HANNAH BUDROE

PI: Moira Décima, M.S., Ph.D, Scripps Institution of Oceanography, UCSD Depth-Resolved Patterns in Zooplankton Diversity in Subtropical and Subantarctic Waters: a Size-Structured Metabarcoding Approach

Zooplankton play critical ecological roles in trophic transfer and biogeochemical cycling, and their community composition is closely associated with the physical conditions of their environment. Zooplankton species can often be used as sentinels of oceanographic change, because they can be associated with very specific water masses. In this study, I use a DNA metabarcoding approach, based on 18s rRNA amplicon sequencing, to assess the similarities and variability of community composition in three size fractions (0.2-0.5, 0.5-1, 1-2mm) across depths and water types. The study region sees the mixing of Subantarctic (SA) and Subtropical (ST) waters with distinct physicochemical conditions. Preliminary analysis shows that there are distinct mesozooplankton communities between SA and ST waters. Community composition of the smaller (0.2-1mm) zooplankton is different between epipelagic (200m depth) and mesopelagic environments. This study forms a baseline survey of zooplankton diversity, enabling the detection of Southern Ocean ecosystem shifts in response to climate change.