Revealing Hidden Threats: Marine Invertebrate Invasions in the Banc d'Arguin National Park (PNBA), Mauritania, Explored Through DNA Barcoding

The Banc dArguin National Park (PNBA) in Mauritania, a globally significant biodiversity hotspot, faces growing threats from human activities and biological invasions. This study aimed to document marine invertebrate diversity in the PNBA and identify non-native and potentially invasive species. Samples were collected during expeditions in 2021 and 2022, using scuba-diving, drag dredging, and manual intertidal collection across depths of 0 to 20 meters. Through DNA barcoding of COI and 16S genes, 17 species from three phyla--Cnidaria, Bryozoa, and Arthropoda-- were identified, with several cryptic taxa detected. Evidence of human-mediated introduction was found in hydroids (Bougainvillia, Pennaria, Obelia), bryozoans (Amathia, Bugula, Schizoporella), and barnacles (Amphibalanus), suggesting invasions from regions like Brazil, and the Indo-Pacific. Notably, Amathia brasiliensis and Amathia cf. vidovici were recorded for the first time in West Africa, alongside the detection of two other Amathia species, raising concerns about their potential impact on the PNBAs biodiversity and ecosystem services. The presence of these exotic species, likely introduced via international maritime traffic and fishing activities, highlights the parks vulnerability. The study underscores the utility of DNA barcoding for detecting cryptic diversity and tracking species dispersal, recommending urgent conservation measures and biosecurity protocols to protect the PNBAs unique marine ecosystems.