Age and Growth of Young-Of-The-Year (YOY) California Halibut (Paralichthys calif ornicus) , from Northwestern Baja California

Abstract

Ninety-nine young-of-the-year (YOY) California halibut (Paralichthys <br /><br />calif ornicus), collected from Bahia de Todos Santos (BTS, n = 29), Estero de <br /><br />Punta Banda (EPB, n = 36) and Bahia de San Quintin (BSQ, n = 34), Baja <br /><br />California (Mexico), were aged using sagittal otoliths. Our preliminary age de- <br /><br />termination by use of annual increments in otoliths of California halibut from <br /><br />Bahia de Todos Santos, and Estero de Punta Banda, Baja California (Mexico), <br /><br />showed that a minimum length of 180 mm SL could be set as limit size for <br /><br />halibut young-of-the-year. The separate age-length relationships between YOY <br /><br />halibut from these three study sites are described by linear equations: BTS: y = <br /><br />-4.943 + o.5x, r 2 = 0.899; EPB: y - -12.85 + 0.496x, r 2 = 0.903; BSQ: y = <br /><br />-28.19 + 0.5 19x, r2 = 0.967. The "y" is the standard length (mm) and the "x" <br /><br />is the age in days. Age was equivalent to the days from hatching. The Analysis <br /><br />of Covariance indicated no significant differences in growth rates between the <br /><br />three sites (ANCOVA, p = 0.419). Therefore, all data were combined to deter- <br /><br />mine one overall growth equation for young-of-the-year: y = —14.09 + 0.492x, <br /><br />(n = 99, r 2 = 0.907, S.E. constant = 6.25, S.E. slope = 0.059). This equation <br /><br />established a limit size for young-of-the-year halibut as 173 mm SL, with a range <br /><br />of readings between 168 to 180 mm.