Up to 5 per cent of Africa’s elephants are being slaughtered for their ivory each year, according to research which suggests that poaching threatens the animals with extinction despite a global ban on the sale of ivory.

More than 23 tonnes of illegal ivory were seized between August 2005 and last August, most of it from recently killed elephants. Scientists believe that the true weight of smuggled tusks is ten times greater.

This would mean that about 234 tonnes of ivory were exported from Africa that year and about 23,000 elephants were killed. Continued poaching on this scale would drive the species rapidly to extinction.

Samuel Wasser, of the University of Washington in Seattle, who led the study, said the seizures suggested that poaching was taking place on a scale unseen since 1989, when an international convention banned the ivory trade.

The trend is being driven by growing demand in the Far East, and organised crime is becoming increasingly involved, Dr Wasser said. The black market price of a kilogram of good quality ivory was about $100 in 1989, and had doubled by 2004. However, last year a smuggled kilogram, was fetching $750 (£395), raising the financial incentive for poaching.

Urgent action is needed to help countries such as Zambia to deal with the organised crime syndicates that are running the trade, Dr Wasser said. “If it really is organised crime that’s driving this, then the only hope we have of stopping it is to stop the ivory at the source. . . because once it’s in the international market, the trade is very hard to stop.

“If people realised what is happening, they would be ashamed to be part of the crisis. We don’t want to spend our time catching criminals, we want to stop the crime from happening.”

The figures are disclosed today in the journal Proceedings of the National Academy of Sciences. The study team said it was estimated that quantities of contraband, such as illegal drugs, seized by customs amounted to about 10 per cent of the total smuggled. “We conservatively assume that this percentage is also the case for ivory,” they said.

“Most enforcement agencies do not ‘target’ ivory as they do drugs or weapons, and technological advances, such as drug scanners and detection dogs, do not help with the interception of contraband ivory. Thus, the above 23,461kg should correspond to 234,610kg of smuggled ivory from about 23,000 elephants killed this past year.”

Dr Wasser’s team used DNA analysis to trace the source of one of the largest shipments of ivory intercepted in recent years, a consignment of about 6.5 tonnes seized in Singapore in 2002. It contained 532 tusks, with an average weight of 11kg.

The shipment also included 42,120 ivory cylinders, known as hankos, which are used to make stamps bearing personal seals, and which carry great prestige in South Asia. The hankos alone were worth about $8.4 million.

The DNA signatures of 67 tusks showed that they had come from older elephants from the savannah of Zambia. The size of the shipment contradicts official claims that only 135 elephants have been killed illegally in Zambia over the past ten years.

The disclosures have already influenced policy in Zambia, but further action is needed, Dr Wasser said. “Subsequent to being informed of our findings, the Zambian Government replaced its director of wildlife and began imposing significantly harsher sentences for convicted ivory traffickers.

“However, one still has to wonder whether this will be enough. Virtually no one has been prosecuted in this case.”

Genetic tracking of the origin of ivory should allow conservationists to protect elephants better where they are most at risk from poaching, he said, though international support was also needed. Western financial support for enforcing the ivory trade ban was largely withdrawn in 1993.

“What is really needed is to combine this with a major reinfusion of law enforcement aid at the scale that coincided with the 1989 ivory ban,” Dr Wasser said. “The international community virtually stopped ivory poaching once, and it can stop it again. Elephants are majestic animals and are not trivial to the ecosystem. They are a keystone species and taking them out significantly alters the habitat.”

White gold

— The number of African elephants decreased from 1.3 million in 1979 to 600,000 in 1989, when an international convention banned the trade of ivory. The population now stands at about 500,000

— Countries worst hit by poaching include Zambia, the Democratic Republic of Congo and Sudan Last year about 15 tonnes of ivory were seized — 10 to 15 per cent of the total traded

— An elephant carries about 7kg of ivory in its tusks

— About 60 to 70 per cent of ivory goes to the Far East, where it is used to make name seals, tourist trinkets and carvings

Source: Born Free Foundation

Times Recommends

• UK regional accents thrive against the odds
• ‘Scarecrow’ wind farms put rare birds to flight
• What an anti-climax: G-spot is a myth