Meeting Abstract
Birds breeding in the Arctic face a short window of time in which conditions favor reproduction. With a limited growing season and harsh weather restricting when nesting habitat and food resources are available, appropriate timing of nesting is thought to be important for reproductive success. The optimal timing of reproduction, however, may vary across years. Additionally, given the rapid pace of climate change in the Arctic, the optimal breeding season may shift dramatically across future decades. Understanding the connection between reproductive timing and reproductive success is critical to evaluating how arctic breeding species will fare as climate change continues to progress. To examine the relationship between spring phenology and reproductive success, we monitored nests in the shrub breeding White-crowned sparrow (Z.l. gambelii) and the open tundra breeding Lapland longspur (Calcarius lapponicus) near Toolik Lake Research Station, Alaska. Data were collected across three breeding seasons with divergent spring phenology from 2012 to 2014. Using a Bayesian statistical approach, we model daily survival rate and examine how nest microhabitat, phenology of food resources, and other factors relate to mortality from different sources including predation and starvation. We evaluate our findings in light of the future changes projected for arctic ecosystems.
