.
That was a record number since more than 50 years ago when certain pesticides, which have since been banned, began interfering with peregrines’ ability to reproduce.
Before the pesticide use there were 44 known nesting sites in Pennsylvania in the 1940s.
Only one was on a manmade structure — Philadelphia City Hall.
“The population is increasing, but we have a long way to go,” McMorris said.
•Contact reporter Jason Brudereck at 610-371-5044 or jbrudereck@readingeagle.com.