382 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1950 



phone communication, quick-freezing, radar, and other technological 

 advances? But the extent of exploitation will depend on economic, 

 marketing, and other factors, and it is not likely that these expansions 

 will raise the world's fisheries' production by two or three times within 

 the next decade. 



Curiously enough, the development of an ancient practice, fish farm- 

 ing, holds greatest promise for supplying protein in areas where it is 

 most needed and where nutrition is notably below minimal standards. 

 This sort of fish culture, involving the construction of special ponds 

 (either fresh-water or salt) in which all the operations of animal 

 husbandry are practiced, has existed for centuries in China and India, 

 as Hickling relates in Nature, for May 15, 1948. The ponds are shal- 

 low, roughly 3 to 5 feet in depth, and range in size from less than 

 an acre to 15 acres or more. Frequently they are used for agricultural 

 as well as fish crops — rice, water chestnut, watercress, and arrowhead 

 for human consumption ; water lilies and water hyacinth for pig food. 

 These plant and animal crops may alternate — paddy from February 

 to June and fish from July to January — or they may be simultaneous. 

 The ponds are often operated concurrently with vegetable gardens 

 and the raising of pigs and ducks ; they are fertilized both naturally 

 and by the application of farmyard manure and compost, resulting 

 in rich growths of plankton and hence tremendous production at the 

 lower levels of the food chain. As Hickling points out, these fish 

 ponds fit in well with a system of peasant small-holding. In some 

 localities the production of fish runs as high as 4,000 pounds per acre 

 annually; contrast that figure with the annual production of 50 

 pounds per acre from the sea bottom referred to earlier. 



The significance of fish farming is by no means as widely under- 

 stood as it should be. Although the farming of milkfish, carp, mullet, 

 gourami, tilapia, and other species calls for special knowledge, some- 

 times involving immensely skillful techniques, there is no reason why 

 it should not be practiced more widely and introduced into other areas 

 where it could be developed on a high scale. Production is cheap and 

 yields are high; many areas where human nutrition levels are low are 

 suitable for fish farming (protein shortage is the bane of many tropi- 

 cal populations), and with modern means of transportation the intro- 

 duction of foreign species is now possible as never before. 



Fish farming can be expected to boost the world's production of fish 

 in considerable amounts and to relieve dietary deficiencies in critical 

 areas to no small degree. Expansion of this time-honored practice 

 may yield more than all the atomic nets, electric fishing, electronic 

 aids, and other technological advances put together. This is not to 

 imply that fertilization of large tracts of the ocean by human agencies 

 holds any promise. During the war experiments in Scottish lochs 

 produced greatly increased growth rates in flatfish. Widespread and 



