154 
Fishery Bulletin 111(2) 
Figure 3 
X-ray images of vertebrae sections that show band-pair progression of 5 OTC-marked juvenile Shortfin Mako 
( Isurus oxyrinchus) recaptured during this study off southern California. The small inset in each image shows the 
OTC fluorescence under UV light. Translucent or hyaline (rapid growth) bands or darker areas of vertebrae show 
periods of rapid growth, and opaque bands or lighter areas of vertebrae show periods of slow growth. Arrows indi- 
cate band-pair counts. 
