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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.

Introduction

Plants and animals can tell us much about the quality of a landscape. Breeding birds are particularly informative because most species are habitat selective. They are mobile enough to find favorable breeding sites, and they are relatively easy to observe. Like other organisms, wild birds cope with the cumulative effects of habitat degradation, environmental pollution, invasive species, climate change, and other (often un-measurable) threats to environmental quality. The regular presence of certain bird species, therefore, helps us assess the overall ecological health of an area.

The Laurentian mixed forests of North America’s western Great Lakes region support well over 100 species of breeding birds depending on the size and heterogeneity of the landscape. Some of these bird species are very sensitive to forest condition, while others are more tolerant of disturbance and might even prefer degraded habitats. Of course, forest birds provide valuable ecological services in their own right but, because they are relatively conspicuous and well-known, forest birds are especially useful as cost-effective and reliable indicators of a healthy forest environment.    

The purpose of this web site is to provide a rigorous, transparent tool for measuring forest health in northern mesic forests of the western Great Lakes region based on local breeding bird assemblages.  

Our general approach is applicable anywhere and for any group of species or environmental variables, but our specific calculator is appropriate for northern mesic forest landscapes of northern Minnesota, the Upper Peninsula of Michigan, northern Wisconsin, and possibly other areas of the northern Great Lakes region (Bird Conservation Region 12). In fact, this tool has already been successfully applied to a forested landscape in northern Wisconsin managed under a working forest conservation easement called the Wild Rivers Legacy Forest (Gnass 2012; click here to learn more). It can be used to guide sustainable forest management and conservation practices and monitor long-term outcomes.

Read more about Indices of Forest Health»