January-February 2023 • Nebraskaland 41
compiling and analyzing data. Although bats remain active
in autumn, researchers don't want to interrupt mating,
hibernation and migration preparations that occur in the fall.
Fill said initial results for 2022 indicate even fewer northern
long-eared bat identifi cations.
More analysis is required before conclusions can be drawn.
Analysis may additionally be hampered from an inability
to sample a majority of sites in 2019 and 2020 because of
historic fl ooding and the COVID-19 pandemic.
"The program standardizes the data collection process
so that it's uniform and comparable," Fill said. "This allows
researchers from across the country to get a better idea of bat
distributions, trends and declines along with a better sense
of how bats are doing. It's not perfect, but bats are so diffi cult
to study, it's hard to come up with anything that would be."
Fill supplements data collected via stationary detectors
with mobile driving surveys using a detector attached to the
top of a car, as well as occasional capture surveys.
"After sunset, we'll drive a route between our sampling
points, often along gravel and dirt back roads, to collect bat
calls," he said. "With this particular detector, we can see and
hear the bats when they fl y over the car."
In a previous project in 2018 and 2019, Fill set up arrays
of acoustic detectors in farm fi elds, prairies and wooded
areas near Homestead National Monument outside Beatrice,
Nebraska. In addition to tracking northern long-eared bats
and white-nose syndrome, he developed "heat maps" that
showed bats' foraging patterns in diff erent landscapes. He
found bats are most active along the edges of fi elds and near
wooded areas and streams, which may encourage farmers
to retain those landscape features to maximize the insect-
reduction benefi t they receive from bats.
N
Leslie Reed is the director of public affairs at the University of
Nebraska-Lincoln's Communication and Marketing Department.
This is her first appearance in Nebraskaland Magazine.
Fill holds an evening bat
(Nycticeius humeralis).
PHOTO COURTESY OF CHRIS FILL
