Habitat Modeling & Products


What is Habitat Suitability Modeling?

Habitat suitability modeling (HSM) is a statistical method for predicting the suitability of habitat for a given species. The model identifies the environmental factors that a species selects for, or avoids, based on the availability of those factors across a landscape and outputs an index of suitability based on these factors. Using a geographic information system (GIS), these index values can be mapped and analyzed to portray areas of potential habitat for the species. It is important to note that modeling results do not show the actual occurrence of the species.

 

    How is the Sagebrush Ecosystem Program using HSM?

    The State of Nevada has worked with the U.S. Geological Survey to develop a habitat suitability model for greater sage-grouse in Nevada. The model uses sage-grouse telemetry location data and extensive environmental data (vegetation communities, topographic indices, elevation model, water resources, and human activity factors) as inputs to predict suitability. The results of the habitat suitability model were then used to build seasonal habitat suitability index (HSI) maps, which are used in the Conservation Credit System (CCS), and a composite HSI map.

    The Greater Sage grouse habitat management category map was developed from habitat suitability modeling efforts and the resulting HSI maps to represent habitat areas at the landscape scale and the importance. The Sagebrush Ecosystem Council formally adopted the December 2015 revision to the Nevada Management Categories at their December 11, 2015 meeting.  This revision included updated habitat selection modeling by the USGS, updated lek information in the space use modeling component, the addition of a major road and urban area mask, and a reduction to the extent of the management categories to the Biologically Significant Units.  In addition, the state has updated terminology to Priority Habitat Management Areas (PHMA), General Habitat Management Areas (GHMA), and Other Habitat Management Area (OHMA) to align with Federal Land Use Plans. This map is used in the CCS, for management of Greater Sage-grouse in Nevada at the state and federal level, and to support conservation planning decisions.  The composite HSI map and the management category maps can be found here.

     

      Nevada Maps Spatial Data

      The GIS shapefiles for the seasonal and composite habitat suitability maps as well as management categories for sage-grouse in Nevada and northeastern California developed by the USGS and the Nevada Sagebrush Ecosystem Program are available here (Coates et al. 2014).  Included is a layer file to symbolize the data following the state's format.  Please note there is an August 2014 version and March 2015 version available.  The methods to produce both maps are the same, but the August 2014 version used the 2013 lek database and the March 2015 version used the 2014 lek database.  Please review the metadata as it describes the methods for developing this layer and use the Coates et al. 2014 citation that is listed in the metadata when referencing the data.  As well, please reference the appropriate date version when using/presenting the data.

       

        USGS Open File Report

        This peer-reviewed report presents the process for developing spatially explicit maps describing relative habitat suitability for sage-grouse in Nevada and northeastern California. Maps depicting habitat suitability indices (HSI) values were generated based on model-averaged resource selection functions informed by more than 31,000 independent telemetry locations from more than 1,500 radio-marked sage-grouse across 12 project areas in Nevada and northeastern California collected during a 15-year period (1998–2013).