Preliminary assessment of the effects of bottom depth and distance from shore on a shallow water pelagic community in the Eastern Tropical Pacific

HCNSO Guy Harvey Oceanographic Center Nova Southeastern University

Species diversity and community structure in much of the pelagic zone remains poorly studied. This includes a lack of understanding of how seafloor depth and distance from shore drive community compositional change. Understanding the factors that influence community composition and dynamics is important for planning effective ecosystem-level management, and especially so in heavily exploited areas such as the Eastern Tropical Pacific where illegal, unreported, and unmanaged fishing is common. Here, we use a non-invasive sampling technique, midwater baited remote underwater video surveys, to describe an Eastern Tropical Pacific shallow water pelagic community in the waters off the Tropic Star Lodge, Pinas Bay, Southern Panama. To date, we have completed camera drops at 50 sites, split between two survey depths, 10 and 40 m. Currently, 47 h of video have been analyzed from 25 sites at 10 m depth. From this video we have identified 315 individuals from 10 distinct taxonomic units. Five species of teleost fishes and two species of sharks were identifiable to the species level, while a sea turtle, a ray, and several assemblages of juvenile pelagic fishes were identified to the family level or higher. Although only a subset of the video surveys has been examined, results suggest the video surveys captured most of the megafaunal species in this system. Analysis of the 300 hours of video collected in 2019 is ongoing, with surveys planned for another 50 pelagic sites during 2020.