2. Students and staff from St. Stanislaus walking on pier
3. Oyster cage being pulled up from the water
4. Oyster shells being pulled from cage to inspect for baby oysters known as spat
5. Tight of oyster shells in cage
ANNOTATION: A Mississippi high school is home to one of more than 1,000 oyster gardens dotting the shorelines of at least six coastal states.
6. Student inspecting oyster shell
7. Student dipping oyster cage to remove sediment
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8. SOUNDBITE (English) Letha Boudreaux, St. Stanislaus High School:
"When they get out there, they have to dunk the baskets, try to get as much sediment off of them as possible, open the baskets up, check for predators, remove predators, look for spat that's still alive, measure the spat, record that data."
9. Tight of stone crab
10. Various of students measuring spat on oyster shells
ANNOTATION: Oyster reefs are a keystone of coastal ecosystems, with each oyster filtering some 25 to 30 gallons of water a day.
Volunteers along U.S. coasts are raising oysters from tiny translucent spat to hard-shelled bivalves that can help restore depleted reefs.
Oyster reefs are a keystone of coastal ecosystems, with each oyster filtering some 25 to 50 gallons of water a day.
Spat glue themselves to larger oysters and grow, and the reefs provide habitat for shrimp, crabs and many kinds of fish, and can also protect shorelines.
Just in Maryland, Virginia, Mississippi and Alabama there are more than 1,000 oyster gardens.
Most are in wire cages hanging from private docks or open-topped floats tied up like dinghies.
On the Mississippi Gulf Coast, students from St. Stanislaus High School tend to their cages from a pier, gently shaking their oyster garden's wire cages as they pull them from the water, loosening mud and algae that might keep water and nutrients from baby oysters clinging to those shells.
The program in Bay St. Louis is in its sixth year.
This year saw a high mortality rate due to low salinity levels, but typically the oysters only need 4 or 5 months to be big enough to transplant.
In the 1950s, an average of 37,400 tons of oysters were taken annually from brackish waters nationwide.
But overharvesting, pollution, parasites, smothering sediment and other problems saw U.S. oyster harvests fall 68% to about 11,900 tons a year in the 1990s, federal figures show.
Commercial farmers around the country grow oysters near the surface because they mature much faster where the water holds more of the plankton they eat and predators can be more easily removed.
Oyster gardening uses the same techniques on a smaller scale. But the oysters aren't being grown for the half-shell or deep fryer.
It's as much education as restoration.
Rayne Palmer, an Auburn University graduate student who runs the Mississippi-Alabama Sea Grant's gardening program in Mississippi, says at least two schools in Mississippi incorporate the gardens in their marine science curriculums.
Empty shells also go onto reefs, said Letha Boudreaux, head of the marine biology program at St. Stanislaus.
Oyster shells are the hard surface spat prefer, and entire artificial reefs are made from recycled shells.
Oyster gardening started in the late 1990s around the Chesapeake Bay, where harvests had plummeted 90% in two decades.
The Mississippi-Alabama Sea Grant's oyster gardening program, modeled on the Chesapeake's, started in Alabama in 2001 as master's thesis research.
The Chesapeake Bay oysters were beset by two highly lethal parasitic diseases, in addition to other problems.
Declines in the second half of the 1900s followed an even more drastic crash in the 1920s from rampant overharvesting.
Gardeners in the foundation and its member groups have added at least 15 million oysters in Maryland and 1 million in Virginia.
An umbrella group called the Chesapeake Oyster Alliance has set a goal of 10 billion added oysters by 2025.