Metabarcoding of zooplankton enhances analyses of connectivity in marine pelagic environments
Dr. Ashrenee Govender*, Dr. Sohana Singh, Prof. Johan Groeneveld, Dr. Sandi Willows-Munro
Oceanographic Research Institute
1 King Shaka Avenue, Point Durban, KwaZulu-Natal, South Africa Pincode: 4001 Mobile: 783844792 E-mail: firstname.lastname@example.org
Zooplankton species composition and relative abundance respond rapidly to environmental variation making them good indicators of ecological change in marine pelagic ecosystems. The objective of this study was to develop and test metabarcoding approaches for zooplankton biomonitoring in the Southwest Indian Ocean. Novel taxon-specific DNA mini-barcodes were designed to increase species identification rates of meroplanktonic taxa, mainly decapod crustaceans and fish. Mock communities with known species composition and relative abundance were used in an experimental setup to test detection rates and the accuracy of designed and published primers. To compare spatial differences in zooplankton assemblages over a narrow continental shelf and bight in eastern South Africa, cross-shelf transects (20 200 m bottom depth) were sampled using plankton tow nets (500 um mesh) at night in surface waters (1-5 m depth). Shelf width, seafloor substrate and benthic habitat structure differed among transects. Metabarcoding of samples detected 186 zooplankton species clusters of which 70.4% could be identified to species level, based on >95% sequence similarity. Malacostraca, Actinopterygii and Copepoda dominated zooplankton assemblages. Zooplankton assemblages from transects within a bight (broad shelf) differed from those over a narrow shelf area and spatial distribution patterns could best be explained by benthic-pelagic coupling and known oceanographic features of the region.