No abstract

The orange coral Astroides calycularis is internationally protected due to its narrow distribution, its sensitivity to environmental changes and anthropogenic disturbance. Spatio-temporal macrofaunal assemblages associated with A. calycularis were studied along the southern coast of the Iberian Peninsula. A total of 878 invertebrate specimens were collected, comprising 81 species. At the 3 depths studied (0, 5 and 10 m), crustacean species were dominant in terms of abundance, followed by annelids and molluscs. Macrofaunal densities were higher in October and May, and lower in August and September. Janira maculosa (isopod), Lembos spp. (gammarid) and Stenothoe cavimana (gammarid) were the most abundant species, present in almost all depths and months. ANOVA analyses by month reflected significant differences in species richness and Shannon-Wiener diversity, but no differences among depth ranges and no interaction between time and depth. PERMANOVA analyses showed significant differences in the associated macrofauna for time and depth, but no interaction was observed between these factors. These results indicate the ecological relevance of this Mediterranean scleractinian coral as a habitat for many macrofaunal groups. Furthermore, the conservation of this endangered species contributes to the preservation of high marine biodiversity.

Human activities have increasingly affected biodiversity in the Mediterranean Sea. Data on the distribution and abundance of species allows researchers to assess the possible degradation of wild populations. These data could act as a baseline to assess the magnitude of the effects of human activities on a bioindicator species. The distribution and relative abundance of the south-western populations of the endemic Astroides calycularis in the South Iberian Peninsula were studied to establish a baseline for future studies. The rocky shoreline was studied at a depth range of 0–12 m, including more than 650 km of Spain's Andalusian coastline. The species was present in 135 of the 585 dive points sampled. ANOVA analysis showed differences in depth in the four provinces studied, and there was no interaction between the two factors. As human activities on the Mediterranean coast are reducing the A. calycularis populations, a baseline on marine populations is greatly recommended for monitoring, assessment, and management studies, especially for endangered or bioindicator species. This baseline could be useful as a reference tool to assess the effects of human activities on marine biodiversity, including global change.

The endangered and Mediterranean endemic orange coral (Astroides calycularis) hosts an important macrofaunal assemblage. The gut contents of the main peracarids associated with the orange coral were analysed. In total 161 specimens belonging to 11 species and 9 families were examined on the southern coast of the Iberian Peninsula. The gut content study was carried out introducing the specimens of each species in Hertwig's liquid. The analysis revealed that the peracarid species associated with A. calycularis had different feeding strategies and their main food source was detritus. The results highlight that peracarids may depend on the host and the detritus that the coral produces.

The increasing human impact at shallow depths may be affecting the Mediterranean endemic coral Astroides calycularis irreversibly. Therefore, management tools need to be developed for use in its conservation. The main aim of this study was to test a reliable attachment methodology for restoring sites where the species has been affected by human activities. We chose an attachment technique using a marine quick-action epoxy resin, completing three treatments (control, transplanted and translocated colonies) in two sites with different hydrodynamic conditions. Control colonies were undisturbed colonies that were not manipulated; translocation colonies were dislodged and reattached in the same place; and transplantation colonies were dislodged and attached in a different area. Translocated colonies showed a higher survival than transplanted ones, and survival was also higher in environments with more hydrodynamism. Regarding growth, Analysis of Variance (ANOVA) did not show significant differences among treatments, but significant differences between areas with different hydrodynamic conditions were noted. This study confirms that it is possible to transplant or translocate colonies of this coral with the technique proposed here, which could be used in future management plans for areas impacted by humans.