Iowa has nine species of bats, two of which are federally endangered species.
The Iowa Department of Natural Resources highlighted its frequent bat surveys and actions to protect their habitat during an international celebration, known as Bat Week, to spread awareness about bats.
While bats are often associated with the spooky season, Bat Week is all about promoting the year-round benefits, like pollination, insect control and seed dispersal, that the flying mammals provide to the ecosystem.
Bats are also known to eat crop pests, like corn rootworm and corn earworm. One study estimated that bats save corn farmers an estimated $1 billion annually because of their helpful eating habits.
DNR’s batty projects
In 2015, DNR partnered with Iowa State University to create a volunteer wildlife monitoring program to help track trends in bat populations in the state.
Iowa citizen scientists can sign up for the project and drive slowly along a predetermined route with a special microphone mounted to their car. The microphone picks up and records echolocation calls of bats and researchers can analyze these recordings to determine the species of bat.
The acoustic monitoring surveys have allowed DNR to gauge the distribution of bats in the state, and monitor the decline of certain species that are most hard-hit by white-nose syndrome, a fungal disease.
The data show the tri-colored bat and the myotis, or northern long-eared bat, populations have declined in eastern Iowa because of the deadly disease, which hits bats during hibernation.
Despite being the “most imperiled” species of bat in Iowa, the data show the myotis is present in all Iowa regions. The big brown species of bat, followed by the eastern red species, are most common throughout the state.
The Indiana bat is the other endangered species that calls Iowa home, though white-nose syndrome and loss of habitat have contributed to its population decline, according to ISU. Little brown bats, big brown bats, and tri-colored bats are also susceptible to white-nose syndrome. These bats tend to hibernate in cool, dark areas like caves or abandoned mines where the fungus thrives.
Iowa’s additional bat species include the silverhaired bat, evening bat and hoary bat.
In addition to monitoring bat populations, DNR has worked to restore bat habitat via private forest restoration, and the department incorporates bat-friendly practices to its forest stewardship plans.
According to DNR, bats thrive in forests that have a mostly open “mid-story,” trees with loose or clumpy bark, dead trees and lots of insects to eat.
Forest restoration includes removing invasive species like Japanese honeysuckle and European buckthorn which can crowd the mid story of a forest. Staff also use prescribed burning and certain forest thinning techniques to restore the habitat for bats. In all forest management plans, DNR includes a recommended percent of dead trees that should be left standing to provide habitat for bats.
From 2022 to 2024, DNR restored over 800 acres of both public and private forest using these methods and federal dollars earmarked for habitat restoration for endangered bat species.
What you can do to help bats
Similar management practices can be employed on private forest land, or on residential properties to help protect bat habitat.
DNR considers trees like shagbark hickory, shellbark hickory, white oak and American elm to be “bat friendly” trees since bats can make a home under the shaggy barks. Planting these trees or refraining from chopping them down can give the nocturnal critters a safe place to rest during the day.
Property owners can also work to remove invasive species that clog up the bat-friendly forest, and leave some dead trees standing when it’s safe to do so.
Iowans can also stay out of mines and caves during the winter months, when bats might be using them for hibernation.
Finally, adding a bat box to a property gives bats a home, and might keep them from trying to roost in an attic. Big brown bats are most likely to try to roost in human structures, according to DNR. Iowa State University has several resources for safely removing bats from a home and on building a bat box.
