Changes in within-year population patterns (climate change)

There is a lot of discussion about the ways in which climate change can affect the timing of when a species becomes active in the spring. This had been closely examined in many tree species (monitoring when bud break occurs) and also with bird species (tracking the timing of migration patterns). For insects there is an idea that they need a certain amount of heat to develop. We can measure this with daily temperature if we know the details of the physiological bounds of the insect species. I use historic monitoring data to assess how climate change is affecting the timing of pest insect emergence so we can help farmers anticipate pest population increases in an increasingly stochastic environment.

Between-year population patterns (testing ecological theory)

Ecologists have been interested in population cycles for hundreds of years. Researchers found that lynx (a big cat predator) and hare populations cycle in a way that is offset from each other over decades. It was hypothesized that the specialist predator (lynx) was driving these population booms and busts because of the close association with their prey (hares). Ecologists later found population cycles with moths in forests, however and these species did not have any specialist predators. They hypothesized that tree chemistry was changing to decrease herbivore moth populations when they got too big. Again, historic monitoring of pest populations presents an important source of data to examine these ecological theories in highly disturbed agroecosystems.

Landscape ecology of pest and predator insects

Invertebrates are mobile organisms. As ecologists we are driven to understand how they interact with each other and the environment around them. This drives a desire for mechanistic lab studies, which are excellent. Often, however, the findings from cage studies or plot trials do not scale up to give farmers clear information about what they can expect. As such, it’s important to study mobile organisms on the scale that they interact with the landscape. I study local farm management, landscape homogenization metrics and landscape vegetation phenology to track how insect predator and herbivore communities interact, both directly and indirectly, with their environment.