ZOOLOGY AND HUMAN \VELFARE 



warehouses, greenhouses, and trees covered with canvas; 

 and the most recent advances in communication systems 

 and automotive invention are employed. When crop 

 production is increased by these means, human wealth is 

 increased; and if the resultant fall in prices works hardship 

 on the producers, we need not hold that thereby the work 

 of economic zoology is rendered vain. Rather should econ- 

 omists be stimulated to find and cure the weaknesses of a 

 social system that permits the increased production of 

 wealth to work hardship on a large and absolutely essential 

 group of the population. 



We may now glance more briefly at some other branches 

 of economic zoology, in which, likewise, the work is 

 carried on in the belief that the conservation and improve- 

 ment of animal life as a source of wealth is, in itself, 

 justifiable, regardless of economic fallacies in the fields of 

 distribution and finance. The ocean is a potentially in- 

 exhaustible source of wealth because of the vast numbers 

 of food animals it can support with a minumum of human 

 cultivation. Fishes, mollusks, crustaceans, and echinoderms 

 swarm in it almost infinitely. Almost, but not quite. The 

 Bureau of Fisheries owes its existence largely to the fact 

 that oysters, lobsters, and certain valued food fishes have 

 become greatly reduced in numbers (in accessible areas) 

 through excessive catches, wasteful methods of handling, 

 destruction at the breeding season, injury by the waste of 

 large cities, and other preventable factors. It is clear that 

 the problems indicated here involve scientific studies on 

 habits, distribution, life histories, etc., to provide a 

 reliable basis for practical laws and recommendations. 

 Oceanic expeditions, requiring large expenditures of money 

 and months or years of service by specialists, are carried 

 out to determine the distribution and breeding places of 

 various species; and government vessels patrol the coasts 

 and survey nearby waters in minute detail. Other agencies 



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