Grassland, Shrubland and Desert Ecosystems
Contact Information
  • Grassland, Shrubland and Desert Ecosystems
  • 333 Broadway SE. Suite 115
  • Albuquerque, NM 87102-3497
  • 505-724-3660
  • 505-724-3688 (fax)

SAVS: A System for Assessing Vulnerability of Species


Climate change impacts are increasingly apparent among species and ecosystems. To preserve habitats and conserve biodiversity, managers need tools which effectively identify the major consequences of climate change for persistence and management of species and ecosystems [Scanning the Conservation Horizon].

Shepard Glacier, MT, 1913 and 2005
Shepard Glacier in Glacier National Park, Montana as seen in 1913 (left) and 2005 (right)

RMRS has developed a System for Assessing Vulnerability of Species (SAVS) (view the research project) that quantifies the relative impact of expected climate change effects for terrestrial vertebrate species. The SAVS uses 22 criteria related to expected response or vulnerability of species in a questionnaire to provide a framework for assessing vulnerability to climate change. The questionnaire is completed using information gathered from published materials, personal knowledge, or expert consultation. The SAVS Climate Change Tool focuses solely on the effects of climate change for terrestrial vertebrate species. This tool aids managers by identifying specific traits and issues related to individual species vulnerabilities. Scores generated by completing a questionnaire are meant to be used to inform management planning. A comprehensive discussion of the development and application of this tool will be available from the RMRS General Technical Report [A System for Assessing Vulnerability of Species (SAVS) to Climate Change, in press]. Information regarding specific criteria for each question are provided as information pop-ups with the scoring template. Users may also find it helpful to review assessments conducted for species in New Mexico and Arizona and legacy project briefs for Fort Huachuca, AZ and Barry M Goldwater Range, AZ. We assume users will familiarize themselves with these documents before proceeding with the scoring process.


Using the SAVS Climate Change Tool

Twenty two predictive criteria form the basis of an easily completed questionnaire organized into four categories, habitat, physiology, phenology and biotic interactions. Each predictive criterion corresponds to a single question and represents vulnerability or resiliency. Scores are calculated for overall vulnerability and for each of the categories. There are three steps to the scoring process:

Mountain Quail
The distribution of 28 bird species, like this mountain quail in CA, moved an average of 116m upslope over a 26 year period corresponding to temperature increases.
  • Data gathering: Climate projections for the target region (i.e., exposure) are used to determine appropriate response selections for each question and are obtained from published studies, reports, or other analyses (see Resources). Species data is also needed to complete the questionnaire. Please refer to the Guidelines [in press] for conducting a species assessment.
  • Scoring: Select the appropriate response according to data gathered regarding species biology and future expected conditions. Indicate level of uncertainty for each question.
  • Calculate and apply scores: This tool generates an overall score that scales from -20 (most resilient) to +20 (most vulnerable) and scores for each category that scale from -5 to +5. Overall scores can be used to identify highly vulnerable (or resilient) species or to rank species according to their vulnerabilities. Categorical scores provide information on where species are most sensitive to future climate conditions or changes. In addition, scores may be used to identify critical management actions or areas of need for the preservation of species under changing scenarios. Uncertainty is represented as the percentage of questions with inadequate or conflicting information and is calculated to correspond with overall and categorical vulnerability scores. Uncertainty must be taken under consideration when evaluating vulnerability scores. Species with high uncertainty values may be candidates for further monitoring or research efforts.

Application of Results

  • Scores can be used to rank species by vulnerability and identify those which may require attention to prevent declines.
  • Scores can help identify areas and issues of greatest vulnerability for single species and inform the development of effective management strategies.
  • Scores may also be used to identify groups of species with similar vulnerabilities that may benefit from the same management action.
  • Add climate change vulnerability scores to current species assessments or management plans to improve identification of conservation targets.
  • Scores and scoring process may be used to initiate dialogue on climate change challenges and solutions for species' management.
Artic Fox Pup
Over the last few decades the range of the Red fox has expanded northward and upward, displacing the Arctic Fox (pictured) in North American Tundra Habitat. Boundary changes have been related to warming trends, which increases food availability for the competitively superior Red Fox.

Caveats & Restrictions

The effectiveness of this scoring method and the applicability of the information derived from this process depend upon the quality of data used to conduct the scoring process. Scoring may require substantial amount of input data both regarding species vulnerability and future climate scenarios [A System for Assessing Vulnerability of Species (SAVS) to Climate Change]. The scoring tool was designed to be applied at the scale of a management unit and to accommodate a single climate zone (i.e., a uniform set of climate projections). Additional regional climate information needs to be integrated into the scoring system for migratory species that spend a significant portion of their lives outside the targeted region

Scores are not weighed by the relative influence of various criteria and it is up to the user to determine the relative importance of individual criterion to species persistence. Scores, scaled from -20 to +20, represent relative vulnerability and are not an absolute or linear measure of vulnerability.

In addition, the quality and quantity of information varies for individual species. An uncertainty score is included to account for this variation. Uncertainty also exists in predictions for future climates, which can influence the outcome of the scoring process.