AGE, GROWTH, MATURITY, AND SPAWNING OF SPANISH MACKEREL, SCOMBEROMORUS-MACULATUS (MITCHILL), FROM THE ATLANTIC COAST OF THE SOUTHEASTERN UNITED-STATES

Sectioned sagittae of 1,039 Spanish mackerel, Scomberomorus maculatus (Mitchill), from the Atlantic coast of the southeastern United States (North Carolina to Florida) were examined. The oldest male was age 6 a nd the oldest female age 11. Marginal increment analysis indicated tha t annulus formation peaks in May-June. The von Bertalanffy growth equa tion parameters (L(infinity), k, and t0, respectively) were: 538 mm fo rk length (FL), 0.31, and -2.31 for males; 723 mm FL, 0.24, and -1.80 for females; and, 760 mm FL, 0.18, and -2.44 for sexes combined. Gonad s from 1,742 specimens were examined histologically to assess reproduc tive state. Mature gonads were present in 89% of age-0 males and 100% of older ages, whereas 5% of females were mature at age 0, 95% at age 1, and 100% at older ages. Females matured at 288-450 mm FL and males matured at 209-336 mm FL. Estimates of length at 50% maturity (L50) we re 35.8 cm FL for females and 23.9 cm FL for males. Females were in sp awning condition from May to August; ripe males were captured April-No vember. Resting specimens were included in the assessment of maturity and the disadvantages of their inclusion are discussed.