Abstract
The persistence and recurrence of tar balls causes detrimental effects on coastal wildlife, tourism, and fisheries. Previously, the human pathogen Vibrio vulnificus was detected in marine tar balls in the Gulf of Mexico. Marine tar balls also migrate to low-salt water bodies near the shore. The bacterial communities in tar balls from these environments, however, have not been fully characterized. Herein we describe our studies on the effect of reduced salinity on bacterial communities in marine tar balls. Tar balls collected from the Gulf of Mexico were incubated in deionized water for six months, and their microbial fingerprints were visualized using denaturing gradient gel electrophoresis. Our data show that the indigenous bacterial communities in marine tar balls shifted after being exposed to low-salinity condition. Dominant genera in the tar balls at low salinity were Aquisalimonas and Parvibaculum, neither of which includes known human pathogens.