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FISHERY BULLETIN: VOL. 86, NO. 2 



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JUNE JULY AUG SEPT OCT 



FlGlTRE 2.— Catch per unit effort (CPUE) of YOY bluefish from 

 Great South Bay, NY, plotted with the mean water temperature 



Jamaica Bay and the Hudson River 



The length-frequency distributions of YOY 

 bluefish from Jamaica Bay in June, July, and 

 August were similar to those from Great South 

 Bay (Fig. 5). Fish lengths in June were unimodal. 

 Subsequent collections contained progressively 

 larger fish that were also unimodal in length dis- 

 tribution. 



Sampling in the Hudson River began on 16 

 July 1986 and continued through 8 October. The 

 size ranges of YOY bluefish in the July and Au- 

 gust samples were similar to those from Great 

 South Bay, although the length distribution on 30 

 July appears bimodal (Fig. 6). The length distri- 

 butions from the 10 and 23 September collections 

 were especially broad. In particular, the 23 Sep- 

 tember sample contained a group offish that were 

 much smaller (10-14 cm FL) than the mean size 

 at this time in Great South Bay (Fig. 4), together 

 with a second group of larger fish that correspond 

 more closely in size with those collected else- 

 where (18-24 cm). 



Frequency of Ring Deposition 



In tetracycline-injected YOY bluefish, the 

 number of rings beyond the tetracycline mark (Y) 

 and the number of days after injection (X) had a 

 1:1 correspondence (Fig. 7). The relationship was 

 described by the equation Y = 0.97 LY - 0.287 

 in = 27, r = 0.996). The slope did not differ signif- 

 icantly from 1.0 (^test, P > 0.1). 



Growth rate of the caged fish was slightly 

 greater than that of field fish and survival was 

 high (80%) with mortalities occurring only in the 

 first few days of the 61-d experiment. The in- 

 crease in mean fork length was 1.7 mm/day 

 among the caged fish, as compared with about 1.3 

 mm/day for fish from field collections during the 

 same time period (Fig. 4). Hence, the caged fish 

 did not appeEir to be adversely affected by confine- 

 ment. 



240 



