Assessing the state of deep-sea biological knowledge and charting a path for scientific research in Barbados

For Small Island Developing States, including those in the Caribbean, the deep sea remains a challenging ecosystem to study as it requires expensive technology and specialised expertise. The deep-sea environment of Barbados (200-5,776 m) accounts for 99.8% of its Exclusive Economic Zone (EEZ). Barbados is presently in the initial phases of developing a marine spatial plan for its EEZ. Comprehensive baseline information on the deep-sea ecosystems is crucial for evidence-based decision-making. This research assesses the state of deep-sea biological knowledge in Barbados via a comprehensive review of species records from peer-reviewed and grey literature, as well as museum and biodiversity databases. We found 1,589 biological records constituting 309 families and 624 species and morphospecies for Barbados' deep sea. Strikingly, richness analyses estimate that just 20% of the species and 48% of the families inhabiting Barbados' deep sea have been recorded. We also discuss limitations in existing knowledge, including vast geographic areas and depths still requiring research, as well as the varied methods of deep-sea observation and sampling utilised thus far, and the associated influence on the taxonomic composition of the known deep-sea community. Although limited, this assessment of deep-sea biodiversity information has provided insights to assist with the creation of a road map which decision-makers can utilize to guide future management and research activities.