Crucial Habitat Assessment

NVCHAT was developed under the guidance of the Western Governors’ Wildlife Council White Paper which provides common definitions of crucial wildlife habitat and recommendations to help states prioritize habitat to meet specific conservation objectives. Standardized definitions promote interstate consistency and compatibility and help address certain discrepancies that may exist along state borders. The recommendations for identifying crucial habitat provide a framework for data sources and analysis methods that all states can implement to achieve consistent maps across the West.

Crucial habitat is represented by a relative, six-level ranking scheme, where 1 represents the "most crucial" habitat and 6 represents the "least crucial" habitat on the landscape. Crucial habitat ranks are in no way regulatory or legally binding and carry no value other than their relative weight against each other (i.e. a rank of 1 has no inherent meaning other than it is more crucial than a rank of 2). Crucial habitat ranks should be interpreted as the relative probability, or risk, that a high-priority species or habitat would be encountered in a given area.

NVCHAT has been the result of coordination and collaboration among 16 western state wildlife agencies working under the direction of the Western Governors’ Wildlife Council. The information provided by NVCHAT is intended to improve the understanding of Nevada-specific wildlife habitat priorities, as well as provide compatible information for interstate planning. NVCHAT is intended for landscape-scale planning and decision making in the early stages of the project planning process. The information provided by NVCHAT should not be used to make site-specific decisions and in no way replaces on-the-ground biological surveys or agency consultation. Data provided by NVCHAT does not represent the exact ecological value or condition of any specific point on the ground, but rather the aggregate wildlife habitat value of a given one square-mile mapping unit. Users are encouraged to consult with the Department on the proper use and interpretation of the information provided by NVCHAT, as well as how to obtain site-specific and/or species-specific wildlife resource information.

NVCHAT incorporates both confirmed (documented) species occurrence information and interpreted or modeled species distribution data. The absence of documented species occurrence information in a given mapping unit is simply a lack of data in that mapping unit and should in no way be interpreted as the documented absence of that species on the ground.

Crucial Habitat Analysis Input Layers

Crucial Habitat ranks represent an aggregated measure of the relative habitat value for important wildlife species in Nevada and provide information on areas that are expected to provide the ecological function necessary for continued health of wildlife populations or high biodiversity. Crucial Habitat ranks were developed using the following data categories as represented by the best available data layers in Nevada:

  • Habitat for Species of Concern

    Locations of Federally or State Listed Threatened or Endangered species, Candidate species, species protected under signed Conservation Agreements, other species of special concern. Key or Priority Habitat delineations of Species of Concern. Priority habitat areas based on species diversity, habitat intactness, and overlap with other crucial habitats.

  • Native and Unfragmented Habitat

    Areas that are contiguous, possess a high degree of intact core areas or diversity of natural habitat, or supply ecological function to meet wildlife objectives. These areas are unfragmented, or relatively unfragmented, by transportation routes, human habitation, industrial infrastructure, or other human-caused disturbances.

  • Wetland and Riparian Habitat

    Areas that represent unique environments and function to support animal and plant diversity with respect to wildlife objectives and connectivity. Spring/seep/cienega locations, wetland components from State Comprehensive Outdoor Recreation Plans, priority wetland and riparian areas identified in State Wildlife Action Plans, National Hydrography Dataset, and National Wetlands Inventory.

  • Habitat for Species of Economic and Recreational Importance

    Species considerations not otherwise included in Species of Concern. Areas recognized as important to meeting biological requirements and objectives of game species regulated by harvest.

Standard Terminology

  • AKN: Avian Knowledge Network
  • BLM: United States Bureau of Land Management
  • CCVI: Climate Change Vulnerability Index
    • EV: Extremely Vulnerable
    • HV: Highly Vulnerable
    • IL: Increase Likely
    • PS: Presumed Stable
  • CHAT: Crucial Habitat Assessment Tool
  • GAP: Gap Analysis Program coordinated by the USGS
  • GBBO: Great Basin Bird Observatory
  • GNIS: Geographic Names Information System
  • LI: Landscape Integrity as modeled by the NatureServe Landscape Condition Model
  • NAC: Nevada Administrative Code
  • NBC: Nevada Bird Count
  • NDOW: Nevada Department of Wildlife
  • NHD: National Hydrography Dataset maintained by the USGS
  • NNHP: Nevada Natural Heritage Program
  • NVCHAT: Nevada Crucial Habitat Assessment Tool
  • NWI: National Wetlands Inventory maintained by the USFWS
  • SERI: Species of Economic and Recreational Importance
  • SGCN: Species of Greatest Conservation Need (see also Species of Concern)
  • SOC: Species of Concern (see also Species of Greatest Conservation Need)
  • SWAP: Nevada State Wildlife Action Plan (revised 2012)
  • UNR: University of Nevada Reno
  • USFWS: United States Fish and Wildlife Service
  • USGS: United States Geological Survey
  • WGA: Western Governors’ Association
  • WGWC: Western Governors’ Wildlife Council