IV EEPORT TO THE SECEETAEY OF COMMERCE 



to prevent fish from entering canals, mill races, and irrigation 

 ditches. The losses are heaviest in Pacific coast streams, where the 

 young salmon on their seaward migration find their way by the 

 millions into these diversion channels and finalh^ perish or are 

 destroyed. 



A survej' along the Yakima River, Wash., in 1916 revealed 20 fish 

 per acre on a 200-acre tract, or about 4,000 fish, of which 90 per 

 cent were migrating salmon. As this condition ma}' be multiplied 

 many times during a season, the economic waste of young food fishes 

 (salmon and trout) is very large. With respect to the Columbia 

 River area, the bureau has stated previousl}^ that large numbers 

 of young salmon on their seaward migration become lost in the 

 irrigation ditches or impounded in the pools left in the main stream 

 as the water is drawn off for irrigation, where the}" die as the water 

 warms and evaporates. From 80,000,000 to 90.000.000 salmon fry 

 are released in the Columbia River annually, while the annual catch 

 of adult fish is about 3,000.000. It has been estimated that 90 per cent 

 of the young salmon migrating seaward are lost in irrigation ditches, 



AVhile the States have laws requiring screening, the question is so 

 involved that strict compliance therewith has not been required. 

 The failure of screens to function satisfactorily and the number of 

 areas under Federal control have increased the difficulties. An act 

 of Congress, approved May 1, 1928, authorized an appropriation of 

 $25,000 " to study, investigate, and determine the best means and 

 methods of preventing the destruction of fish occasioned by ditches, 

 canals, and other works constructed or maintained bv the United 

 States'" 



PASSAMAQTJODDY POWER PROJECT 



Passamaquoddy Bay, including the estuar}^ of the St. Croix River, 

 covers about 100 square miles and is subject to a rise and fall of from 

 20 to 25 feet every 12 hours. Every 6 hours about 2,000,000,000 tons 

 of water boil through the narrow passages at the mouth of the ba3\ 

 According to Dr. A. G. Huntsman of the Biological Board of Canada, 

 who made a careful study of the proposed damming of the mouths 

 of Passamaquoddy and Cobscook Baj^s, at the entrance to the Bay of 

 Fundy, for power purposes, the construction of dams will have a 

 widespread and pronounced effect on the fisheries throughout the 

 region. The production of fish food in the region generally will be 

 reduced considerabl}^ and the fisheries for sardines, clams, cod, and 

 haddock of Passamaquoddy Bay may be wiped out, as well as the 

 sardine and pollock fisheries of the neighboring coast. 



SALMON INVESTIGATIVE WORK UNDER NEW HEAD 



The success of the bureau's salmon investigative program on the 

 Pacific coast is due in large measure to the highly practical researches 

 and intelligent directive effort of Dr. C. H. Gilbert, which won the 

 confidence of scientists, administrators, canners, and fishermen alike. 

 The tracing of the age and growth of salmons by studies of the con- 

 centric rings on their scales, and the determination of their migration 

 routes to spawning areas by tagging, marking, etc., have contributed 

 much needed information regarding the habits of these fishes, which 



