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Fishery Bulletin 101(4) 



These techniques can be used to complement morphomet- 

 ric identification (Chff and Wilson, 1994; Last and Stevens, 

 1994; Naylor and Marcus, 1994) or can be used to identify 

 "cryptic" species when morphological identification cannot 

 be done. Other "cryptic" species caught in beach meshing 

 and by recreational fisheries can be added to the DNA da- 

 tabase, such as hammerhead sharks (Sphyrna spp.) which 

 are commonly caught and are recorded in catch records to 

 genus level only (Pepperell, 1992; Reid and Krogh, 1992; 

 Chan, 2001). Although this project positively identified 

 six species from the genus Carcharhinus, other species of 

 this genus are known to inhabit the NSW coastline (Ste- 

 vens, 1984; Last and Stevens, 1994). During the warmer 

 months, when the northern currents extend farther south 

 to the Sydney region, transient tropical Carcharhinus spp. 

 may appear off the coast. In the northern regions of NSW, 

 there have been recorded catches of the blacktip reef shark 

 (C melanopterus) by shore-based anglers (Gartside et al., 

 1999). Although transient tropical whaler sharks may not 



have permanent stocks in NSW waters, it is important to 

 discern them from resident Carcharhinus spp. prior to 

 any species-specific stock assessment. Given the number 

 of shark species and difference in life histories (Last and 

 Stevens, 1994; Smith et al., 1998), identification to species 

 level is crucial. 



The use of genetic techniques allows, for the first time, 

 accurate identification of species of whaler sharks that 

 were landed by recreational fisheries and caught in pro- 

 tective beach meshing in NSW and that have been his- 

 torically recorded to genus level. Continual sampling and 

 formal identification are required for comparison of catches 

 between species oi Carcharhinus. Genetic techniques have 

 the potential to be used for all other shark species and 

 fisheries within the Australian Fishing Zone (AFZ). The 

 use of genetic techniques has been employed in the field 

 of law enforcement to prevent the selling of protected fish 

 species at local fish markets where the majority of the 

 carcass is not retained (Ward et al., 1999). This use could 



