1000 E. University Ave.
Laramie, WY 82071
Below is an abbreviated version of the Wyoming Game and Fish Department's NSS ranking procedure. For more detailed information, click on the links provided.
Element 1 of the Congressional guidelines for State Wildlife Action Plans (SWAPs) specifies that each state must provide “information on the distribution and abundance of species of wildlife, including low and declining populations as the state wildlife agency deems appropriate, that are indicative of the diversity and health of the state’s wildlife.” These species have been termed Species of Greatest Conservation Needs or SGCN.
The Wyoming Game and Fish Department's (WGFD) SGCN designation process is based upon its Native Species Status (NSS) classification system. During the early 1980's, the WGFD conducted a series of analyses to identify species of special concern. A system was developed that used a matrix to evaluate a species’ status in relation to population (y-axis) and habitat variables (x-axis). In the 2005 Comprehensive Wildlife Conservation Strategy (CWCS),1 a 16-cell matrix was used for birds and mammals and a 9-cell matrix for fish, reptiles, amphibians, and invertebrates. An NSS rank was assigned for an individual species based on the intersection of the two most appropriate population and habitat conditions. For the purposes of the 2005 CWCS, species identified as NSS1, NSS2, NSS3, or NSS4 were considered to be SGCN.
Since that time, it was determined that using a separate matrix for fish, reptiles, amphibians, and invertebrates was too cumbersome, and a revised approach was created for the 2010 SWAP. The revised NSS matrix has 16 cells (see table below). The y-axis consists of population variables, which range on a continuum from populations declining with extirpation possible (row A) to populations that are widespread and expanding (row D). After identifying the appropriate row for a species population, the most appropriate limiting factor column is selected from the x-axis, ranging from limiting factors that are severe and worsening (column a) to limiting factors that are moderate and not likely to increase (column d). Limiting factors include habitat, human activity levels, genetics, invasive species, disease, environmental contaminants, and climate change.
This system cannot be used for classifying some species because necessary information is lacking. These species are placed in a separate status category as NSS Unknown (NSSU) until additional information is obtained. Species that receive an NSS rank of NSS1, NSS2, NSS3, NSS4, or NSSU were recommended to the Wyoming Game and Fish Commission to receive SGCN designation for the 2010 SWAP. NSSU species were recommended to receive the SGCN designation because obtaining a greater understanding regarding population numbers and distributions of these species is necessary in determining their conservation status, including responding to petitions for listing under the Endangered Species Act. Some species with naturally low numbers and limited distributions were not recommended to receive SGCN status if both the following qualifications were met:
1. The species in Wyoming is not experiencing known population declines or increasing threats, and
2. The species’ population is abundant and secure throughout its range.
Only species that are legally considered wildlife in Wyoming were evaluated for SGCN status. Wyoming Statute 23-1-101 (a) (xiii) defines “wildlife” as all wild mammals, birds, fish, amphibians, reptiles, crustaceans and mollusks, and wild bison designated by the Wyoming Game and Fish Commission and the Wyoming Livestock Board within Wyoming. Plants and invertebrates (excluding crustaceans and mollusks) are outside the jurisdictional authority of the WGFD and were not considered for SGCN status. To increase understanding about Wyoming’s invertebrates, a cooperative agreement was signed between the WGFD and the Wyoming Natural Diversity Database (WYNDD) in May 2010.
Limiting factors are severe and continue to increase in severity
Limiting factors are severe and not increasing significantly
Limiting factors are moderate and appear likely to increase in severity
Limiting factors are moderate and not likely to increase in severity
Population size or distribution is restricted or declining and extirpation is possible
Population size or distribution is restricted or declining but extirpation is not imminent
Population size and distribution is stable and the species is widely distributed
Populations are expanding in number and/or distribution and the species is widely distributed