Nebraska Game and Parks Commission


Date of this Version



Simpson, R. and R. Schneider. 2014. Habitat Assessment for Nebraska's At-risk Species: Descriptions of Species Models Used in the CHAT (Crucial Habitat Assessment Tool) Species of Concern Data Layer. Nebraska Natural Heritage Program, Nebraska Game and Parks Commission.


As part of an effort across the western U.S. states led by the Western Governors’ Association, the Nebraska Game and Parks Commission synthesized information related to habitat for at-risk native species and natural plant communities. The result, submitted to the WGA in the fall of 2013, is coarse-scale, landscape-level information that can be used by anyone for land-use planning. The product of this west-wide collaboration is called the Crucial Habitat Assessment Tool (CHAT). The information, provided through an online GIS-mapping tool, is non-regulatory and gives project planners and the general public access to credible scientific data on a broad scale for use in project analysis, siting, and planning.

In the CHAT data and map product, the landscape is divided into one-square-mile hexagons, and values ranging from 1-6 are assigned. The value for the hexagons is based on the values from five contributing data layers, representing large intact blocks of habitat, wetlands, natural communities, and species of concern, respectively. The values for each one-square-mile hexagon in each of the contributing data sets are also available in the CHAT product.

This document focuses on the Species of Concern data layer and specifically on models which were incorporated into the data layer. While documented occurrences of species of concern were used when available, survey data is limited. Distribution models were used to help fill in the gaps between survey locations. The models help identify areas which may have suitable habitat and may be occupied by at-risk species.

Included in

Biodiversity Commons