LINCOLN PARK — Scientists at Lincoln Park Zoo are recreating a 113-year-old study of birds in Lincoln Park, which they found by matter of chance inside an old book.
The little book, measuring just 6 inches tall by 4 inches wide and about as thin as a pencil was hidden away in an antique store, before zoo biologist Allison Sacerdote-Velat found it.
"It's a tiny little book, but the information in it is so vast," said Mason Fidino, the zoo's Wildlife Management Coordinator.
That information includes a study conducted in Lincoln Park in 1898 that recorded every bird seen in the park during the spring migratory season and continued each year through 1903.
Herbert Eugene Walter and his wife Alice Hall Walter made their way around the massive park almost daily and used a set of opera glasses for faraway birds, according to Fidino.
"We don't know much about exactly how they walked the park, but we are trying to replicate it as closely as possible," he said.
For Fidino, that meant walking 11 miles a day during a pilot study last year, and about 6½ miles a day while on the lookout this year — he has an intern that completes the other half of the route.
"It's a lot of walking," he said.
That pilot study lasted two weeks last year, and in those two weeks Fidino lost 10 pounds.
"I was ready for the summer," he said. "It was a little hard on me to begin with. Now it's just walking six miles."
The Walters, the authors of "Wild Birds in City Parks," averaged about 75 daily walks from March to May each year, which equates to five days a week with a few extra days thrown in.
During the peak migratory season from May 7-20, when many birds plop down in the zoo's Nature Boardwalk area for a dip, Fidino plans on making the walk seven days a week.
Now that the sun is coming up early, he usually starts that walk at 6:30 a.m., when the birds are chirping.
"Every bird has its own audio calling card," Fidino said.
Sparrows sing a jazzy song. It gives three bops at the beginning and lets it rip, according to Fidino.
The Northern cardinal's tune is like a laser gun.
"... sort of a 'Pyew, pyew,' It pays to have fun with the songs," Fidino said.
Researchers with the zoo's Urban Wildlife Institute spent about 50 hours going over songs and bird calls before heading out for the study.
A hundred years ago, the Walters had to train their ears to differentiate between bird calls.
"Now we have apps for that," Fidino said.
As the city has changed over the past century, so has the make-up of its birds, according to the preliminary results of the study.
During the time of the first study, Blue Jays were among the top three most common birds in the park along with the Common Grackle and the American Robin.
The Grackle and Robin remain common, but the Blue Jays have become a rarity in Lincoln Park.
Habitat loss has contributed to the disappearance of a handful of species such as Henslow's sparrow, which build their nests on the ground. They left for less-populated areas.
"This is like the perfect treat. It's like a treasure for us to find something like this and look at the similarities," Fidino said.