From restaurants to reefs: recycling discarded oyster shells

This Nov. 17, 2016 photo provided by the Coalition To Restore Coastal Louisiana shows large piles of shell being stored in Buras, La., which were collected for an oyster shell recycling program. The program spearheaded by two environmental groups in coordination with area restaurants aims to take a waste product that used to fill landfills and instead make it into a structure that tiny oyster larvae can latch onto and grow. The structures in turn can slow erosion and storm surge that is swiftly eating into Louisiana's coast as well as provide other environmental benefits. (Sarah Pate/Coalition To Restore Coastal Louisiana via AP) (The Associated Press)

In a Friday, Nov. 18, 2016 photo, Richie Blink, left, of the National Wildlife Federation, and Ben LeBlanc, president of LeBlanc Marine Construction, look over a map of the area where a reef was constructed from recycled oyster shells in St. Bernard Parish, La. The oyster shell recycling program spearheaded by two environmental groups in coordination with area restaurants aims to take a waste product that used to fill landfills and instead make it into a structure that tiny oyster larvae can latch onto and grow. The structures in turn can slow erosion and storm surge that is swiftly eating into Louisiana's coast as well as provide other environmental benefits. (AP Photo/Janet McConnaughey) (The Associated Press)

This Nov. 16, 2016 photo provided by the Coalition To Restore Coastal Louisiana shows gabion baskets filled with recycled oyster shells in Buras, La., before being loaded onto a barge for reef construction. The oyster shell recycling program spearheaded by two environmental groups in coordination with area restaurants aims to take a waste product that used to fill landfills and instead make it into a structure that tiny oyster larvae can latch onto and grow. The structures in turn can slow erosion and storm surge that is swiftly eating into Louisiana's coast as well as provide other environmental benefits. (Nic Dixon/Coalition To Restore Coastal Louisiana via AP) (The Associated Press)

If you slurp oysters from the half-shell in New Orleans, you may be doing more than satisfying a culinary craving: You could be helping to construct reefs that environmental groups hope will save a bit of Louisiana's coastline.

Since 2014, restaurants have contributed nearly 2,600 tons of shells to the Coalition to Restore Coastal Louisiana and The Nature Conservancy. About one-quarter of those shells now form a half-mile-long reef about 40 miles from New Orleans.

Tiny oyster larvae prefer to cement themselves to oyster shells as their permanent home. But for thousands of years, people have been eating oysters and tossing the shells.

Although Louisiana's oyster fishery is the nation's largest, until recently the state built shallow-water reefs mostly of concrete or limestone. Oyster-shell recycling was inspired by programs in other states, including Texas.