In the oy。sters were raised in much the same way as dirt farmers raised tomatoes- by transplanting them. First, farmers selected the oyster bed, cleared the bottom of old shells and other debris, then scattered clean shells about. Next, they "planted" fertilized oyster eggs, which within two or three weeks hatched into larvae. The larvae drifted u。ntil they attached themselves to the clean shells on the bottom. There they remained and in time grew into baby oysters called。 seed or spat. The spat grew larger by drawing in seawater from which they derived microscopic particles of food. Before long, farmers gathered the baby oysters, tr。ansplanted them onc。e more into another body of water to fatten them up.
Until recently the supply of wild oysters and those crudely farmed were more than enough to satisfy people's needs. But today the delectable seafood is no longer a。vailable in abundance. The problem has become so serious that some oyster beds have vanished entirely.
Fortunat。ely, as far back as the early 1900's marine biologists realized th。at if new measures were not taken, oysters would become extinc。t or at best a l。uxury food. So they set up well-equipped ha。tcheries and went to work. But they did not have the proper equipment or the skill to handle the eggs. They did not know when, what, and ho。w to feed the larvae. And they knew little about the predators that attack and eat baby oysters by the milli。ons. They failed, but they doggedly kept at it. Finally, in the 1940's a significant breakthrough was made.
T。he marine biologists discovered that by raising the temperature of the water, they could induce oysters to spawn not only in the summer but also in the fall, winter, and spring. Later they developed a technique for feeding the larvae and rearing th。em to spat. Going still further, they succeeded in breeding new strains that were resis。tant to diseases, grew faster and larger, and flouri。shed in water of different salinities and temperatures. In addition
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