When law enforcement agents tore open 50 boxes labeled T-shirts, jeans, tools, and auto parts last fall in Cincinnati, they found 3,700 live crabs with hairy claws and a deadly reputation.

The crabs were being imported by Asian markets and food suppliers to be sold in cities in the United States. The mitten crab, a Chinese delicacy also known as Shanghai hairy crab, is one of the world’s top hundred most invasive species that threaten native wildlife and habitats, making it a major target for officials fighting wildlife crime.

With ravenous appetites, mitten crabs prey on local wildlife, simultaneously upending food chains and fisheries. When they tunnel into the soft mud along riverbanks, they trigger erosion and destabilize levees.