| Insect spatial phenology models require an understanding of the environmental factors and cues used in development, diapause initiation, and diapause termination. I present a spatial phenology model for grape berry moth that combines these attributes with spatial and temporal environmental heterogeneity. Abiotic and biotic variability can lead to a change in the current paradigm for grape berry moth seasonality, with partial fourth generations possible in grape growing regions along the Great Lakes in the United States and Canada.; Studies of the spatial phenology of a single insect species are logical first steps in understanding the interactions between it and some of the environmental variables that govern its dynamics. However, insects are closely intertwined with other organisms, such as natural enemies, that can also play important roles in population maintenance. Using spatially- and temporally-referenced field data on house flies and a predatory beetle, I developed a mathematical model to address local and regional spatial correlation in prey, predators, and their interaction under different dispersal rates, and endogenous and exogenous factors.; Spatiotemporal analyses of field data revealed that larval fly populations were initially highly spatially structured, but as adult predatory beetles immigrated, the beetles became increasingly clustered at local spatial scales, causing spatial decorrelation in the dynamics of their prey. In this case, the transition from eruptive pest abundance to regulation by a specialist predator was associated with a transition in spatial structuring and dynamics.; I also present theoretical results of the effects of predator and prey dispersal, and nonlinear prey dynamics, on local and regional spatial clustering and cross-correlation. Higher rates of dispersal resulted in greater local spatial clustering for each synthetic species; however, highly mobile predators that attack less mobile prey showed negative local spatial cross-correlation in linearly governed populations. Over local and regional spatial scales, nonlinear, yet nonchaotic, populations can result in synchrony in prey, predators, and their space-time interaction. This work thus shows how in natural enemy-victim systems, synchrony between predators and their prey over local and regional spatial scales can be achieved in locally unstable populations that are linked through dispersal. |
