Linking climate, arthropod emergence, and fitness in snow buntings (Plectrophenax nivalis)

Arctic ecosystems are facing some of the most severe and variable climatic impacts due to climate change. We examined the impact of this climatic variation on arthropod abundance and phenology, and how these relationships impact reproductive decisions and fitness in an Arctic-breeding passerine, the snow bunting (Plectrophenax nivalis) using a seven-year dataset from the low Canadian Arctic. Intra- and inter-annual climate-based models yielded significant variation in predictive capacity of arthropod emergence and abundance, limiting their hind- and fore-casting use. At the population level, snow bunting laying decisions appeared constrained by spring temperatures and laying did not appear timed to match nestling peak energy requirements to maximum arthropod availability. However, individual females that timed laying to match peak demand and arthropod abundance had the highest reproductive success, even in low arthropod abundance years. Results highlight the complexities in predicting direct and indirect impacts of climatic variation on Arctic passerine populations