Habitat relationships and effects of protection on a Mediterranean mesophotic reef fish assemblage

The ichthyological community distribution across different habitats and areas with various protection levels in the context of mesophotic reefs shows reliable patterns. In particular, research gaps for MPAs exist in non-rocky habitats, as those regarding seagrass meadows and sedimentary soft bottoms. Fish species assemblages are considered good indicators of MPAs performances (Rojo et al., 2016). Therefore, to obtain a clearer understanding and protect the ecological functions of the mesophotic Mediterranean environment, fish in the infralittoral and circalittoral seascape of Cabo de Palos, Cabo Tiñoso, and Escombreras (area of Cartagena, region of Murcia) were studied. Additionally, the great anthropogenic pressure attributable to the proximity to Cartagena harbor and commercial fishery may address a refuge effect in deeper waters that would enhance the vital importance to the conservation of mesophotic habitats. The project EcoMesoMed integrates different methods (UVC, dropcams, BRUV and ROV, complemented with eDNA) to realize an exhaustive assessment of MPAs effectiveness in the area of Cartagena (Murcia). In particular, this Thesis focuses on the 360°-dropcams technique applied to mesophotic habitats, where both rocky and soft-bottomed environments with different kinds of biological and geological substrates are considered. The chosen methodology also allows the non-invasive sampling of deep and elusive species, often endangered, as well as a precise extime of the commercially important and common ones. This Thesis offers reliable informations about the mesophotic Mediterranean ichtyiological community and distribution in selected areas of Cartagena and Cabo de Palos and look forward to apport its contribution to the development of local conservation and sustainable management strategies.