The Geospatial Habitat Assessment Toolkit (GeoHAT) is a set of ArcGIS geoprocessing tools designed to evaluate overall habitat quality under alternative landscape scenarios. The toolkit can be used to prioritize key habitat areas for protection or to identify equitable habitat areas to protect for various mitigation plans, e.g., to offset development.
Habitat is assessed based on its capacity to support thriving populations of a given species or suite of species. The process begins with identifying which areas in the landscape qualify as habitat (based on user input or by using statistical models included in the tool).
Once overall habitat area is established, each habitat patch, or contiguous clump of habitat, is isolated and assessed for its contribution to species support potential. Is it large enough? Is the patch shaped so that enough habitat is protected from edge effects?
Patches are also assessed based on their proximity and sensitivity to various threats such as urbanization, pollution, and traffic.
And finally patches are assessed based on their proximity to other patches and maintaining a connected network of habitat area. A given patch may be an important breeding patch (source of individuals) or a required stepping stone that enables individuals to reach other habitat patches.
Each patch is thus assigned values based on its geometry (size and shape), its level of threat, and its contribution to overall connectivity. The user can weight the relative importance of each of these to determine an overall quality score for each patch, thus allowing for the patches to be sorted in importance for protection. The overall score can also be used to identify patches that can equitably offset patches lost to development under mitigation agreements.
Tools included in the toolkit
- Habitat modeling
- Habitat patch creation and attribution
- Threat analysis
- Connectivity analysis
- Habitat prioritization
Powerpoint presentation on GeoHAT applied to the
South Fork of the Catawba Basin in central North Carolina: GeoHAT_2012_Nov_1_SFCatawba