Segregation is one of the important issues in ecology. Several simple situations have been proposed that enable segregation by using mathematical model approach. In particular, the Lotka-Volterra type three-species reaction-diffusion model is often used, and here we are going to focus on three competing species. Moreover, we consider the situation where an exotic species invades the buffer zone between the native two strong species. Since we already know the existence and stability of traveling wave solution connecting two stable constant states in 2-component strong competition reaction diffusion system, we consider a 3-component extended competition system. The original 2-component traveling wave with no third species is again a trivial solution for the 3-component system as well. We focus on the stability change of this trivial traveling wave solution with respect to the intrinsic growth rate for the third species and study the bifurcation structure around it.

This talk is based on the joint work with Hideo Ikeda, Shin-ichiro Ei and Masayasu Mimura.