A Life Living Atop Others: Investigating Patterns of Diet and Reproduction for a Newly Identified Sabellid at Hydrocarbon Methane Seeps

Dr. Lauren Rice

Postdoctoral Research Fellow, Florida State University

Epibionts, animals that live attached to and on top of living hosts species, are widely observed in marine communities at most latitudes and depths around the world. Despite this commonality, many of these animals and the roles they play within their habitats are understudied. I examined a new species of sabellid feather duster worm, Seepicola viridiplumi, facultatively living atop Acesta file clams at three methane seep systems within the Gulf of Mexico. Using a combination of genetic sequencing, stable isotopes, and paraffin histology, I sought to examine how epibiotic life impacted the trophic ecology, associated microbial community, and reproduction of the sabellid. While all individuals appeared to rely on both chemosynthetic and photosynthetic sources of nutrition, evidence of dietary differences was observed in epibiotic individuals. Additionally, epibiotic individuals consistently had slight increases in egg sizes and fecundity. These findings reveal the potential importance of small-scale spatial changes within seep ecosystems on the biology of epibionts, while simultaneously providing insight into the ecological roles sabellids play in chemosynthetic systems.