our years ago, when I was a 20-year-old anthropology student, I went into a bookshop one rainy day, and came across a poem about Peru's Manu National Park - in one of the remotest parts of the Amazon rainforest - describing how it 'throbbed with wildlife'.

I was already keen to get first-hand experience of environmental and social issues in Amazonia and the phrase captivated me. What can a place be like that 'throbs' with life? I had to go.

I started researching the area and learned about the Nahua people, only 250 of whom still survive. Until about 20 years ago they had fiercely rejected all attempts at contact with the outside world. In March 1982, their spears and arrows drove back an elite force of the Peruvian military that was looking into the possibility of building a road through the park. The road was never built.

World turned upside down
They also fought against loggers coming into their territory. But in 1984 loggers captured four Nahua, who were taken to the local town before being sent back to their villages. They brought back devastating epidemics of respiratory diseases that wiped out over half the people within one year. The Nahua became increasingly dependent on outsiders for medical support and goods like salt, clothes, medicines, guns and motors. In just 20 years, their world has been turned upside down.

I found four student friends of mine - three girls and a guy - who wanted to come with me and try to live with the Nahua. I then set out on a reconnaissance trip to ask them if we could come. It was crazy: I spoke no Spanish (the language of Peru), let alone Nahua. All I had was the first name of a possible contact, Frederico. Eventually I found him, and the two of us travelled for four days in a dugout canoe to meet the Nahua.

Complex situation
They held a communal meeting and agreed that Frederico, my friends and I could come back. So we spent three months living and working with the Nahua in their village, Serjali. We formed a great relationship with them and investigated the social and environmental impact of mahogany logging in their territory. We grew to understand the complexity of a situation in which the Nahua recognized the bad effects of logging on the forest and its wildlife but also needed to allow a small amount of it in order to be able to buy the modern goods they had come to depend on.

It was not just a one-way learning experience - we were able to inform the Nahua that although they didn't know it, they lived within a reserve and logging by outsiders was illegal.

A year later, after I graduated, I returned to Serjali to discover that Nahua territory had been invaded by 250 loggers. The Nahua had tried to protect their land, only to be threatened with death. So, armed with what we had told them about the reserve, they travelled for over three weeks to protest to the local authorities. Yet the central government hadn't even acknowledged their complaints and the loggers were continuing to fell trees.

The Nahua asked for my help and I went with them to appeal directly to central government. In response, the authorities sent a high-level commission to Serjali and set up temporary guard posts at the entrance to the threatened land. The loggers eventually withdrew from the reserve, promised never to return, and paid compensation to the Nahua.

My colleagues and I set up an organization in Peru called Shinai Serjali (literally: 'To think about Serjali') to continue helping the Nahua. We worked with them to make detailed maps of their territory, training them to use GPS (global positioning system) devices. They are now using these maps to claim a land title that will give them greater legal protection from loggers and other industries; in an unprecedented move, they have recently used the title to modify a concession for oil drilling that was illegally encroaching on their territory.

We also helped them put up signposts at key entry points to their territory announcing that it was theirs. Many loggers now turn back when they see them, and this has given the Nahua the confidence to send more persistent loggers away. We have also taught them to use digital cameras so that they were able to take pictures of another mass invasion, and report it via e-mail to the nearest authorities.

Greatest challenge
Life for the Nahua is changing rapidly; they are facing new and increasingly difficult choices. Our short-term objective is to provide them with security from external pressures and raise their awareness, so that they can make critical decisions about their own future in their own time and on their own terms. One of the greatest challenges is to ensure that they have the capacity to communicate these concerns to the outside world and deal effectively with government, without our help.