Mapping Community Structure of Canyons and Seamounts of the Northeastern US Atlantic Margin

TitleMapping Community Structure of Canyons and Seamounts of the Northeastern US Atlantic Margin
Publication TypePoster - Conference
AuthorsDijkstra, JA, Mello, K, Malik, MA, Sowers, D, Mayer, LA
Conference Name15th Deep-Sea Biology Symposium
PaginationMonterey Bay, CA
Conference DatesSeptember 9-14

The deep sea communities along the continental margin of the Northeastern United States and the New England Seamount Chain are
biologically diverse systems in which little is known of their distribution and the factors that influence their distribution. In the present study, we examined the distribution and structure of benthic communities along and between ROV tracks and examined relationships between abiotic factors and habitat structure. We analyzed full underwater video footage of 5 canyons and 5 seamounts spanning depths between ~550 m and 2500 m. Tracks were collected by ROV Deep Discoverer during three cruise legs of the 2013-2014 NOAA vessel Okeanos Explorer expeditions along the Atlantic Continental margin. During each dive, a CTD recorded temperature, dissolved oxygen, salinity and depth. We then combined ROV coordinates with CTD, sediment and biological data to map the distribution of benthic communities and their associated environments. To standardize video interpretation, each track was divided into 50 m
longitudinal X 50 cm segments widths and were analyzed for substrate type and organisms. Our findings indicate both coarse and fine-scale difference in community structure between canyons and seamounts, with greater abundance of organisms in canyons and greater evenness and diversity associated to seamounts. Our correlations of abiotic factors and community structure indicate that dissolved oxygen and salinity concentrations were linked to greater evenness and dissolved oxygen concentrations with diversity of organisms for both canyons and seamounts.