Golden pompano (Trachinotus ovatus) ranks among the most commercially important and high-yield marine finfish species in Chinese mariculture. In response to the requirement for monitoring fish in aquaculture, this study employed Adaptive Resolution Imaging Sonar (ARIS) to observe the body length, swimming speed, and spatial distribution of untreated (GI group), anesthetized (GII group), and injured (GIII group) T. ovatus in a small offshore cage (1.5 × 1.5 × 2.5 m3). The results demonstrated that the relative error range of the length measurement of the T. ovatus spanned from −3.24 to 4.35, and there was no significant difference between the observed and actual body lengths (ANOVA, p > 0.05). We failed to detect a significant difference in the average speed between the untreated group and the anesthetized group (ANOVA, p > 0.05; Tukey’s HSD, p > 0.05). The injured fish exhibited a significantly lower swimming speed compared to untreated and anesthetized individuals (ANOVA, p < 0.01; Tukey’s HSD, p < 0.01). Untreated individuals and fish with physical injuries exhibited mean vertical distribution depths of 1.06 ± 0.47 m and 1.70 ± 0.51 m, respectively, with the injured fish occupying a significantly greater water depth than the untreated conspecifics (one-way ANOVA, p < 0.01). There was a highly significant association between the treatment status of the fish (untreated/injured) and the frequency of water layer distribution (χ2(2) = 196.78, p < 0.01). The findings of the present study can furnish specific methodological references for the imaging sonar-based monitoring of T. ovatus within aquaculture cage systems. Nevertheless, the study is subject to several inherent limitations, including a small sample size for the injured group (n = 3), the employment of an artificial injury model, and the confinement of experimental subjects to a closed cage environment; these factors may introduce statistical uncertainty and thus exert a considerable impact on the external validity of the study’s results.
Li et al. (Fri,) studied this question.