by Elizabeth Medford
While it has been recognized in the past that climate change will have impacts on biodiversity, many approaches ignore the differences between species that will increase or reduce their vulnerability. Foden et al. (2013) chose to address three different aspects of climate change vulnerability to account for species’ biological traits: sensitivity, exposure, and adaptive capacity. In combining these traits with the modeled exposure to projected climate change, the authors assessed the species with the greatest relative vulnerability to climate change. These methods were applied to each of the world’s birds, amphibians, and corals. The authors also identified the geographic areas in which the most vulnerable species are concentrated. These included the Amazon basin for amphibians and birds, and the Indo-west Pacific for corals. The aim of Foden et al. is that the results from this study will help to better protect vulnerable species from the dangers of climate change. The data from this study can be used to devise more effective species and area specific conservation strategies.
Recently, anthropogenic climate change has become an official significant threat for vertebrate populations according to the Intergovernmental Panel on Climate Change (IPCC). The studies done by the IPCC however have been focused mostly on global assessments of potential climate change impacts. To more accurately identify the species most at rink from climate change Foden et al. incorporated species’ physiological, ecological and evolutionary characteristics with predicted climate change exposure. To identify the biological traits that determine species’ climate change vulnerability the authors held two workshops with over 30 experts in extinction risk over a broad range of taxonomic groups. These workshops resulted in over 90 biological, ecological, and environmental traits likely to influence climate change vulnerability. After consolidating these traits the authors finalized ‘trait sets’ including habitat specialization, narrow environmental tolerances, the potential for disruption of both environmental triggers and interspecific interactions, rarity, poor dispersal potential, and poor micro-environmental potential due to low genetic diversity. The authors study nearly 10,000 bird species, 6,000 amphibian species, and 800 warm-water reef-building corals because these taxonomic groups are well studied and include species from terrestrial, freshwater and marine biomes. Much of the trait data was gathered using online databases, experts’ knowledge and the International Union for Conservation of Nature’s (IUCN) Red List.
The results from this study assess relative vulnerability rather than absolute vulnerability to climate change, meaning that the results cannot be used to infer how many species will be impacted, nor vulnerability between taxonomic groups. Instead, the results can best be utilized to infer which species are likely to be at the greatest risk of extinction driven by climate change. The authors included both the total numbers of vulnerable species in a region and their proportion relative to all species occurring, in the hopes that areas containing the greatest number of highly climate change vulnerable species will be protected. The Amazon for example emerges as a region of utmost importance because of the high concentration of climate change vulnerable bird and amphibian species. Large numbers of highly vulnerable bird and amphibian species also can be found in Mesoamerica. For corals, the proportion of highly vulnerable species shows little spatial pattern, but with a slight concentration of such species in the Caribbean. The information garnered by Foden et al. is vital for large-scale conservation planning exercises but also illuminates that more detailed assessments are needed to fully understand climate change vulnerability.
Foden, W., Butchart, S., Stuart, S., 2013. Identifying the World’s Most Climate Change Vulnerable Species: A Systematic Trait-Based Assessment of all Birds, Amphibians and Corals. PlosOne Volume 8 Issue 6. Full paper http://bit.ly/1p5AcLG