Age and growth of blue marlin Makaira nigricans from the central western Atlantic Ocean

Atlantic blue marlin fin spines were sampled from Venezuelan fleets during 2003–2008 for the purpose of estimating age and growth. Transverse sections of the second spine from the first anal fin were sampled from 1708 individuals. Of these, 1638 (95.9%) were readable (774 males, 744 females and 120 indeterminate). Males ranged in size from 130 to 254 cm LJFL, females from 126 to 370 cm LJFL. Samples were scored for visible growth annuli and age-corrected for early annuli lost as a result of increased spine core vascularization. Maximum age estimates based on visible annuli were 19.6 yrs for males and 31.3 yrs for females. After age-correction the maximum age estimates were revised to 43.4 and 43.5 for males and females, respectively. The von Bertalanffy growth model and alternate variant models are presented for the observed individual LJFL at-age data, and three derived data sets: (1) mean observed LJFL at age, (2) all back-calculated LJFLs at each age, (3) mean back-calculated LJFL at each age for males, females, and combined sex.