Spatiotemporal dynamics of skeins of wild geese

We performed a spatiotemporal analysis of a one-dimensional array of airborne geese. The one-dimensional structure of individuals exhibits large fluctuations with backward propagation. In field measurements, we measured properties such as the phase velocity, the dispersion relation, and effective interactions. We also proposed a simplified model for nonlinear wave propagation, which is identical to that for highway traffic flow. Our results strongly imply that fluctuations in the array originate from the excitation of collective modes in its intrinsic dynamics.