Impacts of Climate Change on Aquatic Biodiversity in the United States

Climate change represents a widespread and growing threat to aquatic biodiversity with impacts across multiple scales including genes, species, and ecosystems.  An assessment was conducted of the state of knowledge of how climate change has impacted biodiversity, the projected impacts during the coming century, and potential response options policy makers can employ to decrease risk and safeguard our natural assets.  Our key findings suggest that many species are shifting their geographical ranges, distributions and phenologies at faster rates than were previously thought.  Range shifts and novel climates will result in new community assemblages, new associations among species, and promote interactions that have not existed in the past.  Because species and population responses to climate change are highly individualistic, some species will benefit, while others will decline, and possibly go extinct.  Therefore, identifying highly vulnerable species and understanding why they are vulnerable are critical to developing adaptation strategies and reducing biodiversity loss in the coming decades.  In addition, as species shift in space and time in response to climate impacts, effective management and conservation decisions require consideration of future projections as well as historic conditions.  The results of this study were produced by a workgroup on biodiversity, ecosystems, and ecosystem services for the 2013 National Climate Assessment and are intended to provide guidance to natural resource managers and decision makers on critical issues related to climate impacts on biodiversity.