SALMON AND SEA-TROUT 



are not used, the bottom of the artificial bed 

 should be covered with clean gravel. 



The time which elapses from the impregnation 

 of the eggs to their hatching out varies accord- 

 ing to the temperature of the water, a fairly 

 average time is about ninety days. The ova 

 should be watched during this time, and the 

 dead ones removed. For a short time after they 

 are impregnated they are fairly hardy, but from 

 then till shortly before they hatch out the very 

 slightest concussion will kill or seriously injure 

 them. 



The management of sea-trout ova is similar to 

 that of salmon, and the ova are obtained in the 

 same way. As in the case of the salmon it is 

 best to rear the little fish artificially, till they 

 are ready to go down to the sea ; they will thus 

 escape dangers likely to cause the loss of about 

 eighty per cent, of their number. 



The same methods and the same precautions as 

 advised in the chapters on rearing trout should 

 be adopted in the case of salmon and sea-trout as 

 far as is possible, and if this is done a very large 

 percentage of the ova should be successfully 

 reared to the smolt stage. 



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