Objective

Long-term management and restoration of southeastern coastal ecosystems, and the threatened, endangered, and at-risk species that occupy them, may be limited by the cumulative effects of climate change on already stressed systems. Coastlines along the northern Gulf of Mexico and other low-lying coastlines will be directly impacted by sea-level rise and increases in storm activity, with associated alterations to coastal habitat. Coastal species may cope with these environmental changes over the short term, but eventually they will be eliminated unless migration and establishment at landward locations occur. These processes depend on the ability of species to reach and to colonize environmentally suitable areas. Mechanisms by which shifts in species distributions occur are poorly understood, and current models do not adequately address the role of tropical storms, despite projections that they will intensify in this region. Long-term sustainability of these coastal assemblages will require provision of suitable habitat to which species can disperse and colonize as their habitat envelopes shift inland. When species responses are delayed or suitable habitat is lacking or fragmented, assisted migration and restoration of degraded inland habitat may be necessary.

The primary objective of this project is to test the effects of shifting tropical storm regimes on coastal ecosystem disassembly and reassembly in the context of climate change and its effects on sea-level rise and storm surge. Previous research indicates differential ability of coastal species to persist in situ and/or migrate inland. For some species, assisted migration may be necessary to persist in the system. Successful colonization may require removal of upslope vegetation, as well as movement of propagules into more suitable habitat to overcome dispersal limitation. In this project, researchers will assess mechanisms of coastal species migrations in response to climate change-driven shifts in disturbance regimes.