Male and female sharknose cleaning gobies Elacatinus evelynae (Gobiidae) occupying cleaning stations in monogamous pairs differed significantly in cleaning behaviour and diet. Females spent five times longer cleaning, took more bites from clients, engaged in more cleaning events on more client species, and cleaned at a higher rate than males. These behavioural differences tended to be reflected in the diet, with more females ingesting more client-gleaned items than males. These results are consistent with greater energetic requirements for reproduction for females. Male cleaning gobies were frequently absent from cleaning stations, presumably guarding eggs, and their presence at cleaning stations gave rise to foraging conflicts and interactions with females. The cleaning rate of females was significantly lowered by the presence of males, whether cleaning or not, whereas males cleaned for longer and took more bites when females were present. When cleaning the same client, males and females showed priority of first inspection, with females cleaning longer and taking more bites in cleaning events they initiated while males gained similar advantages in client- and male-initiated interactions. Furthermore, females initiated cleaning on larger clients, which may give them a foraging priority on a higher-quality resource since larger clients tend to have more ectoparasites. Finally, from a client's perspective, the cleaning service provided appears better in terms of length of inspection and bites taken when both males and females are at a cleaning station than when a single cleaner is present. However, the foraging differences and interactions between male and female cleaning gobies are of little consequence to clients since the cleaning service provided is simply reapportioned between males and females rather than changed by the interactions between gobies.

Contaminants causing sex-altering, endocrine disrupting-like (ED) effects, or otherwise influencing reproduction, have been of growing concern to humans for more than 50 years. They have also been a perturbing, though less well-studied, phenomenon in marine organisms, following the recognition of tributyltin (TBT)-induced imposex and population extinctions in (neo)gastropods in the 1970s. Whilst ED impacts in mammals and fish are characterized by mimicry or antagonism of endogenous hormones by environmental contaminants (acting through Nuclear Receptors which are present in all metazoans) much less is known regarding pathways to effects in invertebrates. Despite the absence of a defined steroidal/mechanistic component, the extent, severity and widespread nature of ED-like manifestations and altered sexual characteristics observed in marine invertebrates gives rise to comparable concerns, and have been a long-term component of the MBA's research remit. The manifestations seen in sensitive taxa such as molluscs and crustaceans confirm they are valuable indicators of environmental quality, and should be exploited in this capacity whilst we seek to understand the pervasiveness and underlying mechanisms. In so doing, invertebrate indicators address aims of organizations, such as the EEA, OECD, UNEP and WHO, charged with management and monitoring of chemicals and ensuring that adverse effects on humans and the environment are minimized (Bergman et al., 2013). In view of the recent general declines in marine biodiversity, and the potential contribution of ED-like phenomena, safeguarding against deleterious effects through increased research which links pollutant exposure with reproductive dysfunction among invertebrates, is seen as a high priority.

1. Phosphoric acid in sea-water may be determined with an accuracy of about 0-003 mg. per litre by concentration with iron and colorimetric examination.

2. If the sea-water be previously oxidised by potassium permanganate the amount found is considerably increased.

3. From September, 1915, to February, 1916, the average amount of phosphoric acid in water collected half a mile outside Plymouth Break-water was 0-044 ing. per litre ; this showed signs of an increase when the supply of land-water rose after rain. The figures are much lower than those found by Raben for the Baltic and North Sea.

4. The amounts found by another method during the previous spring and summer are higher, but the figures cannot be considered quite trustworthy.

From 1964 to 1967, 163 deep-sea fish have been caught from 28 line hauls in depths of from 1000 to 3300 m. Slightly over half the total catch consisted of elasmobranchs. The largest individual fish was a shark Pseudotriakis microdon of 2·25 m length taken from 1400 m. The distribution of the eleven species taken regularly in these and previous hauls is compared and contrasted.

Prior to moulting, the preadult Lepeophtheirus pectoralis produces a temporary frontal filament which attaches the animal to the surface of the host during ecdysis. This filament is extruded from a frontal organ previously thought to have a chemoreceptory function. During ecdysis the exuvium splits at the anterior margin and is shed posteriorly by contractions of the body. After hardening of the exoskeleton the copepod detaches itself from the frontal filament and is free-living on the host during intermoult. Males in precopula position hold on to the dorsal side of the female, with the second antennae grasping the anterior end of the female's genital complex. During the ecdysis of the female, most males release their hold on the female, and are usually found close to her on the host. Copulation occurs between an adult male and an adult female with a hardened exoskeleton. In the copula position the male holds on to the female's genital complex with the second antennae, but now on the ventral side of the female. Two spermatophores are extruded and then transferred simultaneously to the female with the aid of the second pair of swimming legs. Tubes originating from the spermatophores connect them to the orifices of the receptaculum seminis. These tubes seem to grow out of the spermatophores after expulsion. After copulation, the male retains a precopula position before releasing the female. No agonistic behaviour has been observed between a precopulating/copulating male and additional males. However, during the ecdysis of the female, a new male may take over the female, but mating does not seem to be assortative for size in Lepeophtheirus pectoralis.

During observations on the development of the eggs of Calanus finmarchicus the process of hatching was watched on many occasions. Since it differs from that described by Ziegelmayer (1926) for cyclopids it seemed worth while examining the process in other groups of copepods as well.

Hatching can be followed very easily in Calanus (Pl. I). For some time before, the form of the nauplius can be clearly seen with its limbs folded close to the body (A); in many a red pigment spot develops at this time in the otherwise transparent egg. Shortly before hatching the limbs begin to twitch occasionally and a space is just visible round the body of the nauplius. At this stage the inner and the outer egg membranes cannot be distinguished, but when hatching begins, the outer membrane must crack for the delicate inner membrane bulges out (B). The bulge enlarges rapidly (c), and the nauplius extends into the bulge, sometimes leaving a clear space between itself and the membranes (D). Usually it is either the head or the tail end which pushes into the bulge, but occasionally it is a limb. Probably it is abnormal for a limb to extrude first since such eggs do not always hatch successfully. As the inner membrane expands, the outer slips back and the inner, enclosing the nauplius, pops out (E). This emergence often occurs suddenly, but sometimes it is gradual (as in E), when the outer membrane crumples up on the inner, regaining its original shape only when the inner has slipped out and the tension is released (F).

In a field survey and a field experiment the relative importance of host size and temporal exposure in determining metacercarial infection levels in an intertidal bivalve was investigated. While cockles (Cerastoderma edule) of different age (indicated by winter rings on shells) collected at the same site showed strong positive correlations between host size and infection levels over the total sample, correlations were weak or absent within the age groups. Mean infection levels in cockles strongly increased with age suggesting temporal exposure and not size to be the main determinant of infection levels in the cockles. This was supported by a field experiment in which small and large cockles were exposed for one or two months on a tidal flat. While infection levels significantly increased with temporal exposure, host size had no significant effect. This suggests that bivalve hosts on temperate tidal flats accumulate parasites during a distinctive infection window during summer more or less independent of their size. With every additional year of exposure, infection levels of the parasites increase. Hence, it is important to take host age into account when comparing individual infection levels within and among different host populations.

The researches here described extended for intermittent periods over the years 1906 and 1907, and were primarily intended to embrace inquiry into the food problem of Pilchard, Herring, and Mackerel frequenting the western part of the English Channel. The observations now recorded form, therefore, a part of a wider series.

Phylogeography and population genetic studies in the Porifera have been limited by the lack of available polymorphic DNA markers. In this paper, we tested four new mitochondrial markers in nine demosponge species from a wide taxonomic range: partial sequences of the ATP synthase 6 (ATP6) and the cytochrome oxidase 2 (CO2) genes and two spacers: one located between ATP6 and CO2 and the other between the NADH dehydrogenase subunit 5 (ND5) and the small subunit ribosomal RNA (rns) genes. The new markers presented levels of nucleotide diversity up to 2.4 times higher (π = 0.015 for CO2) than those observed for the most commonly used mitochondrial marker in sponges, the cytochrome oxidase 1 gene (π = 0.006), making them suitable for alpha-level systematics, phylogeography and population genetics studies. 

A chromatographic/fluorcmetric method was used to measure changes in the proportions of four planktonic dihydroporphyrin pigments during the spring bloom of 1979 in two f jordic sea-lochs, Creran and Etive, on the west coast of Scotland. Very little pheophytin a was detected during the bloom. Chlorophyll a, and to a lesser extent chlorophyllide a, were the two main pigments found during the bloom. During senescence the main pigment breakdown route appeared to be via chlorophyllide a to pheophorbide a. These results suggest that standard methods for measurement of ‘chlorophyll’ which do not distinguish between chlorophyll a and chlorophyllide a might significantly over-estimate the photosynthetic potential of phytoplankton.

INTRODUCTION

Amoebae of the genus Paramoeba Schaudinn, 1896, are among the Gymnamoebia most frequently isolated from marine habitats, and individual species have a wide distribution throughout the world. Unlike many genera of Gymnamoebia, Paramoeba is exclusively marine. The type species, P. eilhardi Schaudinn, 1896, was originally described from a marine aquarium in Berlin with no further information on origin (Schaudinn, 1896); it has been found in the Mediterranean off France (Chatton, 1953; Grell, 1961) and Italy (Grell & Benwitz, 1970) and the Indian Ocean off Madagascar (Grell & Benwitz, 1970). P. schaudinni de Faria, da Cunha & Pinto, 1922, originally described from a sea-water aquarium at Rio de Janeiro, has recently been reported from the Gulf of Mexico (Sawyer, 1980). P. pemaquidensis Page, 1970, has been found on the coasts of Maine, U.S.A. (Page, 1970), Norfolk (Page, 1973), and Essex (Page, unpublished); in open waters off the eastern coast of the U.S.A. (Davis, Caron & Sieburth, 1978); in marine sediments of the western North Atlantic, the Bight of New York, and the Gulf of Mexico (Sawyer, 1980); and in the present study on the shores of North Wales and western Scotland. Paramoeba aestuarina Page, 1970, though not found as often as P. pemaquidensis, is also widely distributed (Page, 1970; Davis et al. 1978; Sawyer, 1980). The first European finding of P. aestuarina is reported in the present paper, but the exact origin of the strain is uncertain. P. perniciosa Sprague, Beckett & Sawyer, 1969, which appears to be an obligate parasite, has thus far been reported only from crustaceans off the eastern coast of the U.S.A. (Sprague, Beckett & Sawyer, 1969; Sawyer, 1976).

Virus-like particles were observed in thin sections of partially bleaching colonies of the scleractinian Acropora cytherea, collected in the Hon Mun Marine Protected Area (Vietnam). The most common particles were found in the cytoplasm of epidermal cells, exhibiting icosahedral symmetry and measuring 90–140 nm in diameter. Some had a tail-like structure resembling that of certain Hepadnaviridae such as the hepatitis B virus. Some others were tailless with a virion size. Overall, less than 10% of the cells showed obvious signs of infection. Images of virally-parasitized tissues of A. cytherea provide further evidence that corals are a target for viral infection. However, more research is required into their pathogenicity and involvement in bleaching events.

Two new species of lithistid sponges, Gastrophanellaphoeniciensis sp. nov. (Siphonidiidae) and Microscleroderma lamina sp. nov. (Scleritodermidae) are described from a submarine cave, depth 2–3 m, in Lebanon. They are the first Mediterranean records of two genera with a mainly tropical distribution, Gastrophanella being known from the western Atlantic (Caribbean, Brazil), central eastern Pacific (Mexico) and South Africa, and Microscleroderma from the Indo-Pacific and the eastern Atlantic (Senegal). They are interpreted as remnants of a warmer period in the Mediterranean that survived the subsequent cooling only in the warmer eastern basin. Gastrophanella phoeniciensis sp. nov. is closely related to G. cavernicola from Brazil and Belize, from which it differs essentially in its shape. Microscleroderma lamina sp. nov. is characterized by a lamellar shape, short oxeas and having hair-like oxeas arranged around the aquiferous openings.

Information on the littoral fauna of Rockall (lat. 57° 36′ 20” N, long. 13° 41′ 32” W) is limited to the report by Crisp (1956) on a collection made during the occasion of the annexation of Rockall to the British Crown in 1955. An historical survey (Fisher, 1956) reveals that only once previously has a marine biological (phycological) collection been taken from the rock, during a landing from the French’ Pourquoi-Pas ?’ in 1921 (Charcot, 1921; Hamel, 1922).

Scale readings from 6269 bass caught in 1946–86 on various parts of the U.K. coast, with a few from the Channel Islands and France, have been analysed to determine U.K. growth patterns and assess the relative abundance of successive year-classes. In the U.K. growth was fastest on the south-east coast, slowest on the west coast. In the Channel Islands growth was initially slower than on the south-east coast but faster after maturity; though less fast than on the Biscay coast of France. Year-classes of exceptional abundance tended to grow more slowly than classes of normal abundance. There was evidence in each region of a slight long-term fall in growth rate. Best growth occurred in warm summers. The growth period commenced, and annulus formed, at dates ranging from early May for the youngest juveniles to mid July for adults; terminating in each case in October. Males grew rather more slowly than females and appeared less long-lived and less hardy, except on the south-east coast, where, exceptionally, samples were caught well offshore and included large, generally faster growing fish; this suggests a behavioural difference between the sexes rather than consistently slower growth in males. Explanations are offered for occasional fast growing fish, which occur mainly on the south-east coast and mainly with particular year-classes, notably 1966 and 1969. Problems of interpretation are considered and solutions offered.

In species that aggregate for reproduction, the social and fitness costs of movement between groups frequently lead to restricted exchange between breeding areas. We report on four individual humpback whales identified in both the Cape Verde Islands and Guadeloupe; locations separated by an ocean basin and >4000 km. This rate of exchange is rarely encountered between such geographically discrete breeding areas. Two individuals returned to the area where they were originally identified. In contrast, no individuals from the Cape Verde Islands were resighted to the much larger sample from the Dominican Republic, though the migratory distances from the feeding areas are comparable between these areas. The social factors driving the stark difference between groups that is observed here are not clear. Effective conservation requires an understanding of the extent and pattern of movement between population units. The findings presented here suggest that there may well be more than one behaviourally distinct group within the West Indies. More broadly, they argue that considerable caution is warranted in assumptions made regarding the number, boundaries and status of population units based solely on spatial separation or proximity.

Monthly sea temperatures are tabulated for Station E1 from 1960 and for Plymouth Sound from 1958. The 70-year series now available shows that annual means increased by 0·75°C up to the 1950s. Since 1960 inshore temperatures have fallen 0·5°C and E1 surface temperatures 0·4°C. Sea-bottom temperatures at E1 increased 0·4°C between 1920 and the 1950s, and have fallen 0·4°C since 1960. The changes have been most marked in the second half of the year, but the last quarter (October-December) is still somewhat warmer than in 1920 and earlier.

The phylogenetic position of Xenoturbella spp. has been uncertain since their discovery in 1949. It has been recently suggested that they could be related to Ambulacraria within Deuterostomia. Ambulacraria is a taxon that has been suggested to consist of Hemichordata and Echinodermata. The hypothesis that X. bocki was related to Ambulacraria as well as the hypothesis of a monophyletic Ambulacraria is primarily based on the analysis of DNA sequence data. We tested both phylogenetic hypotheses using antibodies raised against SALMFamide 1 and 2 (S1, S2), neuropeptides isolated from echinoderms, on X. bocki and the enteropneust Harrimania kupfferi. Both species showed distinct positive immunoreactivity against S1 and S2. This finding supports the Ambulacraria-hypothesis and suggests a close phylogenetic relationship of X. bocki to Ambulacraria. In particular, the presence of immunoreactivity against S2 can be interpreted as a synapomorphy of Enteropneusta, Echinodermata, and Xenoturbella spp.

In this study, the stomach contents of 116 albacore specimens, Thunnus alalunga were examined from the eastern Mediterranean Sea. Fifty-five of the 116 stomachs examined were empty. The occurrence of major prey categories in stomachs were 95.1% cephalopods, 47.5% teleosts and 39.3% crustaceans with a total of 633 individuals belonging to 14 species identified. Heteroteuthis dispar from the order Sepiolida constituted 56.40% of the main cephalopod prey followed by Onychoteuthis banksii from the order Teuthida.

Passive acoustic monitoring of common dolphins was conducted across a survey area of 1000 n.m.2 (nautical miles) off the west Wales coast during the months September, October, November and December 1995. Dolphin presence and distribution was assessed by a system of percentage acoustic contact. Results were compared with those from a seismic/dolphin survey during the same months of the previous year, and across the same survey area. Distributions of common dolphins within the survey area showed similar trends for both years, with a marked decrease in dolphin contacts between September and October of both years. These observations suggest offshore migration of common dolphin populations at the time of year. Sea surface temperature distribution across the entire region was visualized during two survey periods using infrared satellite imagery. It is hypothesized from these observations that offshore migration of common dolphins coincides with a break-up of the Celtic Sea Front, a distinct oceanographic feature which crosses the survey area.