WAVE-TRAINS IN A MODEL OF GYPSY-MOTH POPULATION-DYNAMICS

A recent model of gypsy moth [Lymantria dispar (Lepidoptera: Lymantrii dae)] populations led to the observation of traveling waves in a one-d imensional spatial model. In this work, these waves are studied in mor e detail and their nature investigated. It was observed that when ther e are no spatial effects the model behaves chaotically under certain c onditions. Under the same conditions, when diffusion is allowed, trave ling waves develop. The biomass densities involved in the model, when examined at one point in the spatial domain, are found to correspond t o a limit cycle lying on the surface of the chaotic attractor of the s patially homogeneous model, Also observed are wave trains that have mo dulating maxima, and which when examined at one point in the spatial d omain show a quasiperiodic temporal behavior. This complex behavior is determined to be due to the interaction of the traveling wave and the chaotic background dynamics. (C) 1995 American Institute of Physics.