Landscape-scale assessments of climate impacts to Gulf of Mexico coastal wetlands

Coastal wetland resource managers along the Gulf of Mexico are often asked the following question: how will climate change affect coastal wetlands and their ability to support fish and wildlife habitat and other important ecosystem goods and services for future generations? Incorporating climatic drivers (i.e., temperature and precipitation) into coastal wetland vulnerability assessments will help coastal wetland scientists and resource managers better address this question. Along the Gulf of Mexico coast, climate greatly influences coastal wetland ecosystem structure and function. The coast spans two relatively dramatic and ecologically-relevant climate gradients: (1) a winter temperature gradient; and (2) a precipitation gradient. Ecologists have long noted that macroclimatic drivers regulate coastal wetland ecosystem types in the region (e.g., mangroves, salt marshes, tidal salt flats). However, quantitative climate-coastal wetland relationships have not been investigated at the regional scale. We used historical climate data (1970-2000), coastal wetland coverage data, and alternative future climate scenarios to develop distribution and abundance models for the region. We identified winter climate-based thresholds that separate mangrove forests from salt marshes. We also identified precipitation-based thresholds that separate vegetated wetlands from non-vegetated wetlands. Our results highlight the importance of incorporating climatic drivers into coastal wetland vulnerability assessments along the Gulf of Mexico and provide information that can be used by resource managers to better prepare for future change and plan restoration and protection efforts accordingly.