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| Aim Climate change can lead to decreased climatic suitability within species’
distributions, increased fragmentation of climatically suitable space, and/or
emergence of newly suitable areas outside present distributions. Each of these
extrinsic threats and opportunities potentially interacts with specific intrinsic
traits of species, yet this specificity is seldom considered in risk assessments.
We present an analytical framework for examining projections of climate
change-induced threats and opportunities with reference to traits that are likely
to mediate species’ responses, and illustrate the applicability of the framework.
Location Sub-Saharan Africa.
Methods We applied the framework to 195 sub-Saharan African amphibians
with both available bioclimatic envelope model projections for the mid-21st
century and trait data. Excluded were 500 narrow-ranging species mainly from
montane areas. For each of projected losses, increased fragmentation and gains
of climate space, we selected potential response-mediating traits and examined
the spatial overlap with vulnerability due to these traits. We examined the
overlap for all species, and individually for groups of species with different
combinations of threats and opportunities.
Results In the Congo Basin and arid Southern Africa, projected losses for
wide-ranging amphibians were compounded by sensitivity to climatic variation,
and expected gains were precluded by poor dispersal ability. The spatial overlap
between exposure and vulnerability was more pronounced for species projected
to have their climate space contracting in situ or shifting to distant geographical
areas. Our results exclude the potential exposure of narrow-ranging species
to shrinking climates in the African tropical mountains.
Main conclusions We illustrate the application of a framework combining
spatial projections of climate change exposure with traits that are likely to
mediate species’ responses. Although the proposed framework carries several
assumptions that require further scrutiny, its application adds a degree of realism
to familiar assessments that consider all species to be equally affected by
climate change-induced threats and opportunities. | |
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