232 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



O 

 U) 



a. 



O 

 O 



X 



$ 

 o 

 c 

 o 



in 



z 

 o 

 n 



< 

 u 

 w 



Ik 

 o 



bl 

 O 



< 

 h- 

 Z 

 bJ 



u 



ce 

 ij 

 a. 



2 

 JUNE 



10 2 



JULY 



10 2 



AUGUST 



10 20 



SEPTEMBER 



10 2 



OCTOBER 



3 I 



Figure 7. — Percentage of season's growth completed at different dates by Lake Erie yellow perch. Curve fitted to 



1928-29 data by inspection. 



Exceptional conditions may be expected also to 

 affect the course of growth in the early season 



(earlier onset or more rapid early-season increase 

 in some years). 



ANNUAL FLUCTUATIONS IN GROWTH 



Data are available for the analysis of fluctua- 

 tions in the growth of the yellow perch taken by 

 impounding nets in Lake Erie in the two periods, 

 1927-29 and 1943^8. Although the annual 

 increments of growth in the years 1924-29 were 

 computed from samples of the entire take by the 



nets, whereas the growth in 1940-48 was deter- 

 mined only from the legal-sized fish (8}^ inches and 

 larger), the average annual increments did not 

 differ greatly. The fluctuations in growth were 

 determined separately for each period and repre- 

 sent deviations from the average of the period to 



