As the importance of ethology in the management of aquatic animals (including natural resources and aquaculture) becomes increasingly prominent, traditional manual observation and data analysis methods can no longer meet the industry's demand for ethological data of aquatic animals. In recent years, with the rapid development of artificial intelligence (AI) technologies, related technologies have played an increasingly important role in the study on aquatic animal behavior, providing strong technical support for accelerating research on aquatic animal behavior and its application in the fisheries industry, such as aquaculture. This paper briefly reviews the latest applications of AI technology in the study of aquatic animal behavior, and the significant advancement in behavioral research from "manual observation" to "intelligent perception", including automatic image and video analysis, behavior pattern recognition, behavior prediction, and applications in aquaculture. Finally, the review discusses the key research directions of aquatic animal behavior in the AI era, providing a reference for researchers in the related fields. In the future, we should particularly focus on the following fields: ① animal personality which is the core of behavioral ecology; ② behavior-ecology-physiology-gene data chain; ③ AI model generalization; ④ data standardization.