By Tim Hirsch
BBC environment correspondent
The potential for indigenous people to help curb the destruction of forests is being overlooked by the international community, according to a report.
Locals make great efforts to protect the plants and animals of the forest
When forest communities are given legal control over their own lands they are at least as effective in conserving wildlife as national governments.
The study argues that local people should be given more access to financial incentives to protect nature.
The group Forest Trends launched the report during talks in Geneva.
In countries as diverse as Brazil, India and Thailand, local communities have been given the right to control forest regions, sometimes after long legal battles.
Where this has happened, the report says people make great efforts to protect the plants and animals of the forest.
This is often because of traditional beliefs about the sacred status of the wildlife, or the importance of natural products such as herbal medicines in their cultures.
In contrast, many areas officially designated as "protected" by national governments exist as parks on paper only, because poorer countries lack the resources to enforce environmental protection and prevent illegal logging or other forms of damage.
When the time, labour and financial resources used by community groups to protect forests are added up, the report estimates that it amounts to between $1.2bn and $2.6bn.
This is about the same as the annual budget developing countries spend on protected areas, and two to three times the worldwide aid budget directed at forest conservation.
The study gives the example of 80 indigenous reserves in the Brazilian Amazon.
Satellite imagery of the area shows that conservation of the forest is at least as effective as officially protected areas, even though the Indian lands are often closer to the threats posed by expanding agriculture.
It also points to the ecological importance of sacred groves in Ghana, thought to be the living places of gods, where traditional taboos forbid farming or the cutting down of trees.
Forest Trends argues the efforts of these communities could be further strengthened if they were helped to reap financial rewards from products obtained from the forest in a non-destructive way.
Local people should be given more financial incentives
This could be done through the marketing of wood or botanical products made in a sustainable way which could attract a premium amongst consumers in richer countries, for instance.
The group is calling for the 59 countries currently negotiating the renewal of the International Tropical Timber Agreement to include indigenous people in the incentives available for forest conservation, from which it is claimed they have so far been excluded.
A co-author of the study, Sara Scherr, said: "Support for the conservation efforts of indigenous peoples and forest dwellers can help protect ecosystems and biodiversity across biological corridors and political boundaries.
"The people who live on the land are committed for the long term, particularly if they develop the professional capacity and enterprise skills that can help them earn a better living while continuing to protect the forests."