Trophic control of the ranchman’s tiger moth (Platyprepia virginalis) across a moisture gradient

Determining the factors controlling herbivore abundance and distribution has preoccupied ecologists since the inception of the field. Though once hotly debated, most researchers now agree that resource limitation (bottom-up) and predation (top-down) interact to regulate populations. A new focus is understanding spatiotemporal variation in trophic structure. We studied the effects of bottom-up and top-down control on a chewing herbivore across habitat types and multiple life-stages. Our results indicate that the strength of trophic control is spatially and temporally dependent. Revealing such complexities has important implications for population dynamic models and spatial ecology.