987 



Abstract. -The spotted gully shark, 

 TYiakis megalopterus, was sampled op- 

 portunistically over a 12-year period 

 from catches of shore and ski-boat fish- 

 ermen using hooks and lines. Most 

 specimens (89.6%) were taken from 

 rocky reefs less than 10 m deep, 8% 

 were caught at 11-20 m, and only 2.4% 

 were recorded from waters more than 

 20 m deep. The reproductive biology of 

 35 males and 87 females was examined. 

 The spotted gully shark exhibits apla- 

 cental viviparity. Size at 50% maturity 

 for males is ca. 1320 mm total length 

 (TL) and for females ca. 1450 mm TL. 

 Maximum sizes recorded here were 

 1520 mm TL. for males and 2075 mm 

 TL for females. Gestation appears to 

 last 19-21 months. The female repro- 

 ductive cycle may be 2-3 years, depend- 

 ing on the time between pregnancies. 

 The sex ratio of embryos was found to 

 be 1:1 but the postpartum male:female 

 ratio was 1:2.5. Size at birth was esti- 

 mated to be 420-450 mm TL. The 

 smallest free-swimming individual re- 

 corded was 576 mm TL. Number of 

 embryos per pregnancy ranged between 

 5 and 15, with a mean of 9.7. A total of 

 110 stomachs were examined in the feed- 

 ing study. Diet changed with increase in 

 shark size. Small sharks (<1 m) preyed 

 mainly on Cape rock crabs, Plagusia 

 chabrus (78% of mass), whereas sharks 

 of 1-1.4 m preyed largely on Cape rock 

 crabs (48%) and cephalopods (33%). Te- 

 leosts were more important for sharks 

 larger than 1.4 m (54% ); most of these 

 prey were associated with rocky reefs. 



Reproduction and feeding of 



spotted gully shark, Triakis megalopterus, 



off the Eastern Cape, South Africa 



Malcolm J. Smale 



Port Elizabeth Museum 



P.O. Box 13147 



Humewood, Port Elizabeth 



6013 South Africa 



E-mail address pemmis g zoo upe ac za 



Andre J. J. Goosen 



P.O. Box 1109 

 Milnerton, Cape Town 

 7435 South Africa 



Manuscript accepted 21 January 1999. 

 Fish. Bull. 97: 987-998 (1999). 



The genus Triakis Miiller and 

 Henle, 1838, commonly called leop- 

 ard shark, comprises small to mod- 

 erately large, harmless, stocky 

 sharks that feed on invertebrates 

 and fish. Triakis is currently re- 

 stricted to five species: Triakis 

 acutipinna Kato, 1968 (sharpfin 

 houndshark); T. rnaculata Kner and 

 Steindachner, 1867 (spotted hound- 

 shark); T. scyllium Miiller and Henle, 

 1839 (banded houndshark); T. semi- 

 fasciata Girard, 1854 (leopard shark); 

 and T megalopterus (Smith, 1849) 

 (sharptooth houndshark or spotted 

 gully shark; Compagno, 1988). 



Triakis megalopterus is a stout 

 houndshark with a broadly rounded 

 snout and a large mouth with small, 

 pointed teeth. The head and body 

 are gray or bronze above, usually 

 with numerous small black spots, 

 and white underneath (Bass et al., 

 1975). It is endemic to southern Af- 

 rica (Compagno et al., 1989), where 

 it occurs from northern Namibia, at 

 about 21°45'S, 13°57'E, to Coffee 

 Bay in Eastern Cape, South Africa, 

 at 31°59'S, 29°09'E. The species is 

 a common inshore bottom-dwelling 

 shark of temperate continental wa- 

 ters, where it is caught by anglers 

 in shallow subtidal waters. It pre- 

 fers rocks and crevices in the shal- 



lows and is confined to water shal- 

 lower than 50 m along the Cape 

 coast (Bass et al., 1975; Compagno 

 etal., 1989, 1991). 



Very little has been published on 

 the biology of this species (Bass et 

 al., 1975). Although all five species 

 o{ Triakis are viviparous, they lack 

 yolksac placentas and the embryos 

 obtain nourishment from their yolk 

 sacs (Bass et al., 1975; Castro, 1983; 

 Compagno, 1984; Kusher et al., 

 1992). Bass et al. (1975) and Com- 

 pagno ( 1984 ) provided some informa- 

 tion on the food habits of T mega- 

 lopterus, noting the presence of crabs 

 {Plagusia chabrus), teleost fishes, and 

 one small shark (Scyliorhinus capen- 

 sis) in stomach contents. 



At present, there is no scientific 

 information that could guide man- 

 agement decisions on T megalop- 

 terus, with the possibility of a small 

 population size and limited range 

 distribution (Compagno et al. 1989; 

 Goosen, 1997), this species could be 

 vulnerable to overexploitation in in- 

 shore multispecies shark fisheries. 

 Off California, T semifasciata has 

 declined in abundance and conse- 

 quently management measures 

 have been proposed there (Smith 

 and Abramson, 1990; Cailliet, 

 1992). 



