Eve Cusack may be on summer break from her teaching position at Bloomington Montessori School, but she’s busier than ever — capturing, collecting information and sharing data about migratory birds that fly through a 90-acre farm east of Bloomington on Kent Road.
The summertime program that Cusack helps oversee is part of the Monitoring Avian Productivity and Survivorship program through the Institute for Bird Populations. The MAPS program has more than 1,200 stations across the United States and Canada, all collecting data to help answer questions about birds, from declines in population to why there are differences between regions and habitats.
Support for the local program comes from Indiana University’s Grand Challenges Initiative, Prepared for Environmental Change. One discovery made with the MAPS data was that West Nile virus is killing more birds than previously thought.
From June through August, Cusack and other volunteers, including her husband, Sam, will be setting up 13 nets to capture birds flying through the woods and open meadows near Lake Monroe. The project is done during migration season so volunteers can learn more about the birds’ habits and well-being.
The nylon nets are set up between 10-foot aluminum poles only when people are there to monitor them and ensure the birds that are caught do not linger long before they are released. Great care is taken to ensure the birds are treated with the utmost care and respect. The nets are checked at 40-minute intervals from before dawn to just after noon.
“It starts Memorial Day weekend and ends the week before school,” Cusack said. During the 10 weeks, many species of birds are caught in the nets.
“We catch a lot of ruby-throated hummingbirds,” Cusack said. She carries sugar water in a pocket to use to revive any of the hummingbirds who need it.
The nets also catch a lot of warblers — common, yellow-throated, Kentucky, American red start and prairie — as well as white-eyed vireos, indigo buntings and northern cardinals. Last summer, 37 bird species were caught in the nets; the year before, 29 species were caught. The largest of last year’s birds was a blue jay that weighed 84 grams (0.19 pounds). A pileated woodpecker was caught in the net, but it broke out before the volunteers could band it.
Sometimes the birds bite. Cardinals and the rare titmice are two species known to draw blood.
“Chickadees will bite a lot, but it doesn’t hurt,” Cusack explained. “Warblers just lay there.”
On the first day of netting last year, Cusack said, 36 bird species were caught. “We had 50 birds at one time,” she said, adding that it was a “puzzle” as to why there were so many birds that day. Was it the mild weather, the fact that there were no flooded areas nearby or that it was just a year of plentiful food for the birds?
While Cusack and her husband, Sam, have been working with MAPS projects since they lived in Louisiana, many of the local volunteers are students or bird lovers who just want to help.
“Anyone can volunteer who wants to,” Cusack said. This past year, more than 300 people helped.
Cusack said taking birds out of the nets is the most difficult task, since it takes delicate and quick hands to untangle feet and wings, releasing the bird into a hand-hold that usually keeps the bird safe and secure. Cusack usually wears cargo pants with pockets stuffed with the cotton bags with draw-string closures used to keep birds calm in a dark environment while they wait to be assessed and released.
“Some birds I’ll catch three or four times a season,” Cusack said.
Once a bird has been bagged, Cusack said they are banded, assessed and released in the order in which they were caught. That ensures each of the birds is captive for about the same length of time.
Besides other volunteers, Cusack said there are sometimes guests who come to watch. They can learn a lot by watching the volunteers assess the birds, she explained. An example is looking at the birds’ feathers, which can often reveal how old the bird is — first-year birds usually have slightly different feathers and characteristics than older birds.
Each bird that is caught is banded, so if it’s ever caught again, it can be identified and the location where it was banded can be known. The birds are also checked to determine sex and age.
The local MAPS station was begun in 2016 when Cusack and Ellen Ketterson, director of IU’s Environmental Resilience Institute, partnered to bring more bird-related programs to the Kent Farm property. The third season of banding has just begun — and the volunteers are spending their mornings checking the nets, eager to add more birds to the data.