IS IRRIGATION DETRIMENTAL TO TROUT 

 CULTURE? 



By W. T. Thompson 



The question of the relation of irrigation to trout cul- 

 ture is necessarily one of comparatively recent date, though 

 irrigation itself is as old as civilization. In the new world, 

 it successfully encountered unique irrigational problems on 

 the high plains of the great west, where the growth of irri- 

 gation in recent years has been phenomenal. Few realize 

 even in a small measure how much it has done for this sec- 

 tion of our country. Our "Great American Desert" is 

 being rapidly irrigated out of existence. Where it once 

 stood, we now find prosperous agricultural communities, 

 supporting thriving" towns and cities. 



As public spirited citizens we cannot but take pride in 

 these material evidences of progress. As fish culturists, 

 however, and as members of this American Fisheries So- 

 ciety, should we not consider whether in this wholesale 

 diversion of large quantities of water for irrigation, there 

 exists no menace to the cause of fish culture; if such would 

 appear to be the case, whether these unfavorable conditions 

 are permanent and enduring or whether they are suscep- 

 tible of modifications; and finally, whether in the evolution 

 of the science of irrigation from its cruder forms to its more 

 finished state there may not arise some new factor which 

 will bring about a readjustment of conditions on a more 

 favorable basis ? 



Our early irrigation, like that of the ancients, was largely 

 basin irrigation, dependent on floods; available only for a 

 limited time and covering but a restricted area. It was the 

 creation of the more or less primitive conditions then exist- 

 ing. The pioneer settled in the valleys, where by a minimum 

 amount of labor and expense he could irrigate a sufficient 

 area of land to provide food for the family and a limited 

 provender for the family cow and work horses. Other set- 



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