Reproduction 95 



In another year, the spawn of 100 pairs ot bass producing an average of 

 2000 eggs per female was subject to such heavy predation that the survival 

 rate was only 5 per cent. Thus, 



100 X .05 X 2000 = 10,000 fry produced. 



In these illustrations, twenty spawners in the first spawning season 

 would produce more 1-inch fry than would 200 spawners in the following 

 season. 



<: 



•73 



p; 

 :=! 

 o 



1953 



1955 



2 1 



Pond No. 



2 1 3 



Pond No. 



3 2 



Pond No. 



Stocking rate of adult cai-p 



Production of young 

 carp 



Survival of adult carp 



Figure 5.1. Production of carp in small ponds at Lake Mills, Wisconsin. 

 These experiments demonstrate that there is no consistent relationship be- 

 tween the number of adult fish stocked (pounds) and poundage of young carp 

 produced. The poundage of young brought forth by the smallest poundage of 

 adults usually equals or exceeds the poundage of young produced by larger 

 numbers of adults (pounds). Also, the total poundage of all carp produced 

 in individual ponds is not consistent from year to year. [From Mraz, D., and 

 Cooper, E. L., Jour. Wildlife Mangt., 21(1) (1957)] 



In comparing annual estimates of schoohng bass fry with the numbers 

 of sexually mature bass known to be present in Ridge Lake in each of 

 10 years (1941-1951), I was unable to show any correlation between 

 number of spawners and the fry produced other than an indication of a 

 negative relationship, e.g., in several years when the numbers of spawners 



