Tristan da Silva e Ornelas1,2, Jessica Afonso Ferreira1,2, Teresa Amaro1,2
1Centre for Environmental and Marine Studies (CESAM), Portugal - 2University of Aveiro, Portugal
Mesophotic black coral forests (BCFs) are vital marine ecosystems that provide complex three-dimensional habitats supporting diverse biological communities. However, these ecosystems remain understudied, particularly in the Tropical Atlantic Realm. The BCFs found are dominated by three species, Antipathella wollastoni, Stichopathes luetkenii and Tanacetipathes spinescens. This study investigated benthic and ichthyofaunal diversity associated with BCFs along the coast of Santo Antão, Cabo Verde, across eight locations at depths ranging from 30 to 68.7 meters. We documented benthic and fish communities using photo quadrats (n=240) and video transects (n=38) respectively, to assess biodiversity patterns and community structure. Image analyses revealed 45 benthic species and 53 confirmed fish species across all sites, with considerable spatial variation in community composition. The endemic damselfish Chromis lubbocki dominated fish assemblages across all sites, while benthic communities were characterised by high coverage of rhodoliths, other red algae, and encrusting sponges. Diversity indices and rarefaction analyses indicated varying levels of community complexity among sites, suggesting the influence of local environmental conditions and habitat characteristics. Our findings establish the first comprehensive baseline of BCF-associated biodiversity in Cabo Verde, highlighting these ecosystems as important biodiversity hotspots and emphasizing their significance for marine conservation in the region. This study provides crucial insights for understanding mesophotic ecosystem dynamics and developing effective conservation strategies for these vulnerable marine habitats.
Biography
As a PhD student, Tristan da Silva e Ornelas, focusses on coastal marine ecosystems in Cabo Verde. His research concentrates on the island of Santo Antão where he investigates its coastal biodiversity (<150m) and assesses the trophic ecology of coastal areas. By collecting baseline data on yet unexplored ecosystems his research will recommend conservation strategies which benefit both local economy and the environment.