1006 



Fishery Bulletin 97(4), 1999 



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Figure 5 



Daily frequencies for (A) pursuit and (B) avoidance behavior exhibited by adult winter flounder in the 

 research aquarium. 



estuary increased steadily between mid-February 

 and early March, concurrent with the rise in water 

 temperature (Fig. 8). Abundance remained relatively 

 stable for the remainder of the collection period. Of 

 the 389 winter flounder collected, 49% were female 

 (mean length=28.9 cm. SD=8.9) and 32.5% were male 

 (mean=25.1 cm, SD=6.9). Gender could not be deter- 

 mined for 18.5%, all of which were small individuals 

 considered to be age-1 fish (mean=10.2 cm, SD=2.3). 

 Females were significantly more abundant than 

 males (Table 1; F=4.62, P<6.05), with a sex ratio of 

 1.5 to 1, and this pattern was consistent throughout 

 the sampling period; analysis of variance (ANOVA) 

 showed a nonsignificant Date x Gender interaction 

 (P=0.58; Table 1 ). 



The majority of ripe female flounder were collected 

 in the first half of the survey period (Fig. 9A): all of 

 these fish were larger than 20 cm TL. Ripe females 

 were divided into two obvious groups based on 

 gonadosomatic index (GSI). Sixty-five percent of ripe 

 females had GSIs greater than 20% (mean=30.9. 

 SD=9.1). A second group of nearly spent females had 

 GSIs of 3-8%. All female winter flounder collected 

 after mid-March had GSIs less than 6%. 



lively 



Male winter flounder formed two size groups, small 

 fish ( <20 cm TL ) assumed to be age- 1 fish and larger 

 individuals (20-35 cm TL). Through the end of Feb- 

 ruary all males larger than 20 cm were reproduc- 



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