Relation of fish size with that of its otolith of Pama croaker, Otolithoides pama (Hamilton, 1822) from Narmada estuary, India

Abstract The relation of fish size with that of its otolith of pama croaker, Otolithoides pama (Hamilton, 1822) was established. Fish specimens were collected from the bagnet catch from Narmada estuary, India for a period of 8 months (November 2018 to June 2019). To understand the relationship between fish and otolith size, the sagittal otoliths were extricated, cleaned, measured, and photographed. The Otolith length (OL), Otolith breadth (OB), and Otolith weights (OW) were measured from each specimen to the nearest size of 0.01 mm and weight of 0.01 g. The observed length and weight of the fish were in the range of 85 to 288 mm (175.79±33.13 mm) and 3.0 to 186.56 g (43.68±27.67 g), respectively. The recorded otolith length, breadth, and weight were in the range of 2.65 to 12.54 mm (7.20±1.77 mm), 2.01-10.48 mm (5.95±1.33 mm), and 0.02 g to 0.75 g (0.23±0.11 g), respectively. The data fitted well to the power model for the OL, OB, OW, and fish length and weight. High values of the coefficient of determination (R2) were recorded between fish length and otolith length (R2 = 0.978), fish length and otolith weight (R2 = 0.931), fish length and otolith breadth (R2 = 0.985), fish weight and otolith length (R2 = 0.942), fish weight and otolith weight (R2 = 0.922), and fish weight and otolith breadth (R2 = 0.962). The study also depicted a high correlation of otolith dimensions with the size of the fish.