This research project seeks to linking microbial communities or types to specific environmental conditions through repeated observations in a temperate, coastal ecosystem (Pivers Island Coastal Observatory: PICO) located at the Beaufort Inlet, Beaufort NC USA. By comparing particle-associated and free-living bacterial diversity at this coastal location over the course of 14 months, we show that bacteria associated with particles are generally more diverse and appear to be less responsive to commonly measured environmental variables than free-living bacteria. These diverse and highly variable particle-associated communities are likely driven by differences in particle substrates both within the water column at a single time point and due to seasonal changes over the course of the year. Further research on the changing microbes present over time, in this case three years of weekly monitoring, has revealed novel patterns in the microbial community. As in other locations, the microbial community at PICO changes in repeated patterns over the course of a year. However, these community changes are largely due to the dominance of specific types in either the summer or winter along with some groups that are present year-round. Rapid transitions between summer and winter microbial communities appear to be linked to the large (20 ?C) temperature change at this site over the course of a year. Overall, this research provides insight into how the environment shapes the microbial community in the coastal ocean. Last Modified: 12/04/2016 Submitted by: Dana E Hunt