Variation in Phenological Shifts: How do Annual Cycles and Genetic Diversity Constrain or Enable Responses to Climate Change?
Dr. Julie Heath | Boise State University
Effective management of plants and animals requires identifying which species, or populations, may be vulnerable to climate change. To identify vulnerable species, particularly those with the potential to constrain military testing and training, managers need reliable predictive models of whether and how populations may cope or adapt to environmental changes associated with non-stationary climate conditions. Critical knowledge gaps remain, however, about the underlying genetic and environmental factors that affect the potential for populations to undergo phenological shifts in response to climate change. Consequently, researchers and natural resource managers lack biologically realistic tools for testing hypotheses and making predictions about phenology change. This project will address these gaps by accomplishing three objectives. First, researchers will conduct a large-scale investigation of the environmental and genetic factors underlying intra- and inter-annual variation in nesting and migration phenology of American kestrels (Falco sparverius sparverius and F.s. paulus), a species that shows differential responses to climate change across its range. Second, researchers will use empirical data to develop an individual-based simulation model to test hypotheses about mechanisms underlying climate-based phenology shifts. Third, researchers will demonstrate the portability of the annual cycle modeling framework by parameterizing and validating the model for other landbirds. This model will be an important tool for managers to understand how species of concern on Department of Defense (DoD) lands may, or may not, have the adaptive potential to shift the timing of annual cycle events in response to climate change.
This project will add phenology monitoring capacity at DoD installations and build on an existing network of citizen science partners, long-term research programs, and migration monitoring sites to conduct highly efficient broad-scale sampling of American kestrels (AMKE) throughout their annual cycle and across their entire North American range. Researchers will use contemporary genetic approaches and newly-developed miniaturized tracking technology to identify connectivity between breeding, migration, and wintering areas for AMKE. Then they will use regional and local weather variables, genetic composition, vegetation phenology, and migration strategies to explain nesting phenology and productivity. Researchers will use a similar approach to explain spatial and temporal variation in migration phenology and distance. Empirical estimates of relationships among environmental factors, genetics, migration, and phenology will be used to develop SCOPE (Simulation of Carry-Over and Phenological Effects), an individual-based model to test hypotheses about the causes and consequences of phenology shifts in response to climate change over relevant time scales. Once SCOPE is developed researchers will use previously published research and data mining approaches to parameterize the model for DoD Mission-sensitive Species of Concern (DoD Partners in Flight 2016) to demonstrate the usefulness of SCOPE as a portable modeling framework to facilitate research, forecast population responses to climate change, and provide valuable information to meet DoD needs.
This project will advance scientific understanding of environmental and genetic factors underlying phenological shifts. It will be a novel contribution to climate change and phenology research because it will provide a framework for studying phenology across the annual cycle. Importantly, this study will provide a tool that will allow researchers and managers to input information from previous and on-going single-season studies into a full annual- and life-cycle model to forecast change. Adaptive and dynamic models will improve the reliability of predicting which species are vulnerable to climate change compared to current models that assume static climate niches are the best predictor of future species distribution and abundance. Reliable models will make management of DoD species of concern more effective and cost efficient, and support the objectives of the DoD Coordinated Bird Monitoring Plan (Bart et al. 2012) as well as ongoing efforts under the DoD Legacy Program to develop regional and national monitoring strategies for DoD. In addition, this project will be a significant contribution to the monitoring and management of migratory raptors because, unlike most birds that are monitored at breeding sites, raptors are monitored at migration count sites (Rich et al. 2005). As raptor migration strategies change and phenology of migration shifts in response to climate change, migration counts may become unreliable indices of population trends. Therefore, it is crucial that predictive models be developed of how the annual cycle of migratory birds, and raptors specifically, are changing in response to climate change.