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Cofrin Center for Biodiversity

An Ecological Index of Forest Health Based on Breeding Birds

By: Erin E. Gnass Giese, Dr. Robert Howe, Dr. Amy Wolf, Nicholas Miller, and Nicholas Walton

Click to go to introduction. Link to introduction. Click to learn more about Indicies of forest health. Link to IEC Explained. Click to download the calculator. Link to the IEC calculator. Click to go to IEC instructions. Link to calculator instructions.

Share Your Calculated IEC Score with Us

If you would like to share your IEC scores with us or provide feedback on what your calculated scores indicate for your area, please feel free to contact us (see below).  We look forward to hearing from our users and are eager to receive any and all feedback on the use of the IEC calculator.

To share your IEC scores or for more information or for questions on how to use the IEC calculator please contact Erin Giese, Biodiversity Research Specialist and Data Manager, Cofrin Center for Biodiversity, UW-Green Bay at



Development of the forest IEC calculator was a collaboration involving the University of Wisconsin-Green Bay, The Nature Conservancy (TNC), timber investment management organizations, and many other organizations including the US Forest Service (USFS), WI Department of Natural Resources (WDNR), Marshfield Clinic, University of Wisconsin-Madison, and the Natural Resources Research Institute of the University of Minnesota-Duluth. 

Funding was provided by TNC and the Cofrin Center for Biodiversity (CCB), and administrative support and webpage development were provided by the UW-Green Bay and CCB.  The USFS, WDNR, Marshfield Clinic, UW-Madison, and volunteer birders generously allowed us to use their data collected for other projects for developing our IEC model. 

We also appreciate the support and field research assistance from many TNC staff members and volunteers, UW-Green Bay faculty and staff members, participants in the annual Nicolet National Forest Bird Survey, and hundreds of other dedicated and hardworking observers and researchers (including volunteers).  Participants at the November 2013 (Rhinelander, WI) workshop entitled "Development of a regional forest assessment tool for the western Great Lakes region" also provided extremely valuable feedback on the usage of this tool, which has been incorporated into our spreadsheet and current research.

Finally, we offer a special thanks to Stephanie Beilke who provided a photograph of an Ovenbird (response function), Robert Howe who provided a photograph of Memorial Grove Hemlocks State Natural Area (header image), Robert Kleppin who provided a photograph of Flambeau Flowage (header image), Michael McDowell who provided a photograph of a Blackburnian Warbler (header image), Gail Van Sluys who provided a photograph of the Wild Rivers Legacy Forest (header image), and Scott Giese who provided all of the remaining photographs included on this webpage

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