Rebecca M. Dalton
The timing of biological events in plants and animals, such as migration and reproduction, is shifting as a result of climate change impacts. Shifts in timing of phenological events are often critical for population persistence and may have detrimental effects on population dynamics. Moreover, interacting species may exhibit differential responses and shift at different magnitudes and directions, which can result in asynchronies in food supply and suitable habitat availability. To effectively manage species of conservation concern under climate change, elucidating the occurrence, magnitude and direction of phenological shifts and resulting ecological consequences are high priority. I will be working with Dr. Michelle Staudinger to gain a better understanding of the environmental and ecological drivers and thresholds associated with the timing of spawning migration of alewife, Alosa psuedoherengus, an anadromous fish species of high conservation and cultural concern in the Northeast US.
Biodiversity is critical for essential ecosystem functions and services to humans. Coexistence of many species requires a delicate between inter- and intraspecific competition. This will occur if one species is slightly better at obtaining a specific resources (e.g., acquiring nutrients vs. receiving pollinator visits), but, if changes in conditions due to global climate change or habitat fragmentation occur, this balance could be disturbed and some species to drive others extinct. For example, warming temperatures are causing some flowering species to emerge and reproduce earlier in the season, while others respond to warming temperature by emerging later. If species in a community respond unequally to the same environmental cues, populations might experience higher or lower levels of interspecific competition for shared resources than in the past, which could upset the balance of competition essential for coexistence. I am using a combination of field experiments, observations, and demographic models to examine the relationship between climate, phenology, and species interactions of spring ephemerals. The goal of my research is to understand how species coexistence may change under future climate predictions. I work in the Duke Forest (Durham, NC) with three plant species, Claytonia virginica, Erythronium umbilicatum, and Thalictrum thalictroides and at Rocky Mountain Biological Laboratory (Gothic, CO) with Claytonia lanceolataand Mertensia fusiformis.