The 175-nation Convention on International Trade in Endangered Species (CITES) first rejected the Tanzania proposal for a one-off sale of existing ivory stocks and then swept aside a Zambian compromise to allow for future sales of tusks.
The rulings were a rare victory for environmentalists at the two-week meeting where they have endured defeats of proposals ranging from an export ban on Atlantic bluefin tuna to a shark conservation plan to a measure to regulate trade of red and pink corals.
The proposals would have been the third and fourth such one-time ivory sales following cases in 1999 and 2008.
Prof. Samuel K. Wasser, director of the Center for Conservation Biology at the University of Washington, said there is a clear link between one-off sales and the rise in poaching. He said the sales revive dormant markets by sending consumers the message that it is OK in general to once again buy ivory and makes it difficult to differentiate between legal and illegal products.
"This is a rare victory for elephants," said Jason Bell-Leask, director of the International Fund for Animal Welfare, Southern Africa.
Tanzania was asking to sell almost 200,000 pounds of ivory that would have generated as much as $20 million. It noted in its proposal that its elephant population has risen from about 55,000 in 1989 to almost 137,000, according to a 2007 study.
Zambia wanted to sell 48,000 pounds of ivory. It withdrew a request for the ivory sale and offered a compromise to allow a regulated trade in elephants parts excluding ivory - a first step toward future tusk sales.
It picked up support from the United States and some European nations, but the proposal was defeated mostly due to opposition from the 23-nation, African Elephant Coalition.
The two countries argued that its elephant population had reached the point where they were trampling crops and killing too many people. They also said preventing them from selling the stocks which come from natural deaths or controlled culling of problem animals - would increase anger toward the beasts who are seen increasingly as pests by affected communities.
"Tanzania is committed to conservation of its wildlife including elephants," said Shamsa Selengia Mwangunga, the country's minister of natural resources and tourism. "But should this meeting fail to consider this proposal, we run the risk of enhancing hostility against elephants by our local community especially where human-elephant conflicts are prevalent. More elephants would be killed."
Zambia's Minister of Tourism, Environment and Natural Resources Catherine Namugala accused activists and other delegates of misrepresenting the poaching situation in her country and spreading rumors that it would spend the money raised from sales on election campaigns.
It also complained that her country was struggling to protect elephants when it couldn't provide its citizens with basic needs.
"We can't justify failure to take a child to school because we are using resources to conserve elephants," Namugala said. "I appeal to allow Zambia to utilize the natural resources given to us by God."
But several central and west African countries say the two nations have not done enough to combat poaching and slow the illegal trade in ivory. They also wanted more time to assess whether a 2008 ivory sale by Zimbabwe, Botswana, South Africa, Namibia had contributed to the illegal trade.
Ivory sales have in recent years been among the most contentious proposals at CITES and this time around African countries, and even some environmental groups, are divided. The ivory would be sold to China and Japan - the only countries which have asked to purchase it.
TRAFFIC, the wildlife trade monitoring group, tracks ivory seizures and found that poaching and smuggling to markets mostly in Asia has risen steadily since 2004. They blame weak law enforcement in Africa and growing demand for ivory products like chopsticks and ivory jewelry mostly in China, Thailand and other Asian countries.
The price of ivory on the black market has risen from about $200-a-kilo in 2004 to as much as $1,500 now.
Africa elephants have seen their numbers drop in the past 40 years by more than to 600,000 mostly due to poaching. A global ban on the ivory trade in 1989 briefly halted their slide. But conservationists said that poaching, especially in central Africa, now leads to the loss of as many as 60,000 elephants each year. Without intervention, the elephants could be nearly extinct by 2020.