BELOVSKY 9707564 The control of herbivore populations is a hotly debated issue among ecologists. The PI has been studying the relative importance of weather, food, predators, and history on the regulation of replicated populations of grasshoppers in a grassland ecosystem. This proposal is a renewal of a research project that has continued uninterrupted since 1992. The PI has constructed a general model of population dynamics based on the manner that density affects population processes such as reproduction, probability of predation, and survival. The model employs recruitment curves which relate current population levels to the previous generation. This renewal will continue the experiments began four years ago to further test the PI's initial results that shifts in population dynamics over space and time are predictable. The control of insect herbivores is of paramount interest in an economy emphasizing crop and timber production. This project takes a novel approach in combining density-dependent and independent factors with historical factors to further our understanding of how insect populations are regulated.
