Wildlife advocates and scientists are concerned that a proposed sale of elephant tusks may spur even more poaching of the animals in Africa. International trade in ivory is banned by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), but Tanzania and Zambia have asked the convention for a special sale of 112 tons of ivory.

Such a sale "would be devastating," especially because poaching is already on the rise, says zoologist Iain Douglas-Hamilton of Save the Elephants in Nairobi. "It would risk a further escalation of demand." However, the connection of one-time ivory sales to increased poaching has not been conclusively demonstrated, says David Morgan, the chief scientist for CITES in Geneva, Switzerland. The proposals will be considered when representatives from 175 nations meet 13 to 25 March in Qatar.

The current trade ban was put in place in 1989, after massive losses of elephants during the 1970s and '80s. In East Africa, poachers reduced populations by 50% to 80% and probably by even more in Central Africa. The ban worked: After 1989, populations in East Africa began to recover. Meanwhile, other countries, such as South Africa, had been amassing stockpiles of ivory collected from elephants that died naturally or nuisance animals that had been killed, and they wanted to sell the ivory and use the proceeds for conservation.

In 1997, CITES allowed three countries—Namibia, Botswana, and Zimbabwe—to sell a total of 50 tons of ivory. Because of fears that the sale would stimulate demand for ivory and encourage poachers, CITES created monitoring networks to keep tabs on illegal killings of elephants and seizures of ivory. These official studies indicated that poaching had declined in the years after the sale.

After getting permission in 2002, these three countries and South Africa sold another 106 tons of ivory. As part of that agreement, CITES put a 9-year moratorium on further sales (Science, 22 June 2007, p. 1678). But a loophole was added at the last minute: The moratorium would apply only to countries that had previously sold ivory.

That left the way open for other nations. Last November, Tanzania asked CITES for permission to sell 90 tons of ivory, and Zambia asked to sell 22 tons, all from natural deaths and culling. The two countries argue that the ivory trade is "essential to the conservation of elephants," because it will help resolve the growing conflicts between humans and elephants in their countries. "Elephant products such as ivory picked up from the wildlife-management areas could increase the value of elephants to those communities," the delegations claim.

Opponents, including international animal-welfare groups, scientists, and a coalition of 23 African countries, say the proposal violates the intent of the 2007 agreement. Further, CITES requires adequate law enforcement to prevent poaching and to stop illegal trade before a sale can be allowed. According to the monitoring networks, people in both Tanzania and Zambia are still "heavily involved" in the movement of large shipments of illegal ivory.

The main concern is that a legal sale would stimulate demand for ivory and create a parallel illegal trade, particularly in China, where a growing middle class sees ivory as a symbol of prosperity. "It is a virtually insatiable demand that elephants cannot satisfy," says Will Travers of Born Free, an advocacy group in Horsham, U.K.

There is no definitive proof of that connection from the official monitoring networks, however. "The results show that any link between the ivory sales that have taken place and levels of elephant poaching remains tenuous at best," says Morgan. Daniel Stiles, an expert on wildlife trade based in Diani Beach, Kenya, who has interviewed dozens of ivory traders, is skeptical that such sales increase demand. In the April 2005 issue of Environmental Conservation, he reported no sign of increased demand after the 1997 sale.

Other scientists counter that the monitoring networks aren't quick or complete enough to show the link between ivory sales and poaching. Patrick Omondi of the Kenya Wildlife Service criticizes the analysis of one network, Monitoring Illegal Killing of Elephants (MIKE), and says that in Kenya they have seen greater poaching, which they attribute to previous sales. The MIKE data are "not up to speed with the reality on the ground," he says. Travers agrees that MIKE's data are so patchy that they should not be the basis for deciding whether the sale goes forward.

Everyone agrees, however, that poaching is now on the rise. The number of illegally killed elephants found has increased from 47 to 232 over the past 3 years in Kenya, a country with relatively good management and enforcement. TRAFFIC, a network run by the WWF and IUCN, says that CITES needs to focus on improving enforcement in the three countries "most heavily implicated" in the ivory trade, the Democratic Republic of the Congo, Nigeria, and Thailand.

Momentum appears to be building against the proposed sales. The United Kingdom announced last week that it is opposed. And the coalition of 23 African countries sent representatives to Brussels last week to lobby the European Union. The coalition has its own proposal for CITES: a 20-year moratorium on ivory sales in order to put better controls in place and to study the impact of legal sales.