Philip Bubb charts the disappearance of the word’s vital cloud forests, and suggests ways of conserving them

Cloud forests – which occur so high up tropical mountains that they are frequently permeated by clouds and mist – are much rarer than lowland rainforests. Perhaps best known as the habitat of the mountain gorillas in Africa, they are a vital and threatened part of the mountain environment of over 60 countries, including many tropical islands.

You are immediately struck, when you enter one, by how cool and wet it is. Water is likely to be dripping all around you, and you are surrounded by a huge abundance of orchids, mosses and ferns, weighing down the trunks and branches of every tree. The forests act as sponges, capturing water from the clouds as they touch the vegetation. The water – either cascading down the mountainside in waterfalls or soaking into the ground to reappear in streams further down – is vital for people both in the mountains and in the lowlands below.

This water supply is especially valuable in areas of little rainfall, where there is a pronounced dry season. Even when dry areas – such as parts of East Africa, and rainfall-shadow valleys in Central America and the Andes – are getting no rain, water is still being captured and supplied from the cloud forests above. The 2.5 million people of Dar es Salaam, for example, depend on water from the forests of the Uluguru mountains, both for drinking and for hydro-electric power.

When the forests are removed, no plants remain to capture water from the clouds. They can also no longer act as a cushion between the surface of the soil and the impact of heavy tropical rainfall – so serious soil erosion and landslips occur.

Cloud forests also contain high concentrations of their nations’ – and the world’s – biodiversity. They cover less than 1 per cent of Mexico, for example, but contain about 12 per cent of its plant species.

A high proportion of their species are endemic. A survey of a single cloud forest ridge in western Ecuador found about 90 plant species apparently confined to an area of just 20 square kilometres. A third of Peru’s 272 endemic species of mammals, birds and frogs are from cloud forests.

The forests are a priority for biodiversity conservation because, even if only a small fragment of one remains, there is a high chance that it contains unique endemic species. These can include crucial gene pools of wild relatives of such major crops as tomato, avocado, potato, peppers and medicinal plants. The Cascarilla tree, from which the anti-malarial drug quinine was extracted, is native to the cloud forests of Ecuador.

Even though cloud forests grow on steep slopes and in relatively inhospitable climates, they are increasingly being cleared and degraded. They only survive in the least accessible areas – islands surrounded by farmed mountain landscapes. As mountain communities grow and roads open up new areas, pressures to clear more forests increase.

Poor farming practices can also drive deforestation; as soils become exhausted and unproductive, farmers clear new areas. The clearance of cloud forests for cattle pasture and the growth of illegal drugs, such as opium, are particular problems in the northern Andes. They are also widely exploited for fuelwood and charcoal.

Besides these threats, which are faced by all tropical forests, cloud forests are uniquely vulnerable to global warming. Climate change and severe El Niño events have already been found to increase the height at which clouds form. As clouds move up the mountains, forests are left exposed and become drier. If the forests are already at the mountain top, they will have nowhere higher to go and will become extinct.

Felling rainforests for pasture in nearby lowlands poses a similar threat to cloud forests. Cattle pastures are warmer and drier than rainforests and so less clouds form above them.

These two process have been linked to the drying out of the Monteverde cloud forest in Costa Rica, causing the extinction of species which need water. Half of the of 50 frog species, including the golden toad, disappeared during an El Niño event in 1987: only five have re-appeared.

Cloud forests have been given some form of protected area status – such as national park or community forest – in many areas, often for their crucial role in supplying water as well as to conserve biodiversity. But large areas have no, or ineffective, protection.

The fundamental problem is that the value of cloud forests is not fully appreciated, allowing them to be destroyed by inappropriate farming methods, and by state-sponsored infrastructure projects such as mining and roads.

Addressing immediate needs is one way to secure their future. Poor local people need to be able to produce enough food and to gather enough fuelwood to support their families. It is not realistic to ask them to stop cutting down cloud forest while they have no other ways of producing what they need to survive. Developing and implementing sustainable farming systems, as has happened in some areas, gives them a choice about whether they want to conserve their forests. It then becomes possible to raise awareness of the importance of cloud forests and to find local ways of conserving them..

Another approach is for governments or private organizations to establish reserves where felling is forbidden. But, once the immediate destruction has been halted, viable alternative livelihoods must swiftly be developed.

Cloud forests are valued by downstream users of water, by tourists, by scientists and by people concerned with the extinction of species. The value these people place on them must be converted into practical support for those who live there, upon whose stewardship the forests depend.

In one example, the water company in the Costa Rican city of Heredia and the owners of a hydro-electric plant – which both use water from the cloud forest – pay a fee to support conservation. The money is used for the running costs of a reserve, and for a re-forestation programme. In other situations, such revenue could be used to pay for a community development fund to support local people in sustainable livelihoods which do not involve clearing the forest.

Local and national conservation strategies are needed. But first it is necessary to know where cloud forests are and why they are important. In many countries, however, most sites have hardly been surveyed.

Individuals and organizations in every country are championing their cloud forests. They need international support, including funding, training and information on successful methods being used in other areas.

In 1999 the Tropical Montane Cloud Forest Initiative was formed by the UNEP-World Conservation Monitoring Centre, WWF, IUCN and the UNESCO International Hydrological Programme. It raises international support and promotes conservation action plans in regions with cloud forests. UNEP-WCMC is providing information on the worldís cloud forests and training in developing conservation strategies.

As individuals we can support cloud forest conservation by visiting them as tourists or as concerned leaders and decision-makers. Visiting and publicizing these magical places – green cathedrals of beauty and inspiration – will help to secure their future

Philip Bubb is an Adviser to the UNEP-World Conservation Monitoring Centre in Cambridge, United Kingdom.


This issue:
Contents | Editorial K. Toepfer | Saving the common land | Aiming high | Mighty, but fragile | Walking the talk | Regreening the slopes | For the people | High priorities | Natural beauty | Prospects for WSSD: Towards Johannesburg | Along a steep pathway | The height of trouble | Disneyland or diversity? | Path to discovery | On top of the issue | Peak condition | Swimming upstream | Cloudy future

Complementary articles in other issues:
AAAS Atlas of Population and Environment:
Population and ecosystems: Mountains
AAAS Atlas of Population and Environment:
Population and ecosystems: Forests
Thomas Lovejoy: Tall trees and bottom lines
(Biological Diversity) 2000

Complementary report:
Mountain Watch Report