FISHERY BULLETIN: VOL. 84, NO. 3 



tween November and June. Only the ovarian cycle 

 seems to correspond closely to the local environmen- 

 tal conditions that seem optimal for larval growth 

 and survival. Possibly, the genes that are respon- 

 sible for local adaptation of spawning stocks are sex 

 linked for females and are selected through larval 

 survival. 



Annual Production of Eviscerated 

 Weight and Reproductive Tissues 



Although Pacific herring usually have only one 

 major spawning per site in the Auke Bay vicinity, 

 there may be a succession of lesser spawnings each 

 spring. Unspawned fish are rarely seen as late as 

 July (author's observations and comments by salmon 

 fishermen who jig herring for bait). Although Wing 

 (see footnote 2) recorded spawnings in Auke Bay 

 between 24 and 29 April 1973, herring must spawn 

 for at least 2 mo in Auke Bay because some fish 

 sampled in 1973 were partially spawned or ripe and 

 running in May and June (Fig. 7). Presumably, local 

 conditions influence the number of eggs deposited 

 on any date. 



The relationship between fecundity, as indicated 

 by mature ovarian weight, and BL was greater than 



cubic, in agreement with data on other clupeiod 

 species (Blaxter and Hunter 1982). Samples of Auke 

 Bay herring had an exponent of 3.94 (Fig. 8), within 

 the range (3.07-4.50) for Atlantic herring as given 

 by Paulson and Smith (1977), from the literature. 

 These authors gave an exponent of 3.32 for Pacific 

 herring they sampled in Prince William Sound. 

 Perhaps, the exponent for fecundity would have 

 been higher for the herring Paulson and Smith 

 sampled in Prince William Sound had their collec- 

 tions included smaller fish (their smallest were near 

 180 mm long, but fish as small as 130 mm were 

 available in samples from Auke Bay). The exponent 

 for testicular weight was considerably higher than 

 that for ovarian weight in Auke Bay herring (Fig. 

 8); however, the difference may not be real because 

 the confidence limits for the two exponents over- 

 lapped considerably. 



The scatter in the plots of gonad and testes 

 weights on BL for Auke Bay herring (Fig. 8) and 

 for Pacific herring from Prince William Sound (fig. 

 1 in Paulson and Smith 1977) indicate that some of 

 the herring may have been partially spawned when 

 they were collected (fully spawned fish were not 

 used in my data). If samples for fecundity are taken 

 in the spawning season, there is the risk that some 



MATURITY STAGE: 



1. IMMATURE 



2. SPAWNED OUT AND 

 REGENERATING 



3. REGENERATING 

 U. MATURING 



5. RIPE 



6. PARTIALLY SPAWNED 

 OR RIPE AND RUNNING 



7. SPAWNED OUT 



N = 21 38 80 59 20 55 80 54 30 7 29 



Figure 7.— Maturity of Pacific herring near Auke Bay, AK, by month (sexes combined). Numbers in boxes are percent- 

 ages of herring that were visually classified into maturity stages on examination. Total fish by month are given 

 in the bottom line. Data for February were extrapolated from January and March. 



716 



