Wells et al. Age validation of |uvenile Isurus oxyrmchus tagged off southern California 
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Figure 1 
Map of study area in the Southern California Bight with tag and recapture locations (triangles) for (A) all recap- 
tured Shortfin Mako ( Isurus oxyrinchus) (OTC-marked and unmarked ( n =3 1 7 ) and (B) recaptured OTC-injected 
juvenile Shortfin Mako (n= 29) during the study period from 1996 to 2010. In panel B, black and gray arrows 
represent males and females, respectively, and the inset shows the more distant recapture locations. 
To elucidate the vertebral bands, we chose to du- 
plicate the “hard” (high-frequency) X-radiography 
technique of Cailliet and Bedford (1983) and Cail- 
liet et al. (1983), which was used in the only cen- 
trum aging study of Shortfin Mako off California 
to date. This type of high-resolution radiography, 
with industrial, fine-grain, high-contrast film for 
sharpness and sensitivity, operates in the range of 
