30 AETIFICIAL PROPAGATION OF PACIFIC SALMONS. 



One of the first cheap foods to be utilized in large quantities by the 

 Bureau of Fisheries was the Columbia Kiver smelt, which was first 

 tried at the Oregon stations about five years ago. These fish can be 

 purchased during the run at the height of the season for $20 per ton 

 at a cold-storage plant in Portland, Oreg. An additional charge of 

 $20 per ton covers sharp freezing and storing for a period of six 

 months, and this, together with transportation charges, makes the 

 average cost of the fish about 2^ cents a pound delivered. 



Smelt have been fed both raw and cooked. When used in the 

 raw state the fins and heads are removed, and the fish are ground once 

 through the coarse plate of an Enterprise meat chopper, after which 

 they are run through the fine plate twice. However, this method has 

 not proved very satisfactory, as smelt are very oily, and, in feeding, 

 difficulty has been experienced in keeping the troughs clean. Intes- 

 tinal trouble is also feared from the innumerable small, sharp bones. 



The method which has given most satisfactory results is to place 

 the smelt in 50 or 100 pound lots in a farm kettle and cook them 

 until the bones become softened. After this a quantity of the 

 cooked mass convenient for handling is placed in gunny sacks and 

 permitted to drain thoroughly. The mass in the sack is then trans- 

 ferred to a press of convenient size, operated by an ordinary house 

 jack, and is pressed into cakes 12 inches square and varying from 3^ 

 to 4 inches in thickness. The burlap forming the sack is peeled 

 aw^ay and is serviceable for further use. Quantities of this food can 

 be prepared at one time, and, if kept in a cool, dry place, will remain 

 in a wholesome condition for several days. When needed for food 

 it is grated by means of a homemade power grater and screen, the 

 degree of fineness depending upon the age of the fish to be fed. 

 After this operation it presents the appearance of coarse meal. It 

 can be scattered over the surface of the water and is cleaned up by 

 the fish before it reaches the bottom. Prepared in this manner it 

 makes a good, clean, rich food, and the fish take it readily. Its cost 

 is also very moderate. 



Beef and hog melts have been successfully used in conjunction with 

 mush, both for the purpose of varying the diet, and with the view of 

 eliminating the use of liver in large amounts after the fish are a few 

 weeks old. The cost of this material will average about 3 cents per 

 pound. 



Culled canned salmon, or " do overs," have also been employed to 

 good advantage in the feeding of young salmon. The contents of 

 the cans are first thoroughly heated and then pressed and grated 

 in the manner described above in the preparation of smelt. Par- 

 ticular attention is invited to this method of using canned salmon 

 as fish food in view of the fact that considerable complaint has been 

 made as to the results of its use in the past. If prepared in the 

 manner specified, the material is certain to give satisfactory results. 



After several years' success in the feeding of canned salmon it 

 occurred to representatives of the Bureau that the fish used in a 

 spawning operation, if properly preserved and prepared, would 

 make a good and inexpensive food. Instructions were accordingly 

 issued to all the west coast superintendents, including those in 

 Alaska, to put up a quantity of the spawned salmon, and it is ex- 

 tensively used at those stations at the present time. After being 

 relieved of their eggs the fish are skinned, split, and carefully boned. 



