Work

Modeling the growth of red sea bream (Pagrus major) in cage culture: A comparative evaluation of nonlinear models

Year: 2025

Type: article

Abstract: The economic success of marine aquaculture for commercially significant species like Pagrus major hinges on predictable production cycles and efficient management. However, the growth dynamics of P. major in net-cage culture conditions are complex, shaped by fluctuating environmental variables and intensive management inputs, making accurate prediction of its growth trajectory a persistent industry challenge. Therefore, developing a robust and reliable growth model is a critical necessity for the sustainable development of the P. major industry. To address this practical need, a one-year growth monitoring study was conducted. Three nonlinear growth models, Logistic, Gompertz, and Von Bertalanffy, were fitted to the body weight data. The goodness-of-fit of these models was evaluated based on statistics such as the coefficient of determination ( R ²), Akaike information criterion (AIC), and Bayesian information criterion (BIC). The results showed that among the three models, the Logistic model provided the best fit for the body weight of net-caged P. major ( R ² = 0.980, lowest AIC and BIC values). Based on this model, the predicted asymptotic body weight ( A ) was 370.7 g. The age at the inflection point ( T i ) was 11.6 months, with a corresponding body weight at the inflection point ( W i ) of 185.3 g, and the maximum monthly weight gain ( M g ) was 43.9 g. The growth of P. major followed a sigmoid curve and exhibited distinct phasic characteristics: a relatively slow initial growth, a subsequent rapid growth period, and a decelerated growth rate in the later stage. These growth phase transitions coincided temporally with the dynamic changes in water temperature and salinity. This study provides a scientific basis and a practical model for the precision management, determination of optimal harvest size and timing, and evaluation of the economic efficiency of P. major aquaculture. • A pioneering comparison of growth models for a key cage-cultured fish species. • The Logistic model best describes the body weight growth of cage-cultured Pagrus major . • Water temperature is the key driver of growth, while salinity limits the early stages.

Source: Aquaculture Reports

DOI: 10.1016/j.aqrep.2025.103232