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Managing health risks associated with human exposure to waterborne, pathogenic bacteria requires understanding the ecological dynamics of complex bacterial communities. The Hudson River Estuary (HRE) is composed of both freshwater, from tributaries and anthropogenic inputs, and marine water, due to its tidal influence. Vibrio sp., a bacterial genus that includes some pathogenic species, is highly abundant in the coastal ocean, so enters the HRE during high tides. Studies have demonstrated that the viability of particular species of Vibrio is significantly impacted by both light-induced inactivation and ambient temperature. Particle association could impact these rates because microbes attached to particles can benefit from increased nutrients, stability, and protection from UV radiation. Previous research demonstrated that natural populations of Vibrio sp. in the HRE are about 45% particle associated. In this study, we used 16S rRNA gene sequence analysis of isolates to characterize the speciation of Vibrio sp. for free-living vs. particle-associated fractions. Further, to quantify the effect of particle association, we determined light-induced loss and dark, temperature-dependent growth rates for both particle-associated, free-living and total populations of Vibrio sp. using culture-dependent enumeration. We demonstrate that particle association increases temperature-dependent growth and decreases light-induced loss of Vibrio sp.