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The reticulated leatherjacket Stephanolepis diaspros and the Por's goatfish Upeneus pori occur as lessepsian migrants in the eastern and central Mediterranean Sea. This article reports on the findings of one reticulated leatherjacket and two Por's goatfishes in the Gulf of Castellammare, southern Tyrrhenian Sea, which suggest a possible westbound expansion of the Mediterranean distribution for the latter species. The specimens were three adults collected by professional fishermen on inshore sandy bottoms with a trammel net. The main meristic characteristics of both species, the identification issues of S. diaspros, and the potential impact of U. pori on the native biota and artisanal fisheries are briefly discussed. [ABSTRACT FROM AUTHOR]

Fishing has significant trophodynamic impacts on marine communities, including reductions in the mean trophic position (TP) of the ecosystem resulting from a decrease in the abundance and size of species and individuals with high TPs. This study demonstrates the erosion of fish TP, an additional process that results in lower TP of individuals of a given size, which may exacerbate the effects of fishing on the food web. A stable isotope approach based on the tRophicPosition Bayesian method was used to quantify the TP of 12 target marine species at a given length, and compare their TP between fishery-restricted areas and trawled areas. The results show a difference in the TP of six benthic and apical nekto-benthic predators, which feed in the median at about 0.5 TP lower in trawled areas. It appears that current 'fishing down marine food webs' analyses may underestimate the trophic effects of fishing. Accounting for changes in trophodynamics of individuals at a given size is important to detect indirect effects through food web interactions. The application of a trawling ban may lead to the restoration of lost trophic structure; however, trophic changes may occur more slowly than changes in biomass. This article is part of the theme issue 'Connected interactions: enriching food web research by spatial and social interactions'. [ABSTRACT FROM AUTHOR]

The collection of Crustacea preserved in the Museum of Zoology "P. Doderlein" in Palermo (Italy) has been revised in the framework of the activities of the National Biodiversity Future Center. The main part of the collection is composed of Decapoda, while a smaller part includes Stomatopoda, Isopoda, Amphipoda, and Cirripedia. Overall the collection includes common species, some of which are now protected. [ABSTRACT FROM AUTHOR]

This paper reports the results of a 15-year trawl ban imposed in 1990 in the Gulf of Castellammare (GCAST: NW Sicily, central Mediterranean Sea) and its effects on the biomass and size structure of demersal finfish and shellfish and on the proportion of different commercial categories of fish. Data were collected by experimental trawl surveys conducted in the GCAST and in two trawled areas before and after 1990. The biomass of the total assemblage and of a number of selected species was significantly higher in the GCAST after the ban. Highly commercial species had the largest increase in the same gulf after the ban, particularly at the depths used by artisanal fishermen. The results from size-based indicators were not as clear-cut as those from biomass though. Although the length frequency distributions obtained in the GCAST were significantly different from the other gulfs, in several cases, the values of the size indicators were higher in the trawled gulfs. Our results suggest that, at the temporal and spatial scale adopted, trawl bans may drive full biomass recovery but only partial size structure recovery of the fish populations subject to trawl exclusion, at least in the Mediterranean. The trawl ban in the Gulf of Castellammare provides an example of an effective ecosystem-based fisheries management tool that offers the potential for fish stock rebuilding and for the economic sustainability of artisanal, small-scale fisheries. [ABSTRACT FROM AUTHOR]

The white seabream Diplodus sargus (L., 1758) (Osteichthyes, Sparidae) is a littoral species living mainly in rocky habitats and distributed in the eastern Atlantic and the Mediterranean. This species is targeted by artisanal and recreational fisheries and presents a high commercial importance. Although classified by IUCN as a "least concern" species, it has been the object of marine ranching and restocking initiatives to counteract locally intense exploitation. Here, we review the current knowledge on the movement ecology of white seabream given the relevance of animal movement in ecological and behavioral studies and their potential application in management and conservation. The literature on this topic was analyzed in order to summarize the results of past research and to identify the gaps that still exist on the matter. We reviewed a total of 27 papers focusing on the movement ecology of white seabream, where acoustic telemetry (n = 12), underwater visual observation and traditional tagging (n = 6), genetic analysis (n = 6), and otolith microchemistry (n = 3) were used. While the first three methods were applied to juvenile and adult fish, the last one was also used with larvae, which have been the object of experimental trials to ascertain their swimming abilities. The largest amount of information on activity rhythms (diurnal with a few exceptions), movement patterns (short distances), homing (ability to come back to the capture site), site fidelity (high), and home range (< 200 ha on average and highly related with seabed morphology) were obtained through acoustic telemetry, whose main limitation is the minimum body size required for its application. The environmental variables found to affect movement patterns in this species are water temperature (which triggers spawning-based vertical movements), local sea conditions (which affect short-scale movements in juveniles), and the main seabed features (orientation and habitat type). The main gaps identified, which need more extensive research and some technological improvements, include the study of the effects of environmental variables on fish movements and further investigations on the movement patterns of juveniles. [ABSTRACT FROM AUTHOR]

Four individuals of the non-indigenous blue crab, Callinectes sapidus Rathbun, 1896 (Crustacea, Decapoda, Portunidae) were collected during commercial trammel net operations in fall 2019 and winter 2020 along the coast of NW Sicily. The crabs were collected in very shallow waters on a sandy bottom close to the coast. Although blue crabs are now widespread along most eastern, western and northern Mediterranean coasts, this is the first record of this species from the central and southern Tyrrhenian Sea. [ABSTRACT FROM AUTHOR]

Benthic—pelagic coupling plays a pivotal role in aquatic ecosystems but the effects of fishery driven interactions on its functioning has been largely overlooked. Disentangling the benthic—pelagic links including effects of mixed fisheries, however, needs sketching a whole description of ecosystem interactions using quantitative tools. A holistic food web model has been here developed in order to understand the interplay between the benthic-pelagic coupling and mixed fisheries in a Mediterranean system such as the Strait of Sicily. The reconstruction of the food web required review and integration of a vast set of local and regional biological information from bacteria to large pelagic species that were aggregated into 72 functional groups. Fisheries were described by 18 fleet segments resulting from combination of fishing gears and fishing vessel size. The input-output analysis on the food web of energy pathways allowed identifying effects of biological and fishery components. Results showed that the structure of the Strait of Sicily food web is complex. Similarly to other Mediterranean areas, the food web of the Strait of Sicily encompasses 4.5 trophic levels (TLs) with the highest TLs reached by bluefin tuna, swordfish and large hake and largely impacted by bottom trawling and large longline. Importantly, benthic-pelagic coupling is affected by direct and indirect impacts among groups of species, fleets and fleets-species through the whole trophic spectrum of the food web. Moreover, functional groups able to move on large spatial scales or life history of which is spent between shelf and slope domains play a key role in linking subsystems together and mediate interactions in the Mediterranean mixed fisheries. [ABSTRACT FROM AUTHOR]

Two specimens of the uncommon calappid crab Calappa tuerkayana Pastore, 1995 are reported from the central Mediterranean. One juvenile individual was caught in a trawl net at about 105 m depth on a detritus bottom, and one adult male was caught in a trammel net at 50 m depth in a similar habitat. Details about carapace ornamentation and fresh color of the adult, which complement previous descriptions are provided. Family Calappidae includes four species in the Mediterranean Sea. C. tuerkayana has been recorded a few times from its known geographic range. These are the southernmost records to date. [ABSTRACT FROM AUTHOR]

This paper presents the results of the application of an ultrasonic telemetry system to the investigation of short-term movements in the European spiny lobster, Palinurus elephas, in a coastal area of NW Sicily (Central Mediterranean Sea). Ten lobsters were tagged with miniaturized transmitters and released over a favourable habitat and their movements then recorded by means of nine automated receivers with the objective of investigating post-release displacement, home-range extension, movement patterns, activity rhythm and the influence of lunar light intensity on lobster activity. Acoustic detection data were used to assess activity and home range using estimates of horizontal and vertical movements and minimum convex polygons, respectively. Continuous wavelet transform ( CWT) analysis was applied to time series of position data. Acoustic data from five of 10 lobsters were successfully recorded across a 78-day study period between April and June 2008. All of them displayed an activity pattern characterized by diurnal sheltering and nocturnal foraging, with higher activity (i.e., longer distances travelled) at night. Their home range measured between 1629 and 8641 m2, and all lobsters relocated every 4.6 days on average, probably in search of unexploited feeding grounds. For this reason we hypothesize a nomadic movement pattern for our tagged lobsters. CWT analyses highlighted a 24-h periodicity in lobster activity, with higher activity from sunset to sunrise. No clear influence of moon phase on lobster activity was detected. [ABSTRACT FROM AUTHOR]

Fishing has been important in the Mediterranean region for many centuries and still has a central role in its economic importance and cultural heritage. A multitude of fishery-oriented marine managed areas have been implemented under a highly complex political and legislative framework to protect fishery resources and sensitive habitats from high impact uses. However, a review of the literature revealed that few data are available to support their effectiveness, except for a few studies on fishery reserves and marine reserves. In these cases, fish biomass has increased and some evidence of ecological and socioeconomic benefits has been documented. The environmental and geopolitical complexity of the Mediterranean region as well as the dominant top-down management approaches, constitute the weakest points in the spatial management of fisheries at regional level. A coordinating role of all national and supranational bodies present in the area is desirable in the near future. [ABSTRACT FROM AUTHOR]

This manuscript is an outcome of the workshop entitled “Scientific Strategy for a Global Approach to Promote Regional Ecosystem-based Approach to Fisheries (EAF) in the Mediterranean and Black Seas” held in Sète (France) in July 2012. The workshop was organized by Work-Package 6 of the coordination action “Coordinating Research in Support to Application of Ecosystem Approach to Fisheries and Management Advice in the Mediterranean and Black Seas” (CREAM), funded by the EU Seventh Framework Programme. The main aim of the workshop was to discuss what is needed to advance on a robust scientific strategy to promote EAF in the Mediterranean and Black Seas. Participants discussed a series of scientific recommendations for promoting the coordination of initiatives with the aim of contributing to an operational EAF. Discussion was carried out on (i) what can be learnt from case studies that promote EAF worldwide, (ii) how a scientific strategy for EAF can be built, and (iii) which are the future scientific networking activities to promote EAF. Here we summarize the discussions and conclusions of the workshop, and we present the recommendations and future initiatives proposed to advance EAF in the Mediterranean and Black Seas region. Participants to the workshop agreed that the achievement of a common vision regarding the Mediterranean and Black Seas region should be one of the first and most important elements towards a successful EAF. A common vision should recognise the need to promote the reconciliation of conservation and exploitation, and to aim for a good socioeconomic and ecological status. The vision should also promote the recovery of ecosystems and rebuilding of marine commercial stocks and predator species. EAF initiatives, carried out worldwide, illustrated that whilst the development of relevant science is essential to render the EAF process operational, the involvement of stakeholders is the key factor that characterises successful initiatives. This is especially important in the Mediterranean and Black Sea context, where many stakeholders show conflicting interests and associated trade-offs. During the workshop, it became clear that numerous overlapping and poorly coordinated initiatives for EAF exist in the region. The group discussed the integration of the existing initiatives in a coordinated manner and arrived to the conclusion that a scientific network to promote coordinated and operational EAF initiatives created by the scientific community is needed. Ultimately, the discussion was focused on how to build such a scientific network and how to proceed to consolidate the regional scientific vision, with a clear scientific strategy and roadmap, including a diversified toolbox. In the short term, the proposed EAF scientific network should (i) document and coordinate scientific initiatives, (ii) promote the sharing of scientific information and capabilities, (iii) promote data availability, integration, harmonization, and interoperability, (iv) promote training capabilities and capacity building of the scientific community and stakeholders, (v) establish mechanisms to disseminate knowledge, and communicate EAF benefits, and (vi) promote concrete regional scientific initiatives. In the long run, the network should promote scientific advice on EAF to inform adaptive management, and promote EAF implementation at different geographical scales (from local to regional) using a transversal approach. The ultimate goal of the network should be to link management advice to good scientific information providing useful advice to address management objectives (i.e. present the trade-offs), and creating a knowledge-based management approach. [ABSTRACT FROM AUTHOR]

Sweeting, C. J., Badalamenti, F., D'Anna, G., Pipitone, C., and Polunin, N. V. C. 2009. Steeper biomass spectra of demersal fish communities after trawler exclusion in Sicily. – ICES Journal of Marine Science, 66: 195–202. The effects of trawling on Mediterranean demersal fish communities were assessed by comparing them with the normalized biomass spectra among three gulfs on the north Sicilian coast, one of which had been subject to 15 years of trawler exclusion. Comparisons were conducted across seasons and among depth strata. Biomass-spectra slopes were significantly steeper in the gulf that was closed to trawling than in the unprotected gulfs. This was attributed to the exclusion of trawlers, which lacked catch-size selectivity, and to the continued fishing by artisanal gears that are more size selective. The biomass of all size classes was higher in the protected gulf than in unprotected areas, and increases were greatest in smaller size classes. Community mean individual fish mass was similar among all areas with a wider range of body masses present in the trawl exclusion area, compensating for the greater abundance of small fish. Size-spectra slopes were generally shallower and midpoint heights lower with increasing depth and were greater in autumn than spring; the effect of these seasonal and depth factors was as great as that of protection. Depth patterns are explainable by bathymetric trends in within- and among-species fish size. Seasonal differences were attributed to variation in spawning behaviour and fishery recruitment, with seasonal differences being greater in unprotected locations as a result of recruitment overfishing. [ABSTRACT FROM PUBLISHER]

The stomachs of 427 giant red shrimps, Aristaeomorpha foliacea, caught in the Strait of Sicily (Mediterranean Sea) during four seasonal surveys contained 73 cephalopods, or 8·6% of prey. Cephalopods ranked third as prey following crustaceans (49·2% of prey) and bony fish (20·5% of prey). The following cephalopod taxa were identified: Heteroteuthis dispar, Sepietta oweniana, Brachioteuthis sp., Abraliopsis morisii, Onychoteuthis banksii, Ancistroteuthis lichtensteinii, Histioteuthis bonnellii, H. reversa, Taoniinae sp., Octopodidae sp.; the dominant species was Heteroteuthis dispar (13 specimens). All remains pertained to small and very small specimens, including early juveniles; rostral length of 13 beaks (=17·8% of cephalopods) measured <1 mm. Early juveniles were found in stomach contents only in summer and winter. Cephalopod size was found to be positively correlated to shrimp size. No seasonal nor predator sex-related differences were found in the quantities and frequencies of ingested cephalopods. [ABSTRACT FROM PUBLISHER]

Anthropogenic impacts on Posidonia oceanica meadows have led to a decline of this ecosystem throughout the Mediterranean. Transplantations have often been prescribed as a compensation measure to mitigate the impacts caused by coastal maritime works. Here a Q methodology approach was used to investigate the stakeholders' attitudes in four case studies of P. oceanica transplants realized in Italian waters. Twenty-two respondents were asked to score 37 statements, and the resultant Q-sorting was analyzed via an inverse PCA using the KADE software. Four discourses, corresponding to the significant axes in the factorial analysis were identified: science and conservation (F1), oriented at a rigorous scientific approach; engineering and industry (F2), oriented at the economic development; environmentalism and participation (F3), oriented at the conservation of seagrass meadows; and transplantation-oriented (F4), oriented at the realization of transplants as compensation measures. The main conflicts and agreements between discourses are assessed and discussed, based on the analysis of the distinguishing statements that contributed to consensus or disagreement among discourses. The benefits of the Q methodology in the identification and mediation of conflicts in the four case studies are discussed, and its potential as a powerful aid in the development of a good environmental governance is acknowledged. [ABSTRACT FROM AUTHOR]

Marine protected areas (MPAs) represent the main tool for halting the loss of marine biodiversity. However, there is increasing evidence concerning their limited capacity to reduce or eliminate some threats even within their own boundaries. Here, we analysed a Europe-wide dataset comprising 31,579 threats recorded in 1692 sites of the European Union's Natura 2000 conservation network. Focusing specifically on threats related to marine species and habitats, we found that fishing and outdoor activities were the most widespread threats reported within MPA boundaries, although some spatial heterogeneity in the distribution of threats was apparent. Our results clearly demonstrate the need to reconsider current management plans, standardise monitoring approaches and reporting, refine present threat assessments and improve knowledge of their spatial patterns within and outside MPAs in order to improve conservation capacity and outcomes. Unlabelled Image • Recreational activities and fishing are the main threats affecting European MPAs. • The majority of the threats occur/act both inside and outside the boundaries of the MPAs. • There is heterogeneity in the distribution of threats across European countries. • Standardised monitoring and assessments are needed to improve conservation capacity and outcomes. [ABSTRACT FROM AUTHOR]

Highlights • We show that the white grouper and the black-bellied anglerfish are the most important predators of the red mullet in Mediterranean areas. • We show how predators of an important demersal target species (Mullus barbatus) can increase after a decadal trawling ban. • Our results show a potential re-establishment of the trophic role for white grouper inside the untrawled areas. • Our study focus on the possible benefits obtained from the use of large offshore marine protected areas as a tool for ecosystem conservation. Abstract Fishing leads to drastic changes in ecosystems with a net loss of predatory biomass. This issue has been evidenced from historical ecological studies and from the evaluation of the effects of effective and large marine protected areas. In two fishery reserves off the northern Sicily coast the red mullet Mullus barbatus underwent an impressive biomass increment and a few piscivores fish species recovered after a trawl ban. The red mullet, more than 20% of all demersal fish in the untrawled areas, represented a huge food resource to its potential predators. By contrasting two trawled and two untrawled gulfs we figured out predator - prey relationships through the use of a combined approach based on trophic niche, stable isotopes data and biomass. We show that the white grouper Epinephelus aeneus and the black-bellied anglerfish Lophius budegassa are the most important predators of the red mullet with higher biomass in the untrawled areas. We also found a potential re-establishment of the trophic role for white grouper inside the untrawled areas. Our study highlights some of the benefits obtained from the use of large offshore marine protected areas as a tool for ecosystem restoration. [ABSTRACT FROM AUTHOR]

Within the framework of ecosystem-based management, restoration appears as a sensible option to counteract the global decline of coral reefs. Several techniques involving sexual and asexual coral propagules have been used for the restoration of reefs. Culturing of fragments has proved fruitful since it takes advantage of the capability of corals to asexually reproduce, providing a number of novel colonies that can be replanted. This method however, when using fragments detached from a colony, might be stressful for the wild donor. Astroides calycularis is an endemic and endangered Mediterranean scleractinian coral forming massive colonies mostly at shallow depth. It is subject to anthropogenic impact, particularly from damage due to accidental contacts by SCUBA divers, and it is expected to suffer from sea storms of increasing power under the projected climate change scenarios. Corals of opportunity (i.e. dislodged colonies found alive on the seabed) may be a useful resource for the restoration of A. calycularis reefs, given that the fragment-based transplant technique is effective for this species as it is for other massive corals. A one-year transplant experiment was carried out along an exposed rocky shore in NW Sicily (Mediterranean Sea) to test the feasibility of using fragments of corals of opportunity for restoration purposes. The transplants revealed high survival rates and higher number of new polyps than in control colonies. The original size of transplanted fragments did not influence their capability to bud new polyps and was not related to their survival rate. The applied technique provides the opportunity to restore rocky reefs, even the very shallow ones, through direct transplant of coral fragments, thus making reef restoration a feasible option in ecosystem-based management plans for this species. [ABSTRACT FROM AUTHOR]

Abstract: The behavioural deficit of hatchery reared (HR) fish used for stock enhancement is the main cause of their low survival in the wild. In this study the effects of predator and shelter conditioning on survival and dispersal of HR white seabream (Diplodus sargus) released at sea were investigated. The hypotheses were that conditioned white seabream would avoid predators more efficiently and would be more capable to shelter, showing higher survival and smaller dispersal than naïve fish. Six thousand HR white seabream (6.32±0.93cm total length) were allocated in twelve plastic tanks and divided in four experimental groups: three groups were conditioned with a predator, a refuge or both, while one group was left unconditioned and used as a control. The conditioning phase lasted 30days and was conducted using live conger eels as predators and pyramids of perforated bricks as refuges. Flight initiation distance (FID) and time to shelter (TS) were used as response variables to test the effects of conditioning in the arena, using a dummy conger eel. The effect of conditioning on post-release survival and dispersal was assessed through the monitoring of 1465 tagged seabream belonging to the four experimental groups, released at sea. Underwater visual census was used as monitoring technique. The sighting rate (SR) (sighted fish/released fish×100) and the distance (D) of each sighted fish from the release site were used as proxies for post-release survival and dispersion, respectively. In the arena, conditioned seabream showed significantly higher FID and lower TS than naïve fish. At sea, the estimated post-release survival of conditioned seabreams (SR=9.4%) was almost twice as much as that of naïve individuals (SR=5.5%). The dispersal of HR seabream acclimated to refuges from the release site (D =2.4±3.1km) resulted lower than in naïve fish (D =3.7±4km). This study indicates that predator and shelter conditioning of HR white seabream is an effective practise to increase their post-release survival at sea, and our findings provide support for effective stock enhancement initiatives. [Copyright &y& Elsevier]

• Accelerometers proved to be a promising tool to monitor the activity and behavior of lobsters. • The analysis pointed at the variance of roll body angle as the best proxy for lobster activity. • The presence of a predator caused a strong reduction of lobster activity. • In the presence of food lobsters reduced their activity in hours previous to sunrise. The knowledge of the activity pattern of marine organisms represents a crucial aspect in the studies on their ecology. In this paper, we used for the first time data from tri-axial accelerometers to provide an accurate description of the activity pattern of the European spiny lobster, Palinurus elephas. Sixteen lobsters (8 males, 8 females) were tagged with tri-axial accelerometers in order to monitor their activity in a mesocosm during four replicate trials. In each trial the lobsters were submitted to three treatments of the duration of one day each: exploration, presence of food and presence of a predator. The variance of roll body angle (VariRoll) was chosen among a number of available variables as a proxy of lobster activity during each treatment. The lobsters were more active during the night and in low-light hours than during the day. Moreover, they were i) more active without food or predator, ii) less active in the presence of a predator, iii) with an intermediate activity level (i.e. values of VariRoll) in the presence of food. Besides contributing to the knowledge of P. elephas ecology, the results of this study provide a new analytical method to describe activity patterns in slow-moving animals. [ABSTRACT FROM AUTHOR]