Climate Change And Extinction Risk
The subject of climate change—in relation to how it affects animal species and how exploiting animals contributes to climate change—is a subject we have covered at great length on Faunalytics. It’s a huge topic and an important one to discuss. And we need to continue to understand it as it develops. Human-caused climate change (a good deal of which may be caused by factory farming) is a major threat to global biodiversity. By some estimates, more than a million terrestrial species may potentially be “committed to extinction” by 2050.
Many consider the IUCN Red List of Threatened Species from the U.N. to be a reliable standard for predicting and measuring the vulnerability of different species. As good as it is, however, there is concern that the Red List is not living up to its potential when it comes to detecting climate threats. Considering the Red List’s role as an early-warning system, being able to detect climate threats related to species extinction is crucial, especially now.
Researchers wanted to find solutions to the aforementioned problem. They also wanted to investigate the apparent lack of “empirical risk assessments that directly address […] extinction risks under climate change.” In this study, they used Red List criteria in a detailed assessment of extinction risk. Specifically, they wanted to know how quickly the Red List criteria can “identify a species as threatened by climate change and which criteria are crucial for early detection of risk.”
The researchers studied the frog Assa darlingtoni, a “short lived amphibian species for which climate change appears to be the major current threat.” They used a modeling approach that looks at species’ life history and habitat responses to projected climate scenarios. The frog lives in cool and moist areas. But, these areas are expected to warm in the coming years. The species’ range has been reduced over the last year from logging and forest clearing. Currently, most of their remaining habitat is protected.
The researchers found that the current population of A. darlingtoni includes about 1.7 million mature females. When modeled under a stable climate, the population looks like it would remain stable for 100 years. But, under all of the various future climate change scenarios, the population would only remain stable until 2040–2050. And then it would decline at varying rates for different scenarios.
The most severe projection sees A. darlingtoni as extinct by 2095. Other projections see the frogs remaining extant over the next 100 years, but with the total population being reduced by anything from 39% to 96%. Based on the IUCN Red List criteria, the frog could be listed as a threatened species as early as 2010 or as late as 2050, depending on the pattern of decline. Considering that the species qualifies for threatened status 40–80 years before potential extinction, the research suggests that “red list criteria perform reasonably well as an early-warning system” for climate change extinction risks.
For animal advocates, the results of this study can be seen as good news. The approach used by the researchers could be useful for “evaluating the sensitivity of the red list criteria to climate change impacts on species with more diverse life histories.” Further study of short-lived species using these models could help to advance the science in this area even more. As climate change pressures build, it’s important to be able to understand and model the threats. In this way, we can prevent as many species as possible from becoming extinct before it’s too late.