Relationship between foraging behavior and predatory gain of Neoseiulus bicaudus under different prey densities

• Prey density affects the foraging behavior frequency of Neoseiulus bicaudus . • Machine learning algorithms were used to classify the movement states of Neoseiulus bicaudus into active state and inactive state. • The inactive state is a key factor influencing the predatory efficiency of Neoseiulus bicaudus . • The foraging behavior of Neoseiulus bicaudus aligns with predictions from optimal foraging theory. • Energy gain significantly influences the inactive state of Neoseiulus bicaudus . Foraging behavior determines natural enemies’ predation capacity and biological control efficacy. Prey density significantly affects their foraging behavior. Studying predator foraging under different prey densities with movement process analysis reveals foraging mechanisms through energy investment and return. The predatory mite Neoseiulus bicaudus (Wainstein) (Acari: Phytoseiidae) preys on pests including Tetranychus turkestani Ugarov et Nikolskii (Acari: Tetranychidae). Using video-tracking, we evaluated how T. turkestani densities (0, 1, 5, 10, 20, 30 per arena) affect N. bicaudus foraging behavior, movement, and energy gain. This research investigates behavioral mechanisms underlying prey density effects on predation capacity and evaluates biocontrol optimization from a behavioral perspective. Prey density significantly impacted N. bicaudus foraging, with attack frequency peaking at 30 prey. Time allocation among behaviors remained constant across densities. Movement analysis using machine learning algorithms (based on speed and turning angle parameters) revealed two distinct movement states: active and inactive. Below 10 prey, inactive states dominated; higher densities favored active states. Inactive states significantly affected attack frequency and prey consumption; predation rates were further modulated by movement states interactions. Energy gain correlated significantly with inactive-state duration. High prey densities decreased per-prey feeding duration but increased total energy gain and extended patch residence time. Neoseiulus bicaudus dynamically regulates predation frequency and locomotor states in response to prey density. Movement states may be the key factor influencing predation efficiency, consistent with optimal foraging theory predictions. This mechanistic understanding of predator–prey interactions provides a framework for optimizing natural enemy-based biocontrol strategies.