Narrator: OYSTERS
ARE A VERSATILE SHELLFISH.
YOU CAN BAKE THEM,
BOIL THEM, SMOKE THEM,
OR EAT THEM RAW
RIGHT FROM THE SHELL.
OVER THE YEARS,
WILD OYSTER STOCKS HAVE DECLINED
DUE TO OVERFISHING
AND POLLUTION.
SO TODAY, 95% OF THE OYSTERS WE
CONSUME COME FROM OYSTER FARMS.
OYSTERS ARE FILTER FEEDERS,
MEANING THEY DRAW SEAWATER
OVER THEIR GILLS
TO TRAP AND EAT
THE PHYTOPLANKTON --
MICROSCOPIC AQUATIC ORGANISMS.
AN ADULT OYSTER CAN FILTER
MORE THAN FIVE QUARTS
OF SEAWATER PER HOUR.
OYSTER FARMS ARE LOCATED
IN OR BY THE SEA
BECAUSE THE OYSTERS NEED TO FEED
OFF SEAWATER TO SURVIVE.
THE HATCHERY KEEPS THE OYSTERS
IN UPWELLERS --
MESH-BOTTOM BUCKETS
SITTING IN SEAWATER.
OYSTERS CAN REPRODUCE
ONCE THEY'RE SIX MONTHS OLD.
HOWEVER, THE IDEAL BREEDING AGE
IS BETWEEN TWO AND 10 YEARS.
AT BREEDING TIME, WORKERS PUT
THE OYSTERS INTO BREEDING TRAYS,
OSCILLATING THE TEMPERATURE
BETWEEN 68° AND 86°
TO STIMULATE SPAWNING.
THE FEMALES SQUIRT OUT EGGS,
THE MALES SQUIRT OUT SEMEN,
AND 16 HOURS LATER, THE
FERTILIZED EGGS HATCH LARVAE.
RIGHT FROM BIRTH,
THE OYSTERS FEED
ON A BLEND OF THE PHYTOPLANKTON
THEY'D EAT IN THE WILD.
THE HATCHERY DILUTES
THIS PLANKTON MIX IN SEAWATER
AND PUMPS IT
TO THE OYSTER CONTAINERS.
MARINE BIOLOGISTS
MANAGE THE PONDS
IN WHICH THE HATCHERY
GROWS ITS PHYTOPLANKTON SUPPLY.
THE LARVAE ARE SO TINY,
YOU CAN'T SEE THEM IN THE WATER.
THEY'RE VISIBLE
ONLY UNDER A MICROSCOPE.
RIGHT FROM THE TIME THEY HATCH,
THEY ALREADY HAVE A SHELL
AND CAN SWIM.
BY ABOUT THE TWO-WEEK MARK,
THEY'VE GROWN
TO THE SIZE OF A SPECK,
ABOUT 1/64 OF AN INCH LONG.
HOWEVER, NOW THEY ACT LIKE
MINIATURE ADULTS AND STAY PUT.
THE HATCHERY KEEPS THEM IN
SUSPENSION IN CIRCULATING WATER
SO THEY HAVE AN AMPLE SUPPLY
OF FOOD AND OXYGEN.
AS THEY GROW,
THEY'RE TRANSFERRED
TO PROGRESSIVELY LARGER BOTTLES.
BY THE TIME
THEY'RE FOUR TO SIX WEEKS OLD,
THEY'RE READY
TO LEAVE THE HATCHERY
AND MOVE TO THE OYSTER FARM.
THE FARM FLOATS IN A HARBOR.
THE BABY OYSTERS ARRIVING ARE
A TINY FRACTION OF AN INCH LONG.
THEY GO INTO UPWELLERS.
PIPES CIRCULATE SEAWATER,
AND THE BABIES FILTER-FEED
ON THE NATURAL PHYTOPLANKTON.
OVER THE NEXT SIX WEEKS OR SO,
THEY QUADRUPLE IN SIZE TO ABOUT
2/10 OF AN INCH IN LENGTH.
WORKERS THEN PACK THEM
IN PLASTIC MESH BAGS,
STACK THE BAGS ON METAL RACKS,
AND SUSPEND THE RACKS
IN THE SEA.
THE OYSTERS LIVE LIKE THAT
FOR THREE MONTHS,
GETTING TRANSFERRED INTO
PROGRESSIVELY LARGER MESH BAGS
AS THEY GROW.
HALFWAY INTO IT,
THE OYSTERS ARE THIS BIG --
ABOUT 8/10 OF AN INCH LONG.
BY THE END OF THREE MONTHS,
THEY'RE DOUBLE THIS SIZE,
GROWN UP ENOUGH TO LEAVE HOME
AND VENTURE OUT
INTO THE REAL WORLD.
WORKERS LAY THEM
ON THE SEA FLOOR
AND LEAVE THEM FOR SIX MONTHS
TO REACH HARVEST SIZE,
WHICH IS DETERMINED
NOT BY LENGTH ANYMORE,
BUT BY WEIGHT --
JUST UNDER THREE OUNCES.
TO FINALLY HARVEST THE OYSTERS,
THEY LOWER
A CUSTOM-BUILT MACHINE
THAT'S PART DREDGER,
PART CONVEYER.
IT GENERATES JETS OF WATER
THAT BLOW THE OYSTERS OFF
THE SEA BED ONTO THE CONVEYER.
THEY TRAVEL UP
OUT OF THE WATER INTO THE BOAT.
THAT CONVEYER DUMPS THE OYSTERS
ONTO ANOTHER CONVEYER
THAT LEADS
TO THE PICKING STATION.
THERE, WORKERS SELECT
THE CORRECT SIZE OYSTERS
AND PUT THEM INTO BASKETS.
WHATEVER
THEY LEAVE ON THE CONVEYER --
SMALLER OYSTERS, ROCKS,
AND SUCH --
CONTINUES TO THE END
AND DROPS BACK INTO THE WATER.
OF COURSE,
THE HARVESTING MACHINE MISSES
SOME THREE-OUNCE OYSTERS.
THOSE REMAIN ON THE SEABED
SOMETIMES FOR YEARS,
GROWING LARGER LIKE THIS GUY,
WEIGHING ABOUT 2.2 POUNDS.
PRIOR TO SALE,
THE HARVESTED OYSTERS
GO THROUGH A CLEANING PROCESS
CALLED DEPURATION.
FOR 42 HOURS, THEY SIT IN TANKS
FILLED WITH SEAWATER
STERILIZED BY ULTRAVIOLET LIGHT.
THE OYSTERS DRAW THIS
CLEAN WATER THROUGH THEIR GILLS.
THIS FLUSHES OUT
ALL THE BACTERIA.
THANKS TO
THIS DEPURATION PROCESS,
IT'S SAFE TO EAT RAW OYSTERS.
IT'S TAKEN A GOOD 18 MONTHS
TO GROW FROM MICROSCOPIC
ORGANISM TO DINING DELICACY,
WHICH HAS A REFRIGERATED
SHELF LIFE OF ABOUT A WEEK.
