FISHERY BULLETIN: VOL. 73, NO. 2 



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CATALINA IS. 



Figure 16.-Mean ages for suc- 

 cessive 20 mm standard length 

 groupings of male and female 

 Pimelometopon pulchrum. Sample 

 sizes and standard errors are 

 shown as in Figure 15. 



170 190 210 230 250 270 290 310 330 350 370 

 STANDARD LENGTH (20mm groups) 



The best picture, then, that can be drawn from 

 the present information is that rapidly growing 

 individuals may transform sooner than other 

 fishes of the same age. The bulk of the population, 

 growing at the average rate, eventually reaches a 

 "critical" size where most of them change sex. 

 Fishes that grow slowly may not change sex at all. 



The Breeding Season, Multiple 

 Spawning, and Fecundity 



Breder and Rosen (1966) have summarized the 

 information available on the spawning seasons of 

 labrids. In temperate species, most activity occurs 

 over a period of approximately 3 mo, most com- 

 monly in April, May, and June. The Catalina 

 population of P. pulchrum is exceptional in this 

 case, since spawning occurs from August to Oc- 

 tober. The two other wrasses commonly found at 

 Catalina Island also spawn later in the year than 

 other labrids. Oxyjulis californica spawns from 

 May until October (Bolin 1930), and Halichoeres 

 semicinctus probably spawns in late June, July, 

 and August (D. R. Diener, pers. commun.). The 



relatively late spawning seasons of these species 

 may be caused by upwelling along the southern 

 California coast which usually persists well into 

 June or July, resulting in a delay of inshore water 

 warming until that time (Quast 1968). 



Multiple spawning has not often been con- 

 sidered in studies of labrid breeding seasons. 

 Roede (1972) stated that labrids have "continuous, 

 successive spawning cycles," and based this view 

 upon the presence of many vitellogenic oocyte 

 stages in mature ovaries of the seven species she 

 investigated. She contended there is no resting 

 stage of the ovary, but a series of year-round 

 spawnings. At all times of the year she was able to 

 find ovaries with several stages of developing 

 oocytes as well as the stage 2 recruitment stock. 

 This clearly is not the case in P. pulchrum, where 

 the winter-resting ovary contains virtually no 

 signs of vitellogenesis. Active ovaries of the 

 California sheephead strongly resemble those pic- 

 tured by Roede (1972, plates II and III) for 

 Halichoeres and Hemipteronotus. The successive 

 spawnings within a restricted season indicated for 

 P. pulchrum may then be a curtailed version of a 



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