Stutzman, R.J., and J.J. Fontaine. 2015. Shorebird migration in the face of climate change: potential shifts in migration phenology and resource availability. Pp. 145–159 in E.M. Wood and J.L. Kellermann (editors), Phenological synchrony and bird migration: changing climate and seasonal resources in North America. Studies in Avian Biology (no. 47), CRC Press, Boca Raton, FL.
Changes in temperature and seasonality resulting from climate change are heterogeneous, potentially altering important sources of natural selection acting on species phenology. Although some species have apparently adapted to climate change, the adaptability of most species remains unknown. Because their life history is dictated by seasonal factors, migratory species may be particularly vulnerable to heterogeneous changes in climate and phenology. Here, we examine the phenology of migratory shorebirds, their habitat, and their primary food resources, and make forecast how climate change may affect migrants through predicted changes in phenology. Daily abundance of shorebirds at stopover sites is correlated with local phenology and peaked immediately prior to peaks in invertebrate food resources in the Prairie Pothole region. A close relationship between migrant and invertebrate phenology indicates that shorebirds may be vulnerable to changes in seasonality driven by climate change. Although it is possible that shifts in migrant and invertebrate phenology will be congruent in magnitude and direction, because migration phenology is dependent on a suite of ecological factors, any response is likely to occur at a larger temporal scale and may lag behind the response of invertebrate food resources. The resulting lack of sufficient access to food at stopover habitats may cause migrants to extend migration and have cascading effects throughout their life-cycle. If the heterogeneous nature of climate change results in uneven changes in phenology between migrants and their prey, it may threaten the long-term viability of migratory populations.