Spreading speeds of a Lotka-Volterra predator-prey system: The role of the predator

This paper is concerned with the spreading speeds of a modified Lotka-Volterra predator-prey system; the intention is to describe the propagation mode whereby the two species coinvade a new habitat. Under some assumptions, it is proved that the spreading speed of the prey is slower than in the case where the predator vanishes, and the density of the prey on the coexistence domain is also smaller compared with the case where interspecies actions disappear. Therefore, the predator has a negative effect on the evolution of the prey by slowing the spreading speed and decreasing the population density of the prey.