Historic Iowa tower home to family of chimney swifts
Birds being studied in Althea Sherman's 101-year-old laboratory
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BUCHANAN — History and nature collide in a quiet, remote field in the tiny, unincorporated Cedar County community of Buchanan.
Located about five miles west of Tipton, the Bickett-Rate Preserve is where citizen scientists are once again studying chimney swifts — slender birds with long, curved wings — in a unique tower built 101 years ago by pioneering ornithologist Althea Sherman.
“It is living history. It’s still being used for its original purpose. It’s alive and working today,” said Mike Boyle, treasurer of the Cedar County Historical Society, which has partnered with the Johnson County Songbird Project to rescue, restore and erect Sherman’s long-neglected tower laboratory.
Sherman, a self-taught bird expert whose chimney swift studies earned her national acclaim, built the tower in 1915 in the Clayton County town of National. It fell into disuse and deterioration after her death in 1943.
Now, for the third year in a row, swifts occupy the tower, raising four chicks under the watchful eyes of Barbara Boyle of Williamsburg, who was instrumental in the 21-year effort to save and restore the tower, and of Cedar Rapids naturalists and photographers Linda and Robert Scarth.
The Scarths, who visit the tower three days a week during nesting season, have documented each tower brood since the first in 2014. They observe and photograph the swifts through the same windows and peepholes, accessible from a circular stairway around the chimney, used by Sherman to make her groundbreaking observations, which she illustrated with meticulous drawings.
“We are getting to observe what Althea saw,” Linda Scarth said.
Meanwhile, Barbara Boyle monitors a video feed and records her observations in a journal — now exceeding 40 pages for this season alone — that conveys both domestic tenderness and drama.
The drama ensued June 8 with the disappearance of one of the mated adults, leaving the female to attend three eggs in the nest. By June 17 she had attracted a new mate, which promptly cleared the nest of the old eggs, presumably in the interest of perpetuating his own genetics.
“As far as we have been able to determine, such behavior had not been previously documented in chimney swifts,” Barbara Boyle said
By July 4, the newly mated pair had filled the nest with five new eggs, four of which have since hatched and become gaping mouths for their parents to feed.
Barbara Boyle said she is astounded by the effort required of the parents to feed their chicks and by the chicks’ rapid growth.
The regular observers marvel at the swifts’ nest, affixed to the wall of the artificial chimney with the birds’ own glue-like saliva.
With its strategically placed braces, it looks like an engineer helped design it, Mike Boyle said.
The chicks help keep it clean by somehow knowing to defecate over its side, Barbara Boyle added.
Chimney swifts are adapted to nest in chimneys and on other vertical surfaces such as wells, hollow trees and caves. They spend much of their lives airborne and cannot perch, clinging instead to vertical walls with their sharp toes, their stiff tails helping to support their weight.
When entering the chimney, the swifts “drop in backward, fluttering their wings to control their descent,” Linda Scarth said.
On Wednesday, exactly a year after the unexpected death of raptor expert Bob Anderson of Decorah, the Scarths and the Boyles, who are not related, reminisced in the shade of the tower about Anderson’s kinship with Sherman and his support for their efforts to put nest cameras in the tower.
Anderson, who led the successful effort to restore peregrine falcons to their native Mississippi River bluff eyries and founded the world-famous Decorah eagles nest cam, donated all the video and recording equipment and helped install it.
Anderson, who studied Sherman’s writings and admired her innovative research techniques, “so wanted us to live stream video from the tower. He believed in this project so much,” Barbara Boyle said.
But drama at the Sherman tower has not been limited to the swift nest. Project leaders’ efforts to live stream video from the cameras installed by Anderson have been thwarted by insufficient band width of their internet provider, they said.
In lieu of live streaming, which will have to wait until more band width becomes available, Mike Boyle regularly emails recorded video to Barbara Boyle, who reviews the video and posts updates to more than 200 email recipients. Anyone who wants to subscribe to the updates can reach her at firstname.lastname@example.org
The Scarths post their exquisite photos and insightful commentary on their blog, http://scarthphoto.com/wp/