Boldness behavior and ecological adaptability of stone moroko (Pseudorasbora parva) in open-field testing

Boldness is closely related to fish species' adaptative strategies and invasiveness and has become the focus of fish personality research. However, due to the lack of studies on behavioral stages, the ecological functions of certain behaviors remain unclear. To better understand the link between bold-ness and invasiveness in stone moroko (Pseudorasbora parva), an invasive Asian fish species, we exposed the fish to an open-field environment for 60 min and assessed their behavioral patterns, pro-files, and stages. The results show that the boldness behavior of stone moroko was characterized by high activity, low average velocity, and diverse swimming postures. Five behavioral stages with sig-nificant differences were revealed: outbreak, inhibition, slow swimming, exploration, and adaptation. These observations suggest that stone moroko can quickly habituate to new environments. In addition, stone moroko spent more energy on exploring the living area and less on environmental risk assess-ment, as revealed by an analysis of their energy trade-off strategy. The behavioral strategies of stone moroko may explain their extremely high environmental adaptability and ability to invade multiple environments.

Automated summary

Boldness is a significant factor in the adaptative strategies and invasiveness of fish species, particularly in the case of the stone moroko. In this study, the behavioral patterns, profiles, and stages of stone moroko were evaluated in an open-field experiment. The results showed that stone moroko exhibited high activity levels, low average velocity, and diverse swimming postures, indicating a boldness behavior. Five distinct behavioral stages, including outbreak, inhibition, slow swimming, exploration, and adaptation, were identified. These findings suggest that the stone moroko possesses the ability to quickly adapt to new environments.