New to work, researchers warn that since 2001 a vast expanse of mountain woodland has vanished, a stretch larger than the state of Texas by every year that passes. The trend is alarming and continues to accelerate as human activity edges into highland regions that were once remote. Across many mountain ranges, the loss compounds an existing pattern of habitat reduction, driven by the steady pull of development, farming, and resource extraction that ignores the ecological value perched above the lowlands.
In total, scientists estimate that about 78 million hectares of montane forest have disappeared over roughly the last twenty years. That figure translates to more than seven percent of the world’s remaining montane forests. The leading culprits behind this decline are clear and concentrated: unsustainable logging that strips away the canopy, agricultural expansion that erodes the forest edge, and fires that sweep across fragile montane ecosystems with increasing frequency and intensity. The consequences echo through the corridors of life that depend on these forests for shelter, food, and climate stability.
The mountains cradle an immense portion of biodiversity, hosting more than 85 percent of the planet’s birds, mammals, and amphibians. These elevated habitats naturally offered a buffer when compared with lower terrains, largely because the rugged terrain limited access and extraction. Yet those protections are eroding as human activities spread into remote highlands and as protections in lowland forests are strengthened, creating pressure on mountain ecosystems. The cumulative impact threatens not only individual species but the intricate ecological networks that sustain them, from pollination to seed dispersal and disease regulation.
More than four-tenths of total forest loss occurs in tropical montane forests, a category long recognized as a biodiversity hotspot. In these areas, the consequences ripple outward, challenging conservation efforts and elevating risk for endangered species. A researcher from a prominent southern university explained that the encroachment into regions once valued for terrestrial biodiversity is particularly acute in tropical zones. The primary drivers remain diverse forms of agriculture and expansions in forestry, with local and regional pressures converging to reduce habitat quality and connectivity high in the mountains, where fragile communities of plants and animals rely on precise ecological conditions to survive.