By Alex Kirby BBC News Online environment correspondent, in Nairobi

The man credited with saving Kenya's elephants from destruction by ivory poachers more than a decade ago says the species is at risk across the world.

Dr Richard Leakey, who as director of the Kenya Wildlife Service (KWS) introduced stringent anti-poaching measures in the late 1980s, says a new market for ivory has arisen since then.

It's entirely plausible that 80% of wild Asian elephants have gone in the last 10 years

Dr Richard Leakey

He says Asian elephants have suffered horrendous losses in the last decade. And he fears that African elephants will be targeted next.

Dr Leakey, who left KWS in 1999, was speaking in an interview with BBC News Online in Nairobi.

He said: "It's entirely plausible that 80% of wild Asian elephants have gone in the last 10 years. There are now only about 35,000 left, maybe 30,000."

He said: "A large part of the success of the ban on the international ivory trade introduced in 1989 wasn't a piece of legal paper - it was a change in public attitudes.

"That was why the bottom fell out of the trade."

New found wealth

He said that the modern wealth explosion in China was partly to blame.

"In 1989 China was a poor country, but it's grown phenomenally. Since the earliest emperors, ivory has been a mark of value in China.

"Now, in effect, you've got a hundred million emperors, with traditional ivory carvers on their doorstep in places like Hong Kong.

"I think that will create a demand that will be fed by an illegal supply."

With ivory now fetching $150 a pound in south-east Asia, he said, there was an inevitable "suction" effect that would encourage renewed poaching in Africa.

"Whether or not there's a trade ban is irrelevant. There's a huge new market, and we have to return to the trenches.

"That means Africa is going to have to protect elephants effectively again - more money, more people, more guns."

Dr Leakey was careful not to stigmatise the Chinese.

"I don't think the government in Beijing wants to be responsible for the elephants' extinction", he said. "The Chinese are very practical people, they have a credible environmental record.

"Tell them the facts, get Chinese non-government organisations, which are good, to create the public attitudes which made such a difference in the West.

"The conservation community must reach out to China. As for the poachers, I'd go back to my old policies - hit them hard."

Mass extinction

But it is habitat loss, not poaching, that Dr Leakey blames for the threat he sees to many species. Last year, he said in a speech that the Earth was probably approaching a sixth mass extinction.

He told BBC News Online: "From palaeontology there are precedents for loss of biodiversity, and they're pretty catastrophic.

"Habitat loss through human pressure and climate change is having - and will have - fantastic implications.

It's quite wrong to propose a doomsday scenario, but I think a wake-up call is required

Dr Richard Leakey

"I don't know the timescale, but from the geological record we know that climate change moves along pretty fast once it gets going.

"All the signs are that it's going very fast now - and we're not responding quickly. "The next 50 years will be pretty dramatic.

"It's quite wrong to propose a doomsday scenario, but I think a wake-up call is required. For tropical countries like Kenya, beset by problems like poverty and the balance of trade, rising to the challenge is a tough call.

"But this is one world, and its health is important to all of us.

"The isolationist view of the US on climate change and other environmental conventions is very dangerous."