Oyster bed restoration

Volunteers help lay bags of oyster shells in Alabama's Mobile Bay as part of a project by The Nature Conservancy and other environmental groups to restore oyster reefs in the Gulf of Mexico, in Mobile, Alabama.

Volunteers from across America are rebuilding oyster reefs along the Gulf of Mexico's delicate shoreline, hoping to revive oyster beds under assault for decades from overharvesting, coastal development, pollution, and most recently the BP oil spill.

The waters harbour much of the world's last remaining productive natural oyster beds, but BP PLC's April 20 oil well blowout dumped millions of gallons of crude into the Gulf and dealt yet another blow to the once bountiful habitat.

This past weekend, volunteers descended on Mobile Bay, Alabama, with 23,000 bags of oyster shells aimed at eventually creating 100 miles (160 km) of new oyster reefs near the shoreline. The goal is to help replenish oyster reefs that promote new growth, help protect delicate salt marshes and sea grasses, and act like coral in the tropics to provide habitat for numerous marine species.

It's one of the first coastal restoration projects since the oil spill sent thick crude washing into estuaries and onto beaches.

Biologist Rob Brumbaugh of The Nature Conservancy, which helped organise the event, said studies show that the world has already lost 85 per cent of its natural oyster reefs, but the Gulf of Mexico remains a bright spot, even after the oil spill.

About 350 volunteers came to lay 10-pound (4.5 kg) bags of oyster shells in a neat line several feet high on mud flats about 150 feet (45 m) offshore to create new reefs across Mobile Bay.

Funding

The U.S. Fish and Wildlife Service contributed about $70,000 to the project, which was approved before the oil spill but was delayed until the waters were relatively clear of crude. Funding also came from the National Oceanic and Atmospheric Administration and donations.

The total cost is expected to be about $100 million, and it likely will take up to five years to complete if funding continues. Brumbaugh said the oysters also help keep waterways clean. Each oyster can filter up to 50 gallons (190 litres) of water a day.

Oysters along the entire Gulf Coast were hit hard in the spill's aftermath, prompting closures and delays of harvesting seasons that are part of the region's economic lifeblood.

As much as 65 per cent of the nation's oysters come from the Gulf.