Changes in insect population dynamics due to climate change

Abstract Climate change can modify the population dynamics of insects. In this instance, “climate” encompasses temperature and precipitation patterns, including dry season or snow cover duration and timing. Also included are changes in both climate means and variances. Insect declines in response to climate change are real but population dynamics are heterogeneous across space and taxa. Both rates of climate change and the location of a population within its climate envelope affect the outcome. Our understanding is currently limited by five factors. First, insect monitoring studies cover a narrow geographic range. Second, other anthropogenic changes, such as land-use change, jointly affect the results of climate change on insect dynamics. Third, species interactions may be affected by climate change, with resulting indirect effects on insect dynamics. Fourth, our understanding of the underlying physiological and fitness response to weather extremes is still limited for insects. Fifth, we have an insufficient understanding of the dynamics of changes in vital rates, which control population dynamics, in response to climate change. This chapter examines these factors, with an emphasis on temperate and arctic species.