198 FISH CULTURE 



fishes, is mucH slower, nature devoting herself 

 to giving the fish girth and weight rather than 

 length. 



Death is always busy among young fish 

 hatched in huge quantities from the eggs of a 

 single parent. Loss from other causes than 

 death is also great among minute fry, in the 

 majority of cases at least 90 per cent. This 

 would be appalling and discouraging, were not 

 the spawn furnished by the female yellow perch 

 almost limitless in amount. A string of 50,000 

 eggs will yield after aU losses about 5,000 fish 

 a year old, probably three times the yield in 

 nature. A single hatching-jar would hold in 

 the neighbourhood of 600,000 eggs, so that one 

 jar alone would yield about 60,000 yearlings. 



Owing to the great loss during the first few 

 weeks after hatching, it is necessary to stock 

 very heavily a pond intended for rearing pur- 

 poses. The amount of yellow-perch fry intro- 

 duced should be at least sixty or seventy times 

 the number of yearlings which it would com- 

 fortably carry. This is an important point be- 

 cause it is not necessary to do any sorting the 

 first year. Although a carnivorous fish, the 



