Biometric Relationships between Otolith and Fish Size of the Main Demersal Resources of North Patagonia, Argentina

Abstract

Allometric power equations are generated using otolith length and width in order to estimate the total length of five demersal species inhabiting the San Matias Gulf, the second largest gulf in Argentina. The selected fish species are economically important resources in Argentina and have been identified as prey for the system's main predators. A total of 2,795 specimens were sampled, and data were fitted using the nonlinear least squares analysis. It is shown that the length and width of the otolith are good predictors of the total fish length. A slightly better regression fit is observed when otolith length was considered as a predictor. Statistically significant morphometric differences in regression models were observed between sexes, except for Acanthistius patachonicus. Results are discussed and compared with those reported by other authors.