Age, Growth, and Natural Mortality of Whitebone Porgy, Calamus Leucosteus, From the Southeastern United States

Abstract

Ages of whitebone porgy (Calamus leucosteus) (n = 559) from southeastern U. S. commercial and recreational fisheries from 1975 – 2017 were determined using sectioned otoliths. Opaque zones were annular, forming April – July (peaking in June). Ages ranged from 2 – 19 years, and the largest fish measured 513 mm TL (total length, mm). Body size relationships were: TL = 1.09 FL + 16.07 (n = 469, r² = 0.97), FL = 0.89 TL – 6.39 (n= 469, r² = 0.97), W = 2.8 x 10^-5 TL^2.91 (n = 462), and W = 6.8 x 10^-5 FL^2.82 (n = 417) where W is total weight (grams, g) and FL is fork length (mm). The von Bertalanffy growth equations were L_t = 365 (1 - e^{-0.35 (t + 1.37)}) (n = 559) for all areas combined, L_t = 365 (1 - e^{-0.55(t + 0.00)}) (n = 185) for fish from North Carolina through Cape Canaveral, Florida, and L_t = 368 (1 - e^{-0.25 (t + 2.51)}) (n = 374) for fish from southeast Florida. Mean size-at-age was significantly different between regions for ages 4 – 9, (92% of total samples). Point estimates of natural mortality were M = 0.22 and M = 0.30 for northern- and southern-region fish, respectively, while age-specific estimates of M were 0.85 – 0.55 y^-1 for ages 2– 19 for the northern region and 0.41 – 0.26 (ages 2-14) for southern region fish. This study presents updated life history parameters for whitebone porgy from the Atlantic waters off the southeastern United States.