Climate Change Impacts on Montane Biodiversity

Montane ecosystems, characterised by steep elevational gradients and unique microclimates, harbour a disproportionate share of global biodiversity. Rising temperatures, altered precipitation regimes and shifts in cloud immersion are driving fundamental changes to species’ distributions, community composition and ecosystem functioning. Many montane taxa, adapted to narrow thermal envelopes, have responded by migrating upslope, yet the limited availability of suitable habitat near summits has resulted in range contractions and heightened extinction risk. Altered patterns of cloud cover diminish moisture inputs critical to cloud-dependent forests, exacerbating drought stress and undermining habitat resilience. Changing climatic envelopes also disrupt ecological interactions, including pollination, seed dispersal and competition, leading to cascading effects across trophic levels. In addition, species at lower elevations colonise montane sites, promoting biotic homogenisation and undermining endemism. The net result is increased turnover of species assemblages, loss of unique genetic lineages and reduced ecosystem services such as water regulation and carbon storage. Effective conservation strategies require integration of empirical field experiments with predictive modelling, coupled with adaptive management and protected-area realignment to accommodate shifting climatic refugia. Cross-disciplinary approaches that blend physiological tolerance studies, long-term monitoring and remote sensing are essential to anticipate vulnerabilities, guide restoration efforts and safeguard these high-altitude biodiversity hotspots under future climate scenarios.

Research from Nature Portfolio

A large-scale transplant experiment across Central American mountains has empirically demonstrated that most tropical montane epiphytes are confined to narrow elevational bands and cannot tolerate warmer, drier conditions. Projections based on near-future temperature scenarios indicate that under moderate to high emissions up to one-third of species risk extinction, while substantial population losses are expected across multiple sites. This work provides the first direct field evidence of extinction risk in tropical montane flora, informing assessments of vulnerability and guiding conservation prioritisation.

In the Colombian Andes, comparative trials of dominant montane and lowland tree species revealed that just over half of montane taxa maintain growth under their upper thermal limits, whereas the remainder experience dramatic declines. Conversely, lowland species consistently outperform montane congeners at higher temperatures, signalling a competitive shift that drives community homogenisation. These findings elucidate the interplay between physiological tolerance and biotic competition in shaping forest composition under warming, emphasising the need to protect thermally sensitive high-elevation species and manage potential incursions.

Climate Change Impacts on Montane Biodiversity publication trend

The graph below shows the total number of articles in climate change impacts on montane biodiversity across all publications each year (not limited to Nature Index journals).

Technical terms

Elevational gradient: The change in environmental conditions and species composition along a slope from lowland to summit.

Montane cloud forest: A high-elevation forest ecosystem characterised by persistent low-level cloud immersion, high humidity and unique assemblages of moisture-dependent species.

Species turnover: The rate at which species are lost from or added to a community over time, often driven by environmental change.

Physiological tolerance: The range of environmental conditions, such as temperature and moisture, within which a species can survive and reproduce.

References

1. Experimental evidence of climate change extinction risk in Neotropical montane epiphytes. Nature Communications (2024).
2. Heterogeneous thermal tolerance of dominant Andean montane tree species. Communications Earth & Environment (2025).
3. Impacts of anthropogenic climate change on tropical montane forests: an appraisal of the evidence. Biological Reviews (2023).
4. The climatic drivers of long‐term population changes in rainforest montane birds. Global Change Biology (2023).
5. Multi-decadal trends of low-clouds at the Tropical Montane Cloud Forests. Ecological Indicators (2024).