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The analysis of 288 samples obtained during 2001-2016 with bottom trawl and epi-benthic sledge between 42 and 900 m depth, has allowed characterizing the benthic communities of the sedimentary bottoms off Cabrera. Up to 328 species/taxa of decapod crustaceans, cephalopod molluscs and nekto-benthic fish collected with trawl, and 496 species/taxa with sledge, mostly crustaceans, algae, molluscs and fish have been registered. This biodiversity is similar, and even higher, to that of other areas of the Balearic Islands. It can be highlighted maërl-forming algae, a protected habitat, introduced algae and other species not reported up to now in the area, as well as the high diversity of sprouts, especially vulnerable to fishing. Three communities have been identified: (i) continental shelf, where algae, echinoderms, ascidians, sponges, mollusks, cephalopods and fish predominate; (ii) shelf break and upper slope, where echinoderms, decapod crustaceans and fish predominate; and (iii) middle slope, with decapods crustaceans and fish; a pattern that coincides with that described throughout the Mediterranean. Nekto-benthic communities have show stability during the last decades, in accordance with the reduction of the bottom trawl fleet exploiting them. These results, most of them obtained by the scientific monitoring program of European fisheries, which allows assessing not only the living resources and the impact of fishing on the ecosystems, but also to study the biodiversity, contribute to improve the scientific knowledge of marine flora and fauna off Cabrera, as a fundamental tool for its management, to make compatible the marine conservation with the sustainability of fisheries. [ABSTRACT FROM AUTHOR]

Spatio-temporal variations of infralittoral fishes in the Cabrera National Park have been studied using the Underwater Visual Census data set from 8 research projects conducted within the period 1993-2016. Among 73 fish species found in Cabrera, the extinction of certain species with north-Atlantic affinity was evidenced, as well as the presence of species with subtropical affinity. There exists a typical Cabrera fish assemblage differing from the fish assemblages of control zones with no protection and characterized by species vulnerable to fishing. Furthermore, there were two distinct depth-related fish assemblages within the infralittoral area; shallow (<15 m) and deep (>15 m). The ecological community descriptors were higher in Cabrera than in Mallorca but followed similar trends in both places. A clear response of the Cabrera fish assemblages to the protection was observed, with a clear recovery during the first 9 years of existence of the park. All indicators dropped from this period on showing similar trends in Cabrera and Mallorca. The cause of these shifts was most likely related to ecological processes with a higher spatial influence such as regional success in juvenile settlement, and also with an indirect effect of protection. The spatial distribution of fish in Cabrera shows a patchy pattern varying between hundreds to thousands of meters and independent of the fishing pressure. Mallorca presented a more homogenous distribution due to the fishing impact. Compared to other Mediterranean reserves, the fish biomass of Cabrera was overall lower except in areas where a greater transfer of pelagic biomass occurred. Continuous biologicalenvironmental monitoring, redesigning of several reserve zones and improving surveillance are key elements to guarantee the fish assemblages in the National Park of Cabrera as being a reference of a good conservation state. [ABSTRACT FROM AUTHOR]