these tests were conducted during March-April 

 when juvenile mackerels are rare in the coastal 

 waters of South Carolina. 



In 1986 we collected juvenile mackerels during 

 July through October. Because of incomplete tem- 

 poral sampling, we do not know if they were 

 present earlier and later in the year in this re- 

 gion. Based on the occurrence of early larval 

 stages, spawning of both mackerels in the South 

 Atlantic Bight extends from May through at least 

 September (Collins and Stender 1987). If growth 

 rate estimates of ca. 3 mm/day for juveniles are 

 correct (M. R. Collins, unpubl. data), king mack- 

 erel spawned in early May could be recruited into 

 the bycatch of the shrimp fishery in June. Late- 

 spawned fish from the previous year may also be 

 present at this time. In South Carolina, the open 

 season for commercial trawling for penaeid 

 shrimps in state waters usually extends from 

 June through December, which coincides with the 

 presence of juvenile mackerels in the heavily 

 fished nearshore waters. In addition, mackerels 

 were much more abundant in tows made in 

 depths <9 m, which includes the preferred 

 shrimping areas, than in deeper waters. This may 

 be due either to greater abundance in these 

 depths or to greater catchability in response to 

 the fact that the trawl nets fish a larger portion of 

 the water column in shallower areas. 



It is difficult to accurately estimate the bycatch 

 of mackerels in the commercial shrimp fishery 

 owing to lack of current, detailed information 

 from throughout the region on number of vessels, 

 effort expended, gears used, and areas fished. 

 However, our catch rates suggest that the impact 

 of tongue nets on mackerel stocks may be signifi- 

 cant. As the current status of these stocks is such 

 that strong restrictions have been imposed on 

 both the recreational and commercial fisheries, it 

 is unfortunate that the situation may be exacer- 

 bated by a potentially large bycatch of juvenile 

 mackerels in the shrimp fishery. More informa- 

 tion is needed on the ecology and behavior of 

 young mackerels, and their vulnerability to vari- 

 ous gears, in order to resolve this conflict. 



Acknowledgments 



We wish to express our appreciation to the 

 many people who assisted in the tedious tasks of 

 collecting and processing trawl samples over the 



years, including the captains and crews of the 

 vessels involved. This work was sponsored by the 

 National Marine Fisheries Service (Southeast 

 Fisheries Center), the South Carolina Wildlife & 

 Marine Resources Department, and the Sport 

 Fishery Research Foundation. 



Literature Cited 



COLLETTE. B B . AND J L RUSSO 



1984. Morphology, systematics, and biology of the 



Spanish mackerels (Scomberomorus , Scombridae). 



Fish. Bull., U.S. 82:545-692. 

 Collins, M R . and B W Stender. 



1987. Larval king mackerel (Scomberomorus cavalla), 

 Spanish mackerel (S. maculatus), and bluefish iPo- 

 matomus saltatrix ) off the southeast coast of the United 

 States, 1973-1980. Bull. Mar. Sci. 41:822-834. 

 Edwards. M L. 



1987. The shrimp trawl. Natl. Fisherman 67(13):89-92. 

 Fahay, M P 



1975. An annotated list of larval and juvenile fishes cap- 

 tured with surface-towed meter net in the South Atlantic 

 Bight during four RV Dolphin cruises between May 1967 

 and February 1968. U.S. Dep. Commer., NOAA Tech. 

 Rep. NMFS SSRF-685, 39 p. 

 Manooch. C S , III 



1979. Recreational and commercial fisheries for king 

 mackerel, Scomberomorus cavalla , in the South Atlantic 

 Bight and Gulf of Mexico, U.S.A. In E. L. Nakamura 

 and H. R. Bullis (editor), Proceedings of the mackerel 

 colloquium, p. 33-41. Gulf States Mar. Fish. Comm., 

 Brownsville, TX. 

 Manooch. C S , III. E L. Nakamura, and A B Hall 



1978. Annotated bibliography of four Atlantic scombrids: 

 Scomberomorus brasiliensis , S. cavalla, S. maculatus, 

 and S. regalis. U.S. Dep. Commer., NOAA Tech. Rep. 

 NMFS Circ. 418, 166 p. 



Mark R Collins 

 Charles A. Wenner 



Marine Resources Research Institute 

 South Carolina Wildlife and Marine 



Resources Department 

 P.O. Box 12559 

 Charleston, SC 29412 



12559, Charleston, SC 29412, pers. commun. May 1987. 



STOMACH CONTENTS OF COMMERCIALLY 



CAUGHT HUDSON RIVER STRIPED BASS, 



MORONE SAXATILIS , 1973-75 



The Hudson River estuary is a detritus-driven 

 ecosystem. Only a few of the 100 or more reported 

 fish species function as tertiary piscivores more 

 typical of a grazing food chain. Of these few spe- 

 cies, which include the American eel, Anguilla 

 rostrata, and the summer-transient juvenile 



FISHERY BULLETIN: VOL. 86, NO. 2. 1988. 



397 



