Oyster gardeners restore US population of water-cleaning mollusks

For many just a tasty delicacy, the oyster may actually be the hero the world needs to fight environmental degradation -- and volunteers like Kimberly Price are battling to repopulate the surprisingly powerful species. The 53-year-old is an "oyster gardener" who fosters thousands of the mollusks at her waterside home until they are old enough to be planted in the Chesapeake Bay near the US capital Washington, where they clean the water and can even offset climate change.