WASHINGTON –

It was a professional hit, the quick and ruthless slaying of a family of 12. Poachers with machetes hacked off the tusks of 11 African elephants on Jan. 5 in a Kenyan reserve, passing over a baby that was crushed by its mother after a gunshot felled her.

The same day, customs officials in Hong Kong seized more than 770 tusks, weighing more than a ton and valued at over $1 million, according to Born Free USA, a group that tracks poaching and government seizures.

The United Nations banned the ivory trade in 1989 but created exceptions that allowed African nations with stockpiles of seized ivory, or ivory removed from beasts that died naturally, to sell it legally. That gave poachers and crime syndicates an opportunity to sneak illegal ivory into the legal stockpile through a back door, critics said. Ivory can fetch about $1,000 per pound (0.45 kg).

The highest amount of illegal ivory on the world market in the decade the trade has been tracked was about 40 tons, in 2011.

Elephants and their ivory are expected to grab a large share of the spotlight at the March conference in Bangkok of the Convention on International Trade in Endangered Species of Wild Fauna and Flora. And Thailand will be a major focus. "Thailand has been an issue for a number of years," said Leigh Henry, senior policy adviser for species conservation at the World Wildlife Fund.

At issue is not so much that Thailand allows domestic ivory from captive Asian elephants to be sold, providing material for the country's traditional carvers. It is that the WWF and other global groups believe Thailand's legal trade gives cover to an illegal trade in ivory from wild African elephants. The WWF launched a petition this week to pressure Thailand to ban its legal domestic trade of elephant ivory, and made note of the January slaughter in Kenya, the worst in the nation's 30 years of record keeping.

Thai lawmakers have tried unsuccessfully to tighten rules on the domestic trade, and conservationists now say they are fed up. They plan to ask European and U.S. delegates from agencies such as the State Department and Fish and Wildlife Service to recommend a suspension of trade that would cut off Thailand from a lucrative trade in reptiles, birds and flowers, as well as animal skins, if the country fails to act right away.

Thailand is second only to China in the trade of meticulously carved ivory ornaments, supporting the poaching boom, conservationists argue. Thai authorities "will now have their feet held to the fire," Henry said.

That is easier said than done. At the convention's 16th Conference of the Parties in Thailand, where delegates will review the multibillion-dollar trade of wildlife and debate whether to impose regulations for the conservation of certain animals and plant life, some are expected to lobby fiercely against new regulations on everything from sharks to orchids.