This review provides insights into the distribution and impact of oestrogens and xeno-oestrogens in the aquatic environment and highlights some significant knowledge gaps in our understanding of endocrine disrupting chemicals. Key areas of uncertainty in the assessment of risk include the role of estuarine sediments in mediating the fate and bioavailability of environmental (xeno)oestrogens (notably their transfer to benthic organisms and estuarine food chains), together with evidence for endocrine disruption in invertebrate populations.

Emphasis is placed on using published information to interpret the behaviour and effects of a small number of ‘model compounds’ thought to contribute to oestrogenic effects in nature; namely, the natural steroid 17β-oestradiol (E2) and the synthetic hormone 17α-ethinyloestradiol (EE2), together with the alkylphenols octyl- and nonyl-phenol (OP, NP) as oestrogen mimics. Individual sections of the review are devoted to sources and concentrations of (xeno)oestrogens in waterways, sediment partitioning and persistence, bioaccumulation rates and routes, assays and biomarkers of oestrogenicity, and, finally, a synopsis of reproductive and ecological effects in aquatic species.

The concentrations of booster compounds were surveyed in the port of Osaka, Japan. The concentrations of Sea-Nine 211, Diuron and Irgarol 1051 in water samples from the port of Osaka were in the ranges <0·30–0·55 ng l−1, 13–350 ng l−1, 1·3–77 ng l−1, respectively. Pyrithiones were not detected in water samples. The levels of Diuron and Irgarol 1051 in the port of Osaka were high in the mooring area for small and medium-hull vessels with poor flushing.

Susceptibility of bacterial populations in estuarine water to antifouling biocides was studied. Sea-Nine 211, Diuron, Irgarol 1051 and Copper pyrithione dissolved in dimethyl sulfoxide (DMSO) were added to estuarine water and number of colony forming units (CFU) of bacteria in estuarine water was counted using R2A agar plate. The CFU was not decreased at the concentration less than 1·0 mg/l of Diuron, Irgarol 1051 and Copper pyrithione. However, CFU was decreased at 0·1 mg/l of Sea-Nine 211. Degradation of Sea-Nine 211, Diuron, Irgarol 1051 and Copper pyrithione by bacteria in estuarine water was studied using a die-away method. At an initial concentrations of 0·1 mg/l, observed half-lives of Sea-Nine 211 and Copper pyrithione were 10 and 20 days, respectively. In contrast, Diuron and Irgarol 1051 were degraded scarcely during 60 days of culture.

Photodegradation of these booster biocides by sunlight and UV light were studied. Under UV, all biocides were below detection limit after one day of irradiation. Under sunlight, Copper pyrithiones were also below detection limits after one day. Drastic decrease of Sea-Nine 211 concentration was observed after one day. Diuron and Irgarol 1051 scarcely decreased during 17 days of sunlight irradiation.

Regular sea temperature measurements have been made since 1975 at Gravelines (French coast of the Southern Bight of the North Sea) within the framework of a research programme aimed at monitoring the influence of the thermal discharge of a nuclear power plant. The sampling has yielded a 28-year time-series. Pluriannual natural fluctuations of temperature show cyclic patterns and long-term trends in good accordance with global climatic changes as revealed by the NAO (North Atlantic Oscillation) annual index.

The unicellular sporophyte phase of the filamentous green alga, Acrosiphonia (Codiolales), is endophytic in the bladed red alga, Mazzaella splendens in southern British Columbia, Canada. Since endophyte maturity coincides with decreased host abundance (winter storms dislodge Mazzaella blades), many endophytes lose their host before zoospore release has occurred. We investigated whether the endophytes can reach reproductive maturity within decaying host tissue (drift blades) or as free-living entities once their host has disappeared. We demonstrate that both occur. Suspension of M. splendens blades, colonized by the endophyte phase of Acrosiphonia, in seawater tanks in winter, resulted in the germination and growth of filamentous Acrosiphonia plants (gametophytes) in spring. Net primary productivity of 132·2 g dry wt/m2/mo was estimated by harvesting total Acrosiphonia biomass after a one-month growing season. An estimate of Acrosiphonia survivorship from zoospore to macroscopic adult gametophyte (0·01–0·89%), is in close approximation with kelp spore survivorship to microscopic gametophyte (0·005–0·1%), but is 102–105 times higher than kelp survivorship from spore to macroscopic adult sporophyte. Differential survivorship in the field and in experimental tanks and among different study sites can be explained by variable mortality factors for spores and germlings and Acrosiphonia's success in colonizing highly disturbed environments.

This paper reports the first study of breeding in the boreo-arctic barnacle Semibalanus balanoides in which latitudinal variation in timing of egg mass hardening has been examined simultaneously over the geographical scale involved, thereby excluding temporal confounding of the data. The timing of autumn egg mass hardening on the middle shore was established in 2002 and 2003 at ten stations ranging latitudinally from Trondheim (63°24′N) to Plymouth (50°18′N). To assess variation at local scale (<10 km), breeding was studied on three shores at each of two Irish locations (Cork and Galway). At Oban (Scotland) and Cork, the effect of shore height on timing of breeding was investigated. A strong influence of latitude and day length on timing of breeding was found in both 2002 and 2003. In both years, barnacles bred much earlier (when day length was longer) at high rather than low latitudes. No significant effect of environmental temperature or insolation on timing of breeding was detected. Shores no more than 10 km apart showed minimal difference in middle shore breeding date (<4 days). However, upper shore barnacles bred significantly earlier (by 7–13 days) than middle shore animals. The data indicate that breeding is controlled by period of daily darkness, with high shore animals encountering longer effective ‘nights’ because of the opercular closure response to emersion (which will reduce light penetration to tissues). Predictions concerning the effects of global changes in climate and cloud cover on breeding and population distribution are made. It is suggested that increased cloud cover in the northern hemisphere is likely to induce earlier breeding, and possibly shift the present southern limit of Semibalanus southwards.

A new species of the planktonic copepod Tortanus (Atortus) (Calanoida: Tortanidae), T. (A.) magnonyx is described from the Seychelles, Mauritius and Madagascar. This is the sixth species of the Indian Ocean recticauda species group, of the Indo-West Pacific recticauda species complex, that has been described from the western Indian Ocean. The inshore areas where these copepods are found have been poorly surveyed, so the number of species found implies a high diversity.

This investigation constitutes the first study of the serotoninergic nervous system in calanoid copepods (crustaceans). Serotonin (5-HT), a neurotransmitter which plays a part in many biological processes, has been detected by immunofluorescence in the brain, the circumoesophageal collar and the ventral nerve cord of the marine species Centropages typicus.

A molecular assay was designed to distinguish the common sea louse Caligus elongatus from its sympatric relatives. The method identifies the parasites at all developmental stages. Fragments of the mitochondrial Cytochrome C Oxidase 1 (COI) gene from identified adult caligids were amplified by polymerase chain reaction (PCR) and sequenced. Analysis of sequence data from unknown samples permitted identification by clustering of the samples with their appropriate genetic relative. Nucleotide sequences obtained were used for preliminary investigations of the population genetic structure of Caliguselongatus. Aligned sequences from the COI gene from this speciesindicate that our C. elongatus material divides into two distinct clades, possibly revealing two closely related species. The two genotypes do not appear to be associated with sample site, parasite gender, sample time or host species. Parasites from both groups were found on Atlantic salmon (Salmosalar), sea trout (Salmotrutta), pollack (Pollachiuspollachius), saithe (Pollachiusvirens), and Atlantic herring (Clupeaharengus).

Six specimens of an unknown Argulus species were found on a cod caught off the coast of Finnmark in northern Norway. All six were found to be sixth stage male larvae, ∼2·6 mm long and 1·6 mm wide. Argulus has not previously been recorded from cod and this is also the first record of a marine Argulus from Norwegian waters. The Argulus sp. from cod can be easily distinguished from other marine species found in northern European waters, and also from Norwegian freshwater species of Argulus. It is believed that it represents a new species, but a complete species description must await the finding of adult stages.

Mobile lice levels of two species of sea lice, Lepeophtheirus salmonis and Caligus elongatus, were examined on two samples of Atlantic salmon from the west coast of Ireland. The samples examined were taken two weeks apart from salmon caught by drift net in June 2003 at two different locations off the west coast of Ireland, one in the north-west and one in the west. Both samples of salmon caught were comparable in terms of numbers of total lice counted. No significant differences in male, female and ovigerous L. salmonis levels between the two samples were recorded, however, a significant difference was recorded between juvenile L. salmonis levels. Morphometric comparisons of male and ovigerous L. salmonis examined for each of the two salmon samples examined revealed some differences. There was a significant difference in male L. salmonis in terms of cephalothorax length between the samples. In the females significant differences were found between cephalothorax length, overall total length and egg length. Significant positive correlations within samples were also observed, between total female body length and both total egg number and egg string length in one of the samples examined.

Caprella wirtzi sp. nov. from the Cape Verde Islands is described. It is close to C. liparotensis a species recorded from Portugal and along the Mediterranean coasts to the Black Sea, but distinguished from C. liparotensis by the morphology of antenna 2, gnathopod 2 and peraeonites 3, 6 and 7. Variation from C. liparotensis is also discussed.

Individuals of Lysmata wurdemanni first mature in a male phase (MP) and then change to the external phenotype of females (female-phase=FP). The FPs retain the male gonadal system and function both as male and female (simultaneous hermaphrodites). The cost of maleness to FPs on fecundity was estimated with an experiment in which the social environment (FP opportunity to function as a male) was varied. The effect of maleness on brood size (number of embryos brood−1) and frequency of spawning (interspawn interval in days) was measured in FPs maintained in different social environments (treatments) over two complete spawning cycles. In treatment 1 (isolated FP) and 2 (1 FP, 1 MP), FPs could only function as females. In treatments 3 (2 FPs) and 4 (5 FPs, 5 MPs), FPs could breed both as male and female.

Baseline brood size was described for FPs with a regression equation of brood size on FP body size (carapace length). Brood size is positively and isometrically related to FP size. Brood sizes, adjusted for FP body size using the baseline regression equation, were compared among treatments 2–4 (isolated FPs in treatment 1 did not produce fertile broods). Brood sizes were significantly greater in FPs in treatment 2 (only female breeding) than in treatments 3 and 4 (both male and female sexual function possible). However, spawning was less frequent (longer interspawn intervals) in treatments 1 and 2 than in treatments 3 and 4. Total fecundity over a four-month breeding period was estimated with a model using mean treatment brood sizes and interspawn intervals. Estimates of total fecundity in FPs functioning both as male and female were much lower, in spite of somewhat more frequent spawning, than those in which male function was not allowed. The ‘price’ (cost) of maleness on fecundity appears to be compensated by the high selective advantage of male mating ability in the simultaneous hermaphrodite FPs of Lysmata species.

The influence of several environmental factors on the abundance and spatial–temporal distribution of the shrimp Artemesia longinaris were investigated from January 1998 to December 1999 in the Ubatuba region of São Paulo State, Brazil. Collections were performed monthly in the bays of Ubatumirim (UBM), Ubatuba (UBA) and Mar Virado (MV). Six sampling transects were established in each bay, four were parallel to the shore line, and two were next to the rocky shores. A commercial shrimp fishing boat equipped with two ‘double-rig’ nets was used. A total of 11,503 individuals was collected, including 1633 from UBM, 6344 from UBA and 3526 from MV. The majority of the captured specimens came from the deeper areas (15 to 20 m) with high salinity (34 to 36 ppt). The highest abundance of A. longinaris in Ubatuba bay was recorded in areas where fine and very fine sand comprised more than 70% of the sediment. Moreover, the abundance of A. longinaris followed a seasonal trend, being higher during the summer, when intrusions of cold South Atlantic Coastal Waters (SACW) are frequent. Thus, type of sediment, temperature and salinity are determinant factors in the distribution of A. longinaris in the studied region.

The hypothesis that vital functions of one of the most successful macroinvertebrates of sandy beaches of Chile, the mole crab Emerita analoga are negatively affected by the environmental conditions of reflective beaches was tested. Twelve exposed sandy beaches distributed along 200 km of coast of central Chile, and selected to cover a wide morphodynamic spectrum were sampled every two months from April 1997 to November 1998. Significant phenotypic differences among local populations of the sand crab were detected. Important life history traits of the sand crab, linked to growth pattern, reproductive biology and burrowing capacity, were negatively affected by the environmental conditions of reflective beaches. The present results reinforce the view that environmental variations associated with beach morphodynamics, play a critical role in the life history patterns of sandy beach organisms.

The population biology and reproduction of the hermit crab Clibanarius longitarsus were studied with emphasis on size structure, sex ratio, breeding season and fecundity. Specimens were sampled monthly over a period of one year (January–December 2003) at Costa do Sol mangrove, Maputo Bay, southern Mozambique. A total of 597 individuals was obtained of which 202 were males, 192 non-ovigerous females and 203 ovigerous females. Annual size–frequency distributions were polymodal for males and bimodal for non-ovigerous and ovigerous females, respectively. Sexual dimorphism was recorded by the larger average size attained by males in relation to females. Sex ratio was female-biased during most months of the study. Clibanarius longitarsus showed a higher reproductive activity with two major peaks (March and October). Juvenile recruitment was continuous throughout the study period. Clutch size was positively associated with female size. The high number of ovigerous females as obtained in the present population may evidence a higher reproductive activity displayed by C. longitarsus at Costa do Sol mangrove.

The hermit crab Pagurus brevidactylus (Crustacea: Anomura: Paguridea) from the infralittoral area of Anchieta Island, Ubatuba, was characterized by population structure (size, sex ratio, reproduction and recruitment) and growth. Animals were collected monthly during 1999 by SCUBA diving. A total of 1525 individuals was collected (633 males and 892 females), 695 of them were ovigerous females. Overall sex ratio was 0·7:1 in favour of females. The crabs showed a unimodal distribution with males significantly larger than females. Ovigerous females were collected during all months and in high percentages from 1·0 mm of shield length, demonstrating intense and continuous reproduction. The longevity was approximately 24 months for males and 18 for females, which showed larger growth rate and reached sexual maturity earlier (two months) than males. The low number of males in this population may be due to the longer life span. Moreover, the sexual dimorphism favours males during the intra- and interspecific fights by shell, food, reproduction and territory. Females demonstrated a short life cycle and intense reproduction.

Methods for assessing the occurrence and recency of mating are important for the management and conservation of exploited brachyuran crabs. Using multiparous females of the snow crab Chionoecetes opilio, we evaluated by experiment the efficacy of three indicators of recent mating: a white deposit in the spermathecae, extended mate-guarding, and fresh grasping marks on the female pereiopods. This was done by contrasting sperm counts between the left and the right spermatheca of females that were exposed to males with the right gonopod ablated, at treatment sex ratios of 20[female]:3[male ] or 50[female]:3[male ]. We expected that sperm reserves would be balanced between the two spermathecae of non-mated females and larger in the right than in the left spermatheca of mated females. Although no mating indicator was infallible, the presence of a white deposit was the most accurate because it maximized the median difference of sperm counts between the two spermathecae for the group of presumably mated females and minimized it for the group of presumably non-mated females. The use of grasping marks overestimated the mating frequency and resulted in the misclassification of a large proportion of females. Extended mate-guarding was a slightly better mating indicator than grasping marks, but it is not practical for field studies. Classification errors associated with each indicator can be explained mostly by female and male behaviours and may vary in magnitude with sociosexual context.

Two new species of Munida (M. gordoni and M. grieveae) and one new species of Agononida (A. nielbrucei) are described from volcanic seamounts off northern New Zealand (RV ‘Tangaroa’, National Institute of Water and Atmospheric Research [NIWA], New Zealand). Description of new species and preliminary examination of NIWA collections reveal unusually high endemism of volcanic seamount populations of Galatheidae.

Laboratory breeding of the dog-whelk, Nucella lapillus, has established that the male-sterilizing Dumpton Syndrome (DS)—underdevelopment, or non-development (aphally), of the penis, incomplete formation (non-closure) of the vas deferens, resulting in a split prostate—can be readily observed in male F1 progeny. Cultivated under high ambient concentrations of the antifouling agent tributyltin (TBT), DS-carrying females can be recognized by their lesser degree of masculinization (imposex): sterilization is thereby avoided. When Dumpton females are crossed, under high ambient TBT, with individuals from a non-DS-affected population (Bude, North Cornwall) DS is absent from both sexes. Crosses of these F1 progeny result in F2 progeny exhibiting the classic DS symptoms in both sexes. A Mendelian mechanism for DS inheritance is suggested by the data.

Shell growth of the whelk Nassarius (=Hinia) reticulatus was studied in the Ria de Aveiro (north-west Portugal) between 1995 and 1998. Temporal analysis of shell height frequency distributions demonstrated that growth occurs during the first five years of life, whelks attaining a size of 6·7–7·8 mm in the 1st year, 12·1–14·5 mm in the 2nd year, 18–19·5 mm in the 3rd year, 22·7–23·6 mm in the 4th year and by the 5th year males have achieved an average size of ∼25 mm whilst females have reached ∼27 mm. Age estimates from internal microscopic annual growth lines present in the shell lip suggest that large whelks may achieve a longevity of at least 11 years. External annual rings become less discernible as the whelks increase in size and estimates of their age based solely on ring counts can underestimate their age. In males sexual maturation is reached between the 3rd and 4th years whilst in females it is attained between the 4th and 5th years. Imposex was visible in ∼2 year old females and attained maximum development by the 5th year.