Using Two Climate Change Vulnerability Assessment Methods to Prioritize and Manage Rare Plants: A Case Study

Natural Areas JournalShannon Still

Uinta Basin hookless cactus (Sclerocactus glaucus) is a rare cactus species found only in a small region in Colorado, and was one of the species included in this project. | Photo by Barry C. Johnston and the U. S. Forest Service.Climate change is a crucial factor to consider when assessing the health of any species’ population, but conservationists are left with the challenge of deciding exactly how to measure its potential impact on a given species. While multiple tools and approaches exist for this purpose, each has its strengths and limitations.

To evaluate 34 rare plant species' climate change vulnerability, NatureServe used the Climate Change Vulnerability Index (CCVI), and Dr. Shannon Still at the Chicago Botanic Garden used species distribution modeling (SDM). NatureServe and Still then compared their results to determine how these two widely used approaches for assessing climate change vulnerability may be applied in a complementary fashion. This article in Natural Areas Journal reports on:

  • The ways in which the CCVI and SDM are complementary
  • The implications of vulnerability assessment results for conservation management decisions
  • The limitations of vulnerability assessments

The CCVI provides predictions mainly based on a species' biological characteristics, such as life span, reproductive needs, and habitat. SDM, a method of analysis commonly used by the research community, provides a spatial prediction of how the species' range may shift in response to changes in climate. “The CCVI can help prioritize which species within an area may need protection, while SDM can identify where that protection should occur,” said Dr. Anne Frances, lead botanist at NatureServe and coauthor on the paper. 

However, vulnerability assessments do have their limitations, and these are equally important to consider when developing management plans.

“One of the biggest challenges when assessing a rare plant’s vulnerability to climate change is lack of information about species biology and current range. Plant species are not studied as well as animals, and their ranges and basic biology are often unknown,” Frances said.

Additionally, vulnerability assessments are based on assumptions and estimations about climate change and its impact, and that is a fundamental limitation to these methods.

“The assumptions and estimations are based on good scientific data, but they are predictions. Scientific research on the effects of recent climate change on biological species is relatively new and limited in scope,” Frances said.

When used individually, SDM and the CCVI can contribute valuable information to vulnerability assessments. Together, they provide separate, complementary sets of information that can greatly enhance species management plans.

This project was made possible by funding from the Bureau of Land Management Plant Conservation Program.

This synopsis was written by Karoline Oldham. Karoline is a Master's student at George Mason University, where she studies plant systematics and evolution under Dr. Andrea Weeks. She joined NatureServe this fall as our Botany Outreach and Communications intern, where she has focused primarily on promoting awareness of plant conservation issues in the United States.

NatureServe Author(s)


  • Still SM, Frances AL, Treher AC, Oliver L. 2015. Using Two Climate Change Vulnerability Assessment Methods to Prioritize and Manage Rare Plants: A Case Study. Natural Areas Journal 35 (1), 106-121.