Stability and bifurcation of a delayed three-level food chain model with Beddington–DeAngelis functional response

A three species food chain model with the Beddington–DeAngelis functional response is analyzed. By choosing the delay ττ as a bifurcation parameter, it is shown that Hopf bifurcation occurs as the delay ττ passes through a sequence of critical values. Numerical simulations are presented for supporting the analytic results.