Ice in Yamaatyn

When tectonic plates smash into each other, they push the Earth’s crust higher and higher, forming mountains. Some mountain ranges, like the Himalayas, are still growing. Others, like the Appalachians, saw their heyday hundreds of millions of years ago and have been weathering away ever since. Volcanoes also form mountains and periodically erupt – scraping clear the landscape.

On a mountain, weather and the organisms that live there rapidly change as elevation increases. As temperatures get colder, tree species change, and then become scarcer before disappearing entirely. At the top there may be nothing but snow and ice. But even these bleak landscapes are home to a diverse array of plants and animals adapted for that environment.

Until recently, mountain habitats have been largely protected because of their inaccessibility. As people have moved into the mountains to live, for recreation and to obtain valuable resources such as timber, mountain ecosystems around the world have been subject to degradation and destruction.

Two snow leopards successfully collared in Nepal

Scientists successfully collared two snow leopards in Western Nepal—a feat that will help researchers learn more about this elusive and vulnerable species. The satellite GPS collaring of these big cats brings Nepal’s tally of collared snow leopards to eight.

A snow leopard looks to the right wearing a satellite collar and sitting on a rocky slope

Why They Matter

  • Water for People

    Mountains capture water from the atmosphere and store it as snow and ice that supplies streams and rivers throughout the year. Half the world’s population depends on mountains for their drinking water or hydroelectric power.

  • Unique Biodiversity

    Because mountain habitats can change quickly as elevations increase, they are often home to a greater diversity of plants and animals than nearby lowlands. On some mountains, especially at medium elevations in warmer latitudes, many species are endemic, meaning that they are found nowhere else in the world.


Trekkers walking

Trekkers walking on the Langtang trail in Nepal with snow capped mountains in the background. Trekking plays a vital role in the local economy, but also has significant impact on the local environment.

Climate Change

Glaciers—layers of ice and snow compressed over thousands to millions of years—are often found high in the mountains. Runoff from glaciers provides water to many people. But climate change is causing many of these glaciers to shrink, which could lead to floods and water shortages and contribute to sea level rise that will destroy coastal communities.


People use mountain trees for firewood and other timber products. But unsustainable logging is a problem in many mountain forests. In addition, mountain forests are often lost to expanding agriculture or mining ventures that destroy precious habitat.

Tourism and Development

Globally, one out of eight people live in mountains and many others visit them each year. But mountain habitats are often destroyed to make way for roads, hotels and other developments (such as hydropower). Visitors can damage ecosystems if they trample plants or cart them away.

What WWF Is Doing

Udzungwa Mountains

Supporting Protected Areas

Securing mountain ecosystems within parks and other protected areas can help to preserve their valuable plants and animals for future generations. Protected areas have proved key to the preservation of some species, such as the mountain gorillas of the Virunga Mountains in the Democratic Republic of Congo. WWF works to create and support protected areas around the world.

Addressing Climate Change

Climate change will bring alterations to all ecosystems, including those on mountains. WWF advocates for an international climate agreement and promotes energy efficiency and renewable energy. We work to stop deforestation and develop strategies for adaptation—especially among vulnerable communities and fragile ecosystems such as mountains.

Supporting Sustainable Livelihoods

Many mountain regions, such as the Eastern Himalayas, are densely populated. These populations put pressure on mountain ecosystems. WWF works to conserve biodiversity in mountain landscapes while promoting sustainable livelihoods for the people who live there.