PACIFIC SALMON FISHERIES. 211 



My experiments along this line lead me to express the opinion that by the burial 

 of freshly fertilized salmon eggs under 6 or 7 inches of sand and gravel strong healthy 

 fn- can be produced at less cost than under existing hatching methods, and that fry 

 so produced are stronger and more capable of resisting the attacks of their active 

 enemies. 



I trust that this short statement of my experiments in the burial of salmon eggs 

 may be deemed of sufficient economic importance to stimulate fish culturists generally 

 in experimenting along similar lines. Those ■who do Tdll perhaps experience some 

 difficulty at first in tbe covering of a large number of eggs. Experimenters will find 

 that after preparing suitable beds of sand and small gravel the eggs can be evenly laid 

 and held until covered, if the surface of the bed is first thickly indented yrith cells a 

 little deeper than the eggs. This can be readily accomplished by stamping the bed 

 vrith a board covered with projections or pegs of suitable size. 



My experiments suggest that in the near future most of the buildings and hatching 

 apparatus now used in the propagation of salmon and trout will be dispensed ^vith; 

 that after the eggs have been expressed and fertilized, instead of being placed in ^\'ire 

 baskets in hatcheries, they will oe buried beneath the sand and gravel of the beds of 

 natural or prepared streams, and that with the exception of watchmen to protect 

 them, little or no other labor will be required. 



FEEDING AND PLANTING THE FRY. 



For some time the fry remain at the bottom of the trough, but 

 when the yolk sac is nearly absorbed they rise from the bottom and 

 begin s\\ imming. As a rule the fry are planted about the time the 

 yolk sac is absorbed, thus obviating the necessity for feeding them. 

 Some experts advise planting young red salmon when the umbilical 

 sac is about two-thirds absorbed, which is the time when the fish 

 b<'gin to swim up freely. With the temperatures prevailing at the 

 Alaska hatcheries, this means that the fry must be held at least four 

 or five weeks after hatching. 



PACKING EGGS FOR SHIPMENT. 



In packing salmon eggs for shipment it is the custom at the l^ureau 

 of Fisheries' hatcheries to use a packing box made of one-half inch 

 pine, 2 feet square and 1 foot deep."* 



At the bottom is placed a thick layer of moss, then a layer of mosquito netting, then 

 a layer of eggs, then mosquito netting again, then successive layers of moss, netiinia;, 

 eggs, netting, and so on to the middle of the box. Here a firm wooden partition la 

 fastened in and the packing renewed above in the same manner as below. The cover 

 is then laid on the top, and when two boxes are ready they are placed in a wooden 

 crate, made large enough to allow a space of 3 inches on all sides of the boxes. This 

 space is filled -with hay to protect the eggs against changes of temperature, and, the 

 cover being put on the eggs, they are ready to ship. In the middle of the crate an 

 open space about 4 inches in depth is left, between the two boxes of oggs, for ice. 

 As soon as the crates arrive at the railway station this space, as well as the top of the 

 crate is filled in nith ice. Recent experiments show that salmon eggs can be packed 

 and safely transported to considerable distances when they are first taken. 



REARING SALMON FRY. 



For many years it was the custom to plant the fry as soon as they 

 harl absorbed, the yolk sac, a period of about 30 days. A few thou- 

 sands were sometimes raised to the fmgerling, yearling, or adult 

 stagi!, more as a curiosity than anything else. No particular difh- 

 culty was experienced in raising these fish, but the expense^ entailed 

 in feeding them for a ])rolonged period, and the im])ossioility of doing* 

 so unless large ponds were constructed at great expense for the pur- 



« A Manual of P'hh-ciiltiirc, Bo.«o<l on tlir Mothod.s ol the United States Commissiou of Fish and Fish- 

 erics, revised edition, p. 14. Washington, 1017. 



