Analysis of mobile faunal community in the northern Cape Verde throught Autonomous Reef Monitoring Structures

Abstract

The loss of biodiversity and biological invasion phenomena have been prominently shaping studies in marine ecosystems, requiring assertive measures for monitoring and control. Autonomous Reef Monitoring Structures (ARMS) have been demonstrated as eff ective mechanisms for monitoring faunal communities in critical zones in a less invasive way. In this study, ARMS were used for the fi rst time in Cabo Verde to investigate the faunal community in the northewest of Cabo Verde, more specifi cally on the islands of São Vicente and Santo Antão and Birds Islet. The structures were deployed on the seabed for nine months at fi ve strategic points on these two islands and this islet. After the deployment period, the structures were retrieved, mobile organisms were identifi ed, and specifi c diversities at each location were compared. The results showed that the species Trachypollia turricula, Brachycarpus biunguiculatus, and Columbella adansoni were the most abundant and present in all locations. The family Muricidae (Mollusca) was the most representative, and the phylum Arthropoda was the group with the highest number of species, dominating all locations along with Mollusca. Cluster BtA CONGRESO_v5.indd 68 tA CONGRESO_v5.indd 68 13/05/2024 21:17:21 3/05/2024 21:17:21 69 * Corresponding autor: Darilaura Nunes (dnunes@uta.cv) analysis revealed the presence of three groupings in the dataset, and nMDS showed a partial fi t. The ARMS in Marina do Mindelo demonstrated the highest homogeneity compared to other locations studied, unlike those in Porto Novo, which showed the lowest average similarity. The locations that diff ered the most and the least corresponded to Marina with Porto Novo and Ninho do Guincho with Birds Islet, respectively, with Brachyura contributing to dissimilarities. Porto Novo and Birds Islet proved to be the least aff ected by anthropogenic eff ects, as they presented the lowest and highest values of taxonomic diversity, respectively. ARMS proved to be highly eff ective tools for monitoring coastal benthic ecosystems, providing access to a wide variety of species, especially those traditionally diffi cult to reach (cryptic species). Additionally, they generate data that can be compared with those from other l