708 



Fishery Bulletin 100(4) 



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Figure 15 



Conceptual model depicting the life history of Thyrsites atun 

 in the southern Benguela ecosystem, including spawning 

 grounds, distribution and transport of eggs and larvae, and the 

 nurserv areas. 



those small enough to be eaten by young snoek) are least 

 abundant inshore. 



Given that the majority of the alternative prey are most 

 abundant at some distance from the coast — euphausids 

 between 10 and 20 km from the coast (Pillar, 1986; Hutch- 

 ings et al., 1991), lanternfish, and lightfish between the 

 75- and 300-m isobaths (Hulley and Prosch, 1987), and 

 mantis shrimp in the 20-200 m depth zone (Griffiths and 

 Blaine, 1988) — it is likely that juvenile snoek move farther 

 offshore when anchovy recruits leave the area, i.e. beyond 

 the normal operating range of line fishermen in regions 

 0-2 (hence the seasonal drop in handline CPUE). 



Acknowledgments 



The author thanks the Demersal, Pelagic, and Linefish 

 Sections of the Chief Directorate of Marine and Coastal 

 Management, for assisting with the collection of biological 

 material and providing CPUE and length-frequency sum- 

 maries for research cruises and commercial fisheries; the 

 Sea Bird Section for gannet-diet data; the Reprographics 

 Section for producing the final drafts of the figures; Y. 

 Melo for assistance with histological preparation and 

 interpretation; M. Lapinsky for assistance with the identi- 

 fication of squid beaks; A. Boyd and G. Nelson for helpful 

 discussions on the oceanography of the Benguela region; 

 and Robert Crawford, Pierre Freon, Larry Hutchings, and 

 three anonymous referees for valuable comments on the 

 manuscript. This research was subsidized by the Marine 

 Living Resources Fund. 



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