A seasonal survey was undertaken, over a year, of phytoplankton from surface water in the western English Channel (Station L4) measuring mycosporine-like amino acids (MAAs), photosynthetic pigments and microscopic counts. Ground level solar radiation (ultraviolet-B, ultraviolet-A and photosynthetically active radiation; UV-B, UV-A and PAR) was measured at a nearby site. From this we estimated in situ solar irradiance received by phytoplankton using measurements of the mixed layer depth and calculations of the 50% light level cut-off. The MAAs occurred year round, with concentrations increasing rapidly during spring and summer (maximum 8·5 μg l−1) to levels exceeding those of chlorophyll-a (chl-a maximum 3·6 μg l−1). On two occasions, increases in specific MAAs coincide with algal blooms. In spring, increases in mycosporine-glycine (λmax 310 nm in the UV-B) coincide with a bloom of the prymnesiophyte Phaeocystis pouchetii and in July and August increases in an unidentified MAA (λmax 328 nm) match a bloom of the diatom, Guinardia striata (=Rhizosolenia stolterfothii). Concentration of MAAs, but not chlorophyll, correlate with in situ irradiance. The ratio of MAA to chl-a increases linearily with in situ irradiance received by phytoplankton reaching 13·9 nmol MAA (nmol chl-a)−1 at 101 W m−2. Evidence of photoinduction is observed during the P. pouchetii bloom with a four fold increase in the concentration of mycosporine-glycine (maximum 2 pg cell−1) as UV-B:PAR ratio increases from 0·0011 to 0·0014. Dinoflagellates, although contributing to <10% of biomass, are found through the correlation of MAAs to the biomarker peridinin, to contribute to baseline levels of MAAs throughout the year. Our MAA:chl-a values for the English Channel are similar to those measured in coastal areas of southern USA. Similarities with studies on Antarctic phytoplankton are also found with the dominance of porphra-334 and the presence of mycosporine-glycine in P. pouchetti.

Survey work was carried out in the Greater Minch area on the west coast of Scotland in 1997. The survey covered an area of 17,000 km2, extending from Kinlochbervie in the north-east to the Stanton Banks in the south-west. Acoustic and ground-truth surveys were conducted using the seabed discrimination system RoxAnn© and underwater television cameras. This paper examines the macro infaunal component of the benthic community from 28 stations sampled throughout the region. From these, 198 taxa were identified, while species per station ranged from 11 to 69 with a maximum abundance of 2100 individuals per m2. Biomass ranged from 2·3 g m−2 to 103·1 g m−2, with a mean value of 21·0 g m−2. Multivariate statistical analysis of the infaunal data revealed the presence of three benthic assemblages, which were closely related to habitat type. An investigation into the dominant feeding guilds or isotrophic groups from each assemblage revealed that surface deposit feeding dominated the very fine sand habitats while both surface and subsurface deposit feeding were very common in the silt communities. A combination of feeding types (namely carnivorous, suspension and surface-deposit feeding) was associated with the sand habitats. The findings of this study are discussed in relation to those in similar habitat types.

Inspection videos of four offshore platforms in the central and northern North Sea were used to study the development of fouling communities on clamps and guides of oil export risers over an 11-y period (1989–2000). Results from multivariate analyses (multi-dimensional scaling and analysis of similarities) indicated that distinct assemblages developed in different geographical locations. These differences were mainly due to the protracted development of the Metridium senile (Cnidaria: Actinaria) zone on the northern sector platforms. The vertical zonation of fouling organisms was similar on all installations, although the water depth at platform locations varied from 80 to 169 m, indicating that fouling organisms display a wide bathymetric tolerance. This study has highlighted the value of long-term data present in operational inspection videos for the study of fouling communities.

A 3-D hydrodynamic model of the circulation, salinity and temperature within the embayment of Plymouth Sound, UK and its surrounding English Channel waters has been implemented. Thorough validation of the model shows that the main hydrographic features of the region, as characterized by these variables, are reproduced. The general flow characteristics, and the resultant distribution of freshwater from the main riverine source (the River Tamar), are described. The potential fate of contaminant releases within Plymouth Sound is investigated. Whitsand Bay, located south-west of Plymouth Sound, is shown to be a likely recipient for a proportion of these contaminants, irrespective of where in the Sound the release occurs, and as such is considered to be vulnerable to pollution events originating there.

A detailed cartography of surficial sediments from Golfo San Jorge, Argentina is presented. Cluster analysis and principal components analysis (PCA) were applied considering the weight percentage of every granulometric fraction, carbonate concentration and the depth of 39 stations carried out during research cruises on board the RV ‘Captain Oca Balda’ (INIDEP).  The results defined three sectors: Sector 1, an area near the coast including Dos Bahías and Tres Puntas capes; Sector 2, a deep area far from the coast; and Sector 3, a coastal area and a south-east area between Tres Puntas cape and the inner area of the gulf. The first sector is characterized by the predominance of a coarse granulometric fraction and carbonate content. The second is defined by depth and presence of a fine granulometric fraction; while the third sector is considered a transitional sector, between the first and the second, dominated by fine sands. Sectors belong to environments of different kinds of energy or hydrodynamic conditions.

The detailed anatomy of the noses of Kogia breviceps and K. sima (Kogiidae: Cetacea) is described in greater detail than previously. Probable functions of component parts of the nose are deduced from their geometry and physical properties of the tissues. It is concluded that control of the air making the sound is similar to that found in scottish bagpipes with a single reed, that sounds are produced by air being forced from the vocal valve and is resonated in an unusual chamber having cords and membranes, similar to human vocal cords. It is then reflected by air filled ‘mirrors’ and conducted and intensified through a megaphone-like ‘horn’ which is surrounded by air and contains tissues rich in spermaceti oil. Sound then passes through the melon where, by changes in temperature of the spermaceti oil, it is actively focused and possibly scanned. Thermal properties of Kogia spermaceti oil are described and related to previously made sound velocity and density measurements. The way sound production and reflection can continue while large variations of pressure are experienced during deep dives, is suggested. A structure for controlling the temperature of the melon is described. It is considered unlikely that the spermaceti oil is used for buoyancy control in Kogia. Some comparisons are drawn with Physeter catodon, Xiphius and Tursiops and some implications for research on other cetaceans are outlined.

Organotin (OT) compounds were determined in surface sediments and mussels Mytilus edulis from two major estuaries of the UK, the Mersey and the Thames, approximately one decade after legislation banning the use of tributyltin (TBT) compounds on small boats. Tributyltin concentrations in Mersey sediments ranged from 0·007–0·173 μg (as Sn) g−1 dry wt, increasing from the most upstream site, Fiddlers Ferry, towards the middle section of the estuary, and were highest at Stanlow, perhaps indicative of sources from the Manchester Ship Canal (MSC). A further peak in TBT concentrations occurred at New Brighton, opposite Liverpool Docks. Tributyltin was the predominant butyltin (BT) species in sediments (approximately 50%). Despite the fact that BTs represented only 4% of the total (HNO3-extractable) tin in sediments there was a linear relationship between these two tin compartments. Furthermore, BTs in mussels were correlative with total extractable tin in sediment, though in contrast to sediments, 85% of the total tin in mussels was made up of BTs, the most predominant of which was TBT. Concentrations of TBT in mussels increased from 0·058 μg Sn g−1 dry wt at the mouth of the estuary to 0·214 μg Sn g−1 dry wt at their upstream limit, close to the entrance to the MSC (Eastham). Triphenyltin (TPT) compounds were detected in only one sediment sample (New Brighton, 0·359 μg Sn g−1 dry wt) and one mussel population (Egremont, 0·022 μg Sn g−1 dry wt). Tributyltin concentrations in sediments from the Thames Estuary were marginally lower (0·002–0·078 μg Sn g−1 dry wt) than those found in the Mersey: highest concentrations were present in the upper estuary and decreased seaward. Again BTs contributed only a small percentage (<1% mean) towards the total tin loading in Thames sediments, but represented most of the tin burden (80%) in mussels. In contrast to sediments, TBT levels in mussels from the Thames Estuary were slightly higher than the Mersey (concentrations ranged from 0·100 μg Sn g−1 dry wt at the mouth to 0·302 μg Sn g−1 dry wt upstream) suggesting that TBT bioavailability is disproportionately higher in the Thames. Phenyltins were not detected in Thames samples.

Submarine cliffs are typically crowded with sessile organisms, most of which are ultimately exported downwards. Here we report a 24 month study of benthic fauna dropping from such cliffs at sites of differing cliff angle and flow rates at Lough Hyne Marine Nature Reserve, Co. Cork, Ireland. The magnitude of ‘fall out’ material collected in capture nets was highly seasonal and composed of sessile and mobile elements. Sponges, ascidians, cnidarians, polychaetes, bryozoans and barnacles dominated the sessile forms. The remainder (mobile fauna) were scavengers and predators such as asteroid echinoderms, gastropod molluscs and malacostracan crustaceans. These were probably migrants targeting fallen sessile organisms. ‘Fall out’ material (including mobile forms) increased between May and August in both years. This increase in ‘fall out’ material was correlated with wrasse abundance at the cliffs (with a one month lag period). The activities of the wrasse on the cliffs (feeding, nest building and territory defence) were considered responsible for the majority of ‘fall out’ material, with natural mortality and the activity of other large mobile organisms (e.g. crustaceans) also being implicated. Current flow rate and cliff profile were important in amount of ‘fall out’ material collected. In low current situations export of fallen material was vertical, while both horizontal and vertical export was associated with moderate to high current environments. Higher ‘fall out’ was associated with overhanging than vertical cliff surfaces. The ‘fall out’ of marine organisms in low current situations is likely to provide an important source of nutrition in close proximity to the cliff, in an otherwise impoverished soft sediment habitat. However, in high current areas material will be exported some distance from the source, with final settlement again occurring in soft sediment habitats (as current speed decreases).

Oncholaimus cobbi was described from the Brazilian coast. The area studied, Coroa Grande, is located in Sepetiba Bay, State of Rio de Janeiro, Brazil. Sampling was carried out monthly, from May 1998 through April 1999. Most of the population was represented by adults, of which non-ovigerous females were the most abundant category. The species reached its highest population density during the warmest months, and the highest densities of males and ovigerous females were seen in February 1999.

The presence of suctorian ciliates attached to the cuticle of heavily ornamented free-living marine nematodes, especially the family Desmodoridae, has been reported. Observations of nematode hosts and their attached ciliates were made from samples extracted from very fine muddy sands of tropical Australian sea grass meadows. Measurements of the point of attachment of the ciliates revealed that they tend to position themselves near the anus/cloaca of the nematode host.

Recent measurements of benthic currents, within the depth range where the highest abundance of the hexactinellid sponge Pheronema carpenteri are found, have been made and compared to historical data for the northern Porcupine Sea Bight region where no Pheronema have been recorded. Bottom currents at a location where Pheronema have not been recorded are much higher than a location where the sponges have previously been sampled. The measurements provide some evidence to support the hypothesis that the sponges favour a location adjacent to regions where enhanced bottom tidal currents are found, but currents experienced by the sponges themselves are much reduced.

Mediterranean fish of the Trachinidae and Uranoscopidae families are characterized by a poison apparatus on the 1st dorsal fin. These fish hide by burying themselves in the sand using cryptic mimicry. Nevertheless, if they are discovered before they have completely buried themselves, or perceive a potential source of danger when already covered, they will raise their 1st dorsal fin which has a bright black spot on the inter-radial membrane. We have shown that this black vexillum acts as a threatening visual cue and that the movements accompanying black mark display can be defined as aggressive mimicry.  We therefore thought it interesting to investigate the black mark display in some species of Soleidae, a behaviour never before reported in the literature. In these fish, the black marks are situated on the right pectoral fin which, as a result of the distortion and re-arrangement of some anatomical parts during development, shifts to a dorsal position in adults. Soles also bury themselves in the sand, and they too display their marked fins on the approach of a possible predator, just like fish belonging to the above dangerous families.

Water column sampling for nutrients, chlorophyll-a and bacteria was carried out at different time-scales covering 12 hours and one month; ten replicated samples were taken for estimating the stochastic variability. Two sampling stations were established on the north coast of Crete (eastern Mediterranean), one in Heraklion harbour and a second one at an exposed coastal area. All variables measured were significantly higher in the port. Only chlorophyll-a showed an increasing coefficient of variation with increasing time scale at both sampling sites, whereas the other variables showed different patterns between the two sites.

Fauna associated with the common kelp along the Norwegian coast, Laminaria hyperborea, was sampled at four sites covering 1000 km of coastline. Exploitation of the kelp habitat by the fauna, and the ways in which habitat size and seasonal variations affect the kelp fauna community were analysed. The study focused on mobile macrofauna, of which 238 species were found on 56 kelps sampled, with an average density of almost 8000 individuals per kelp. Amphipods and gastropods were the most diverse and abundant fauna groups. The species composition was different on the lamina, stipe (with epiphytic algae) and holdfast. A similar pattern of epiphyte- and holdfast-fauna composition was found for all regions. Lowest diversity and abundance were found on the lamina, and highest diversity in the holdfast. Highest abundance was found on the stipe in summer, but there were large variations between sites and seasons, from a few individuals to more than 80 000 animals per stipe. Neither seasonal changes nor variation in habitat volume affected the number of species significantly, but abundance was significantly related to season and habitat volume. These variations were most pronounced for stipe fauna. Laminaria hyperborea offers a heterogeneous habitat exploited by a diverse and abundant invertebrate community, its abundance depending on local and regional variations in kelp size.

Four species of sea horses (Syngnathidae: Hippocampus) were found in Peninsular Malaysia during a survey conducted between April and August 2001. These were Hippocampus trimaculatus, H. spinosissimus, H. kuda and H. kelloggi. All four species were found in the Straits of Malacca; two species (H. trimaculatus and H. spinosissimus) in the east coast of Peninsular Malaysia in the South China Sea; and three species: H. trimaculatus, H. spinosissimus and H. kuda in the south coast, Straits of Johor. There were habitat and depth separations by species. Hippocampus trimaculatus, which was found throughout the coastal waters of the Peninsular, were reported to inhabit chiefly among gorgonians at approximately 20–40 m depth. The habitat and depth in H. spinosissimus were rather similar to that of H. trimaculatus; but the former species was less widespread in the west coast. Hippocampus kuda was confined to shallow water between 1 to 3 m, and was found in seaweeds and sea grass meadows in a few estuaries; whereas H. kelloggi inhabited gorgonians and sea whips in deep-water below 65 m. Mean standard lengths are given. No sexual size dimorphism was detected in any of the species.

Third-stage larval and adult infrapopulations of the whaleworm Anisakis simplex sensu lato (s.l.) (Nematoda: Anisakidae) from their respective fish, cephalopod and cetacean hosts caught or stranded in the Galician coast (north-west Spain), were analysed for heavy metals by atomic absorption spectrometry. Results suggest that the whaleworm may accumulate lead and copper to levels far in excess of their host tissues.

Intertidal meiofauna were collected from various locations around the Pina Basin, Recife, Brazil. The basin is a shallow restricted environment which receives large quantities of untreated sewage, and is therefore polluted, eutrophic and hypoxic. The meiofauna were identified to major taxa (nematodes, copepods, polychaetes, oligochaetes, turbellarians, gastrotrichs, rotifers, ostracods, acari, and juvenile amphipods and bivalves) and counted. Subsamples of nematodes were extracted and identified to the level of genus. The nematode community structure was typical of organically-enriched intertidal areas world-wide. Various environmental measurements were made, including sediment structure, salinity, dissolved oxygen and biochemical oxygen demand in the overlying water. Of these the latter two were shown to be most closely linked to variation in meiobenthic community structure. A much closer link was shown between variation in nematode assemblage structure, biochemical oxygen demand in the overlying water and gravel content of the sediment.

Specimens of the marine isopod Excirolana chiltoni collected in Hokkaido (northern Japan) showed epibiont protozoan ciliates belonging to two species of loricate suctorian: Acineta hokkaidensis sp. nov. and Acineta excirolensis sp. nov. Acineta hokkaidensis is larger, with an elongated body covered by a lorica. The short stalk had 15–18 longitudinal striations. The contractile vacuole was located apically. The macronucleus was posterior. Two fascicles of capitate tentacles located at the edges of the apical area project through the anterior aperture of the lorica. The suctorians were found on the pereiopods and antennae of the isopod. Acineta excirolensis which is smaller and triangular in shape, showed a very wide lorica and a noticeably long stalk. At the edges of the apical region there were two lobulate actinophores, each with a fascicle of capitate tentacles. The contractile vacuole was anterior and spherical, and the macronucleus was central. These suctorians were attached as planobionts on the pereiopods of the isopod. The taxonomic position of both species was analysed in relation to other similar species previously described.

A comparative morphological study was performed on the otolith growth patterns of 11 species of the genus Merluccius. The otolith growth pattern, based on the radius of the first eight growth increments (GI) from the otolith core, was determined from transverse sections of sagitta otoliths. The structure and periodicity of the GI were identified based on previous knowledge. Two cluster analyses were performed using GI width as a proxy for otolith growth. The first cluster analysis corresponded to the juvenile (immature) period of the fish including the mean width of the first four GI. The second analysis compared the mean width of the next four GI, i.e. those corresponding to mature fish. The results showed an important environmental influence in immature fish; while after maturation, the GI pattern was also related to an endogenous influence depending on the phylogenetic line.

The proportion of life history phases in red seaweeds is an important descriptor of population structure. This paper describes the relative abundance of gametophytes and tetrasporophytes of Mazzaella oregona (Rhodophyta: Gigartinales; formerly M. heterocarpa), focusing particularly on the effects of wave exposure on the proportion of both life history phases. In two different rocky points in Barkley Sound (Pacific Canada), gametophytes were, in proportion to tetrasporophytes, relatively more abundant under low wave exposure than under high wave exposure in July 2002, during the period of highest abundance for this species. The inverse relationship between the G:T ratio and the degree of wave exposure also occurs for local M. splendens, but not for local M. parksii. Differences in frond size and population density between these three sympatric species are related to the effects of wave exposure on their G:T ratio.