Hurricane Harvey Rapid Response FGBNMS

Hurricanes and other extreme storm events can decimate coral reefs through wave-driven physical damage. Freshwater runoff from extreme storms is also potentially detrimental to reefs but has received comparatively little attention. In August 2017, Hurricane Harvey caused widespread flooding in SE Texas when it released >50 trillion liters of rain, which has since been accumulating along the Texas Shelf. This runoff is expected to impact nearby coral reefs in the Flower Garden Banks National Marine Sanctuary (FGBNMS) via eddies and jets that transport coastal waters offshore. In fact, surface salinity data show that Harvey freshwater recently entered the FGBNMS, lowering salinity from ~36 to ~32 ppt in less than a day. The main goal of this proposal is to characterize the impact of runoff from Harvey on water column chemistry, microbial communities and coral reef invertebrates. The effects of Harvey runoff will be compared to a previously documented storm-driven runoff event that was associated with invertebrate mortality on the same reef system. Sampling seawater chemistry, microbial communities (water column and benthic), and host gene expression before, immediately after, and six months after Harvey runoff enters the FGBNMS will allow us to identify commonalities among large-scale freshwater runoff events and track the response of benthic invertebrate health, microbial community diversity, and the trajectory of reef community recovery or decline. We will investigate if changes in water chemistry induce pelagic microbial shifts, if microbial communities typically associated with corals and sponges are altered, and whether feedbacks occur between these potential drivers of benthic invertebrate mortality.