The Norway lobster, Nephrops norvegicus is a target fishery species in European waters. The stock assessment of N. norvegicus is complicated because it is caught in commercial gear only when it emerges from its burrow. Landings are lower in winter, and feeding limitations have been hypothesized as the cause. Wild large-sized male lobsters were sampled each season (winter, spring, summer and autumn), and two groups of animals were kept in captivity for 90 d (fed and food-deprived). The hepatopancreas and muscle were dissected, weighted, frozen for biochemical analyses (proximal analyses and DNA/RNA) and fixed in Bouin solution for microscopic observations. The oxygen consumption rates in the wild individuals caught in the spring and in the captive animals after the treatments were measured. Significant differences among the experimental groups were observed in the lipid concentration of the hepatopancreas and muscle, the water content in the hepatopancreas, and the numbers of vacuoles and pyknotic nuclei in the cells of the tubules of the hepatopancreas. The results showed that the wild Norway lobsters generally presented intermediate values between those observed in the food-deprived and the fed lobsters kept in captivity, but the values were closer to those obtained for the fed animals. This finding indicates that the wild animals exhibit a good nutritional condition throughout the year. Therefore, the wild males of N. norvegicus do not face food deprivation during winter as is suggested by the pattern of commercial catches, the flow of organic matter, and the moulting period/reproductive behaviour of the species.

Balanophyllia europaea is an endemic Mediterranean sublittoral zooxanthellate solitary coral. Given the broad distribution of the species throughout many areas of the Mediterranean surprisingly little is known of preferred habitat niches or susceptibility of the species to environmental change. In this study we investigated in the laboratory the net prey capture rates of the coral achievable under a range of flow velocities (2.5, 5, 7.5 and 15 cm s−1) and under exposure to different suspended particulate concentrations (0, 7.3 and 170 mg l−1). In recirculation flumes we simulated both commonly occurring and the occasionally high flow velocities and various suspended particulate concentrations reported from the Gulf of Lions (north-west Mediterranean). We then delivered ca 500 A. salina nauplii l−1 as food (Artemia salina nauplii) to the flumes and monitored net prey capture over time. We found net prey capture rates by the species to be highest under flow velocities of 5 cm s−1, with 230 µg C coral individual−1 h−1 achieved. The presence or absence of even environmentally high particulate concentrations (up to 170 mg l−1 resuspended seabed material) did not significantly affect the net prey capture rates achieved by the coral polyps. We found that net prey capture in Balanophyllia europaea is not inhibited during periods of heavy particle exposure, as has been observed in other temperate scleractinian corals. Also, flow velocities of ca ~5 s−1 appear to be optimal for maximum net prey capture by the species.

Benthic habitat and epibenthic megafauna are described from seabed photographs taken in or near three potential deep-water Marine Protected Areas on the Hebridean Slope, surveyed in 1988, 1995–96 and 1998. Broad bathymetric zones are defined by visible substratum characteristics, and by cluster analysis using presence/absence of identified fauna. The shelf edge and upper slope (to 350 m depth) showed current-swept coarse substrata with a very sparse fauna. A transition to finer sandy sediments was apparent at 350–470 m, with a greater abundance of mobile epifauna. The brittlestar Ophiocten gracilis occurred at high density below 600 m depth in all three areas. Southern stations indicated an abrupt lower boundary for this zone at ca 1000 m. In the north, rippled sands with xenophyophores occurred below the O. gracilis zone at 1000–1100 m. Xenophyophores were also seen in smaller numbers at this depth in the south. From ~1300–1600 m a seabed of burrowed fine mud was recorded in both northern and southern areas. Bioturbated sediments on the Rockall Trough floor at ~2060 m supported more visible epifauna, principally the brittlestar Ophiomusium lymani and the octocoral Acanella arbuscula. The bathymetric pattern differs from a scheme proposed in 2010 for the deep north-east Atlantic in the lack of any obvious zonal boundary at 750 m. No cold-water corals or sponge aggregations were observed. Trawl marks were observed in all three areas, particularly in the 1998 northern survey, with highest frequency at 1300–1400 m.

Pinna nobilis is an endemic Mediterranean species of high economic and cultural importance. Nowadays, it is under strict protection as a dramatic decline in its populations has been recognized, assigned to the combined effect of fisheries and habitat degradation. This study attempts to evaluate, by non-destructive sampling, the current status of P. nobilis populations in the south Aegean Sea (Dodecanese island complex), where they have been affected for centuries by practically uncontrolled harvesting. Population density and total length of individuals was estimated by diving along strip transects at six islands. Two stations were randomly selected per island, and two depth zones were surveyed per station. Additionally, temporal sampling was carried out at Astypalaia Island from March 2004 to June 2006, to assess relevant trends in density of individuals and size structure of the population. In total 1372 P. nobilis individuals were measured in situ to estimate maximum shell length. The studied populations showed increased density in the shallower depth zone and sheltered sites; small-scale environmental regimes are proposed as shaping factors of P. nobilis distribution. Increased density was also detected during the cold period of the year, probably related to recruitment success. In the lower depth zone the P. nobilis population consisted of larger individuals. A significant decrease in size was detected temporally as mean length was smaller in December 2004; in the same month the presence of small-sized juveniles was depicted in a left-shift in size–frequency distribution. These observations are probably related to the reproductive biology of the species.

We examined the benthic macroinfauna at three strata during two seasons (winter and summer) on two sandy beaches (dissipative and reflective) in south-eastern Brazil. The hypothesis raised is that effects of morphodynamics and zonation determine the structure of macroinfauna, with dissipative beaches having comparatively higher species richness and density than the reflective beaches. Flamengo beach (dissipative) had higher species richness but lower density compared to Grumari beach (reflective). A high dissimilarity in assemblage structure (91.75%) was detected between the two beaches. Zonation in the occurrence of macroinfauna was detected for the two beaches in the two examined seasons. At Grumari beach, Emerita brasiliensis occurred mainly in stratum 1 (intertidal swept zone) while Saccocirus sp. occurred in stratum 2 (infralittoral at 0.5 m depth), whereas at Flamengo beach E. brasiliensis and Enoploides sp. had the highest density in stratum 1 (intertidal swept zone) whereas Scolelepis goodbodyi and Donax uncinata dominated in stratum 3 (infralittoral at 1.0 m depth). Scolelepis goodbodyi, Dispio uncinata, Enoploides sp., Nematoda and Trileptium sp. were associated with higher a Dean parameter and content of organic matter at Flamengo beach. In contrast, Hastula sp., Donax sp., Pisionidens indica, Hemipodus californiensis, Saccocirus sp. and Phyllodocidae were associated with the higher wave period and grain size of Grumari beach. The hypothesis that macroinfauna structure differs between the beaches and strata was confirmed, with the dissipative beaches having comparatively higher richness but lower density than the reflective beaches.

Two new species of South African Syllidae of the genus Syllis Lamarck, 1818 are described. Syllis unzima sp. nov. is characterized by having unidentate compound chaetae with long spines on margin, a characteristic colour pattern and its reproduction by vivipary. Vivipary is not common among the polychaetes, but most representatives occur in the family Syllidae Grube, 1850 (in five other Syllis species, two species of Dentatisyllis Perkins, 1981 and two species of Parexogone Mesnil & Caullery, 1818). Syllis unzima sp. nov. differs from the other viviparous species in having large broods (>44 juveniles) which develop synchronously. Development of the juveniles is similar to that of free-spawning Syllis species, but the appearance of the first pair of eyespots and the differentiation of the pharynx and proventricle occur later in S. unzima. Syllis amicarmillaris sp. nov., is characterized by having an elongated body with relatively short, fusiform dorsal cirri and the presence of one or two pseudosimple chaeta on midbody parapodia by loss of blade and enlargement of shaft. Syllis unzima sp. nov. was found in high densities on cultured Holothuria scabra Jaeger, 1833 with single specimens found on a cultured Crassostrea gigas Thunberg, 1793 and on coralline algae, respectively, while S. amicarmillaris was found mainly in sediment outside an abalone farm and less frequently on cultured Haliotis midae Linnaeus, 1758. We discuss the possible benefits of the association with H. scabra to S. unzima sp. nov.

Through application of carbon (C) and nitrogen (N) stable isotope analyses, we investigated the benthic trophic structure of the upper-slope off southern Chile (~45°S) including a recent methane seep area discovered as part of this study. The observed fauna comprised 53 invertebrates and seven fish taxa, including remains of chemosymbiotic fauna (e.g. chemosymbiotic bivalves and siboglinid polychaetes), which are typical of methane seep environments. While in close-proximity to a seep, the heterotrophic fauna had a nutrition derived predominantly from photosynthetic sources (δ13C > –21‰). The absence of chemosynthesis-based nutrition in the consumers was likely a result of using an Agassiz trawl to sample the benthos, a method that is likely to collect a mix of fauna including individuals from adjacent non-seep bathyal environments. While four trophic levels were estimated for invertebrates, the fish assemblage was positioned within the third trophic level of the food web. Differences in corrected standard ellipse area (SEAC), which is a proxy of the isotopic niche width, yielded differences for the demersal fish Notophycis marginata (SEAC = 5.1‰) and Coelorinchus fasciatus (SEAC = 1.1‰), suggesting distinct trophic behaviours. No ontogenic changes were detected in C. fasciatus regarding food sources and trophic position. The present study contributes the first basic trophic data for the bathyal area off southern Chile, including the identification of a new methane seep area, among the furthest south ever discovered. Such information provides the basis for the proper sustainable management of the benthic environments present along the vast Chilean continental margin.

Renibacterium sp. QD1, a bacteria strain capable of hydrolysing chitosan, was isolated from the homogenate of small crabs. An extracellular chitosanase, Csn-A, was purified from the QD1 fermentation broth. The enzyme was purified to homogeneity, with a yield of eight-fold, 67% recovery and a specific activity of 1575 U/mg proteins. The molecular weight of Csn-A was estimated to be 26.1 kDa by SDS-PAGE. Unlike other chitosanases, the purified Csn-A displayed maximal activity at a pH range of 5.3–6.5, and it was stable in a broad pH range of 5.0–10.0. The optimum temperature for chitosanlytic activity was 55°C. The enzyme activity was strongly stimulated by Mn2+ but inhibited by Fe3+, Cu2+, Al3+, Zn2+ and SDS. TLC analysis demonstrated that Csn-A hydrolysed N-deacetylated polymeric glucosamines into chito-biose and -triose in an endo-type manner. The amino acid seuquence of Csn-A showed close identity with an uncharacterized chitosanase of strain ATCC33209.