We examined the feeding ecology (diet, trophic width and trophic position) of five demersal shark species (Mustelus mustelus Linnaeus, 1758, Galeus melastomus Rafinesque, 1810, Scyliorhinus canicula Linnaeus, 1758, Scyliorhinus stellaris Linnaeus, 1758, Squalus blainville, Risso, 1826) coexisting in the north-eastern Aegean Sea (around Gökçeda Island) by combining stomach content and stable isotope analyses. The results indicate clear differences in diet between the five sharks. Cephalopods were mainly found in diet of S. stellaris and M. mustelus and the stomachs of G. melastomus, S. canicula and S. blainville included fish. S. blainville showed the highest trophic position in respect of stable isotope analysis (TPsia = 4.89) around Gökçeada Island. It was followed by G. melastomus (TPsia = 4.57). Direct isotopic values (both stable nitrogen and carbon) and isotopic niche width based on the Standard Ellipse Area (SEA) clearly differed among the five shark species. In particular, S. blainville was isotopically segregated from the other shark species studied, showing a narrow isotopic trophic niche and higher trophic level. In contrast, M. mustelus had the widest trophic niche of the five species studied. The niche width of S. stellaris was narrower than M. mustelus and S. canicula but wider than S. blainville and G. melastomus. SEA showed that G. melastomus has a specialized feeding strategy in the area. There is no overlap between S. canicula and S. stellaris in trophic width.

The embryos of Icelandic capelin (which spawn subtidally) tolerate as low temperatures, and are as euryhaline, as those of Balsfjord capelin which spawn intertidally. The median lethal lower temperature for Icelandic capelin eggs exposed for 6 h to low temperatures in frozen seawater films (34‰) is -6.3°C. The median lethal high salinity (6 h exposure) is 88.3‰. Eggs were reared and hatched successfully in all salinities from 1.5 to 34‰. When exposed to high salinities capelin eggs shrink in a matter of seconds (shrinkage being manifested in depressions of the chorion), but resume a normal shape in a few minutes as salts diffuse into the perivitelline fluid. Evidence is presented to show that mortality in frozen seawater films is due to osmotic dehydration, rather than to a final invasion by ice crystals. A model of freezing avoidance in capelin eggs is described.

The five sea turtle species occurring in Brazilian waters are susceptible to threats, including incidental catches by fisheries. Studies on incidental captures in fishing gears are the main focus of several conservation actions due to high sea turtle fishery mortality worldwide. This study provides the first evaluation of incidental sea turtle catches by industrial bottom trawl fisheries operating in Brazilian waters. Four twin-trawler vessels were monitored between July 2010 and December 2011 by captains who voluntarily completed logbooks. Forty-four turtles were captured during the 1996 tows (8313 fishing hours), resulting in a catch of 5.3 ± 0.8 turtles per 1000 h per unit effort. Captured species included the loggerhead turtle (Caretta caretta, 22 individuals), olive ridley turtles (Lepidochelys olivacea, 21 individuals) and one green turtle (Chelonia mydas). Water depth was the only variable that significantly affected sea turtle captures according to Generalized Linear Models. The capture rates reported in this study ranked sixth in relation to other published studies of similar fisheries occurring worldwide. Considering the importance of this region for sea turtles, the increasing evidence of sea turtle mortality and the goals of the National Action Plan for Conservation of Sea Turtles in Brazil, it is essential to identify the main threats towards these animals and propose mitigating solutions to reduce sea turtle mortality induced by fishing activities. This study provides results that may guide future research and goals in meeting sea turtle conservation strategies.

Following primary settlement and metamorphosis in Myiilus edulu (L.), the original larval stem glands (S1 and S2) increase enormously in size in the plantigrade. These glands, packed with mature secretion, discharge into a multi-partitioned posterior ducted system which is transitional in form between that of the larva and the adult. The gross enlargement of the stem glands appears to be an adaptation for frequent and copious production of byssus material during the bysso-pelagic and attachment phases of early post-larval life. This interpretation is supported by the fact that the volume ratio of the stem glands to the foot declines during subsequent growth of the young mussel and that other glands take over the function of byssus stem formation in mature mussels. Enhanced dispersal of post-larvae by bysso-pelagic drifting would account for the widespread and heavy fouling of offshore platforms by the almost exclusively intertidal mussel, particularly where these structures are far distant from coastal stocks.

The publication in 1953 of the English language translation of Vinogradov＇s massive compilation of data upon the chemical composition of numerous animals was a valuable landmark in this field of study. Since then, papers too numerous to summarize, have appeared in the literature employing ever more accurate analytical techniques. So far as marine animals in particular are concerned, the theme which has been consolidated by such subsequent work revolves around their ability to extract and concentrate a variety of chemical elements from their environment. Frequently, however, no obvious function can be ascribed to the more obscure of these often highly concentrated elements.

A description is given of a new type of apparatus designed to sample plankton from the immediate vicinity of the sea bottom, and purely from this region. Details of the construction are given and the relative merits of the design are briefly discussed.

It could be used for quantitative hauls.

A small additional net serves to sample the smaller benthic fauna at the same time as bottom plankton is being sampled.

1. S. horsti occurs on the Hampshire coast of the Solent near the mouth of the Lymington River, in glutinous grey mud associated with Corophium volutator.

2. The species is distinguished by the following characters: coloration; dorsal and ventral grooves present on the proboscis throughout its length; collar forming a slight operculum posteriorly; ventral muscle bands of the trunk forming projecting ridges; rounded genital ridges present, the gonads beginning within 1 mm. of the collar; 100–140 pairs of gill slits; longitudinal muscle fibres of the proboscis arranged in nine or more concentric rings; ventral septum of the proboscis short; stomochord straight, with ventral diverticulum and wide lumen throughout; no dorsal glomerulus present; single proboscis pore on the left side; proboscis skeleton embracing half to two-thirds of the circumference of the buccal cavity and extending one-fourth to one-third of the length of the collar; four epidermal zones present in the collar; collar cavities completely separated; anterior extensions of the collar cavities extending into the neck of the proboscis; perihaemal cavities separate posteriorly but confluent in front of the level of the tips of the crura, and extending into the neck of the proboscis as far as the proboscis pore; neural keel well developed and in continuity with the epidermal nerve layer at intervals; no dorsal diverticulum of the buccal cavity; branchial epidermis characterized by the predominant intensely eosinophil glandular elements; tongues broader and projecting further into the lumen of the pharynx than the septa; epibranchial ridge formed by two convex ridges bounding a median groove; oesophagus divided into three regions; 4–8 intestinal pores; hepatic region of gut not sacculated and with an expanded lumen; gonads not lobed; oocytes attain a size of 0·23 × 0·17 mm.; yolk cells present in the ovaries.

3. The probable identity of the specimen of Saccoglossus from the French coast of the English Channel, recorded by Caullery & Mesnil (1916) as S. kowalevskyi, with this species is discussed.

Fifteen individuals of four marine fish species (Torpedo marmorata, Raja clavata, Scorpaena porcus and Scorpaena scrofa) caught in the Dardanelles, Turkey, were examined for the leech Pontobdella muricata and Trachelobdella lubrica; 18 P. muricata and 23 T. lubrica were found on gills, at the base of the fins, and abdomen on 14 of the 15 fish.

The densities of two common intertidal/shallow subtidal bivalves, Soletellina alba and Arthritica helmsi, were sampled in vegetated and unvegetated habitats of the Hopkins River estuary on three occasions during the autumn/winter 1995. Winter flooding coincided with mass mortalities of the infaunal bivalve S. alba, but not A. helmsi. Mortalities were apparent for individuals living deeper in the sediment (≈35 cm) in vegetated and unvegetated habitats, but small S. alba (<1 mm) were less susceptible to mortality than larger individuals (>1 mm). Mortalities were similar across different habitat types and sediment depths, and at multiple sites within close proximity to the estuary mouth.

Wet biomass of principal plankton components and whole plankton standing stock were assessed in waters of the Heron Island ring reef and surrounding deep lagoon. Biomass of phytoplankton ranged between 30 to 120 mg m−3, without its pronounced depletion over the reef shallows. Picocyanobacteria and prochlorophyte algae contributed over 70% of this biomass. Biomass of bacterioplankton varied between 75 to 340 mg m−3, with its maximum over the reef flat. Biomass of planktonic protozoa's ciliates and zooflagellates ranged between 20 to 110 mg m−3. The daytime biomass of zooplankton varied between 490 to 1590 mg m−3 in the deep lagoon in the zone of intense tidal currents. Over the reef shallows, it was 10–20 mg m−3. At night, it rose there up to 800 to 4000 mg m−3 as the result of emerging demersal zooplankton from the benthic substrates. The time scale of nocturnal emerging by different taxa was also documented. Biomass of whole demersal zooplankton communities hiding by the daytime in bottom substrates at the reef flat was found to be over 100 g m−2. Problems of nutrition planktivore reef fauna related to the plankton production and abundance are discussed.

Intra- and interspecific variation in a 658 bp long part of the cytochrome c oxidase subunit 1 (COI) gene of the mitochondrial genome, i.e. a suggested ‘DNA barcode’, was assessed in four north-west European species of the marine tubificid genus Tubificoides: T. benedii, T. amplivasatus, T. heterochaetus and T. kozloffi. Within species mean genetic distance was from 0.10% (T. amplivasatus) to 0.14% (T. benedii), between species from 19.3% to 22.9%. For T. benedii and T. amplivasatus, material collected in two separate areas, The Sound between Denmark and Sweden, and the Koster area about 330 km to the north along the Swedish west coast, showed a geographically random distribution of COI haplotypes, suggesting that each of these two species forms a continuous population in southern Scandinavia. We conclude that the COI gene is suitable as a barcode marker for the secure identification of these species, at least within the area investigated. Tubificoides heterochaetus is reported for the first time from Denmark.

This study focuses on spatial and temporal distribution and species composition of phytoplankton in the south-western Caspian Sea between July 2009 and March 2010. Samples were collected from 11 stations along three transects: Lisar, Anzali and Sefidrood. Among 44 identified phytoplankton species, diatoms (70.2%) and cyanophytes (25.0%) were dominant. The average phytoplankton abundance was calculated as 1.085E + 05 cells l−1. Among the phytoplankton groups, diatom density was higher (70.2%) than two out of three of total abundance in density of 1.085E + 05 cells l−1. Cyanophytes were the second important group (25.0%) contributing to total phytoplankton. Dinoflagellates, chlorophytes and euglenoids were other contributors to total phytoplankton. Diatoms Dactyliosolen fragilissimus and Skeletonema costatum and cyanophyte Oscillatoria sp. numerically dominated in the system. There were major changes in phytoplankton composition and average phytoplankton density was higher than those documented in 1996–1997 and 2005. The average concentrations of dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP) and dissolved inorganic silicate were 14.5 ± 6.32, 1.14 ± 0.44 and 5.10 ± 3.98 μM, respectively, and these concentrations were strikingly high. Increases in DIN and DIP concentrations were more than twofold compared to recorded values during the last 2 decades due to the eutrophication. Fluctuations in nutrients played an important role in the variation of phytoplankton composition and abundance. Chlorophyll-a concentrations varied between 3.22 and 16.1 μg l−1 and there was a significant increase in chlorophyll-a (8.13 ± 5.72 μg l−1) compared to the values in 1996–1997 (1.44 ± 1.48 μg l−1), 2001 (2.62 ± 1.48 μg l−1) and 2005 (2.14 ±1.94 μg l−1).

We identified and quantified the benthic macrofauna associated with decomposing leaves of Rhizophora mangle and Laguncularia racemosa, to observe the differences in the abundance and composition of macrofauna between these mangrove species, and to examine whether the abundance and composition of organisms changed with different stations and collection times. Benthic macrofauna, mainly polychaetes and amphipods, were recorded from the fifth day after the installation of the experiment. Annelids including Oligochaeta and Polychaeta were the most numerous group. Crustacea were represented by peracarids (Amphipoda and Tanaidacea) and decapods. Of Hexapoda, only juvenile forms and pupae were present. The most abundant polychaete species was Perinereis brevicirrata, followed by Capitella cf. capitata, Heteromastus filiformis and Neanthes succinea. In one-way analysis of variance (ANOVA) there were no statistical differences between the macrofauna of mangrove species, seasons, or collection times, except among collection times for R. mangle litter bags. Two-way ANOVA showed homogeneity for macrofauna abundance between the groups of collection times for both mangrove species. The richness was similar for R. mangle litter bags, and showed a significant difference for L. racemosa. Abundance and richness were also similar between the mangrove species. The colonization of detritus by benthic invertebrates followed a successional sequence during the decomposition process. This suggests that the density of these organisms and their foraging behaviour affected the decomposition rates of leaves of R. mangle and L. racemosa.

A replica method involving the use of a polyvinylsiloxane impression material with a resin cast, particularly suitable in the study of marine biofilms, is described. The technique has advantages over other methods in that it is quick, non-toxic, non-destructive and inexpensive. Replicas of critical-point dried eggcases of the dogfish Scyliorhinus canicula (L.) (Elasmobranchii: Squaliformes) showed the replica to be true down to the size of bacteria. It was also possible to replicate larger areas such as patches of living barnacles on an intertidal rock.

The study of marine biofilms often involves the use of destructive techniques such as conventional scanning electron microscopy (SEM), histology and in vacuo spectroscopic methods (Baier & Meyer, 1986), so a single surface may not be examined repeatedly. Alternatively, the surface of interest may not be amenable to examination by standard techniques due to, for example, large size or incompatibility of the material of interest. In materials science the use of replica techniques to overcome such problems have been common (Goodhew, 1973), though techniques commonly involve the use of solvents (Loh, 1989) or silicone elastomers that may have a curing period of several hours (Gordon, 1984) and are consequently unsuitable for the study of biofilms. Scott (1982) reviewed the use of dental impression materials for field use in metallurgy and in recent years, dental impression materials have been used in the study of plant morphology (Green & Linstead, 1990). In this paper we consider the use of a hydrophilic polyvinylsiloxane impression material in the study of both microscopic and macroscopic marine biofilms.

There are numerous examples of symbiotic associations between Foraminifera and unicellular algae. Most of these Foraminifera are larger Foraminifera which occur in the shallow, oligotrophic waters of tropical seas (Table 1). Some of the symbiotic algae have been studied by light microscopy (Table 1, nos. 1–6). Dietz-Elbrächter (1971) suggested that the symbionts of Heterostegina depressa might be diatoms. She was, however, unable to prove this statement satisfactorily. Hottinger & Dreher (1974) published electron micrographs of the symbionts of H. depressa and Operculina ammonoides. From these micrographs identification of the symbionts was not possible. To date, only the symbionts of the following Foraminifera have been classified by electron microscopy:Archaias angulatus, Sorites marginalis, Globigerinoides ruber, Hastigerina pelagica and Globigerinoides sacculifer (Table 1, nos. 7,10,12,13,14).

The present study was carried out to evaluate the biological characteristics of Pachygrapsus marmoratus in the southern Black Sea, Ordu, Turkey. A total of 1503 crabs, ranging from 0.9 to 4.3 cm in carapace length (CL), were collected monthly from November 2012 to October 2013. Female:male ratio was found to be 1:1. Measured male and female crabs were grouped in 0.49 cm CL class intervals. The mean CL, carapace width (CW) and weight (W) were determined as 2.55 ± 0.02 cm, 2.90 ± 0.02 cm and 14.21 ± 0.27 g, respectively, for all individuals. Correlation analysis was also conducted to reveal relationships between size parameters for males and females as well as between egg number and size. The b values of CW and W for male, female and ovigerous crabs were found to be 3.1, 3.06 and 2.95, respectively. Number of large-sized individuals and growth rate was higher in males compared to females.The highest correlation was found between CW and CL in both sexes. The mean condition index values were calculated as 49.03 for males and 45.79 for females. Ovigerous females were observed only from May to July 2013. The fecundity estimates ranged from 8989 to 151,578 eggs/crab, with an average value of 57,814.53 ± 3349 eggs/crab. The egg diameter ranged between 328.40 μm and 423.38 μm, with a mean size of 365.83 ± 1.97 μm. There was a positive relationship between egg number and female size.

The genus Kolga has been revised. Kolga nana (Théel, 1879) is re-established and a new species, Kolga kamchatica sp. nov., is described. The new species was found in the Kurile–Kamchatka Trench at 6225–6236 m water depth. The three species of Kolga, K. hyalina, K. nana and K. kamchatica, differ mainly in morphology of tube feet ossicles. For the first time, swimming activity is reported in K. nana.

This study examined the relationships between food ration, intra- and interindividual variation in food consumption, observed behaviours and the growth of individual juvenile greenback flounder (Rhombosolea tapirina: Teleostei) held singly and in groups. Agonistic, feeding and neutral behavioural units were identified and described using video records and focal sampling. Agonistic behaviour, including nipping and pushing, were infrequent and accounted for <5% of behavioural units. The influence of food ration upon agonistic behaviour was investigated using three groups of six flounder offered either a low, medium or high food ration. The total number of agonistic behaviours recorded in each group did not differ significantly (P>0.05) suggesting food ration had little influence upon the total number of agonistic behaviours performed. Single flounder showed less intra- and less interindividual variation in day-to-day food consumption than in groups of six. Variation in food consumption increased with increasing food ration in single and in groups of flounder. Significant positive correlations between food consumption, intraindividual variation in food consumption and specific growth rate provided indirect evidence for the presence of feeding hierarchies. The small contribution made by agonistic behaviour to the total number of behaviours recorded for each group suggests exploitation competition, as opposed to interference competition, was the dominant competitive mechanism employed by juvenile greenback flounder.

Several type series of unusual and poorly known genera of Syllidae have been examined. New diagnoses for the following genera and re-descriptions of their type species are provided: Anguillosyllis, Clavisyllis, Lamellisyllis and Nuchalosyllis; Brachysyllis, previously synonymized with Dioplosyllis, is herein considered to be a valid taxon. The species Brachysyllis infuscata is also re-described. Three genera are considered to be non-valid taxa: Braniella, synonymous with Anguillosyllis; Alluaudella, synonymous with Odontosyllis; and Exogonella, synonymous with Parexogone. Their type species herein are re-described and assigned to their corresponding valid genus. Finally, Exogonoides is considered nomina dubia since its relationships with other syllids could not be established. Keys to species of Anguillosyllis and Brachysyllis are also included.

The development of the female gonad in Loripes lucinalis (Lamarck) from Brest Harbour (Brittany, France) was examined over a one-year period. Throughout the year, several size classes of eggs were observed, and spawning was seen to occur twice. A major spawning occurred in May leaving the gonad completely empty in June. A minor spawning is also thought to have occurred between the November and December sampling periods. These spawnings do not seem to correlate with the classical environmental factors often associated with gametogenesis and spawning, namely temperature and chlorophyll a levels. The energy for gametogenesis seems to be obtained from the transfer of metabolites to the oocytes via specialized follicle cells. These metabolites are believed to be of heterosynthetic origin. An inverse relationship exists between the thickness of the follicle cell epithelium and the occupancy level of the gametes. During periods of gonadal proliferation, these cells represent the nutritive cells of the gonad, but during periods of non-proliferation they make up a somatic tissue used for metabolite storage until conditions are adequate for gonadal development.