We investigate the dynamics of stage II retinal waves via a dynamical system model, grounded on biophysics, and analysed with bifurcation theory. We show how the nonlinear cells coupling and bifurcation structure explain how waves start, propagate, interact and stop. Especially, we analyse how the existence of a small region in the parameters space close to bifurcations, where dynamics returns in a recurrent way, give rise to very complex dynamics.