Age and growth of yellowtail snapper and queen triggerfish collected from the U.S. Virgin Islands and Puerto Rico

Opaque rings on sectioned otoliths and sectioned dorsal spines were used to age yellowtail snapper, Ocyurus chrysurus (N = 654) and queen triggerfish, Balistes vetula (N = 665), taken from U.S Virgin Islands and Puerto Rico trap and hook-and-line fisheries in 1983 and 1984. Annulus formation, validated by marginal increment analysis, occurred from March to May for yellowtail snapper and from February through March for queen triggerfish.The maximum age for yellowtail snapper was 17 years, compared with only 7 years for queen triggerfish. Mean back-calculated fork lengths (FL, mm) of yellowtail snapper aged 1, 5, 10, 15 and 17 years were 117, 287, 375, 455 and 505, respectively. Mean back-calculated lengths for queen triggerfish aged 1–7 years were 161, 229, 274, 307, 332, 356 and 378 mm FL, respectively. The von Bertalanffy growth equations for yellowtail snapper and queen triggerfish were L_t=502.5 (1−e^{−0.139(t + 0.955)}) and L_t=415(1−e^{−0.30(t + 0.600)}) respectively, where t = age in years. The length-weight relationship for yellowtail snapper was W = 0.000117FL^2.6504, where W = weight in grams and was W = 0.000101FL^2.750 for queen triggerfish. Data revealed that yellowtail snapper live longer than previously reported and grow at a rate similar to other western Atlantic lutjanids. Queen triggerfish studied were not as old as expected, probably because of fishing gear selectivity.