FOOD SHORTAGES AND THE SEA MERRIMAN 375 



through the utilization of tidal energy, and by special processing this 

 nutritious material might be made quite acceptable as human food. 

 But the harvesting of a plankton crop would require the continuous 

 filtering of stupendous quantities of water and would demand such an 

 enormous output of energy that any large-scale process of this sort 

 is completely impractical — at least until atomic energy is turned to 

 constructive rather than destructive ends, and even then the problems 

 would be complex. Such harvesting still belongs in the realm of 

 fantasy ; to collect the plankton in water of average depth overlying 

 only an acre of fishing bottom would require the filtration of perhaps 

 50 million gallons of water through the finest sort of bolting cloth 

 many times over in the course of a year. As Riley puts it, "By and 

 large we must leave the plankton to the fishes." 



But though we must leave the plankton, are the fishes necessarily 

 the consumers to whom we must leave it? Are there perhaps, other 

 organisms that might be harvested at a more efficient level in the food 

 chain? Oysters, clams, mussels, and other molluscan species feed 

 directly on microscopic plankton ; hence there is less loss of organic 

 material than in the end product of a food chain which has involved 

 a number of steps. On this account production is relatively efficient. 

 But as a rule such animals are extremely slow-growing, and since 

 they live in the shallow part of the ocean and are sedentary, they are 

 readily accessible to man ; therefore natural populations are likely to 

 be fished out. 



For example, Connecticut oyster grounds showed a decline as early 

 as the eighteenth century, and by 1830 the supply had decreased to 

 such an extent that oysters from Chesapeake Bay were imported in 

 large quantities. In the second half of the nineteenth century the 

 highly specialized business of oyster culture developed in Long Island 

 Sound. Then the Chesapeake oyster began to show signs of serious 

 depletion, and by 1900 importation from the South had ceased. As 

 Gordon Sweet points out in the Geographical Review (October 1941), 

 oysters were now removed from the low-priced staple food class and 

 the price rose to such an extent that they became a luxury. 



Present-day oyster farming in Long Island Sound is a difficult and 

 skilled type of agriculture. Land under water is leased by an act 

 of the Connecticut legislature. The beds must be protected from 

 starfish, which open and feed on oysters by means still not fully un- 

 derstood, and from small snails which riddle the shells with holes, 

 and the oysters must be transplanted to different areas for optimal 

 growth at different stages of their life history. After preparing 

 clean beds of shells on which the baby free-swimming oyster larvae 

 settle and become "spat"' during the summer, the oyster farmer trans- 

 plants his growing crop at least three times in the next 4 years. 



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