Peregrine project finds success at GRE

by Joni Astrup

Associate Editor

Eight years ago, Brenda Geisler got her first glimpse of a bird species that would come to play an important role in her life.

Nicolas, Rebekah, Caleb, and, in front Grace Lanham were able to touch a young peregrine on the day it was banded at Great River Energy. Brenda Geisler is holding the bird.
Nicolas, Rebekah, Caleb, and, in front Grace Lanham were able to touch a young peregrine on the day it was banded at Great River Energy. Brenda Geisler is holding the bird.

The bird was a peregrine falcon. Geisler had never seen one before 2006, when the first one appeared at Great River Energy in Elk River, checking out a new nest box that had been installed 110 feet above the ground at the Elk River Energy Recovery Station at 17845 Highway 10.

Geisler, who works as an administrative assistant at GRE, was the driving force behind that nest box, which has grown into a successful peregrine project that she continues to manage today.

Considered the world’s fastest creature, peregrines have nested at GRE for each of the last eight years. A total of 24 young have fledged from the nest box located there.

Amy Ries with the Raptor Resource Project in Decorah, Iowa, described the GRE box as “extremely productive.” The Raptor Resource Project bands the young at GRE annually.

“We get young there every year,” Ries said. “The falcons are healthy and they’ve always fledged well out of that box.”

Ries said the history of peregrines and power plants dates to 1990, when the first peregrine nesting box was installed at a Northern States Power plant. It proved successful, and other power plants like GRE followed suit. Ries said those boxes have played a key role in the recovery of the peregrine population, which at one point is believed to have dwindled to just 19 pairs in the United States due to the pesticide DDT. The use of DDT is now severely restricted.

Sawatzke, an adult male peregrine, captured May 28 on GRE's birdcam in Elk River.
Sawatzke, an adult male peregrine, captured May 28 on GRE’s birdcam in Elk River.

Ries said it has been amazing to see the birds make a comeback. The peregrine falcon was removed from the U.S. endangered species list in 1999.

“I don’t believe we would have gotten there nearly as fast as we did without the help of power companies,” Ries said. “They were absolutely crucial to the species recovering as well and as quickly as it did. Literally thousands of peregrines have fledged (from power plants) across the Midwest and then they’ve gone on and established their own nests elsewhere.”

Geisler had approached GRE’s plant manager, Wayne Hanson, about putting up a peregrine nest box after reading the article by peregrine expert Bob Anderson called “Attracting and Managing the Peregrine Falcon at Electricity Generating Facilities.”

Hanson gave Geisler the go-ahead and suggested she find a Boy Scout to build the nest box. Geisler located Daniel Sundberg of Troop 90. He built the box for his Eagle Scout project.

She then worked with Anderson, director of the Raptor Resource Project, to determine the correct location for the box.

The nest box was mounted on the Elk River Energy Recovery Station in February 2006. The first year, a male falcon showed up.

No birds nested there that year, but in 2007 the first pair claimed the nest box and produced young, called eyasses.

Mary Ellen incubated eggs in the GRE nest box on May 12.
Mary Ellen incubated eggs in the GRE nest box on May 12.

Initially, a lone video camera recorded the activity in the nest box and streamed it to GRE’s website at

Two more cameras were added in 2008 and a microphone was placed there in 2010 when a new nest box was installed. The second nest box was constructed by Elliot Cornelius as a 4-H project. The “birdcam” continues to be active on GRE’s website.

Ries said peregrines are interesting to watch.

“They have a lot of charisma. They’re amazing fliers and they have such presence,” she said.

Geisler said it has been an honor and privilege to observe and work with the peregrines.

“I’ve learned so much, but every year I learn something new,” she said.

One of the things that surprised her most came after the microphone was placed at the nest box. Geisler discovered that as the eggs are hatching, the female peregrine makes sounds to coax her young out of the egg, and the eyas answers from inside the egg.

Geisler said she’s been struck by the bird’s strong maternal instinct.

“They’re magnificent creatures and the tenderness they display in that nest box is amazing,” she said.


Amy Ries (left) with the Raptor Resource Center attached a band to an eyas while Brenda Geisler, administrative assistant, Elk River Resource Recovery Project (right), kept it calm. Three young peregrines were banded June 6. Photos courtesy of Great River Energy
Amy Ries (left) with the Raptor Resource Center attached a band to an eyas while Brenda Geisler, administrative assistant, Elk River Resource Recovery Project (right), kept it calm. Three young peregrines were banded June 6. Photos courtesy of Great River Energy

Mary Ellen, the peregrine female who has nested at GRE in 2013 and 2014, still had juvenile feathers when she showed up last year, Geisler said. Because she was banded, Geisler was able to determine that Mary Ellen hatched in 2012 at Great River Bluffs State Park in Minnesota. Last year was her first year on the nest, where she laid three eggs and meticulously cared for the young after they hatched.

For the last several years, Geisler has been sharing the nest box project and her knowledge of peregrines with school children. She visits classrooms and does presentations, usually in March or April when the peregrines are just returning to the nest box. The students then follow the nesting progress on the birdcam.

One of the schools she has visited is Epiphany Catholic School in Coon Rapids. This year, 56 Epiphany students attended the banding.

Students also often play a key role in naming the young birds. This year the Epiphany students held a naming contest for the birds and the winners were Andee (female) and Bullet (female).

In addition to managing the nesting box, Geisler assists the people from the Raptor Resource Project when they come to GRE each summer to band the birds.

The peregrines are typically banded in June when they are 18 to 22 days old. By 40 days, they are grown and begin leaving the nest. After that, Geisler said they will remain in the area until they migrate in September or October.

Once the aluminum identification bands are attached to their legs, the birds’ band numbers are entered into the Midwest Peregrine Falcon Database so they can be tracked in the future. Geisler has had follow-up reports on two of the 24 young that have fledged from GRE.

One, Patricia, hatched at GRE in 2013 and was captured by a Wisconsin falconer on Sept. 21, 2013, as the bird migrated south for the winter. She was captured near Genoa, Wisconsin —165 miles south of her nest site in Elk River. She was reported to be in good condition and was immediately released, Geisler said.

A second bird, Larissa, hatched at GRE in 2012 and was sighted by Anderson on May 14, 2013, at Wyalusing State Park in Wisconsin. Anderson also identified a male, Joe, a 2010 hatch from a generating station in Wisconsin. The pair did not produce any young and vanished about midway through the nesting season, according to a Raptor Resource Project report.

Not every peregrine is a success story, of course.

Geisler said they lost one eyas, Bella, in 2009. It was determined she died from frounce, a yeast infection of the digestive tract caused by a protozoan that can be present in pigeons. The other three nestlings were also showing signs of the disease, so Geisler and Anderson went up to the nest box and treated the three with an antibiotic. That required putting a pill down the throat of each of the eyasses.

“That wasn’t easy, either,” Geisler said.

Geisler said this year they also unfortunately lost an eyas that fell from the nest box as Mary Ellen accidentally clipped it with her wing when she suddenly left the nest box.

Geisler has a front-row seat to the peregrine activity every year, as live views from the three cameras run continuously on a monitor on her desk at the power plant. She has a three-ring binder for each year of nesting activity, full of photos and meticulous records.

Ries, of the Raptor Resource Project, described Geisler as “awesome.”

“She knows every detail of that program,” Ries said.

Geisler said the peregrines are part of her life for six months every year.

“It’s something to look forward to and I miss them when they’re gone,” she said.

Fast Facts about Peregrine Falcons

•Baby falcons are called eyasses. They are covered by white down when they hatch, which is replaced by feathers in three to five weeks.

•One parent (often the female but sometimes the male) stays with the chicks while the other finds food for the brood.

•Eyasses eat an incredible amount of food — but then, they double their weight in only six days and at three weeks will be 10 times birth size.

•Peregrine falcons are about the size and weight of a crow. Females are larger and more powerful than males.

•Peregrine falcons are nature’s fastest fliers. They have been clocked diving at speeds of up to 220 miles per hour.

•Peregrine falcons feed primarily on birds they take in the air; their prey includes ducks, pheasants and pigeons.

•In the 1960s, scientists discovered that DDT was interfering in the eggshell formation of meat- and fish-eating birds. Healthy birds were laying eggs so thin they were crushed by the weight of the incubating adult. By 1968, the peregrine population was completely eradicated east of the Mississippi River. In 1972, use of DDT was severely restricted in the United States and worldwide.

•Peregrine falcons are considered a threatened species, having been upgraded from the endangered list.

•Power plants are uniquely suited to hosting peregrine nests. The height of facilities, the generally open area where plants are sited and proximity to rivers provide beneficial places to host nesting boxes.

Source: Raptor Resource Project, 

Great River Energy