Table 16. --Weekly survival rates (s), weekly exploitation rates (;j), experimental fishing mortal- 

 ity rates (F), and other-loss rates (X) for 30 groups of tagged fish. 



Summing over i 



and, since 



it is evident that 



k k 



J = 1 i = 1 



S Ri 



u^ - i = 1 



^ =M7 



1-S 



Values for s and /j for the 30 experiments with recovery 

 periods of 2 wk or more are Usted in Table 16. Weekly 

 survival rates varied from 0.139 for the group released 

 on 9 August 1938 in lower Chatham Strait to 0.745 for 

 the group released on 10 August 1941 in middle 

 Chatham Strait and averaged 0.394. Weekly exploita- 

 tion rates varied from 0.142 on 25 July 1942 in upper 

 Chatham Strait to 0.452 on 20 July 1941 in middle 

 Chatham Strait and averaged 0.250. 



Once /J and s have been estimated, the exponential 

 fishing mortality rate, F, and "other-loss" rate, X, 

 (Paulik 1963) for the tagged fish can be calculated. 



33 



