Little is known about the cleaning behaviour of shrimps in comparison to that of cleaner fish, and only recently have cleaner shrimps been shown to remove parasites effectively from coral reef fish. Here we describe patterns of cleaning interactions between Pederson shrimp Ancylomenes pedersoni and fish clients in St Thomas, US Virgin Islands. Clients observed here were members of at least 16 fish families, including three previously unreported client families. Most cleans lasted <20 seconds; surgeonfish were cleaned most frequently, but lizardfish and groupers received the longest cleans. The shrimp formed social groups of varying sizes on individuals of the host sea anemone Bartholomea annulata, which served as the centres of their cleaning stations. The number and duration of cleans per station increased with the number of resident shrimp, however most anemones hosted small groups of fewer than four individuals, while larger groups of up to nine individuals were relatively rare. Some client fish chased away other fish and competitively excluded them from anemone stations. We conclude that these shrimp clean a wide diversity of clients, vary their clean duration with fish identity, and clean more when in large groups. In addition, clients in part control these patterns of interaction by interfering with access to these stations by other clients.

1. Fortnightly samples were taken with a fine-meshed net in single vertical hauls at different positions in the Clyde Sea-Area.

2. Each stage of Calanus present, from ovum to adult, was counted, and charts were constructed expressing these results for one year as total numbers and as percentage composition.

3. Calanus passes the autumn and early winter mainly in its Stage V copepodite form.

4. In general, total numbers were high in September, 1931, and fell steadily to a minimum in March; in Loch Fyne the minimum occurred i n April.

5. A sudden increase was observed in May and numbers rose to maximal values; the decline also was sudden.

6. Reproduction began in February and three plainly marked breeding periods were observed between February and July.

7. The time taken by the egg in developing into the adult was four weeks.

8. The total life of a Calanus during the summer was estimated to be about two and a half months; in winter it is five to six months.

9. In Loch Fyne a noticeable lag occurred during the winter and early spring.

10. The number of Calanus present in the autumn of 1932 was considerably less than.at the same time in 1931. This may have been due to a shortage of food.

Here we provide baseline data on the distribution and abundance of Mola mola within the Irish and Celtic Seas, made during aerial surveys from June to October during 2003–2005. These data were considered in conjunction with concurrent observations of three potential jellyfish prey species found throughout the region: Rhizostoma octopus, Chrysaora hysoscella and Cyanea capillata. A total area of 7850 km2 was surveyed over the three years with an observed abundance of 68 sunfish giving a density of 0.98 ind/100 km2. Although modest, these findings highlight that the species is more common than once thought around Britain and Ireland and an order of magnitude greater than the other apex jellyfish predator found in the region, the leatherback turtle (Dermochelys coriacea). Furthermore, the distribution of sunfish sightings was inconsistent with the extensive aggregations of Rhizostoma octopus found throughout the study area. The modelled distributions of predator–prey co-occurrence (using data for all three jellyfish species) was less than the observed co-occurrence with the implication that neither jellyfish nor sunfish were randomly distributed but co-occurred more in the same areas than expected by chance. Finally, observed sunfish were typically small (∼1 m or less) and seen to either bask or actively swim at the surface.

Long-term fluctuations in the abundance of the copepod Calanus finmarchicus in the north-east Atlantic are compared to the North Atlantic Oscillation index over the period 1958–1995. The strong climate-plankton link previously observed is confirmed and a simple linear regression model is constructed with the aim of predicting the abundance of the species several months in advance. For the years 1993–1995 the model predictions are in accordance with observations, but not in 1996 when the abundance of C. finmarchicus fell, although the climatic scenario indicated that a sharp increase should have occurred. The potential causes of this discrepancy are discussed.

All groups of meso- and macro-zooplankton in the North Sea off Northumberland, at a depth of 53 m, were studied during a 15-year period (1969–83); copepod productivity was estimated from biomass and growth rates. Phytoplankton were seasonally bi-modal with peaks in April and August–October; copepods were uni-modal peaking in June–July. The predatory zooplankters: larval fish, decapods, ctenophores, medusae (the summer-autumn predators) peaked between May and September, while chaetognaths and euphausiids (the winter predators) peaked in December–January. Copepods and the summer-autumn predators were seasonally and inter-annually positively correlated, and declined in abundance from 1974 to 1980. Euphausiids and chaetognaths on the contrary increased in abundance during these years, and were seasonally and inter-annually negatively correlated to the copepods. The mean annual abundance of copepods was positively related to the previous winter's minimum, and inversely related to the abundance of chaetognaths and euphausiids. Annual copepod productivity averaged 1260 kJ m-2 year-1, and showed no relationship to other groups of plankton.

The mean annual towing speed of the Continuous Plankton Recorder (CPR) varied systematically between 1946 and 1991. By mounting a pressure transducer on the CPR to record towing depth, it was shown, however, that changes in towing speed did not cause a significant change in towing depth, although the mean towing depth (6–7 m, SD=l-7 m, N=77) was shallower than the previously assumed towing depth of 10 m. Thus the observed changes in towing speed are unlikely to have caused discontinuities in the CPR time-series by affecting sampling depth.

Long-term data sets play an important role in attempts to understand the causes of fluctua- tions in plankton abundance. The Continuous Plankton Recorder (CPR) survey provides multi- decadal information on plankton abundance in the North Sea and North Atlantic (McGowan, 1990), and is one of the longest standing marine plankton abundance time-series. However, while the CPR time-series has great potential, as with all other data sets spanning many years, questions may be asked regarding the consistency with which the data have been collected and hence the true continuity of the time-series.

Oceanographically based mechanisms are shown to explain the spatial variation in the climatic relationship between the abundance of medusae (Aurelia aurita and Cyanea spp. of the class Scyphozoa), in the North Sea between 1971 and 1986 during June–August, and the winter (December–March) North Atlantic Oscillation Index (NAOI). A scyphomedusa population to the west of Denmark shows a strong inverse relationship between medusa abundance and fluctuations in the NAOI; the NAOI correlates strongly (P < 0.001) with both annual sea surface temperature (SST) at 6.5°E 56.5°N (1950–2008) and with winter precipitation on the Danish coast at Nordby (1900–2008) suggesting a direct link between the influence of climate and medusae abundance. In contrast, scyphomedusa abundance and distribution in the northern North Sea appears to be influenced by oceanic and mixed water inflow, which may overwhelm or mask any direct climatic influence on jellyfish abundance. Similarly, advection can also explain much of the interannual variability (1959–2000) in the abundance of other gelatinous zooplankton taxa (Cnidaria, Ctenophora and Siphonophora) in the northern North Sea as identified by the capture of gelatinous tissue and nematocysts (stinging cells) in Continuous Plankton Recorder samples. Jellyfish (Scyphozoa) in the southern North Sea may benefit from low temperature anomalies and the long-term effects of global warming might suppress Aurelia aurita and Cyanea spp. populations there. However, the biological response to temperature is complex and future research is required in this area.

The attachment capabilities of a brown seaweed, Sargassum muticum (Yendo) Fensholt were investigated in the laboratory on both smooth and rough substrata and in surging water motion reaching flow velocities of 57 cm s and 90 cm s.

Newly released zygotes have no means of adhesion until they develop rhizoids, which can adhere on contact with the substratum. Attachment tenacity, as measured by the germling's ability to withstand dislodgement at a given velocity of water flow, is slight at first, but increases with time. This is not simply a function of time spent in residence on the substratum, for germlings cultured suspension stick very quickly and tenaciously when allowed to settle. Tenacity of adhesion seems to be a reflexion of the amount of mucopolysaccharide adhesive present. This increases gradually during the first few days of the germling's life, regardless of whether it is attached or not.

Once secure attachment is achieved it is not weakened even by the death of the germling. A film of bacteria and micro algae on the surface of the substratum is not a requirement for germling adhesion, but its presence enhances the tenacity of adhesion.

Smooth substrata are the least favourable for germling survival in flowing water. On rough substrata the ‘peaks’ of the microtopography and surfaces facing into the current are much less favourable than the troughs between the ‘peaks’, or surfaces in the lee of ‘peaks’. Germling survival increases with increasing substratum roughness up to an optimum rugosity at which the mean depth of the depressions on the surface is 420 μm, and the vast majority are deeper than the height of the germlings.

Populations of Scrobicularia plana with densities up to 1025 per m2 are found in the Gwendraeth Estuary.

In a region where the population density was about 500 per m2 it was found that some specimens lived for 16‐18 years and reached a length of 54 mm. An approximate growth curve is given.

There is very little successful settlement of spat in the sampling area; less than 2% of the shells were under 10 mm in length in July 1955. This low figure is attributed to the feeding activities of the dense adult population making the area difficult to settle in.

The dominant lipids of seven species of abyssal holothurians (Oneirophanta mutabilis, Pseudostichopus villosus, Psychropotes longicauda, Deima validium, Parariza prouhoi, Amperima rosea and Molpadia blakei) have been examined in detail. Fatty acid compositions are qualitatively similar to those of shallow-water holothurians, but relatively higher amounts of unsaturated compounds in the deep sea animals are ascribed to an adaptation of the latter to maintain membrane fluidity at high pressure and low temperature. The sterol distributions of abyssal holothurians are complex, with mixtures of C26–C30 sterols being present in all of the animals. These are most likely to be dietary in origin; the holothurians substitute Δ5 with Δ7 unsaturation, via Δ5,7 or Δ0 intermediates. 14α-methylcholest-9(11)-enol, which is a common product of de novo biosynthesis in shallow-water holothurians is absent in all of the deep-water species. Furthermore, cholest-7-enol, the dominant product of de novo biosynthesis in shallow water animals, is a relatively minor component in all of the species, except A. rosea. This holothurian is also the only one that appears to assimilate 4α-methylsterols directly and contains high amounts of steryl sulphates. There are significant interspecies differences in the free sterol distributions which may reflect their different feeding strategies or niches.

Three latitudinally separated assemblages (49°–41°N, 38°–30°N, 22°–20°N in 11°–25°W) of abyssal demersal fishes in the eastern North Atlantic have been identified from combined data from 13 new and 12 previously reported trawl samples. The northerly assemblage remained unaltered by the new data, but the intermediate one could be sub-divided into shallow (4370–4475 m) and deep (4835–5440 m) elements. This sub-division revealed that bathymetry was acting with latitude to influence previous results. The new, southerly, assemblage was found below surface waters enriched by upwelling along the continental margin. The composition of dominant species identified each assemblage. The biological characteristics of these species were largely consistent with the former hypothesis linking them to the influence of the overlying production regime. The contrast between this preliminary evidence for structured demersal fish assemblages in the abyss with its lack on the slope and rise was discussed in the terms of the respective patterns of trophic input.

The galatheid crab Shinkaia crosnieri, is the sole member of the subfamily Shinkaiinae. It is abundant and forms dense beds around active hydrothermal vents in the Okinawa Trough. Thousands of filamentous bacteria attached to the plumose setae on the ventral surface of this crab were observed using field-emission scanning electron microscopy and transmission electron microscopy. Nucleic acids were extracted from the filamentous bacteria, and the phylotypes of 16S rRNA genes were identified from 81 clones. These phylotypes were divided into three groups: Epsilonproteobacteria (74%); Gammaproteobacteria (20%); and Bacteroidetes (6%). Gamma- and major phylotypes of Epsilonproteobacteria were also detected using fluorescence in situ hybridization analysis. These Epsilon- and Gammaproteobacteria were closely related to cultured and uncultured bacteria from hydrothermal vent fields including episymbionts of vent-associated invertebrates such as Rimicaris exoculata, Alvinella pompejana, the scaly-foot snail, Kiwa hirsuta etc. The carbon isotopic compositions of the muscle of S. crosnieri and in filamentous bacteria were similar. The muscle of S. crosnieri contained monounsaturated C16 and C18 fatty acids, which are known to be characteristic of sulphur-oxidizing bacteria in H2S-rich marine habitats. Through the video images transmitted by a submersible and a remotely operated vehicle, S. crosnieri was observed to comb out its ventral setae using the third maxilliped and appeared to consume the contents. These evidences suggest the epibiotic association between S. crosnieri and the filamentous bacteria attached to the ventral setae of the crab, but the details of role and function are still unclear at the present study.

1. A diving helmet can be used successfully on British coasts.

2. An ecological survey, extending to a depth of 10 feet below low water of ordinary spring tides, has been made of a small area in Wembury Bay, S. Devon.

3. Below low water of ordinary spring tides upward facing rock surfaces were occupied by a “Laminaria forest association.”

4. Below L.W.O.S.T. vertical or overhanging rock surfaces were occupied by a “Distomus-Halichondria association.”

5. Large brown Algæ are excluded from the Distomus-Halichondria association by some factor connected with the slope of the rock surface, other than inadequate illumination.

6. Freedom from silt deposition may be responsible for many of the peculiarities of the Distomus-Halichondria association,—in particular for the importance of sponges, cœlenterates, and tunicates.

7. Barnacles play an important part in the recolonisation of bare rock surfaces.

Induction of metallothionein synthesis in Littorina littorea exposed to cadmium (400 µg I-1) is tissue dependent. Concentrations of the metal-binding protein increased by a factor of four in the gills and by a factor of three in the kidney.

Gel filtration chromatography of heat-treated cytosolic extracts reveals that cadmium, accumulated in both the gills and the kidney, is bound principally to the newly formed metallothionein. Cadmium saturation of the protein (at an MT:Cd molar ratio of 1:5) and the approach of steady-state condition for Cd accumulation was indicated in the latter tissue, but there was little evidence for Cd equilibrium in gills.

Metallothionein levels in the kidney of L. littorea can be determined on a routine basis in laboratory experiments and in field samples by differential pulse polarography of wholecytosol preparations: heat-treatment/centrifugation is sufficient to remove most of the interference from high-molecular-weight thiolic proteins. In contrast, the use of gelfiltration chromatography is recommended alongside polarographic analysis of the gill cytosol to enable quantification of, and compensation for, such interferences, and hence to ensure that only metallothionein is determined.

Measurements of metallothionein induction in the kidney of Littorina may therefore prove useful in the determination of sublethal biological response to metal contamination. Background metallothionein concentrations of 3–4 mg g-1 (measured polarographically) serve as a baseline against which samples from contaminated sites can be assessed.

INTRODUCTION

Exposure of marine organisms to metals such as cadmium can induce the synthesis of low molecular weight, cysteine-rich proteins, metallothioneins (MTs), which are capable of sequestering and detoxifying excess intra-cellular metal.

The animal communities associated with the deep-sea reducing environment have been studied for almost 30 years, but until now only a single species of ophiuroid, Ophioctenella acies, has been found at both hydrothermal vents and methane cold seeps. Since the faunal overlap between vent and seep communities is small and many endemic species have been found among other taxa (e.g. Mollusca, Crustacea), additional species of ophiuroids were expected at previously unstudied sites. Chemical compositions at reducing sites differ greatly from the nearby bathyal environment. Generally, species adapted to chemosynthetic environments are not found in non-chemosynthetic habitats, but occasional visitors of other bathyal species to vent and seep sites have been recorded among many taxa except ophiuroids. This paper presents an analysis of the ophiuroid fauna found at hydrothermal vents and non-reducing nearby sites on the Mid-Atlantic Ridge and on methane cold seeps in the Gulf of Mexico, at Blake Ridge off South Carolina and south of Barbados. In addition to O. acies, four species were found at vents, Ophiactis tyleri sp. nov., Ophiocten centobi, Ophiomitra spinea and Ophiotreta valenciennesi rufescens. While Ophioctenella acies appears to be restricted to chemosynthetic areas, the other four species were also found in other bathyal habitats. They also occur in low numbers (mostly single individuals), whereas species adapted to hydrothermal areas typically occur in large numbers. Ophioscolex tripapillatus sp. nov. and Ophiophyllum atlanticum sp. nov. are described from nearby non-chemosynthetic sites. In a cold seep south of Barbados, three species of ophiuroids were found, including Ophioctenella acies, Amphiura sp., Ophiacantha longispina sp. nov. and Ophioplinthaca chelys. From the cold seeps at Blake Ridge and the Gulf of Mexico, Ophienigma spinilimbatum gen. et sp. nov. is described, likely restricted to the reducing environment. Ophiotreta valenciennesi rufescens occurred abundantly among Lophelia corals in the Gulf of Mexico seeps, which is the first record of this species from the West Atlantic. Habitat descriptions complement the taxonomic considerations, and the distribution of the animals in reducing environments is discussed.

Many reef coral diseases have been described affecting corals in the wild, several of which have been associated with causal agents based on experimental inoculation and testing of Koch's postulates. In the aquarium industry, many coral diseases and pathologies are known from the grey literature but as yet these have not been systematically described and the relationship to known diseases in the wild is difficult to determine. There is therefore scope to aid the maintenance and husbandry of corals in aquaria by informing the field of the scientifically described wild diseases, if these can be reliably related. Conversely, since the main driver to identifying coral diseases in aquaria is to select an effective treatment, the lessons learnt by aquarists on which treatments work with particular syndromes provides invaluable evidence for determining the causal agents. Such treatments are not commonly sought by scientists working in the natural environment due the cost and potential environmental impacts of the treatments. Here we review both wild and aquarium diseases and attempt to relate the two. Many important aquarium diseases could not be reconciled to those in the wild. In one case, however, namely that of the ciliate Helicostoma sp. as a causal agent of brown jelly syndrome in aquarium corals, there may be similarities with pathogenic agents of the wild coral diseases, such as white syndrome and brown band syndrome. We propose that Helicostoma is actually a misnomer, but improved understanding of this pathogen and others could benefit both fields. Improved practices in aquarium maintenance and husbandry would also benefit natural environments by reducing the scale of wild harvest and improving the potential for coral culture, both for the aquarium industry and for rehabilitation programmes.

The rate of filtering has been examined in a series of sabellids and serpulids of widely different size, using suspensions of colloidal graphite and algal cultures. The filtering rates have been expressed as individual rates, as the volume strained per unit fresh weight, and per unit weight of the crown. It may be concluded that the smaller fan worms filter at a relatively higher rate than the larger. This is achieved partly by the relatively larger crown. Free swimming algae escape through the crown; only inert particles down to 1–2 μA are retained, implying that fan worms depend on suspended detritus alone. The filtering rates are briefly compared with those of Chaetopterus and some other filter-feeding invertebrates.

The marine mussel, Mytilus edulis, is a widely distributed bivalve, especially abundant on wave washed exposed rocky shores (Lewis, 1964). Investigations on the reproductive and settlement cycles of M. edulis in Irish waters have concentrated to date on sheltered shore populations (Wilson & Seed, 1974; Seed & Brown, 1975; Rodhouse et al., 1984; McKenzie, 1986). An exception to this is a brief account of settlement in Bantry Bay (Cross & Southgate, 1983). Elsewhere in Europe, investigations on the biology of exposed-shore mussels is restricted to the extensive studies of Seed (1969) on the north-east coast of Britain.

When first described, as the type species of a new genus (Butcher, 1952), Pavlova gyrans was thought to be separable from Ochromonas by only one major character, namely the lateral instead of the supposedly terminal insertion of the strongly anisokont flagella. It was therefore natural to include it in the class Chrysophyceae and to interpret other structural features in accordance with this view. This practice has been continued to some extent subsequently and the three named species which are now recorded in the literature are all in varying degrees in need of emended descriptions. For this particular genus is deceptive. Not only are there unusual fixation difficulties, as already noted by Butcher, but even when examined alive its appearance can suggest the presence of characters which are not in fact what they seem to be and mask others which are essential for taxonomic guidance. Even when all these difficulties have been overcome, certain details are so unusual as to be without known parallel among the ‘brown’ flagellates which have so far been studied with the electron microscope.

Three species of Boccardia (B. polybranchia, B. pseudonatrix and B. proboscidea) were associated with mollusc shells on the south and south-east coasts of South Africa. Boccardia polybranchia was widely distributed along the coast and falls within the known distribution range of this species. Comparisons with material from other, international, locations showed that some specimens have been misidentified. No characters could be found to characterize distinct species for different regions within the range of B. polybranchia, as currently recognized. Boccardia pseudonatrix was found only at the most eastern site, increasing its known distribution range. Boccardia proboscidea, a non-indigenous species, was found only on abalone farms and was most abundant in the west.