Specimens of the chemoautotrophic symbiont-bearing hydrothermal vent clam Calyptogena pacifica were collected from hydrothermal vents at the Endeavour segment of the Juan de Fuca Ridge. Total lipid was extracted from gill, foot and mantle tissues, and lipid class and fatty acid composition determined by thin layer chromatography with flame ionization detection (TLC–FID), gas chromatography (GC) and gas chromatography with mass spectrometry (GC–MS). An abundance of n–7 monounsaturated fatty acids (MUFA), especially in the gill, reflected the large contribution of chemoautotrophic symbiotic bacteria to the nutrition of this clam. The absence of n–8 MUFA suggests that C. pacifica does not contain methanotrophic symbiotic bacteria. Low levels of highly unsaturated fatty acids (HUFA) such as 20:5 n–3 and 22:6 n–3 were detected in C. pacifica and their presence is attributed to a source other than chemoautotrophic symbiotic bacteria. Significant levels of non-methylene interrupted dienoic fatty acids and eicosatrienoic acid (20:3) were also detected in C. pacifica and it is suggested that these fatty acids are synthesized from n–7 MUFA as alternatives to HUFA. In contrast to shallow water bivalves, elevated levels of triglyceride were detected in the gills compared to the mantle.

The harbour porpoise (Phocoena phocoena) is one of the common small cetaceans of European waters. This discreet and undemonstrative species is strongly represented throughout the cold waters of the northern hemisphere, and is the most abundant cetacean in the North Sea. In the last few years, some observations and studies indicate a shift of harbour porpoise distribution in European waters, from northern regions of the North Sea to the southern North Sea, English Channel and Celtic Sea. This shift may include a comeback around the coasts of France. Harbour porpoises inhabit shelf-waters and are often observed in shallow waters, conditions offered for instance by the coasts of Brittany in north-western France. We used opportunistic sightings, aerial survey and a ten-year strandings database to study the presence of harbour porpoises along the coasts of Brittany. Opportunistic sightings made by non-specialists did not confirm a strong presence of harbour porpoises along the Brittany coasts, most probably because of the undemonstrative behaviour of this cetacean. However, aerial survey and stranding analysis indicate that harbour porpoises have become natural inhabitants of the Brittany coasts once more: 68.6% of cetacean school sightings made during a 1578 km aerial survey of the Brittany coasts concerned harbour porpoises, with an encounter rate of 1.5 individuals per 100 km that peaked to 5.8 per 100 km to the top of the shallow waters of the south-western Western English Channel. The number of harbour porpoise strandings increased each year from 1997 to 2007, making a total of 135 along the coasts of Brittany. Other cetaceans did not show such an increase during the same period. Strandings of harbour porpoises were also characterized by an apparent increase as a proportion in relation to all the cetacean strandings during the months of September to January, by a marked impact of by-catch during winter, and by an almost total absence of stranded calves. The comeback of the harbour porpoise along Brittany coasts is clearly confirmed by our data, and a stable population seems to be established again along the coasts of Brittany. This tends to confirm the shift of the distribution of the species in certain European waters. Long term monitoring, diet and genetic studies are now planned for a better understanding of this shift, and for the effective implementation of a conservation plan.

The trophic behaviour, stomach contents, and morphology of the feeding appendages, with emphasis on setae, of a species of Laomediidae, Axianassa australis (Crustacea: Decapoda: Thalassinidea), were investigated. This species is a deposit feeder. The 32 described setal types were clustered in four main categories: plumed, serrate, plumodenticulate and simple. By examining the setae and spatial position of the segments of the appendages, it is possible to infer that the main function of the 1st and 2nd pereiopods, the 3rd pair of maxillipeds, as well as the dactylus, propodus, carpus and merus of the 2nd maxilliped, is to brush particles. The ischium, basis and coxa of the 2nd maxilliped appear to be specialized for particle retention. For the remaining mouthparts, brushing is generally the main function of the basal endites, while the coxal endites retain particles. Patterns of morphological adaptations to feeding habits are proposed for the Thalassinidea based on a review of the literature. Setal diversity, ratio of plumodenticulate to serrate setal types and mandible morphology are linked to ecological adaptations to trophic modes. Conversely, the presence and degree of development of the crista dentata appear to be related to phylogenetic heritage rather than to feeding mechanisms. Stomach contents are also indicative of trophic modes used by the species; while the predominance of small particles can indicate either filter or deposit feeding, stomach contents with high quantities of large particles suggest deposit feeding as the exclusive trophic mechanism.

Minke whale (Balaenoptera acutorostrata) distribution was derived from a 12 year observation programme in the Mingan Islands (Canada) and related to three geological features of the sea-floor: maximum depth, topography and geomorphology. Minke whale distribution was not uniform nor random in relation to maximum depth and topography, however, no evident trend was found. The most prominent factor was the presence of underwater sand dunes, where significantly more minke whales were observed than on any other bottom types. Because sand dunes are the favoured habitat of the minke whale major prey in the study area, an indirect link between minke whale distribution, geomorphology and substrate type is suggested.

Many factors threaten the survival of marine turtles, such as incidental capture by fisheries, habitat degradation, pollution and diseases. One of the most important diseases is fibropapillomatosis (FP), characterized by the development of benign skin tumours. FP predominantly affects juvenile green sea turtles (Chelonia mydas) and involves a complex multifactorial aetiology. For several years, it has been noted that the prevalence of FP tends to be higher in marine environments under the influence of human activities, leading to the hypothesis that environmental pollutants play a role in the epidemiology of this disease. Organochlorine compounds (OCs) are persistent organic pollutants with immunosuppressive and carcinogenic effects in humans and wildlife. OC levels (α-BHC, β-BHC, α-endosulphan, β-endosulphan, endosulphan sulphate, pp′-DDD, op′-DDD, pp′-DDE, op′-DDE, heptachlor, dicofol and mirex) were quantified through gas chromatography with a micro-electron capture detector (GC-μECD) in liver and fat samples from 64 juvenile green sea turtles. Specimens with and without FP were analysed, after being caught at three feeding areas off the Brazilian coast: Ubatuba, Praia Grande and Vitória. OC levels were comparable to those observed in similar studies, and no consistent difference was observed between sea turtles with and without FP. This study helps to elucidate the contamination profile in sea turtles caught at feeding areas off Brazil and confirms that green sea turtles are exposed to OCs, which may play a negative role in the health of this species.

The diversity and structure of meiobenthic nematodes and macrobenthic infauna were studied at four widely spaced subtidal sites around the UK coast in relation to a number of measured environmental variables. The stations were situated on soft sediments at water depths of 53 to 95 m and are intended as long-term monitoring locations as part of the UK National Marine Monitoring Programme. Similar benthic assemblages were encountered in comparable environmental conditions. The distribution of nematode and macrofauna species was mainly governed by the geographical location of the habitat and the granulometric composition of the substrate. There was no evidence of any adverse effect on the measures of benthic assemblage structure arising from trace metal concentrations in the sediment, indicating the relatively unpolluted nature of the offshore locations under investigation. Nematode and macrofauna assemblages exhibited stable patterns over time periods of three years.

Austinixa aidae inhabits burrows of the ghost shrimp Callichirus major at Perequê-açu beach, Ubatuba, Brazil. We described the host-use pattern and sexual dimorphism of A. aidae to test for monogamy given the generality of this mating system in the subfamily Pinnothereliinae (family Pinnotheridae) to which A. aidae belongs. Against expectations, A. aidae lives as solitary individuals within burrows more frequently than expected by chance alone. Additional observations suggested that A. aidae exhibits a polygynandrous mating system with males moving among burrows in search of receptive females. First, only 21% of the burrows harboured heterosexual pairs of crabs and the body size of paired crabs was poorly correlated. This suggests pair instability and frequent shifts among burrows by male and/or female crabs, as reported before for other symbiotic crustaceans in which the body size of paired crabs is poorly correlated. Second, males paired with females that were sexually receptive (without embryos) or that have been receptive recently (carrying early embryos) were found more frequently than expected by chance alone. The above agrees with that reported for species in which sexual pairing does not last long. Third, sexual dimorphism in terms of claw size and coloration was evident. Claws were larger in males than in females, a condition that argues in favour of male–male competition in A. aidae. In addition, the body coloration of males was more similar to the sand grains of the beach than that of females. This sex-specific coloration suggests that males are ‘better adapted' than females to roam on the surface of the beach in search of burrows because their coloration should diminish the risk of detection by predators. Experiments are needed to reveal the details of the polygynandrous mating system herein inferred for A. aidae and to understand those conditions favouring particular reproductive strategies in symbiotic decapod crustaceans.

Ptychodactiaria, currently recognized as an order equivalent to Actiniaria (sea anemones sensu stricto) and Scleractinia (‘true’ or hard corals) of cnidarian class Anthozoa, contains three monotypic genera, Dactylanthus, Ptychodactis, and Preactis, in two families, Ptychodactiidae and Preactiidae. Features that had been considered distinctive to the order among hexacorallian anthozoans were that gametes mature in protrusions from the mesenteries, as in octocorallian anthozoans, and that gametes do not mature embedded in mesogloea. However, we found that ptychodactiarian gametes develop in the mesenteries, surrounded by mesogloea, as in other sea anemones. We conclude that the three species constitute a clade, the most distinctive feature of which is medially fused mesenteries at the proximal end of the body. This clade merits subordinal status within order Actiniaria. We redefine Ptychodactiaria and its component taxa, moving Dactylanthus from family Ptychodactiidae to family Preactiidae.

Bioeroding sponges of the Cliona viridis species complex play a large role in carbonate cycling and reef health. In the present study we provide the first record and a description of a Mediterranean lineage of C. viridis (Schmidt, 1862) in the south-western Atlantic. Specimens were collected in Maricás Archipelago, Rio de Janeiro State in September 2010 by scuba diving at 10–12 m depth and deposited in the Porifera collection of Museu Nacional, Universidade Federal do Rio de Janeiro. Morphologically, the specimens presently examined are very similar to those described in the beta and gamma growth form from the Mediterranean. The Brazilian and Mediterranean specimens share large and irregular papillae over 2 cm in diameter, megasclere tylostyles up to 500 µm long and microsclere spirasters with up to five twists and 34 µm long. A Maximum Likelihood analysis of 28S rDNA of C. viridis, C. aprica, C. jullieni, C. schmidti and C. varians was performed for a genetic identification of the Brazilian specimens. The Brazilian material is phylogenetically closer to the Mediterranean C. viridis than to the Caribbean and Indian Ocean members of this species complex included in the present analysis. Our results suggest that C. viridis is a cryptogenic species with a distribution extending from the Mediterranean to the eastern Atlantic and in the SE Brazilian coast or further.

This one-year study investigated spatial and temporal variations in the abundance and biomass of the pink shrimp species, Farfantepenaeus paulensis and Farfantepenaeus brasiliensis, in the Conceição Lagoon, southern Brazil (September 2003–August 2004). The influence of salinity, water temperature, and rainfall on shrimp distribution was evaluated. Shrimps were caught monthly at three areas within the Conceição Lagoon (Canto, CA; Centro, CE; and Costa, CO). A total of 744 shrimps were sampled, with F. brasiliensis being the dominant species. The two penaeid species were present throughout the year and significant differences were observed between seasons, with F. paulensis being more abundant during the summer and F. brasiliensis in the autumn, suggesting differential migration timing to the sea, differences in recruitment time and an ontogenetic temporal partitioning. Farfantepenaeus paulensis exhibited a homogeneous spatial distribution, whereas F. brasiliensis was more abundant in CE and CO, suggesting that habitats in this coastal lagoon are heterogeneous. Among the abiotic factors, temperature and salinity seemed to be important variables in defining seasonal and spatial patterns, respectively, of the abundance of F. brasiliensis.

The force required to dislodge mussels from the substrate is known as attachment strength. This feature has been mostly studied in mytilids inhabiting the intertidal of consolidated rocky substrates, whereas it has been less studied in sedimentary substrates. The aim of this study was to evaluate the attachment strength and the number of byssal threads of Brachidontes rodriguezii in two sites with mobile substrates in San Antonio Bay, Argentina [Punta Verde (PV) and Punta Delgado (PD)]. PV has relatively higher current velocities and coarser grain size than PD. Along coastal line transects at two different levels of the mid-intertidal of each site, the attachment strength was measured. The number of byssal threads in collected mytilids and the weight of the sediment adhered to them were recorded in the lab. The attachment strength, the number of byssal threads and the sediment adhered to the byssus differed significantly between levels and sites. Mytilids from the mid-level of both sites where the density was relatively lower, had a significantly greater number of byssal threads and higher weight of sediment adhered. This study reveals that a high amount of coarse sediment adhered to the byssus affects the attachment strength of B. rodriguezii in ecosystems relative to unstable substrates. We underline the importance of mobile substrates in understanding attachment features (attachment strength and byssal threads) of mytilids in this unstable ecosystem.

The morphology of burrows constructed by the eel goby Taenioides cirratus was studied using resin castings of burrows in situ as well as aquarium observations. Burrows had several openings, one of which was associated with a crateriform mound. The structure of the burrows consisted of the mound, gently sloping interconnected tunnels, and many short cul-de-sac side branches. The presence of the mound suggests that the fish actively process sediment.

Since 1912 extensive investigations have been carried on in the Laboratory of the Marine Biological Association at Plymouth on the genetics of Gammarus Chevreuxi Sexton, a brackish-water amphipod (Allen and Sexton '17 and '20, see also Sexton '13 and Sexton and Matthews '13).

During the course of the work, numerous individuals have appeared showing abnormalities in sexual behaviour or structure. In view of the interest attaching to such forms, especially after the work of Goldschmidt ('20), Banta ('16), Sturtevant ('20) and others, it was deemed advisable to collate and publish the available data in spite of their some what fragmentary character.

In normal circumstances, the males of Gammarus chevreuxi mate with the females some days (3 to 9 days) before fertilisation is due to take place. Unless the female is mated for the first time she will normally be carrying in her brood-pouch a brood of developing embryos. After hatching, the young are carried about 24 hours before extrusion, and during that time they come to the anterior end of the brood-pouch and feed on what the mother is eating. Finally they are extruded by a voluntary opening of the brood-pouch. Immediately afterwards the female moults, whereupon fertilisation occurs and a new batch of eggs is extruded into the pouch.

The pair have by now separated, and remain separated usually until the embryos have gone through about half their development in the pouch.

Cannibalism is of fairly frequent occurrence, the male eating the female immediately after she has moulted. It is extremely rare for the normal female to eat a male.

The predatory effects of Pachygrapsus marmoratus on populations of the intertidal limpet Patella depressa were analysed on rocky shores located on the central coast of Portugal. Nocturnal observations on crab feeding behaviour were conducted and experimental exclusion cages were set in the substratum to assess density effects on limpets. The results indicated that although crabs feed on adult limpets the predatory level was minimal. Crabs used consistent tactics to detach limpets from the substratum but the majority of the attacks were unsuccessful, possibly due to morphological and behavioural adaptations of limpets. An alternative recruitment hypothesis is advanced to explain non-significant differences between experimental treatments and a possible predatory role on shaping levels of recruitment on lower levels of the shore is considered.

Feeding and vertical distribution of pelagic chaetognaths were studied at coastal and open-sea stations in the northern part of the South Adriatic Pit during five cruises from April 1993 to February 1995. Chaetognaths were more numerous in the upper 100 m, decreased conspicuously with depth, and were captured only rarely between 600 and 1000 m. Copepods were the main food for the most abundant species in all layers. Cannibalism was evident in all species. Feeding on fertilized chaetognath eggs by Pseudosagitta lyra and Mesosagitta decipiens is reported for the first time. The food containing ratio (FCR) and number of prey items per chaetognath (NPC) of Flaccisagitta enflata were highest during the reproductive period. Higher FCRs and NPCs for M. decipiens and P. lyra were noted below 100 m, where the contribution of older specimens increased with depth and the abundance of copepods decreased.

This work is a continuation of my preliminary paper on the same subject, which was published in a former number of the Journal of the Association (vol. vi., p. 373, January, 1902).

This paper presents results of a study conducted on the trawling industrial fishery fleet of Merluccius gayi in south-central Chile, and the resulting interactions with the South American sea lion (Otaria flavescens). This study is based on observations made during September 2004, when incidental sea lion catch in the trawls was 6.3 sea lions/working day (1.2 sea lions/trawl−1). A total of 82 animals were incidentally caught, of which 12 were found dead, and the 70 remaining suffered from internal bleeding and/or fractures as a result of their capture. 83.3% of the fatalities occurred during nocturnal trawls, which comprise 30% of all observed trawls. Possible mechanisms of sea lion take are discussed. This note presents the first records of sea lions incidental by-catch by the trawler fleet along the south-east Pacific coast of Chile.

Populations of Caryophyllia smithii were studied at three sites of differing sedimentation regime in Lough Hyne, Ireland. The height, length, width and density of individuals were measured along with the depth of accumulated sediment on the rock substratum at each site. Calyx size was largest at the site of least sedimentation and smallest at the site of most sedimentation. In contrast, height of individuals was greatest at the site of most sedimentation and smallest at the site of least sedimentation. The height of individuals was correlated with the level of surrounding sediment (Pearson's correlation 0.836 P<0.05). The uppermost limit of C. smithii corresponded with the downward limit of the infralittoral zone at each site; 15, 13, and 12 m at the low, mid and highly sedimented site respectively. Density averaged over depth was greatest (70 ind m−2) at the site of moderate sedimentation and lowest (13 ind m−2) at the site of least sedimentation. Density was also found to increase with depth at the sites of moderate and high sedimentation.

The effect of sponge encrustation on swimming ability of Chlamys hastata was determined by investigating swimming behaviour, scallop morphometry, and energy expended during swimming with and without commensal epibionts. Scallops swam significantly longer after sponge encrustation was removed from their shells, but no significant differences were detected in swimming elevation or distance. Scallops with sponge encrustation showed no adductor muscle hypertrophy or changes in shell morphometry compared to scallops without encrustation. However, C. hastata did exhibit scaling relationships associated with maximizing swimming efficiency. Specifically, shell width and adductor muscle mass were positively allometric with shell height, while shell mass was negatively allometric with shell height. Scallops increased their energy expenditure (both aerobic and anaerobic) during valve-clapping, but no significant difference was detected between unencrusted (43·0 μmol adenosine triphosphate [ATP] consumed during a two min escape swim) and sponge-encrusted (40·0 μmol ATP) scallops. Scallops in both treatments derived 86% of the energy used for swimming from anaerobic sources. The lack of substantial differences between scallops with and without commensal sponges is partially explained by the observation that even heavy sponge encrustation increases the immersed weight of the scallop by only 5%. The presence of a sponge encrustation does not appear to inhibit swimming by this scallop species.

The feeding of the most important chaetognath species (Sagitta enflata, Sagitta minima, Sagitta setosa and Sagitta serratodentata) found in a grid of 35 stations in the north Aegean Sea (Strymonikos and Ierissos Gulfs) was investigated through gut content analysis during five sampling periods from June 1997 to May 1998. Sagitta enflata and S. minima were the most abundant species in summer–autumn 1997 and in spring 1998, respectively. Copepods were the main food for all chaetognath species in spring 1998, while cladocerans in summer–autumn 1997 dominated the diet, especially of S. enflata. In September 1997, the juvenile specimens of cladocerans were the most important prey of the immature Stage I specimens of S. enflata, which resulted from the major breeding period in late summer. The estimated impact of chaetognath predation on the copepod and cladoceran communities ranged between 0.02–2.76% and 0.01–1.29% of the copepod and cladoceran standing stock, respectively. Stage I specimens of S. enflata accounted for nearly 90% of the total copepod and cladoceran standing stock consumed per day by the total population of this species in September 1997.