FISHERY BULLETIN: VOL. 86, NO. 2 



10 



30 JULY 



*T*- -T 



13 AUG 



• f " -y 



SEPT 



.uIL 



ii iJ I 



23 SEPT 



3 6 9 12 15 18 21 24 



FORK LENGTH (cm) 



The analysis was then expanded to the remain- 

 ing samples of YOY bluefish from Great South 

 Bay that had not been aged. The above length-age 

 equations were used to estimate date of first ring 

 deposition from the dates of capture for all YOY 

 captured in each year of sampling from Great 

 South Bay. This exercise revealed that the vast 

 majority of YOY bluefish in our collections from 

 Long Island had dates of first ring deposition in 

 late March, April, and early May (Fig. 10). The 

 weighted mean date of first ring deposition was 8 

 April 1985 and 14 April 1986. 



The age-length equations for YOY bluefish 

 from Great South Bay were not applied to collec- 

 tions from Jamaica Bay or the Hudson River. Pre- 

 liminary analyses suggested that the age-length 

 equation for fish from the Hudson River differs 

 substantially from those in Great South Bay, 

 probably owing to a difference in growth rate. 

 Geographic variation in the pattern of recruit- 

 ment and in the age-length relationships of YOY 

 bluefish are being further investigated. 



DISCUSSION 



Recruitment of YOY Bluefish 

 to New York 



In both 1985 and 1986, the arrival of YOY blue- 

 fish on the south shore of Long Island was abrupt. 

 Within about a 1-wk period, CPUE went from 0.0 

 to 14-18 fish/seine haul. CPUE then remained 

 high for the next two months until declining in 

 August and September when the fish probably 

 became too large to be efficiently sampled by our 

 techniques. These data suggest that the YOY 

 bluefish recruit to the shore zone as a sudden 

 pulse. The timing of this recruitment event is ap- 

 parently variable, differing by about two weeks 

 among the two years of our study. The appear- 

 ance of fish 3-6 weeks earlier on the south shore 

 (Great South Bay) than on the north shore (Se- 

 tauket Harbor) of Long Island suggested that 

 these fish arrive from offshore waters to the 

 south. 



Temperature probably influenced the time of 

 arrival of YOY bluefish in the shore zone. In both 

 years of our study, YOY bluefish appeared as 

 temperatures reached about 20°-24°C. In Octo- 

 ber, after temperatures dropped to the middle 



Figure 6. — Length-frequency distributions for YOY bluefish 

 (no.) from the Hudson River, NY, 1986. 



244 



