Green invasion: a foreign mussel has taken hold in Tampa Bay, threatening native species and...

In late 1999, Tampa Electric Co. sent divers into Tampa Bay to find out what was blocking saltwater from reaching its plant through underwater pipes. They discovered that thousands of emerald green mussels, not native to the area, had clogged the pipes, causing generators to shut down.

Researchers identified the mollusks as Asian green mussels, native to the Pacific and Indian oceans and a delicacy in Asia. Scientists suspect that thousands of mussel larvae arrived in the holds of cargo ships, the way many non-indigenous water species come here. Most such creatures don