Natanson et al.: Age and growth estimates for Carcharhinus obscurus 



125 



is the best estimate available for the dusky shark. 

 However, it should be kept in mind that the vertebral 

 growth curve generated for the dusky shark may also 

 underestimate age at maturity and maximum age. 



Acknowledgments 



We are grateful to the many fishermen and tourna- 

 ment officials who voluntarily provided us with data 

 and specimens for examination. We are particularly 

 indebted to commercial fishermen Tris Colket and 

 Eric Sander who dissected vertebrae and provided 

 precise length measurements on dusky sharks. We 

 appreciate the statistical expertise provided by 

 Carolyn Belcher and the assistance in field dissec- 

 tions provided by our colleagues C. Stillwell and H. 

 W. Pratt of the Apex Predator Investigation. 



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