Smale and Goosen: Reproduction and feeding of Triakis mega/opterus 



997 



between dusk and dawn (Smale and Buchan, 1981), 

 making it vulnerable to nocturnal predators. Squid 

 iLoligo vulgaris reynaudii) is common throughout the 

 Agulhas Bank (the continental shelf between Cape 

 Town and Port Elizabeth) but become concentrated 

 inshore in spring and early summer, when it spawns 

 (Sauer and Smale, 1991; Augustyn et al., 1992). Egg 

 laying is concentrated on the bottom during the day 

 in waters 10-50 m deep (Augustyn, 1990; Sauer et 

 al., 1997). Squid are thought to be especially vulner- 

 able to predation during mating and spawning 

 (Smale, 1991; 1996). Sauer and Smale (1991) re- 

 corded T. megalopterus as one of the squid predators 

 in the vicinity of spawning aggregations, which il- 

 lustrates its ability to exploit a superabundant prey 

 resource by day, even though it normally appears to 

 hunt at night. 



In conclusion, it is evident that the habitat prefer- 

 ences of gully sharks make them vulnerable to ex- 

 ploitation by inshore fishermen. Their life history 

 traits — large size at maturity, prolonged gestation 

 period, and relatively small litter size — suggest that 

 this species is unsuitable for sustained harvesting 

 by either recreational or commercial fishing. 



Acknowledgments 



We are grateful to fishermen who donated specimens 

 for research and thank those colleagues who helped 

 with specimen collection in the field. We thank D. 

 Baird of the University of Port Elizabeth and anony- 

 mous referees for criticisms of an earlier draft. The 

 Foundation for Research Development and the South 

 African Network for Coastal and Oceanic Research 

 (Marine and Coastal Resource Programme) provided 

 financial support. 



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