REPORT OF COMMISSIONER OF FISH AND FISHERIES. LI 



are now takeu in salt or brackish waters, in which natural reproduction 

 can not be accomplished. 



Indeed, so small is the proportion of the seasonal runs of shad, which 

 succeed in making their way into and up our rivers and reaching their 

 spawning grounds, that natural reproduction has ceased to be a mate- 

 rial factor in influencing the conditions affecting our shad fisheries. 



The increased production of this fishery is to be attributed to the 

 fish-cultural work of the United States and State Fish Commissions. 

 The increased value of this fishery is a measure of the economic value 

 of this work to the people of the country. 



INTRODUCTION AND ACCLIMATION OF NEW SPECIES. 



Experiments in acclimation have always constituted an important 

 feature of the work of the Commission. 



These have been directed as well to extending the area of distribution 

 of our most valuable indigenous species as to the introduction from 

 other countries of species promising important additions to our economic 

 resources. 

 The Shad (Clupea sapidissima). 



The introduction of the shad into the waters of the Pacific coast, 

 and its multiplication there so as to become an important acquisition to 

 the food resources of that region, is a remarkable illustration of the 

 valuable results to be expected from well directed efforts in accli- 

 mation. 



Several plants were made in the Sacramento Kiver at Tehama, as 

 follows : 



Inl871 12,000 



Inl873 , 35,000 



- In 1876 99,000 



In 1878 150,000 



In 1880 250,000 



From these slender colonies, aggregating less than 1 per cent, of the 

 number now annually planted on our Atlantic slope rivers, the shad 

 have multiplied and distributed themselves along 2,000 miles of coast 

 from the Golden Gate of California to Vancouver Island in British Co- 

 lumbia. They are abundant in some of the rivers, common in most of 

 them, and occasional ones may be found everywhere in the estuaries 

 and bays of this long coast line. 



Prior to our experiments on the west coast it was a dictum of fish 

 culture that fish planted in a river would return to it when mature for 

 the purpose of spawning. The result of these experiments has been to 

 demonstrate that this instinct of nativity, should it really exist, is in 

 this case dominated by other influences, which have dispersed the shad 

 planted in the Sacramento widely beyond the limits which we had as-' 

 sigued to them, and in the most unexpected direction. 



The cause is probably to be sought in the genial influences of the 



