The properties of dynamical entanglement of anharmonic stretches in triatomic molecules H2O, O3, C2H2, C2D2, and SO2 are studied in terms of the reduced-density von Neumann entropy with various initial states. It is demonstrated that the maximal entropy of an initial state with local-mode character is smaller than that with normal-mode character. A mean entanglement, defined by average over time, is used to describe the influence of the normal-to-local transition on the behavior of entanglement. It is shown that the mean entanglement exhibits a...