Climate‐driven range shifts of montane species vary with elevation

Abstract

Aim In response to warming, species are shifting their ranges towards higher elevations. These elevational range shifts have been documented in a variety of taxonomic groups across latitude. However, the rate and direction of species range shifts in response to warming vary, potentially as a consequence of variation in species traits across elevation. Specifically, diurnal and seasonal climates are often more variable at higher elevations, which results in high‐elevation species that have broader thermal physiologies relative to low‐elevation species. High‐elevation species that are thermal generalists might not need to move as far to track their thermal niche as low‐elevation thermal specialists. We investigated whether rates of range shifts varied systematically with increasing elevation across taxa and regions. Location Sixteen montane regions world‐wide. Time period 1850–2013. Taxon Nine hundred and eighty‐seven species of plants and animals. Methods We gathered published data on elevational range shifts from 20 transect studies comparing historical and recent distributions and examined how rates of range shifts changed across elevation. Specifically, we performed a meta‐analysis to calculate the pooled effect of elevation on species range shifts. Results We found that rates of range shifts show a negative relationship with elevation such that low‐elevation species have moved upslope farther than high‐elevation species on the same transect. This finding was primarily a result of shifts in the upper range limits. We also found that 28% of species shifted downslope against predictions, but elevation did not show a relationship with downslope range shifts. Main conclusions Idiosyncratic range shifts will significantly alter montane ecological communities, which are home to some of the greatest biodiversity on Earth. Our results demonstrate that species range shifts vary with elevation and might be a consequence of differences in species traits that also vary along montane gradients.

Ecological Correlates of Elevational Range Shifts in Tropical Birds

“…The overall shift rates generally lag behind those expected based on the local temperature increase and lapse rate (Forero-Medina et al, 2011b). Moreover, while most species tend to shift upslope as predicted, between a third and a fifth of species shift downslope (Forero-Medina et al, 2011b;Freeman and Class Freeman, 2014;Freeman et al, 2018b;Mamantov et al, 2021). Such variation suggests that elevational shifts are complex and site or species-specific (Fadrique et al, 2018), and that species are not simply tracking shifting climate envelopes.…”

“…Among animals, elevational shifts have been most widely documented in birds, with studies across the tropics revealing consistent upslope movements in bird communities (Freeman and Class Freeman, 2014;Freeman et al, 2018b;Neate-Clegg et al, 2018, 2020b). Yet, despite the prevalence of these elevational shifts, there is significant variation in the rate at which species have shifted between regions and between species (Freeman et al, 2018a;Mamantov et al, 2021). The overall shift rates generally lag behind those expected based on the local temperature increase and lapse rate (Forero-Medina et al, 2011b).…”

Long-term changes in populations of rainforest birds in the Australia Wet Tropics bioregion: a climate-driven biodiversity emergency

“…Globally, increasing evidence indicates that species are responding to climate change by shifting their geographical distributions [27]. These shifts often follow warming temperatures poleward and upslope [6,10]. Montane species are of particular concern in this respect, as they are expected to experience reduced distribution area, increased population fragmentation, and increased risk of extinction with upslope movement into ever-smaller area [28,29].…”

“…However, in all studies, the level of predicted impacts is disturbing with potential losses of between 15-35% of all species [3,4]. The projected impact of climate change is expected to be especially severe in mountain ecosystems with up to 84% of mountain species globally facing a high extinction risk [5][6][7]. Mountain regions provide a host of critical ecosystem services [8], support a disproportionate amount of the world's biological diversity and, harbour many phylogenetically unique species [5,[9][10][11][12].…”

Environmental Heterogeneity Leads to Spatial Differences in Genetic Diversity and Demographic Structure of Acer caudatifolium

“…Although the seeds of A. caudatifolium have wings that aid spreading, maple seed dispersal is unexpectedly distance-limited and aggregated [ 35 ]. The warming-driven downslope range shift is also more limited than the upshift [ 36 ], resulting in the limited passage of mountainous maples through the lower basins and lowlands and interrupting gene flow between the Datun volcano group and the southern populations.…”