The benthic communities of the deep insular shelf at the Hind Bank
Marine Conservation District (MCD), an important spawning grouper
aggregation site, were studied with the Seabed autonomous underwater vehicle
(AUV) at depths between 32 to 54 m. Four digital phototransects provided data
on benthic species composition and abundance of the insular shelf off St.
Thomas, U.S. Virgin Islands. Within the western side of the MCD, well
developed coral reefs with 43% mean living coral cover were found. The
Montastrea annularis complex was dominant at all four sites between 33 to 47
m, the depth range where reefs were present. Maximum coral cover found was
70% at depths of 38 to 40 m. Quantitative determinations of sessile-benthic
populations, as well as the presence of motile-megabenthic invertebrates and
algae were obtained. The Seabed AUV provided new quantitative and
descriptive information of a unique coral reef habitat found within this deeper
insular shelf area.