As climate change effects intensify, key life history events may become decoupled from necessary biotic and abiotic resources. For species of management concern on Department of Defense (DoD) lands, these shifts in phenology may prove difficult to address without a mechanistic understanding of the drivers of phenological shifts. This study will seek to determine the causes and effects of phenological shifts on species of management concern by using observational and experimental data to develop and test population viability models. Specifically, researchers will (i) identify the phenological distribution of adult breeding and juvenile emigration for four pond-breeding salamanders (three of management concern), (ii) determine how shifts in phenology and abiotic resources affect the strength of species interactions, community structure, and population viability, and (iii) provide management options to mitigate shifts in phenology that may impact ongoing conservation and recovery efforts.
This project will use empirical data, downscaled climate projections, and hydrological models to develop population viability models that provide management options under different climate scenarios for three species of management concern on DoD lands. The tasks are as follows: (i) use passive integrated transponder (PIT)-tag technology, drift fences, and egg mass surveys to track the phenology of adult breeding and juvenile emigration movements of pond-breeding salamanders; (ii) conduct mesocosm experiments to test how the timing of transitions between life stages and species interactions affect demographic rates of larval and juvenile salamanders; (iii) determine how shifts in phenology affect aquatic community structure; (iv) use observational data to determine climatic drivers of phenology, and use these parameters along with downscaled climate data to develop simulation models which project phenological shifts under future climate scenarios; (v) use existing site specific hydrology data and downscaled climate data to model climatic drivers of aquatic habitat availability and forecast these conditions under different future climate scenarios; (vi) develop population viability analyses under future climate scenarios using observational and experimental data from this project.
This project will elucidate how projected changes in rainfall patterns and temperatures could affect salamander populations of management concern on and near DoD lands, and will result in models that can be used to guide management decisions about imperiled salamander species. Specifically, this study will improve the mechanistic understanding of how phenological variation will impact both demographic rates and species interactions. Many studies have documented changes in phenology (e.g. advancement in breeding or leaf-out), but empirical tests of the population and community-level effects of such shifts are currently rare. Because researchers include multiple life stages for different species, they will better understand stage-specific responses to shifts in phenology, which have not been examined previously. This approach can serve as a model for both basic ecology and conservation efforts, as researchers will incorporate experimental results into demographic simulation models, which are often not concurrently performed. This project will also benefit the DoD by developing and applying population viability models under potential future climate scenarios -- helping decision makers to understand the range of future possibilities, thereby improving decision-making ability. In addition to creating specific management recommendations for Eglin Air Force Base, Fort Leonard Wood, and St. Marks National Wildlife Refuge, the models developed in this project could be used by natural resource managers of other DoD lands.