Behavioral Analysis of Stocked Fish Using Individual-Based Model

This study pioneers an individual-based model (IBM) integrating behavioral movement, bioenergetics, and mortality mechanisms to simulate downstream migration of hatchery-released Acipenser sinensis subadults in large river systems. The model innovatively couples hydraulic drivers with individual physiological responses, enabling high-resolution prediction of spatiotemporal distribution and survival dynamics beyond acoustic monitoring limitations. Results demonstrate the model’s capability to: (1) Quantify flow-dependent migration speed variations, (2) Reveal linear energetic depletion patterns during non-feeding migration, and (3) Identify incidental mortality (e.g., anthropogenic threats) as the dominant survival constraint, overriding starvation risks under natural metabolic regimes. Validation against field tracking data confirms model robustness across river reaches. This framework provides a transformative tool for evaluating stocking efficacy, designing river protection infrastructures, and optimizing release strategies for endangered migratory fishes in regulated rivers.