Peregrine falcon expert Mary Hennen strapped herself into a safety harness and was lowered onto a ledge outside the 28th floor of University Hall, wearing a protective long-sleeve shirt and helmet to keep her safe.
“Not because it’s going to do me any good if I fall,” she said. “It’s [for] protection against the birds.”
Peregrine falcons are raptors that call some of Chicago’s tallest buildings home. Their beaks, claws and high-speed dives — reaching more than 200 miles per hour — let them hunt anything from small insects to medium-sized mammals. Those features help them defend their nesting sites, too.
Hennen, director of the Chicago Peregrine Program and collections assistant in the Field Museum’s bird division, visits the UIC site every year to take blood samples and band peregrine chicks, a process that involves putting small leg cuffs on the birds that help identify males from females. Bands also allow experts and peregrine enthusiasts to track dispersal and longevity.
Because of the bands, Hennen knows that the two chicks living on the UIC ledge belong to Nitz and Mouse, now in their fourth year of nesting at University Hall. The pair had a total of four eggs, but only two hatched. Both chicks, about 24 days old at the banding ceremony May 31, are males.
The information is important for experts, institutions and programs — like UIC and the Chicago Peregrine Program — that took part in restoring the species after it was classified as endangered in 1973.
“It was a result of DDT,” Hennen said. “Its byproduct affects calcium production in the females and inhibits it. So without the calcium, shells are too thin. The way that the adults incubate crushed it.”
Peregrines were bred in captivity and reintroduced to the Midwest using psuedo-cliff locations, such as University Hall, as nesting areas in the 1980s and ’90s.
“It shows that even in the middle of one of the biggest cities in the world, nature is at work,” said Provost and Vice Chancellor for Academic Affairs Susan Poser.
Pairs have nested outside of University Hall since 1986.
Falcons were successfully removed from the federal threatened and endangered species list in 1999, but they remained on the Illinois list. In 2004, they were reclassified from endangered to threatened. The species was removed from the list entirely last year.
“It’s a great program,” said Angela Yudt, associate vice provost for faculty affairs. She’s followed the UIC falcons for 23 years, since she was an undergraduate student. Her son, John Yudt, has followed them for five.
“They’re such extraordinary birds,” said Poser, a new falcon fan. She and UIC Chancellor Michael Amiridis held the new chicks and welcomed them into the UIC family at the banding event.
“It’s something that brings people together,” Poser added.
The chicks are expected to fly when they’re about 40 days old.
Watch the falcon family live on the UIC falcon cam.