"This is good not only for nature, but for the bottom line," he told an audience including Spain's Crown Prince Felipe in a speech that urged wider action by businesses, governments and ordinary people to safeguard nature.

"The process of moving toward efficiency saves species, but it also cuts waste, provides jobs and boosts profits," he said. The IUCN groups governments, scientists and environmental organisations.

"I make a call to business around the world to include on their boards at least one non-executive director with knowledge and experience of the protection of the environment," he said.

"Not to do so is reckless, for it jeopardises both the sustainability of the business concerned but also the sustainability of the planet," he said.

Animals and plants are vital for human life, providing everything from food to medicines. Moosa said that private sector businesses usually had experienced accountants on their boards, but no environmental expert.

A slide show at the start of the congress in Barcelona gave grim statistics including that one species of bird in eight, one mammal in four and one amphibian in three were threatened with extinction.

It also said that 75 percent of fisheries were fully or over-exploited, and that every second a patch of land the size of a soccer pitch disappears from tropical rainforests. Fixing the problem is "essential to our very survival," it said.

Moosa, a former South African environment minister, said governments had to to more to combat climate change, blamed by the UN Climate Panel on emissions of greenhouse gas from human activities led by burning fossil fuels.

"America and industrialised nations must lead the way," he said. "We call for a binding and enforceable global emissions reduction regime which binds not only the developed countries but also nations like China, India, Brazil and South Africa.

Rising temperatures could push ever more species to extinction, cause more floods, droughts, disease and rising seas, according to the Climate Panel.

-- For Reuters latest environment blogs click on: http://blogs.reuters.com/environment/ (Editing by Richard Balmforth)