This study tests the hypothesis that, independent of feeding mode, sponges have adapted to a peripheral vent habitat through association with chemoautotrophic microbes. We used a combination of molecular tools and stable isotope analysis to test this hypothesis. Phylogenetic analyses were used to assess relatedness to known sponges with chemosynthetic microbial symbionts, sponge microbiomes were examined to determine if the sponges were associating with vent-specific microbes, and finally stable isotope measurements were used to explore sponge nutritional sources.