DeMARTINI and FOUNTAIN: OVARIAN CYCLING FREQUENCY IN QUEENFISH 



RESULTS 



Spawning Season and Gonad Maturation 



Queenfish ovaries accelerate development in 

 February when daylight lengthens beyond 10 h 

 and nearshore water temperatures are 15°-16° 

 C. Ovaries increase to their maximum relative 

 weight in April-May and decline through August 

 until a resting stage recurs in September (Fig- 

 ure 2A). During February-September, nearshore 

 water temperatures in general increase to 17°-19° 

 C, although aperiodic bouts of upwelling (13°- 14° 

 C water) occur (J. Reitzel^). Ovaries mature at a 



GI of 40, when the diameter of Gilson's fluid-fixed 

 (nonhydrated) oocytes reaches 350 ixm (Figure 3). 



Body Size and Time of Spawning 



The first sexual maturation of females begins at 

 a length of 10-10.5 cm. The proportion of sexually 

 active females increases with body size until, at a 

 length of about 12 cm SL, virtually all females are 

 spawning by midseason (Table 2). Larger females 

 (>12 cm, age II and older, DeMartini et al."*) start 

 spawning earlier and finish spawning later in the 

 year than fish ^12 cm SL (Table 2, Figure 4). 

 Duration of spawning varies from 3 mo for first 



^Reitzel, J. 1979. Physical/chemical oceanography. In 

 Interim Report of the Marine Review Committee of the Cali- 

 fornia Coastal Commission. Part II: Appendix of Technical 

 Evidence in Support of the General Summary, March 12, 1979, p. 

 6-23. Unpubl. rep. Marine Review Committee Research Center, 

 533 Stevens Avenue, Suite E-36, Solana Beach, CA 92075. 



■'DeMartini, E. E., K. M. Plummer, andT. O.Moore. Age and 

 growth of the queenfish { Seriphus politus) , with back-calculated 

 length-at-age estimates based on sections of otolith sagittae. 

 Manuscr. in prep. Marine Science Institute, Univ. Calif., Santa 

 Barbara, CA 93106. 



FIGURE 2. — ( A) Mean gonad indices of female queenfish (of all body sizes) collected September 1978-September 1979. Indices of day and 

 night sample fish plotted separately Sample sizes and 95% confidence limits are mdicated. (B) Percent frequency occurrence of adult 

 female queenfish with ovaries containing oocytes in hydrated condition during March-August 1979. Fish are from daytime collections 

 at 5-11 m depths. Noted are the numbers of sample fish, dates of new moon, and maximum range in heights of highest and lowest tides 

 each day. 



549 



