NUSA DUA, Indonesia, April 15, Reuter - Tourists, reach for your cheque books.

The travel industry, environmentalists and officials from developing countries have decided people wanting to visit unspoiled wildernesses will have to pay much more.

"A lot of countries are selling their tourism too cheaply," World Wildlife Fund (WWF) Asian director Bruce Bunting told the annual conference of the Pacific Asia Travel Association.

Tourists were travelling far and wide in search of isolated natural beauty, he told the conference which ended at the weekend.

"It makes perfect sense that visitors should be willing to help pay the costs of maintaining conditions," he said.

Much of the world's remaining wilderness is in poor countries where cash is a higher priority than conservation.

The travel industry must show governments and people of the developing world that preserving forests for tourism is a better economic bet than cutting them down for a one-off profit, speakers stressed.

A Philippines delegate described efforts to set up a marine park in El Nido on one of the archipelago's southwestern islands dominated by commercial fishing companies and a logging firm with strong political backing.

"It is a Third World classic -- the clash of vested interests of big business, conservationists and people on the very edge of subsistence," said Philippine Undersecretary for Environment and Research Celso Roque, now seconded to the WWF.

Conservationists would always lose unless they could come up with financial clout, Roque said, which conference speakers believed the tourist industry could provide.

"Despite the fears of conservationists, tourism and ecology need not be mutually exclusive," said Lisa Choegyal of Tiger Mountain Ltd, a pioneer in nature tours in the Himalayas.

"Financial imperatives and preservation ideals must be part of the same picture."

Higher entrance fees to national parks would allow governments to make more money from fewer tourists, keeping infrastructural needs down and generating cash for community projects and preservation, speakers said.

Rwanda's Parc National des Volcans charges 170 dollars to see gorillas in the wild. Just 6,000 visitors a year pump around 10 million dollars annually into the central African nation's economy, a consultant said.

Speakers warned against mass tourism in delicate areas. Firms competing for high-volume business were bound to cut costs, Choegyal said, "and environmental luxuries are the first to be cut by economic constraints."

Traditional life in Indonesia's overloaded resort island of Bali which hosted the conference was threatened by developers racing to make a quick buck at the expense of the environment, said the nation's tourist planning chief, himself Balinese.

"Developments around the world suggest investors are always short-sighted and the cost of environmental damage is not necessarily borne by investors but in fact is borne by the tax payers and the population at large," I Gede Ardika said.

A key to keeping wild areas intact is ensuring that tourist dollars filter through to locals.

"Local people will feel the urge to protect a tourism product only as much as they feel part-ownership," researcher Charles Tambiah said.

Roque pointed out that coral which attracted visitors to Cebu in the Philippines was being blasted apart by dynamite fishermen who gained nothing from tourism and needed to feed their families.

"Tourism as a spot of affluence and luxury amidst unmitigated poverty cannot be sustainable development," he said.

But tourism could provide an alternative income to poor people who would otherwise be cutting down forests or shooting wildlife to live, said WWF's Bunting. He described a project to hire villagers as guides in a Thai nature reserve.

"Many of the villagers had been poachers of wildlife in the park and so were very familiar with trails and watering spots... The animals they used to hunt and sell are now the same animals which visitors pay to see."

Speakers suggested tourists themselves could be encouraged actively to improve the environment in the developing world.

One U.S. travel firm sells tours to the Peruvian ruin of Machupicchu that include cleaning up the trail to the remote site high in the Andes, a tour operator said.

"There's a lesson in that for this industry, that people will spend two thousand dollars to spend their vacation picking up trash," he said.