210 



Fishery Bulletin 101(2) 



Days at liberty 



Lfl-uatl 



0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 16 1.1 



Growth rate (mm/day) 



[ i Ocean 1999 

 HB Estuary 1999 

 I 1 Estuary 2000 



Figure 8 



Summary of tag-recapture data from YOY bluefish during 1999 and 2000 at 

 southern New Jersey estuarine and ocean beaches, including days at liberty 

 and growth rate. 



the overwinter period because of size-selec- 

 tive mortality (see Sogard, 1997; Hales and 

 Able, 2001 ). Alternatively, the relatively large 

 numbers of presumed summer-spawned YOY 

 in collections implies that they could contrib- 

 ute substantially to the adult population. The 

 only prior analysis, that we are aware of, sug- 

 gested that the spring-spawned contingent 

 was the principal contributor to the adult 

 population (Chiarella and Conover, 1990). 

 Regardless of the habitats used, the relative 

 contribution by the summer-spawned indi- 

 viduals to the adult population could vary 

 over annual or decadal scales. More attention 

 to broad geographical responses over longer 

 temporal periods is probably necessary to 

 resolve the relative contribution issue of the 

 different cohorts. 



Residency and movements 



Our understanding of the importance of 

 ocean habitats to YOY bluefish is con- 

 founded by a lack of information about the 

 movements of these fast-swimming fishes. 

 Collections at northern New Jersey beaches 

 suggests their occurrence and abundance 

 may be sporadic based on the lack of consis- 

 tent catches over time at the sites sampled 

 (Fig. 4). The same pattern was observed in 

 the study area during 1999 and 2000 (Rowe 

 et al.^). This sporadic abundance could be 

 due to several factors including inshore-off- 

 shore movements from the beaches to deeper 

 water beyond the reach of seine samples, as 

 appears to occur on estuarine beaches on a 

 diel period (Buckel and Conover, 1997), or 

 movements along the beach. A similarly 

 variable pattern of occurrence has also been 

 noted for beaches in South Africa (van der 

 Elst, 1976). 



The results of the tag and recapture ef- 

 forts indicated that at least some of the YOY 

 were resident on an estuarine beach for a 

 considerable portion of the summer. Per- 

 haps the number of recaptures (0.76-3. 4%) 

 would have been higher if not for the three 

 hurricanes that occurred in the region 

 during September 1999 that could have 

 contributed to movement from shallow 

 beaches into deeper waters of the estuary 

 or into the ocean. The only other tag-recap- 

 ture study of YOY (<270 mm FL) bluefish, 

 of which we are aware, occurred in Moreton 

 Bay, Queensland, Australia (Morton et al., 

 1993). The high rate of returns (11';; ) from 

 the externally tagged fish in that study was 

 attributed to the intensive fishery for this 

 species and the fact that sheltered estuaries 

 within the study area presumably provided 



