White area within plots is compacted soil, which contrasts with the darker soil between plots that was plowed just prior to taking this photo. An analysis of movement responses to patch structure at different scales revealed that the biocontrol agent was much more mobile, exhibiting a greater propensity to move within and between landscape plots, than the indigenous coccinellid. If native predators are generally more sensitive to habitat fragmentation than exotic species, our study suggests that we may become increasingly dependent upon the introduction of exotic biocontrol agents that are better able to track pest populations below the biocontrol threshold as agroecosystems become progressively more fragmented. This will obviously incur great ecological, as well as economic, costs. In addition to economic thresholds, there are also ecological thresholds that must be surmounted for successful biocontrol.
Landscape ecology is defined as the study of how spatial pattern affects ecological process.
Thus, this project also demonstrates how landscape ecology can profitably be applied at finer spatial scales to test hypotheses regarding how landscape structure affects predator movement responses to prey distributions, species interactions, and community dynamics.