Age, growth, and length-weight relationship of roosterfish (Nematistius pectoralis) in the eastern Pacific Ocean

Growth of roosterfish (Nematistius pectoralis) was estimated by analyzing daily growth increments of sagittal otoliths collected from individuals captured in El Golfo Dulce, Costa Rica during 2013-2014 and in southern Baja California Sur, Mexico during 2010-2015. Isometric growth was observed for all individuals and no significant differences were observed in the length-weight relationships between sexes or locations. Age estimates ranged from 18 d (0.05 years) to 545 d (1.5 years), although 26% of otoliths (57-133 cm) were not legible because narrow daily growth increments were difficult to differentiate in older fish. Individual growth parameters indicate that roosterfish grow at a rapid rate during the first year of life, reaching sizes of around 60-70 cm in fork length. Although future field validation is necessary, the results of our study provide insight into the life history of this valuable resource of the eastern Pacific Ocean.