Spatio-temporal changes of Munida Rutllanti Zariquiey-Alvarez, 1952 (Decapoda: Galatheidae) in the North-Western Ionian Sea (Central Mediterranean)

The spatio-temporal pattern of Munida rutllanti distribution in the north-western Ionian Sea has been studied. Data were collected during 14 experimental trawl surveys conducted from 1997 to 2010 as part of the international MEDITS project. The hauls were carried out during day-light hours between depths of 10 and 800 m in the spring season. A progressive increase in the abundance index (N/km2) of M. rutllanti was observed from 2000 to 2008, then a sharp decrease was shown in the last two years. The greatest and lowest abundance indices were observed in the Apulian and central Calabrian sub-areas, respectively. The species was collected between 107 and 795 m in depth, with a significant increase and decrease over time in the maximum and minimum depth of finding, respectively. A highly significant increase over time in the mean carapace length was also observed in the whole study area. The widespread occurrence and increasing abundance of this species in the Ionian Sea could be related to the increase in temperature and the variation in hydrographic conditions which occurred in the Ionian basin during the EMT-BiOS phenomenon

Exploring Relationships between Demersal Resources and Environmental Factors in the Ionian Sea (Central Mediterranean)

The relationships between the abundance of demersal resources, environmental variables, and fishing pressure in the north-western Ionian Sea in the last two decades were evaluated. Data on the density collected during seventeen trawl surveys carried out from 1985 to 2005 were used. The following species were considered:Aristaeomorpha foliacea, Nephrops norvegicus,andParapenaeus longirostrisfor crustaceans;Merluccius merluccius, Phycis blennoides,andMullus barbatusfor teleost fish. The recruitment index was also considered forN. norvegicus, P. longirostris, M. merlucciusandMullus barbatus. Six candidate models were evaluated for each density and recruitment data set either combining fishing effort with global (NAO) and regional (SST and precipitation) climatic indices, or models separately involving fishing effort, NAO, or regional climatic indices as the only predictive variable. Model selection was carried out using an information-theoretical approach that applies Akaike's Information Criterion (AIC). High changes over time were observed for the density data and recruitment indices in each species. Apart from hake abundance and recruitment data, for which a clear positive relationship with the NAO index alone was detected, the changes observed in the other species seem to be the consequence of the interaction between bottom-up effects linked to changes in physical environment and top-down ones due to the fishing pressure

Revealing the coral habitat effect on benthopelagic fauna diversity in the Santa Maria di Leuca cold-water coral province using different devices and Bayesian hierarchical modelling

Data from two experimental longline surveys and two video inspections carried out in Santa Maria di Leuca cold-water coral province (Mediterranean Sea) during spring-autumn 2010 were used in order to compare the benthopelagic abundance and diversity between coral and non-coral habitats and between different devices. The sampling was carried out in two types of habitat: a coral habitat with carbonate mounds and a non-coral habitat characterized by intermound sea floor. A Bayesian hierarchical modelling approach to accommodate factors influencing community assemblages was used considering the number of species, the Shannon-Wiener diversity index and the two most abundant species represented by the European conger (Conger conger) and blackbelly rosefish (Helicolenus dactylopterus). A relevant effect of the habitat factor was observed for both the number of species and the diversity index, showing a higher species number and diversity index in the coral habitat than in the non-coral habitat. Concerning the relevance of fixed effects from the model on the probability of observing non-zero (positive) abundances, the devices considered, longline and baited lander, did not show different influence for either C. conger or H. dactylopterus. In the case of positive abundance, a relevant device effect was only observed for H. dactylopterus, showing higher abundances for longline than for baited lander. A habitat effect was detected, with positive abundances for both species in the coral habitat. This study proves that structurally complex habitats generated by cold-water corals influence the distribution and diversity of the benthopelagic fauna, and that the use of different devices can provide complementary useful results. Increased knowledge about the role of cold-water corals in the associated benthopelagic fauna could lead to better conservation of one of the most important hot spots of biodiversity in the Mediterranean Sea

Exploring spatio-temporal changes in the demersal and benthopelagic assemblages of the northwestern Ionian Sea (central Mediterranean Sea)

An exploration of the structure of demersal and benthopelagic assemblages in the north-western Ionian Sea was carried out by means of a set of statistical analyses. Self-organising map (SOM) and clustering methods applied to 183 taxa and their biomass (kg km-2) provided the classification of 1288 experimental hauls exploring the bathymetric range 10-800 m from 1995 to 2012. Six clusters were identified according to their similarities in species abundances (biomass), confirming the depth gradient as the main structuring agent. In order to identify key representative species in each cluster, the taxa were ranked by means of an indicator value index (IndVal) and the contribution of species to beta diversity (BD). Furthermore, the clusters were described by means of environmental and fishing characteristics. Particular habitat type, distance to canyon and fishing effort segregated the assemblages on the coastal shelf and slope. Temporal differences were detected in 2 bathyal groups, which were most likely affected by the 1990s environmental change in the deepwater circulation known as the Eastern Mediterranean Transient. The overall total BD in the study area was calculated as 0.79, with a temporal decrease observed at a rate of 0.7% yr-1. The approaches used are useful to identify and characterize the species aggregations inside complex faunal assemblages, without a priori assumptions about data distribution. These results can be a starting point for defining functional groups for Mediterranean food web modelling approaches, as well as for identifying indicator species to assess the environmental status in the context of the Marine Strategy Framework Directive

The influence of broilers’ body weight on the efficiency of electrical stunning and meat quality under field conditions

Water-bath stunning represents the most-applied stunning system in poultry slaughtering, but within the European Union, specific indications on electric parameters that should be used, such as voltage, are missing. The objective of this study was to evaluate the efficiency of two commercially available types of electrical equipment (A and B) on broilers with different live body weights and the influence of the tested parameters on meat quality. Experimental trials in a European Union-approved slaughterhouse were carried out using two different stunners. 6600 broilers, divided into three weight groups, were stunned applying different protocols based on the same current frequencies and intensity but different voltages. The state of unconsciousness (presence of corneal reflex and wings flapping) and post-mortem defects (pectoral hemorrhages and dark meat) were evaluated by blinded trained operators. The presence of corneal reflex and petechiae were the most reported consciousness signs and post-mortem injuries, respectively. Different weights played an important role within stunner A, registering statistical differences (p < 0.01) among groups. Considering injuries, an inverse relationship between body weight and lesions was found. The results highlighted the effectiveness of both stunning systems applying the best combination of electrical parameters considering the weight of the animal and ensuring its well-being

Dataset and species aggregation method applied to food-web models in the Northern Ionian Sea (Central Mediterranean Sea)

The ecological roles of the species in the food web are studied through the Ecopath with Ecosim modelling approach. In this modelling approach, the food web is described by means of functional groups, each representing a species, a life stage of a species, or a group of species with similar trophic, ecological and physiological features. Links between the groups are formally described by a set of linear equations, informed with ecological and fishing data. Here, the data input collected to implement 3 Ecopath models in the Northern Ionian Sea (Central Mediterranean Sea) from 1995 to 2015 are reported. This dataset applied to study the ecological roles of the demersal Chondrichthyes in the study area could be useful to explore different fishing management scenarios. A large dataset of over 300 taxa is shown detailing the ecological inputs, such as Biomass (kg km−2), Production and Consumption rates (y−1), Diet information (weight in %), and fishing data represented by Landings and Discards (t km−2 y−1). In particular, the fishery data described the catches of trawls, longlines, passive nets, other gears and purse seine. In addition, a description of the aggregation method of the species is shown

Macro- and megafauna recorded in the submarine Bari Canyon (southern Adriatic, Mediterranean Sea) using different tools

Macro- and megafauna were recorded in the submarine Bari Canyon, located in the southern Adriatic Sea (Mediterranean Sea) during an oceanographic cruise carried out in May-June 2012 and an experimental fishing survey conducted in November 2013. During the former, 20 benthic samples were taken using a Van Veen grab at depths between 268 and 770 m and four deployments of a baited lander, for approximately 43 hours of video records, were carried out at depths between 443 and 788 m. During the latter, eight longline fishing operations were conducted from 338 m down to 612 m. Eighty-five living benthic and bentho-pelagic species were recorded: 29 Porifera, 1 Cnidaria, 2 Mollusca, 11 Annelida, 1 Arthropoda, 19 Bryozoa, 3 Echinodermata, and 19 Chordata. Fifty-one species are new records for the Bari Canyon, and 29 species are new records for the Adriatic Sea. Among the Porifera Cerbaris curvispiculifer is a new addition for the Italian sponge fauna. The first confirmed record of living specimens of the bryozoan Crisia tenella longinodata is reported. A total of six Mediterranean endemic species have been identified, four Porifera and two Annelida. The bathymetric range of some species has been extended. New information acquired for deep sea species confirms their importance in the structure of cold-water coral communities. This study has updated knowledge on the biodiversity of the Adriatic Sea, as well as of the Bari Canyon in particular, one of the sites designated as “jewels of the Mediterranean” for which urgent conservation measures are needed

Macro- and megafauna recorded in the submarine Bari Canyon (southern Adriatic, Mediterranean Sea) using different tools

Macro- and megafauna were recorded in the submarine Bari Canyon (southern Adriatic Sea, Mediterranean Sea) during an oceanographic cruise carried out in May-June 2012 and an experimental fishing survey conducted in November 2013. During the former, a total of 20 benthic samples were taken using a Van Veen grab at depths between 268 and 770 m and 4 deployments of a baited lander, for about 43 hours of video records, were carried out at depths between 443 and 788 m. During the latter, 8 longline fishing operations were conducted from 338 down to 612 m. Eighty-five living benthic and benthopelagic species were recorded: 29 Porifera, 1 Cnidaria, 2 Mollusca, 11 Annelida, 1 Arthropoda, 19 Bryozoa, 3 Echinodermata and 19 Chordata. A total of 51 species are new records for the Bari Canyon, 29 new records for the Adriatic Sea. Among the Porifera Cerbaris curvispiculifer is a new addition for the Italian Sponge Fauna. The first certain record of living specimens for the bryozoan Crisia tenella longinodata is reported. A total of 6 Mediterranean endemic species have been identified: 4 Porifera and 2 Annelida. The bathymetric range of some species has been extended. New information acquired for deep sea species confirms their importance in the structure of cold-water coral communities. This study has updated the knowledge on the biodiversity of the Adriatic Sea, as well as of the Bari Canyon in particular, one of the sites designated as “jewels of the Mediterranean” for which urgent conservation measures are needed