Grant: Discovery Grants Program - Individual

Many biological populations and communities reside in ever changing, dynamic environments, driven by long-term trends in abiotic environmental conditions, such as increasing landscape fragmentation, decreasing habitat quality, or increasing mean temperatures. These trends have negative consequences for some populations, possibly leading to their extinction, and create opportunities for others, possibly leading to range expansions; both can lead to loss of biodiversity and of ecosystem services. We need tools to predict how populations and communities respond to changing environmental conditions in order to successfully manage these systems, adapt and mitigate. The first objective of this proposal is to develop general theory for how populations and communities respond to long-term trends in environmental conditions and for how imminent changes in their dynamics can be detected. Many species live in seasonally varying environments, characterized by recurring patterns of, say, temperature and precipitation, especially in temperate and northern climates and certainly in Canada. Different species have developed different adaptations to these historically predictably recurring conditions, but these conditions change and become increasingly less predictable. Cold seasons become shorter, warm seasons longer, extreme weather events more likely, and temperature patterns exhibit stronger autocorrelation over time. Differential responses of populations to changes in seasonal patterns can lead to changes in interaction networks with other species and alterations to existing community structure. One particular area of great concern in this context are forest insect pests. For example, under historical conditions, budburst of black spruce occurs late relative to the spring development of spruce budworm, so that black spruce is somewhat protected from consumption by budworm and defoliation. Concerns are that budburst of black spruce could advance enough to make it vulnerable to spruce budworm, which could eventually trigger large-scale outbreaks, defoliation and tree death in regions of the boreal forest that have not seen budworm outbreaks historically. The second objective of this proposal is to study specifically the effects of changing seasonal patterns on species interaction. With my diverse and inclusive team of trainees, I will address these challenges through carefully designing mathematical models (hybrid dynamical systems) and developing tools to analyze them and connect them to data. My trainees thrive in my supportive lab and network of collaborators in academia and government. Their integrative training of transferable skills enables them to take up impactful positions in academia, government, and industry to benefit Canadians. The research will enhance our understanding of the effects of climate and land-use change on populations and communities and allow managers to optimize their strategies to preserve biodiversity and ecosystem function.