Peregrine Falcons in Lakeview View Full Caption

LAKEVIEW — The downside of Dacey Arashiba's unexpected guests arriving outside his Lakeview apartment is he won't be grilling this summer.

"But the upside is that I get to have this amazing wildlife on my balcony," Arashiba said.

Indeed, on a recent Saturday morning, Arashiba showed a visitor a Peregrine falcon nestled in a hanging flower pot just outside the window of his 28th-floor apartment. The bird's companion had temporarily flown away 10 minutes earlier.

Last summer, the birds attempted unsuccessfully to stake their place outside Arashiba's apartment. Three weeks ago, the pair of Peregrine falcons returned to Arashiba's balcony overlooking Belmont Avenue.

"It's amazing, and kind of flattering, that they're back," he said.

Mauricio Pena says the birds were once endangered:

Arashiba first noticed a Peregrine falcon perched on the ledge of his kitchen window five years ago. Over the next couple of years, Arashiba enjoyed catching glimpses of the creature.

"It never startled me. I just always thought it was really cool," Arashiba said.

Last April, Arashiba was pleasantly surprised after a pair of Peregrine falcons made his balcony their home. He documented the experience, taking photos and videos sharing them on the social media application Instagram.

After Arashiba's apartment management received several noise complaints about the birds from neighbors, the pair was shooed away. But the falcons returned in June and laid eggs.

"When I saw they had laid some eggs, I thought, 'This is serious,'" Arashiba said.

"I reached out to the Field Museum and they gave me a lot of information about Peregrine falcons," Arashiba said. "I learned how they were federally protected and that these were the Belmont-Addison Peregrines. I also did my own research to learn more about them."

After the eggs failed to hatch, the pair left their post in late July.

The New York Times cites an increase of Peregrines in cities, describing the growth as a recent phenomenon. In the 1950s, the Peregrine population saw a rapid decline and were listed as an endangered species. Two decades later, the U.S. government banned the toxic pesticide DDT and, in conjunction with various Peregrine falcon release programs, saw a gradual resurgence of the Peregrine population.

The Field Museum's Chicago Peregrine Program estimates there are more than 20 pairs of Peregrine falcons in the city.

"Although historically Peregrine falcons are cliff-dwelling birds, we have seen them settling into cities," said Field Museum collections assistant Mary Hennen.

"For urban Peregrine falcons, the city serves as a pseudo-cliff," Hennen said. "It kind of makes sense because you have the lakefront which serves as a cliff, the tall buildings and balconies that serve as a ledge, little competition and ample prey."

"Wild birds go where they want. They make that decision," Hennen added.

The museum has set up a page of frequently asked questions about the birds, such as what they eat (other birds, including pigeons), how fast they fly (they can hit 200 mph when diving on their prey) and how much they weigh (1.25 to 2.75 pounds.) The females are larger than the males.

Arashiba has been reveling in the Peregrines' decision to choose his balcony. Like their last visit, he has continued documenting and posting photos and videos as the pair of falcons share food and communicate with one another.

Video

The male showed up with breakfast. A photo posted by @officebuddha on Apr 3, 2015 at 9:38am PDT

Arashiba remains fascinated by the urban Peregrines, as are his guests who stop by.

"When friends come over they are a bit nervous when they see the falcons. But they are delighted and excited," Arashiba said.

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