The United States, in a conservation victory Friday, won the approval of an international wildlife summit for stronger protections for endangered freshwater tortoises and turtles, including Maryland's iconic diamondback terrapin.

Working with China and Vietnam, the U.S. delegation persuaded international wildlife officials to protect 47 species of tortoises and turtles in Asia and the United States by banning the commercial trade of some and placing quotas on the sale of others.

More than half the world's freshwater tortoises and turtles face extinction, yet they are hunted for food, pets and trinkets made from their shells, mostly in Asia. Turtles are also killed by urban sprawl, boats and crab traps, particularly in Texas and Maryland.

The adoption of one of the White House's top priorities at the summit in Bangkok — the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) — came on the heels of the defeat of a proposal to increase protections for polar bears.

The new protections for Asian turtles all but ensure that traders will now target freshwater turtles in the United States. To head that off, the United States proposed to list three native species: the spotted turtle, Blanding's turtles and the diamondback terrapin, the University of Maryland's mascot. CITES puts the three species in the category that allows commercial trade, but with a strict limit to protect them from being overharvested.