Desert Species and Climate Change
When we think of climate change — often called “global warming” — we tend to think of changes in weather patterns that are generally characterized and caused by an overall rise in global temperature. Rising temperature will almost undoubtedly lead to a cascade of disastrous events, such as a significant rise in water levels and/or a higher frequency of “natural” disasters. When we think of such consequences, we may think of the archetypical image of the polar bear on a lonely ice floe in An Inconvenient Truth, or other charismatic species like penguins who live in cold climates that might be acutely affected by the effects of warming. However, animals in cold or temperate climates are not the only one that might be affected by climate change. In fact, research is showing that desert species may be even more at risk.
In this study, researchers wanted to address a gap they saw in existing literature, where “models focused on changes in the species’ distribution fail to explicitly reflect the broad range of climate-induced stress,” and contemporary studies “rarely appreciate the quantifications of areas exposed to the different dimensions of climate change in combination, despite their different implications for biodiversity.” This is all just a complicated way of saying that there are many reasons why certain regions and species may be affected by climate change, and certain types of species may face numerous climate-related pressures all at once. Deserts, in particular, are often arid and relatively flat, and “harbour unexpectedly high diversity of species subject to a strong climatic control.” Because of a their evolution and adaptations, desert species are generally very well adapted to extreme temperatures, however, in spite of this, they may have different sensitivities, such as to temperature fluctuations or changes in precipitation patterns.
Looking at the Sahara in particular, the researchers wanted to answer four questions:
(i) which functional groups are more vulnerable to magnitude of climate change; (ii) which func- tional groups will likely be able to keep pace with predicted velocity of climate change; (iii) where are located the potentially most vulnerable areas? and (iv) how are the most vulnerable functional groups represented within the current protected areas network?
Using various computer modeling methods and a wide range of data for their inputs, the researchers found that the most vulnerable species are small mammals and lizards. Those species are potentially exposed to “changes in the magnitude and velocity of precipitation and also locally exposed to temperature changes.” In other words, more rain generally and more pounding rainstorms. Even though these are species that are adapted to hot and dry regions, they still live close to their “upper thermal limits,” and it’s unlikely that they can evolve or adapt to rapid climate change quickly enough. While they may be able to cope with a warming trend in the short term, it could mean that they would overspend energy and potentially compromise their chances for reproduction success.
For advocates, this study should give some pause for thought. As climate change predictions — and actual climate change-related weather events — seem to be becoming increasingly dire, understanding how different sub-climates are affected will be important information. What can advocates do about it? The answers may not be immediately clear from such a study, but the takeaway is quite simple: we need to recognize that climate change is a problem that will have different reverberations across the world, and if we want to mitigate those effects for animals, we’ll need to come up with a wide variety of strategies, not just a one-size-fits-all approach.