Age and growth of yellowfin tuna, Thunnus albacares, from the western Indian Ocean, based on otolith microstructure

Abs t r ac t . -Mic ro inc remen t s of otoliths of 151 yellowfin tuna, Thunnus albacares, caught in the western Indian Ocean by French and Mauritian purse seiners were used to establish growth 1' curves. On the basis of comparisons 'i among several otolith preparations (transverse or oblique sections, acetate replicas of the external face) and two methods of examination (light microscopy and scanning electron microscopy), we chose to observe transverse otolith sections in light microscopy to estimate age in days. The von B e r t a l e growth curve, FL