Stability switch and Hopf bifurcation for a diffusive prey-predator system with delay

The increasing time delay usually destabilizes any dynamical system. In this paper we give an example that in some special cases the opposite effect can be experienced if the time delay is sufficiently great. We investigate the effect of both the parameter in the time delay kernel and diffusion coefficient on the stability of the positive steady state for a diffusive prey-predator system with delay. We obtain the condition of the occurrence of the stability switches of the positive steady state.