Long-term efforts to study Indiana bat maternity colonies

The Indiana bat (Myotis sodalis) is a federally endangered species that was first discovered roosting in Wyandotte Cave in southern Indiana in the early 1900s. Due to declining populations in caves, the species was one of the first to be listed as endangered when the Endangered Species Act was written in the late 1960s. Since the late 1990s, the Center for Bat Research, Outreach, and Conservation at Indiana State University (ISU) has monitored the status of a population of the Indiana bat near the Indianapolis International Airport in central Indiana. In compliance with the Endangered Species Act, the Indianapolis Airport Authority and US Fish and Wildlife Service implemented a series of proactive conservation measures during two major periods of airport expansion. Early conservation efforts included habitat protection and regular capture surveys in the vicinity of the Airport; when Indiana bats were captured, biologists glued tiny radio transmitters to their backs to track the bats to roost trees and while they are out foraging at night. Both activities gave us critical information on the whereabouts of the bats, population size and sex/age ratios, and a better understanding of the bat’s biology and ecology. The Airport Authority also set aside almost 400 acres of land to provide a permanent home for the Indiana bat colony that was discovered in the mid-1990s, planted thousands of trees, funded outreach efforts by the Bat Center at ISU, and funded annual monitoring surveys. Some of the protected land is now a county park—Sodalis Nature Park—named after the Indiana bat.

4 HorsemenThe Indiana bat maternity colony, which includes adult females and their pups plus the occasional adult male, has hovered around 150 bats since 1997. At least seven other bat species reside in the same protected areas, including the federally threatened northern long-eared bat (Myotis septentrionalis). By placing unique forearm bands on bats captured during summer and then coordinating with biologists who survey wintering sites, we’ve learned that Indiana bats make annual migrations to the Airport site from caves 50-100 miles away in southern Indiana. Adult females begin the summer season roosting in sheltered sites within the forest, but move as a large group to tall roosts with lots of solar exposure once pups are born in early June; these warm roosts help females and their pups to conserve energy. By July, juvenile bats have begun to fly and the colony starts to break up into smaller groups, with some individuals choosing to roost in sheltered trees in small woodlots again. Throughout the summer, Indiana bats often forage along a 1.5 mile section of stream corridor that runs through their main roosting area, but some individuals make long forays across neighborhoods and busy highways to forage over ponds and other creeks. A few stragglers roost in small groups across the study site until late September/early October; then the bats move to their hibernation sites in southern Indiana.

It’s really nice to know that endangered Indiana bats can co-exist with development when natural areas are also conserved. This long-term conservation success story demonstrates the effectiveness of the Endangered Species Act and proactive conservation efforts!

Joy O’Keefe is an Assistant Professor and Department of Biology Director for the Center for Bat Research, Outreach, and Conservation at Indiana State University
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Showing 13 comments
  • Lee Grove
    Reply

    Thank you so much for this information Professor O’Keefe! The more we learn about bats and their habits and habitats, the more fascinating it becomes. They are such beneficial creatures and this helps a lot to educate those that may not understand the importance of the roles they play in our world.
    Thank you for all you do.

  • Al
    Reply

    Sorry this is a bit off-topic but I didn’t know where else to ask this question. We’ve had a couple of bat houses for years with no problems until last year, when we started finding more and more dead bats. It appeared at least most if not all of last years pups perished, one by one, from some mystery disease. The two houses were incredibly full and dozens left the bat houses and began nesting on our personal home. It seemed already too late, though, as even those pups perished. We saw no signs of white on their noses or faces, nor on the adults.

    I’m just wondering if anyone else had this problem last year?

    This winter we pitched the two older bat houses and purchased one new very large one, which we’ll put up before Spring. We’ll be placing it further from our house this time, as well.

    • Organization for Bat Conservation
      Reply

      No need to apologize Al — What state do you live in? We’re based here in Michigan and we have received some phone calls that mirror what you’ve been saying.

      Phil Garofalo
      Digital Media Manager
      Organization for Bat Conservation

      • Al
        Reply

        Hi Phil, Sorry it’s taken me so long to respond to your question. Despite looking, I couldn’t find this article again until now to see if anyone had answered me.

        In answer to your question, we live in sw Missouri.

  • Vern Ellis
    Reply

    keep up the good work.

  • Barbara Kennedy
    Reply

    I just got a bat house in January and planning to put it somewhere on my property. My house faces east so really the only place I can think to put the house is on the south side of the house where it would have sun. I live in Kentucky and would welcome any additional information you might have. I am very new to this.

    • Organization for Bat Conservation
      Reply

      We have an eGuide with all kinds of tips and tricks that we offer as a free service. Feel free to download away and message us if you have any further questions.

      https://batconservation.org/help/bat-houses/

  • Ronda M.
    Reply

    Wonderful article! Thank you for posting it. I’m happy to see the efforts that have been taken to preserve this bat colony.

  • Patricia Doty
    Reply

    We live in the BVI and have a bat house in the correct position, but no takers. What else do we need to do?

  • Todd Stewart
    Reply

    We need your help curbing excessive logging on state owned property. I have been told that they are not doing correct assessments for colonies before logging.

  • Todd Stewart
    Reply

    What about the effect excessive logging by DNR is having on bat habitat. Over 1000% increase with only 5% protected.

    • Organization for Bat Conservation
      Reply

      Todd,

      This is something we’re also worried about. While White-nose Syndrome is getting the brunt of news coverage, that main threat to bats, worldwide, remains habitat loss and habitat destruction. We’re hoping to see stronger laws implemented across the nation in coming years.

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