FISHERY BULLETIN: VOL. 82, NO. 1 



Table 4.— Linear regressions of fish length on log (oto- 

 lith diameter). 



Lough et al. (1982); they have also been described in 

 the otoliths of larval turbot, Scopthalmus maximus, 

 (Geffen 1982) and Arcto-Norwegian cod, Gadus 

 morhua, (Gj0saeter and Tilseth 1982). Increments 

 have also been found inside the nucleus in Atlantic 

 herring (Lough et al. 1982), in three species of the 

 genus Lepomis, and in the Mozambique mouth- 

 breeder, Tilapia mossambica, (Taubert and Coble 



Fie.l'RE 4. — Relationship of fish length to log (otolith 

 diameter) for seven groups of Pacific herring lar- 

 vae. Open circles in 1982 are 1982A and solid cir- 

 cles are 1982B. See Table 4 for the regression 

 equations. 



I 



r- 



o 



LU 



_l 



Q 



< 



Q 

 Z 

 < 



r- 



25 r 



20 - 



10 



5 



2 5 



20 



5 



25 



20 



10 



1980A 



St" 



1980B 



«r 



_j i i i_ 



1980C 



1981A 



1981B 



1982 



  



20 



5 



100 



250 20 



50 100 250 



OTOLITH DIAMETER (LJM) 



slope of the 1980B group was not significantly dif- 

 ferent from either the feeding groups or the starving 

 groups because of its high standard error. The four 

 fed groups were pooled to give a single regression {n 

 = 191, r= 0.95, P< 0.001): 



Fish length = 30.90 + 12.49 log (otolith 

 diameter). 



The three starved groups could not be pooled 

 because of the different growth and feeding histories 

 of each group. 



DISCUSSION 



The first class of thin rings was found in the otoliths 

 of Atlantic herring larvae by Geffen (1982) and by 



1977). In at least one species offish, the mummichog, 

 Fundulus heteroclitus, these nonregular rings are 

 regular daily rings that are deposited before hatching 

 (Radtke and Dean 1982). The relationship between 

 the number of nonregular rings, the age and size of 

 the fish, and rearing conditions can only be deter- 

 mined with more experimental work, particularly on 

 the sagittae of embryo and yolk-sac herring. 



Presence of the thin rings in the 1980 fish and their 

 absence in the 1981-82 fish was not the result of 

 genetic differences between the eggs of the lower 

 east coast stock and the eggs of the lower west coast 

 stock. The sagittae of many small (length range = 9- 

 20 mm) wild herring larvae captured from Bamfield 

 Inlet in 1981 and 1982 were found to have several 

 thin, faint rings around the nucleus (McGurk unpubl. 

 data). It seems more reasonable to hypothesize that 



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