Addressing data-deficiency of threatened sharks and rays in a highly dynamic coastal ecosystem using environmental DNA

A groundbreaking study reveals that environmental DNA (eDNA) is a highly effective, non-invasive tool for monitoring threatened shark and ray species in dynamic coastal ecosystems. Researchers detected 13 elasmobranch species, including seven threatened ones, from seawater samples in the Bijagós Archipelago, Guinea-Bissau. The approach outperformed conventional fisheries-dependent methods by identifying species not recorded otherwise. Seasonal variations significantly influenced species composition and richness, with notable differences between pre- and post-rainy seasons. Surprisingly, no significant difference was found between protected (MPA) and non-protected areas, suggesting that MPAs may not fully capture the benefits of conservation efforts in such environments. This study underscores the potential of eDNA for biodiversity assessment in data-deficient regions.

Leurs, G., Verkuil, Y. I., Hijner, N., Saalmann, F., Dos Santos, L., Regalla, A., Ledo Pontes, S., Yang, L., Naylor, G. J. P., Olff, H., & Govers, L. L. (2023). Addressing data-deficiency of threatened sharks and rays in a highly dynamic coastal ecosystem using environmental DNA. Ecological Indicators, 154, 110795. https://doi.org/10.1016/j.ecolind.2023.110795