<p>This study presents a prey–predator model incorporating the dual effects of prey vigilance and harvesting under both deterministic and stochastic frameworks. In the deterministic case, the positivity, boundedness,local and global stability of equilibria are analyzed along with the occurrence of Hopf bifurcations. Numerical simulations validate the analytical results and demonstrate how vigilance and harvesting influence population dynamics and system stability for suitable parameter values of the model. Results reveal that moderate vigilance stabilizes the system, while excessive vigilance or harvesting may drive populations to extinction. A sensitivity analysis identifies the parameters exerting the strongest influence on prey and predator densities. The model is further extended to a stochastic framework by adding environmental noise to study its effect on system stability and species persistence. Environmental noise can disturb the system and may destabilize a deterministic system that is otherwise stable. The analysis reveals, as a novel finding, that excessive prey harvesting can lead to the extinction of both species, whereas excessive predator harvesting results in predator extinction, providing important insights for sustainable ecosystem management.</p>