Black corals (order Antipatharia) are important components of mesophotic and deep-water marine communities but due to their inaccessibility, there is limited knowledge about some basic aspects of their ecology and distribution. The aim of this thesis was to test methodologies to map and study a branched antipatharian species, Antipathella wollastoni, in the Canary Islands. Acoustic tools, Side Scan Sonar (SSS) and Multibeam Echosounder (MBES), coupled with ground-truthing video surveys were deployed to map the black coral gardens and to describe their physical characteristics. Closed-circuit technical diving was used to survey A. wollastonipopulation density and colony sizes. Results revealed that SSS and MBES can provide a comprehensive description of species’ physical habitat showing preference for deeper waters, steep west-facing slopes with rocky substrate. However, the acoustic tools were unsuccessful in mapping the antipatharian distribution. The closed-circuit diving was effective in surveying A. wollastonipopulation structure. The data constitute a first quantitative information about this species densities and a first record from the Canarian archipelago about its colony sizes, showing densities between 0.5 and 2 colonies/m2, colony sizes between 80 and 130 cm and a positive bathymetrical gradient for both life traits. Limitations and future improvements of the methodologies are discussed.
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