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Natural Heritage biotic inventories

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The Natural Heritage Inventory Program (NHI) uses a standard methodology to conduct biotic inventories, or field surveys, for rare species and natural communities throughout Wisconsin. Our general approach involves the following:

  • collecting relevant background information;
  • planning and conducting surveys;
  • compiling and analyzing data; and
  • mapping rare species and high-quality natural community and geological feature locations into the NHI database.

Inventory efforts are often conducted as part of the DNR's property planning process. Results are analyzed to identify ecologically significant sites, called primary sites, and data are synthesized and interpreted and findings are provided for planning purposes via NHI inventory reports.

Inventory at the Flambeau River State Forest

Primary sites

Primary sites offer major protection and/or restoration opportunities and are used, along with other sources of information, to help guide the department's master planning efforts. Each site contains documented, significant occurrences of rare and/or representative high-quality natural features. Department master planning teams, land managers and the general public can reference these sites during master planning efforts. Primary sites can also be considered "High Conservation Value Forests" for the purpose of forest certification.

Primary sites are delineated on maps using inventory results and other data, and generally encompass a property's best examples of one or more of the following:

  • rare natural communities and high-quality examples of representative natural communities;
  • documented occurrences of rare species populations and/or rare species habitat; and
  • opportunities for ecological restoration or connections.

Some primary sites are already State Natural Areas, while others do not have any special designation when the biotic inventory is conducted. Due to the ecological importance of these sites, they often receive special consideration during the development of master plans. Management is either deferred for a period of time or is done following consultation with an interdisciplinary team. The deferral or consultation process continues until the master plan is finalized in order to preserve the best possible range of opportunities for master planning teams to consider.

Inventory reports

Natural Heritage Inventory reports synthesize and highlight the best opportunities to conserve ecological diversity at a specific site. These reports include a variety of background information and the primary sites identified for the property or study area. Find an NHI inventory report.