The problem of identifying the sources of switching in the dynamics of nonlinear coupled systems and their mathematical prediction is considered. We study a metapopulation system formed by two oscillating subpopulations coupled by mutual migration. For this model, parametric zones of mono-, bi-, and tri-rhythmicity with the coexistence of regular and chaotic attractors are revealed. The effects of random perturbations in the migration intensity parameter are studied both by methods of statistical analysis of the results of direct numerical simulation and by using the analytical technique of stochastic sensitivity. Noise-induced transitions between anti- and in-phase synchronization modes, as well as between order and chaos, are being studied. Here, the role of transient chaotic attractors and their fractal basins is discussed.