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Peregrine Falcon Nest Cam

Peregrine Falcon Camera

Peregrine Falcon Life History

Despite their relatively small appearance (36-49 cm [14"-19"] tall), Peregrine Falcons (Falco peregrinus) are the fastest bird (and animal) on Earth and can reach speeds as fast as 383 kph (238 mph). These incredibly fast speeds help Peregrines primarily prey on birds, especially songbirds, ducks, gulls, pigeons, and shorebirds, though they do consume bats on occasion. They are globally widespread and reported on all continents except Antarctica. Despite massive population declines in the 1950s-1970s caused by DDT effects, Peregrine Falcon populations are considered globally stable now that this toxic pesticide has been banned. However, here in Wisconsin, since October 1975 they are still listed as "state endangered."

Ages of Peregrine Falcons: Nestlings (left), juvenile (middle), and adult (right)

Baby falcons
Perched falcon
Perched falcon

Peregrine Falcons nest naturally on the edges of high cliffs, though they have adapted well to humans by using nest sites located on tall buildings, quarries, bridges, transmission towers, and in artificial nest boxes. According to the WI Breeding Bird Atlas II Project (2015-2019), Peregrine Falcons have nested in Wisconsin primarily along the Mississippi River and Lake Michigan but also in urban areas including Green Bay, Milwaukee, Madison, and the Fox Cities. Some pairs mate for life, particularly those in more remote and natural landscapes, but not all pairs do. We are thrilled UW-Green Bay's David A. Cofrin Library has active nesting Peregrine Falcons, which you can learn more about in the sections below.

UW-Green Bay Peregrine Falcon Nest History

Two Peregrine FalconsPeregrine Falcons have been detected on the UW-Green Bay campus since 2011 (in recorded history) and have been successfully nesting almost annually on the UW-Green Bay David A. Cofrin Library since 2017. They utilize a nest box that was installed inside an air shaft on the library that has a layer of small pieces of gravel where the birds scrape in an indentation for laying their eggs.

Once a falcon pair is mated, the female will lay between 2 and 5 eggs in early April, and both parents will incubate the eggs for about a month. When the eggs hatch, the altricial young (i.e., helpless young completely dependent on their parents) stay in the nest for 35-42 days after which they grow in flight feathers and practice flight. They will stay with their parents for a time to learn how to fly and hunt and eventually fledge (i.e., leave the nest) shortly thereafter.

Over the years, UW-Green Bay faculty, staff, and students and the general public have fallen in love with the Peregrine Falcons that nest here on Two Falcon Chickscampus and closely follow their nesting phenology. Installing a camera with a YouTube live stream has made these magnificent birds that much more popular and viewable to all. These birds can be seen perched on the David A. Cofrin Library throughout the year or heard as they make their well known alarm calls ("kak kak kak"). Bird observers can also view them rapidly soaring overhead or actively hunting around campus in search of their next prey item.

Mimi and Rupert have been the primary nesting pair of Peregrine Falcons here on campus over the years. Mimi and Rupert were originally banded in 2014 and are approximately 8 years old. Mim was born in Milwaukee County, while Rupert was born in Oshkosh. However in 2021, Mimi successfully nested with one of her offspring, Leopold.

Here is a complete summary of the UW-Green Bay's Peregrine Falcon nesting pairs and their young:

YearAdultsBanded Fledged Young
2011unknown0 young: nest failed
2012unknown0 young: nest failed
2016Mimi & unknown male0 young: nest failed
2017Mimi & Rupert4 young: Austin (male), David (male), Douglass (male; died in late summer 2017), and Peter (male)
2018Mimi & Rupert3 young: Annie (female), Gary (male), and Tom (male)
2019Mimi & Rupert4 young: Leopold (male), Muir (male), Carson (female), and Thoreau (male)
2020Mimi & Rupert4 young: Joanne (female), Cathie (female), Arvid (male), and Robert (male); though none were banded due to the Covid-19 pandemic
2021Mimi & Leopold2 young: Holly (female) and Wolf (female)

To learn more about the Peregrine Falcons that have nested on campus, please download annual reports produced by Greg Septon on "Wisconsin Falconwatch."

Banding UW-Green Bay's Peregrine Falcon Chicks

Master raptor bander Greg Septon, the founder of Wisconsin Peregrine Master raptor bander Greg SeptonFalcon Recovery Project, annually comes to UW-Green Bay to band Peregrine Falcon chicks. He conducts a series of measurements on each bird, determines a bird's gender, and attaches metal and color bands to each bird to assist with resighting a bird in the field at a later time. Students from UW-Green Bay's Green Bay Audubon student organization typically assist Septon during the banding process along with other interested campus staff, faculty, and visitors. You can view Mimi's and Rupert's offspring, Annie, Gary, and Tom, after they were banded in 2018 in the YouTube video below.


In collaboration with UW-Green Bay's Facilities Management (Paul Pinkston) and UW-Green Bay Police, Cofrin Center for Biodiversity faculty and staff (Dr. Amy Wolf and Dr. Robert Howe) and UW-Green Bay's Green Bay Audubon student club manage the campus' Peregrine Falcon nest box. We thank the UW-Green Bay Chancellor and leadership team (especially Holly Keener and her "Daily Phalconeer" reports) and David A. Cofrin Library staff for ongoing support, Paul and Annie Mueller who helped fund the nest camera, UW-Green Bay's Division of Information Technology (Ron Kottnitz and Monika Pynaker) for enabling the live stream camera, and Tom Erdman's leadership for documenting and monitoring the earliest nesting pairs of Peregrine Falcons on campus. The Cofrin Center for Biodiversity and Facilities Management paid for the nest box. We are especially grateful for UW-Green Bay students Jacob Woulf (student lead), Brandon Byrne, and Noah Nei for their work in installing the nest box and camera, monitoring the phenology of the campus nesting Peregrine Falcons, and archiving thousands of hours of nest camera footage. Lastly, we thank master raptor bander Greg Septon for banding our campus Peregrine Falcon fledglings year after year.


Peregrine Falcon life history accounts came from and Audubon. Wisconsin reports of Peregrines came from eBird reports.