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Coralligenous reefs are typical underwater seascapes of the Mediterranean Sea and are ranked among the most relevant ecosystems of the basin and a pole of biodiversity. For their critical importance for ecosystems conservation, coralligenous reefs are included among the indicators that should be assessed under the Marine Strategy Framework Directive (MSFD). However, information regarding their spatial distribution and the influence of environmental factors on their structure and biological characteristics is still poor. As part of monitoring regional programs for the implementation of the MSFD in Italy, an extensive study was performed along the Latium continental shelf, aimed to define and map the distribution of coralligenous reefs and to assess their environmental status in three different study areas, characterized by different environmental conditions and subjected to different potential levels of human pressure. For each area, a large dataset was collected, including multibeam bathymetry, side scan sonar records and ROV video transects. The integrated analysis of geophysical data and ROV videos allowed to identify the morpho-acoustic facies indicative of coralligenous outcrops and to map their distribution across the study areas. In parallel, a quantitative analysis of video transects was carried out, in order to characterize the megabenthic communities in terms of species composition, abundance, health status of structural species, and to evaluate the abundance of marine litter. The environmental status of the coralligenous communities was then assessed through the application of the Mesophotic Assemblages Conservation Status (MACS) index. The results obtained showed a large variability in the distribution and characteristics of coralligenous reefs and associated assemblages along the Latium continental shelf, likely reflecting the different environmental conditions and human pressure in the different areas. Coralligenous reefs were reported from all the investigated areas, hosting a rich and varied associated fauna with dense gorgonian forests, also featuring species of relevance for conservation such as Corallium rubrum. The application of MACS index allowed to distinguish among a wide range of ecological conditions of the coralligenous communities, spanning from high to poor environmental status across different sites. The assessment of the extent and diversity of coralligenous assemblages through the combination of geomorphological analysis, acoustic mapping and quantitative video analysis represents an efficient tool, which may help governments and stakeholders making informed management decisions for future coastal planning and conservation strategies.

Since 2007, the non-indigenous calanoid copepod Pseudodiaptomus marinus Sato, 1913 has been increasingly recorded in numerous European sites, spreading at an unexpectedly fast pace over a short time-span. This species presents specific biological and behavioural traits which make it of particular interest for ecological and applied research topics. On 29–30 January 2018, 29 scientists from nine European Countries established the EUROBUS (Towards a EURopean OBservatory of the nonindigenous calanoid copepod Pseudodiaptomus marinUS) Working Group (WG). This WG aimed at creating a European network of institutions and researchers working on the various aspects of the biology and ecology of P. marinus, with an open forum where sharing experience and know-how among WG participants. This brought to an updated distribution map of P. marinus in European waters, as well as to the identification of priority research lines and potential joint initiatives under the WGEUROBUS umbrella. This contribution, stemming from the experts participating at the WG, represents the manifesto of the current and future initiatives developed within WGEUROBUS. info:eu-repo/semantics/publishedVersion

The European Anchovy (Engraulis encrasicolus, Linnaeus, 1758) represents one of the most important fishery resources in some areas of the Mediterranean. This short-lived, small pelagic fish is characterized by large interannual fluctuations, probably as a result of environmental variability. As part of the European Project Med 98-070, the main aim of which was the study of the anchovy population in the Strait of Sicily, icthyoplankton surveys were carried out between 1999 and 2001, during the peak spawning season for anchovy. Present work reports the relationship between meso-zooplankton biomass and the abundance of anchovy eggs and larvae in the Strait of Sicily. Data on anchovy egg abundance showed that the main spawning area was located in the north-western region of the study area. The branch of the Atlantic Ionian Stream, running parallel to the southern Sicilian coast, acts as a transport mechanism for anchovy eggs and larvae towards the southernmost end of the island, off Cape Passero. Observed distributions were largely consistent with local hydrographic features, which allow larvae to be retained in areas providing the necessary feeding conditions for recruitment success.

[1] The present work on mesozooplankton of the Ionian Sea is part of a study aimed at assessing if the epipelagic communities had been affected by the changes in circulation (named EMT, Eastern Mediterranean Transient) observed in the eastern Mediterranean starting from 1988 as a transient effect of climate forcing. A temporal comparison was performed on data obtained in the springs of 1999 and 1992, periods characterized by opposite patterns in the upper circulation that in 1998 reversed from an anticyclonic to a cyclonic flow. A spatial comparison was performed on the data collected in 1999 from areas that previous oceanographic surveys had shown to be diversely affected by the EMT. Interannual differences were observed in the distribution of mesozooplankton abundance in the upper layer that might be related to the EMT dynamics and the effects of the reversed circulation. In 1999, abundance and composition of epipelagic mesozooplankton differed between the northwestern and eastern areas of the Ionian Sea. The distribution of species, trophic groups and copepod gut pigments suggested that different pelagic food webs took place at the opposite sides of the basin. A “classic” type food web prevailed in the northwestern, more productive area, whereas the microbial links prevailed in the eastern, more oligotrophic area. The characteristics of the northwestern area may in large part be due to the enrichment effects of the cyclonic circulation enhanced by the nutricline uprise due to the EMT, and to the interaction between the cyclonic circulation and the continental slope.