The dietary compositions of Atherinomorus ogilbyi (Atherinidae), Sillago schomburgkii (Sillaginidae), Lesueurina platycephala (Leptoscopidae) and Ammotretis elongatus (Pleuronectidae) in three nearshore habitats on the lower west coast of Australia, which varied in their exposure to wave energy and the extent to which they contain sea grass, have been determined. The dietary compositions of these four abundant teleosts differed, reflecting marked differences between the location in the water column, head and mouth morphology and feeding behaviour of these species. Atherinomorus ogilbyi, which has a relatively high and large mouth, fed mainly on planktonic invertebrates in the water column, while S. schomburgkii ingested predominantly benthic prey, such as polychaetes and bivalves, which it extracted from the sediment using its downward-protruding mouth. Lesueurina platycephala employed its large mouth, cryptic coloration and ambush feeding to target relatively large teleosts and invertebrates, while the small mouth and flattened body of Ammotretis elongatus facilitated the ingestion of small crustacean prey, e.g. cumaceans and amphipods, which live on the substrate surface. Atherinomorus ogilbyi consumed predominantly calanoid copepods, cladocerans and insects during the day and mainly amphipods at night, when the latter taxon became abundant in the water column. The dietary composition of each species underwent a similar pattern of size-related change, being most pronounced in L. platycephala during the day. The diets of A. ogilbyi and S. schomburgkii, the two species for which the data were most comprehensive, differed among habitats and seasons, reflecting differences in the densities of their main prey. Comparisons between the day-time diets of the above four species with those recorded previously for a further four abundant species in the same habitats during the day, show that food resources are well distributed among the main fish species in nearshore waters along the lower west coast of Australia. This feature, together with the size-related changes in the diets of the different species, reduces the potential for inter- and intraspecific competition for food by fish species in this environment.

Reproductive aspects of Eledone moschata from the Spanish waters of the Gulf of Cádiz are reported for the first time. The species is relatively abundant over the continental shelf and it is caught as by-catch by the bottom-trawl fleet. Monthly samplings throughout one annual life-cycle showed a sex ratio with a female dominance (0·45:1). A four stage maturity scale was used for both sexes. The reproductive period was determined from monthly evolution of these stages as well as that of several maturity and condition indices. The breeding season extended from October to June, with spawning peaks in October and March–May, the second one being more important. Length and weight at maturity (mantle length50, body weight50) were estimated at 7·8 cm and 97 g in males, and at 12·2 cm and 274 g in females, respectively. Total fecundity, estimated from 52 mature females, was 443·5±154·4 oocytes on average. The mean size of mature oocytes and the mean length of mature spermatophore in mature females and males was 10·24 mm (±1·07) and 13·88 mm (±1·60), respectively.

Using data available from the literature, patterns of biomass, production and productivity of sandy-beach macrofauna populations were examined, considering environmental (temperature, exposure, grain size and beach slope) and biological variables (life span and mean body mass) and feeding and taxonomic groups. A total of 102 estimates of both production and biomass and 105 estimates of P/B ratios were collected from 52 studies carried out between 42°46′S and 54°05′N, for 83 sandy-beach macrofauna populations. The negative relationship between P/B ratio and beach slope for the supralittoral amphipods agrees with the Habitat Safety Hypothesis, according to which these forms would show higher mortality in dissipative than in reflective beaches. The observed higher production of filter-feeders in exposed than in sheltered beaches suggests that more food is available for filter-feeders in exposed beaches. The higher production of filter-feeders (represented by bivalves and decapods), than of scavengers/predators (peracarids and gastropods) showed the importance of filter-feeders in the food web of sandy beaches. The P/B ratios were strongly related to life span, but weakly or not related to the mean body mass. The high amphipod P/B ratio was attributed to the short life span of these crustaceans; conversely, gastropods showed the lowest P/B ratio, in accordance with their longer life span. The observed differences in biomass, production and P/B ratios within crustaceans and molluscs were attributed to differences in life-history traits and feeding mode.

A series of field and laboratory experiments were conducted in order to assess whether the burrow-dwelling amphipod Corophium volutator, is a significant bioturbator of inter-tidal mud and sand flats where it often occurs at densities of tens of thousands per square metre. Comparisons of sediment characteristics, redox potential and meio- and macro-faunal populations in treatments with enhanced, natural and reduced densities of Corophium revealed effects on sediment physico-chemistry and on small meiofaunal-sized species, but these were weak and not always consistent. High densities of adult Corophium consistently depressed the abundance of smaller conspecifics although the mechanism of this interaction has not been identified. The results are discussed in the context of the ability of Corophium to promote the recovery of organically enriched sediments.

1. The nauplius stages of three species of Longipedia are described, and the segmentation and armature of the appendages of L. coronata are given in tabular form.

2. The main features in the external structure of the copepodite stages are summarised in a table.

3. Additional points of resemblance between the nauplii of Longipedia and the cirripedes are presented.

4. Notes are given on breeding and development under laboratory conditions ; there is no evidence of parthenogenesis.

5. Feeding in the copepodite stage of Longipedia is described.

6. A description is given of the hitherto unknown male form of L. scotti.

Back-calculated egg fertilization (spawned) dates and growth rates for young-of-the-year bass, Dicentrarchus labrax (L), captured from Loughor Estuary, Oxwich Bay and Ogmore Estuary, south Wales, UK, during 1988 and 1989 were compared. Spawned date frequency distributions indicated that the bass spawning season began in late February and continued until early June in 1988 and early July in 1989.

There were no significant differences in the frequency distributions of back-calculated spawned dates for the bass populations, between either sites or years, which suggested that any variations in growth rates were attributable to characteristics of their respective environments. Growth rates were determined for bass cohorts resulting from early, midor late-season spawnings at Oxwich and Loughor in 1988 and Oxwich, Loughor and Ogmore in 1989. There were only slight intra-annual differences between the mean growth rates of bass cohorts at the same site, suggesting that bass from early cohorts would be larger at any given time of year. In 1989, growth was considerably faster at Oxwich and Loughor than at Ogmore, where food supply was considered limiting. However, between-site variations in growth rate were small in comparison with inter-annual differences. The faster growth rates observed at Loughor and Oxwich in 1989 were attributed to higher water temperatures.

Relationships between growth rate and subsequent survival of young-of-the-year bass, and the relative importance of estuaries as nursery habitats for juvenile bass, are discussed.

This study examined the trophic ecology of the zoanthid Palythoa caribaeorum in tropical reefs and evaluated its role in the energy flow in that ecosystem. Colonies of this species were sampled in the infralittoral zone of reefs in north-eastern Brazil in 2008. We calculated the richness, total abundance, relative abundance and frequency of occurrence of prey items. The biovolumes and weighted biovolumes of prey were calculated to characterize the most important food items in terms of their biomasses. To evaluate the selectivity, zoanthid and plankton samples were collected in 2010. Pennate diatoms were the most abundant and most frequent prey and, together with invertebrate eggs, constituted the most important food items in terms of their biomasses. There were no significant differences in abundance or richness among the different beaches studied, nor between the different seasons. The mean size of prey items within the polyps was significantly smaller than of the general plankton, indicating that P. caribaeorum selected for (or limited) certain prey sizes. This species predominantly fed on diatoms, and did not take advantage of many other prey items abundant in the plankton. Our results indicate that P. caribaeorum is suspensivorous and feeds principally on small phytoplankton. As this species is prey for benthic organisms such as polychaetes and nektonic organisms, our results indicate the importance of this zoanthid in tropical reef ecosystems as a primary consumer that serves as an energy transfer link between the planktonic environment and the nektonic and benthic spheres.

Aspects of the population dynamics of the undulate ray, Raja undulata (Chondrichthyes: Rajidae), one of the more abundant elasmobranch fish captured along the Portuguese south coast (Algarve), were studied for the first time. Some traditional elasmobranch vertebral enhancing techniques were compared and the most precise for this species determined to be the cedar wood oil immersion and the alizarin red S stain. The sample consisted of 14 age-classes, with age-classes 3 to 8 being the most represented. Evidence of an annual deposition pattern of a pair of bands (one opaque and one translucent) was found by marginal increment analyses. Von Bertalanffy growth parameters were estimated and no differences found between males and females (all data: Linf=110·22 cm, K=0·11 y−1 and t0=−1·58 y).

The European sea-urchin, Echinus esculentus L., occurs from Finnmark in the north to the Canaries in the south. Around Britain, it is found from the Isle of Portland, English Channel, throughout most of the fully saline waters of the western and northern coasts, and in the North Sea as far south as Flamborough Head. Though it occurs between tide-marks in a few places, it is generally common from about 5 m depth below c.d. to about 100 m, though it is recorded from about 200 m depth (A. M. Clark, personal communication). It is a principal browser on the reefs on which it occurs, and feeds preferentially on kelp sporelings and other algae when it occurs in the photic zone, and on encrusting invertebrates and protochordates below the depth at which algae occur (De Ridder & Lawrence, 1982). E. esculentus is said to migrate inshore prior to spawning, and then retreat to deeper water in late spring (Elmhirst, 1922; Stott, 1931; personal observation), but a rigorous study of these apparent movements has yet to be undertaken. Echinoids fare better on a diet principally of algae than on one of animal material (Lawrence, 1975), so it might be assumed that the winter inshore migration could bring an urchin into a nutritionally richer area for the final developmental phase of gametogenesis.

Apart from a general account (Kon, 1954) of our work on vitamin A and carotenoids in invertebrates, our publications so far (Kon & Thompson, 1949a, b; Batham, Fisher, Henry, Kon & Thompson, 1951; Fisher, Kon & Thompson, 1951, 1952, 1953, 1954, 1955) have been concerned only with marine Crustacea. We have also studied, during our investigation of the metabolism of vitamin A and its possible precursors in the sea, numerous species from most other phyla of marine invertebrates. Except for the nematode worm, Anisakis physeteris Baylis, taken from the stomach of a sperm whale, the only two phyla of invertebrate animals in which we have so far found vitamin A are the Arthropoda and the Mollusca. The vitamin was present in at least some species from each of the molluscan classes, Loricata, Gastropoda, Lamellibranchiata and Cephalopoda, but we have no information yet about the Solenogastres or the Scaphopoda of which we have analysed no representatives. So far as our studies were concerned, the cephalopods differed considerably from the other molluscs examined, and the relatively large amount of information they have provided will be more conveniently presented in a subsequent paper. The account which follows, therefore, deals only with species from the first three classes just listed.

In Florianópolis, southern Brazil, the venerid clam Anomalocardia brasiliana has supported subsistence and small-scale commercial fisheries for decades. The introduction of a hand dredge (gancho) since 1987 led to the development of a significant fishery supplying both local and regional shellfish markets. In 1992 one of the main fishing areas in the region was designated as the first Brazilian Marine Extractive Reserve (Pirajubaé RESEX), a federal form of governance intended to promote sustainable exploitation of natural resources by assigning exclusive fishing rights to traditional users. However, excessive fishing effort, institutional shortcomings and lack of a negotiated management plan have resulted in the overexploitation of the species since 2000. This study was aimed at evaluating the efficiency and selectivity of the hand dredge currently in use at the RESEX, through a field experiment conducted in October 2006. Quantitative samples of A. brasiliana were collected before and after dredging 15 experimental plots. Additional samples were obtained inside the dredge (catch) and respective cover cod-end (discard) for selectivity analysis. A single haul of the hand dredge can dislocate up to 76% of the individuals present in the sediment irrespective of their size, and retain up to 69% of the commercial-sized organisms. The gear has a knife-edge selection pattern, which enables the use of the minimum spacing between the iron bars of the dredge's basket as an effective management tool.

The overall biotic pressure on a newly introduced species may be less than that experienced within its native range, facilitating invasion. The brown alga Sargassum muticum (Yendo) Fensholt is a conspicuous and successful invasive species originally from Japan and China. We compared S. muticum and native macroalgae with respect to the biotic pressures of mesoherbivore grazing and ectocarpoid fouling. In Strangford Lough, Northern Ireland, S. muticum thalli were as heavily overgrown with seasonal blooms of epiphytic algae as native macroalgal species were. The herbivorous amphipod Dexamine spinosa was much more abundant on S. muticum than on any native macroalga. When cultured with this amphipod, S. muticum lost more tissue than three native macroalgae, Saccharina latissima (Linnaeus) Lane et al., Halidrys siliquosa (Linnaeus) Lyngbye and Fucus serratus Linnaeus. Sargassum muticum cultured with both ectocarpoid fouling and amphipods showed a severe impact, consistent with our previous findings of large declines in the density of S. muticum observed in the field during the peak of fouling. Despite being a recent introduction into the macroalgal community in Strangford Lough, S. muticum appears to be under biotic pressure at least equal to that on native species, suggesting that release from grazing and epiphytism does not contribute to the invasiveness of this species in Strangford Lough.

A survey of publications and collections databases reveals a pattern of non-indigenous decapods distribution in the 13 seas around Russia and adjacent countries. No alien species were reported from Russian territorial waters and exclusive economic zone in the Japan, Okhotsk, west Bering and most of the Siberian shelf Seas. From the seas and their basins in East Europe, 13 alien species have been recorded, with seven of these yet to become established. Established or commonly occurring species can be categorized as: ‘global invaders’ (Chinese mitten crab, Eriocheir sinensis in the White, Baltic, Black, Azov and Caspian Seas; and Harris mud crab, Rhithropanopeus harrisii in all mentioned seas, except the White Sea); ‘regional aliens’ (Palaemon adspersus and P. elegans in the Caspian Sea and the latter species in the Baltic); and ‘Arctic invaders’ (Kamchatka king crab Paralithodes camtschaticus and snow crab Chionoecetes opilio). Eriocheir sinensis is the most widely occurring alien decapod species, but there are no indications of an established population in East Europe. For this and other mentioned crab species, invasion history, distribution and important biological data are reviewed. In the seas where few or no native crab species have been present, Harris mud crab (in the Azov and Caspian Seas), Kamchatka crab (in the Barents Sea) and snow crab (in the Barents and Kara Seas) have shown rapid establishment (within two decades) of an invasive population throughout an entire basis or its significant part.

Samples of the deep-sea forcipulate seastars Brisinga endecacnemos, Brisingella coronata, Freyella spinosa and Zoroaster fulgens have been collected at a number of stations in the N.E. Atlantic. Examination of their reproductive biology suggests subtle interspecific variations in their gametogenic cycles. The gonads of Brisinga endecacnemos are serially arranged under the dorsal arm surface, each cluster of gonad tubules having its own gonopore. In the closely related Brisingella coronata each gonad consists of up to 12 elongate tubules opening at a single gonopore at the dorsal surface. In both species the maximum egg diameter is about 1250 μm and fecundity may be up to 60000 eggs per individual. It appears that the eggs in Brisinga endecacnemos are produced in clusters whilst those of Brisingella coronata are produced continuously. InFreyella spinosa the gonad consists of a small tubular sac analogous to a single tubule of Brisinga endecacnemos. Maximum fecundity is only 2500 eggs per individual, and the maximum egg size is 1250 μm. In all three species eggs that are not spawned undergo internal oocyte degeneration. The gonads of Zoroaster fulgens show the typical asteroid configuration of two at the base of each arm, one either side of the ambulacrum. The maximum oocyte diameter is 950 μm. There is some evidence that there may be a seasonality of reproduction in this species. In all four species examined the large egg size and relatively low fecundity suggest direct demersal development with the subtle variations in their reproductive biology reflecting slightly different breeding habits.

This paper presents baseline information on maternal behaviour and lactation in the Mediterranean monk seal, with particular focus on the age at which pups are weaned. The study was conducted in the western Saharan population, the only surviving colony of the species. The first moult finished at a mean pup age of 72.3±17 d (N=17) and, in contrast to other taxonomically-related phocids, this process was not associated with weaning. Lactation lasted a mean of 119.4 d (N=9; range: 103–149 d) in the pups that could be monitored until full weaning had taken place. This period almost doubles the maximum lactation length reported in other phocid species. During the first week after birth the mother–pup bond was well developed and mothers always remained with their pups. The time invested in nursing (17%, SD: ±36) and in mother–pup interactions (14%, SD: ±32) was higher during this period than afterwards (8%, SD: ±23 and 4%, SD: ±19, respectively). After the first week, nursing continued but mothers started to leave their pups in order to feed at sea. Weaning occurred gradually. Already since birth, pups were active and mobile, and swam frequently before moulting or weaning occurred. Fostering and milk stealing were common patterns of behaviour for both lactating females and pups. In 26.6% of the suckling episodes observed in mother–pup pairs of known identity, pups suckled from females other than their mothers. Some females nursed more than one pup, at least occasionally, and in some cases a pup was fostered long-term by an alien female. The Mediterranean monk seal exhibits maternal-care characteristics that are more like otarids than phocids. This observation contradicts previous proposals that a short lactation period is a phylogenetic characteristic of phocids. Several of the unusual maternal traits observed may be favoured by year-round access to abundant food supply, availability of breeding sites, and mild climatic conditions. This information should be taken into account when designing conservation strategies for the species and, very particularly, in the implementation of pup rehabilitation programmes.

The Solent European Marine Sites contain many tiers of habitat and species conservation, but also high levels of bait collection. Effective management strategies must be founded on up-to-date and locally based information from relevant studies of the impacts; these have been lacking for the collection of Nereis virens, a key bait species. The impacts on macrofauna were assessed through two approaches; (a) undug and dug sites in the Solent were compared over two years of repeat sampling; and (b) monitoring the long-term effects of simulated bait collection at an undug site through five years of yearly sampling. Dug sites had significantly higher densities of N. virens, but the mean weight was found to be significantly lower than those collected from the undug sites, but percentage maturity was not different. Organic content and sediment particle sizes differed between sites, and only the presence of gravel had a significant positive correlation with density. No clear patterns of other macrofauna species present were evident, although there was a significantly lower density of the terebellid polychaete Neoamphitrite figulus at the dug sites. Simulated bait collection did not alter overall macrofauna diversity, but certain species were affected. Abundance of N. figulus and the commensal Harmothoë glabra remained consistently lower in the dug area, whilst Cerastoderma edule numbers were reduced initially, but recovered. Numbers of Nephtys hombergii declined in both areas, but at a significantly greater rate in the dug area. A general decline in the abundance of many species, irrespective of digging, occurred over the period. The importance of these changes in Nereis virens populations and in the macrofauna community needs to be investigated prior to any management decisions on collection.

Ostrea edulis was extremely rare in the wild in Strangford Lough from the early 1900s until renewed spatfall was observed at a number of sites in the 1990s. A monitoring programme was undertaken to investigate the presence and distribution of planktonic oyster larvae at nine sites around the lough between June and September in 1997 and 1998 as a precursor to studies of spatfall patterns. Larval densities at sites in the northern basin of the lough were significantly higher than those in the southern basin where larvae were lacking or in low numbers. Densities and sizes of oyster larvae showed significant temporal variation suggesting pulsed larval release. Larval densities also showed significant spatial variation with higher densities at sites closer to commercial stocks pointing to these as the main source of oyster larvae. This hypothesis was supported during a larval flux study over a complete tidal cycle which indicated a 90% net tidal movement of O. edulis larvae from the entrance of the bay where commercial stocks were held to the main body of the lough. Thus the maintenance of dense commercial stocks of flat oysters may provide the key to the redevelopment of native oyster beds in Strangford Lough and elsewhere by providing an initial broodstock nucleus from which larvae can be exported.

The behaviour of two ectosymbiotic animals, Peregrinamor ohshimai (a bivalve attached to the ventral cephalothorax of the host), and Phyllodurus sp. (a bopyrid isopod attached to the second pleopod of the host), during ecdyses of the host thalassinidean Upogebia shrimps was studied by time-lapse video of infested shrimps. In the intermoult stages of the hosts, both ectosymbionts did not move. However they moved on to the newly emerged body of the host at the time when the host moulted. Peregrinamor ohshimai began to move just after the host started moulting, whereas Phyllodurus sp. moved prior to ecdysis of the host and waited near the fissure from which the newly moulted body emerges first. There are highly correlated morphological relationships between the symbionts and the hosts. It is suggested that both ectosymbionts grow with the same host individuals after infection, keeping morphological affinity with their hosts without being discarded during ecdyses of the hosts.

The evolution of a Phaeocystis bloom off Plymouth in spring 1990 is described. Data were obtained (1) during weekly visits to station El to measure physical parameters, nutrient concentrations, primary production and grazing pressure and (2) by regular tows of an Undulating Oceanographic Recorder around a circuit of five stations including El to detect stratification, monitor the geographical distribution of chlorophyll and determine vertical profiles at each station.

The data show that the Phaeocystis bloom emanated from near-shore, its spread towards the south-east correlating with the wind direction prevailing at the time. Due to bad weather, seasonal stratification had not been established at the time of the bloom so that a major diatom outburst had not occurred and nutrients remained high as the Phaeocystis moved offshore.

Zooplankton populations at El, averaged over 50 m, decreased whilst Phaeocystis was present, resulting in very low grazing pressure. Termination of the bloom was not, therefore, due to consumption by herbivores. It was, instead, caused by Phaeocystis colonies becoming nutrient-depleted and releasing single cells which were transported downwards. As a result of this, chlorophyll concentrations near the bottom remained high for some time after the Phaeocystis had disappeared from the surface water.

A scenario is proposed to explain the observations in terms of our current understanding of the ecophysiology of Phaeocystis.

The scorpaenid Maxillicosta scabriceps (Teleostei) and the platycephalid Platycephalus longispinis (Teleostei) were trawled seasonally for a year from shallow (5–15 m) and deeper (20–35 m) waters in four distantly-located regions of the inner continental shelf of south-western Australia. The former species was more abundant in southern regions, which is consistent with its temperate distribution, while the latter species was more abundant in deep than shallow waters. Unlike M. scabriceps, P. longispinis with total lengths < 110 mm were rarely caught, indicating that this latter species only moves on to the sandy substrate of the inner shelf when it reaches a certain size. As M. scabriceps increased in size, the contributions of mysids, amphipods and oxyrhyncan crabs to the diet declined, while those of carid decapods and brachyrhyncan crabs increased. The invertebrate fauna ingested by the smallest length-class of P. longispinis, 110–139 mm, was similar to that of the same and largest length-class of M. scabriceps. However, unlike M. scabriceps, this length-class of P. longispinis consumed teleosts, despite having a relatively smaller mouth. The contribution of teleosts subsequently increased as P. longispinis increased in size, a feature reflected by the relatively low dietary breadth of large fish. The marked shift in the types of prey ingested by P. longispinis as it increased in size accounted for the fact that, in contrast to M. scabriceps, there was limited dietary overlap between the larger and smaller members of this platycephalid. The ability of P. longispinis to ingest other fish is presumably related to the fact that platycephalids lie just under the substrate surface and are thus concealed from their potential prey, and that they are able to emerge rapidly and pursue their prey.