Sara Andreotti1, Kristina Loosen1, Conrad Matthee1
1Stellenbosch University, Botany & Zoology Department, Stellenbosch, South Africa
Biography:
Kristina Loosen studied biological science at the University of Konstanz. She then moved to South Africa to work with great white sharks; first as an intern at Oceans Research and then for her postgraduate degree at the University of Cape Town. Her study investigated abiotic and biotic factors on white shark inshore presence. After a time away from academia, working in an aquarium, as sea turtle biologist in the Maldives and as molecular biologist in a Covid19 laboratory, she started her PhD with Stellenbosch university in 2022 assessing the eDNA metabarcoding methodology for monitoring of chondrichthyan species in South Africa.
Abstract:
South Africa ranks among the top five nations globally in chondrichthyan diversity, with 191 species of sharks, rays, and chimaeras. However, 29% of these species are classified as vulnerable or endangered by the IUCN Red List, highlighting the need for effective conservation efforts. Accurate monitoring of their presence and distribution is essential for informed conservation strategies. Traditionally, monitoring marine species, especially elusive ones like sharks, is challenging, time-consuming, and resource-intensive. Environmental DNA (eDNA) metabarcoding has emerged as a non-invasive, efficient method for species detection, offering a promising solution to these challenges. While eDNA metabarcoding has been applied in other countries, it has not yet been employed for elasmobranch monitoring in South Africa. To test the specificity of our primers, Elas02 (12S) and shark mini barcode (COI), we first collected water samples from a local aquarium, which successfully recovered the elasmobranch species present. Subsequently, we gathered samples from 14 locations along South Africa’s coastline, at both surface and 10-meter depths, to assess elasmobranch species diversity and distribution. Our study aims to compare the recovered diversity with existing records and to analyze the overlap between species presence and current or planned marine protected areas (MPAs). Additionally, we will evaluate diversity indices based on sample depth, habitat types, and proximity to shore. By refining eDNA metabarcoding protocols for South African chondrichthyans, this study provides a baseline for future research, supporting marine monitoring and conservation efforts.