Volunteers at Mississippi’s coast raise oyster gardens to restore reefs

Students of St. Stanislaus High School on Mississippi’s Gulf coast are on a mission to revive the reefs.

Students, standing on a platform beneath the school’s long pier, gently shake their oyster garden’s wire cages as they remove them out of the sea, clearing silt and algae that may be preventing water and nutrients from reaching baby oysters clinging to those shells.

These students are part of a volunteer team that is rearing oysters from translucent spat, with a width of a soda straw to hard-shelled bivalves that can help restore degraded reefs along the coasts.

Coastal ecosystems rely heavily on oyster reefs. Each oyster filters 25 to 50 gallons of water each day (95 to 190 litres). Spat attach to larger oysters and grow there. The reefs safeguard shorelines while providing habitat for shrimp, crabs and fish.
There are over 1,000 oyster gardens in Maryland, Virginia, Mississippi and Alabama alone, the majority of which are housed in wire cages suspended from private docks or open-topped floats linked to them.

Dennis Hatfield of Gulf Shores, Alabama, said that the quantity of crabs, fish, shrimp, sponges and other species that he removes from his cages on Little Lagoon each summer, astounds him.

‘I’m confident we’re establishing habitat in the lagoon,’ he added, noting that many of the 50,000 to 55,000 adult oysters cultivated there each year end up on Mobile Bay reefs.

An average of 37,400 tonnes of oysters were harvested annually from brackish waterways across the United States in the 1950s.

Overharvesting, pollution, parasites, suffocating sediment and other issues caused oyster harvests to drop 68 percent to around 11,900 tonnes per year in the 1990s, according to federal data.

 

Oysters are grown near the surface by commercial growers all throughout the country because they mature quicker there because the water holds more of the plankton they feed and predators are easier to remove.