The six smooth-coated otters (Lutrogale perspicillata)—Southeast Asia's largest otter—and five oriental small-clawed otters (Aonyx cinerea), the world's smallest otters at less than 11 pounds (five kilograms), are under threat in Southeast Asia.

Demand for their pelts and organs for clothing, food, and medicine—in addition to habitat destruction and environmental pollution—have diminished both populations. (Read an exposé of the world's most notorious wildlife dealer, from National Geographic magazine.)

But otters aren't the only victims of the illicit wildlife trade. Stuffed into carry-ons, packed into suitcases, and bundled into crates, traffickers have tried to smuggle all kinds of wild animals through airports.

"The U.S. seizes over $10 million worth of illegal wildlife each year, but this only scratches the surface," said Edward Grace,