Ship strikes of large whales cause mortalities worldwide, but there is uncertainty regarding the frequency and species involved. We examined 130 records (from 1980–2006) of large whale strandings in Washington State. Nineteen strandings (seven species) had evidence of ship-strikes. Fin whales (Balaenoptera physalus) had the highest incidence of ante-mortem ship strike (five of seven, with the remaining two possibly post-mortem) and all but one occurring since 2002. Six grey whales (Eschrichtius robustus) suffered ‘possible ship strike’ injuries, likely the result of their large numbers in the area, rather than high levels of ship strikes. Only one possible ship-struck humpback whale was recorded, despite concentrations of humpbacks feeding within shipping lanes in this region. This study shows dramatic differences in occurrences of ship-struck large whales by species, which we believe results from a combination of species' vulnerability to ship strikes, and how likely a struck whale is to be caught up on the bow of a ship and brought to waters where it can be examined.

Killer whales in the Eastern Canadian Arctic (ECA) prey on narwhal, beluga, bowhead whales and seals, while further south in the north-west Atlantic (NWA), killer whales off the coast of Newfoundland and Labrador prey on both marine mammals and fish. Bulk and amino acid (AA) specific isotopic composition of dentinal collagen in teeth of 13 ECA/NWA killer whales were analysed to assess the degree, if any, of dietary specialization of killer whales across the region. Dentine was sampled from within annual growth layer groups (GLGs) to construct chronological profiles of stable nitrogen (δ15N) and carbon (δ13C) isotopic compositions for individual whales spanning 3–25 years. Interannual isotopic variation across GLGs was less than that among individuals, and median bulk δ15N values differed by up to 5‰ among individuals. Significant correlation between bulk δ15N values and baseline (source AA) δ15N values indicates much of the observed isotopic variation among individuals reflects foraging within isotopically distinct food webs, rather than diet differences. This interpretation is supported by consistent differences in bulk δ13C values between the two individuals with lowest source AA δ15N values and the remaining whales. After accounting for baseline isotopic variation, comparable δ15N values among individuals indicates similar trophic-level diet, although uncertainties in relative trophic 15N enrichment of individual AAs currently limits trophic position estimates for top consumers. Further research is required to clarify seasonal movement patterns and possible diet shifts of ECA/NWA killer whales to better define their role in marine ecosystems across the region.

The development of the persistent suture tag has permitted the study of long-term migrations of large decapods like the European edible crab (Cancer pagurus L.). A tagging study of the growth and migrations of C. pagurus was part of a research project undertaken to provide advice on the effective management of the English Channel crab fishery. During the years 1968–74 a total of 15296 suture-tagged crabs was released; the majority in the main fishery off south Devon and Cornwall, but releases were also made in the eastern half of the Channel. The early releases were mainly inshore, within 22 km (12 nautical miles), but as the fishery expanded offshore releases were made in mid-Channel.

Most of the recaptures occurred within two years of release, with the highest recapture rates being in the most intensively fished areas during the main fishing season. From the total of 2714 crabs recaptured, 2255 had reliable recapture information. In the inshore release areas 90 % of the males and 76 % of the females were recaptured within 18 km (10 nautical miles) of their release position. Offshore the corresponding proportions were considerably lower at 76 % and 59%, with 11 % of the males and 21 % of the females having moved > 90 km (49 nautical miles).

When males did move > 18 km they were mainly the larger males and their mean displacements were 14–31 km in several directions. The offshore releases of males in the middle and eastern Channel showed more extensive movements, which appeared to be directed, most of them being in a westerly direction, with mean displacements of 41–114 km. With only one exception, the female inshore releases had a mean direction of movement of between south and west, with mean displacements of 12–84 km. Overall, those females making the more extensive movements were larger than those caught in the vicinity of the release positions. The last inshore release at Portland Bill gave the first indication of extensive westerly movements from the eastern part of the English Channel.

Movements of females released on the offshore Devon and Cornwall grounds were mainly in a westwards direction, although several inshore movements and longer distance movements of up to 302 km towards the French coast were recorded. The recaptured females from the middle and eastern Channel releases showed greater mean displacements (110–158 km), all in a westerly direction. Only 10% of the mid-Channel recaptures were made within 18 km, with 73% being caught > 90 km from their release position. The highest mean velocity was 23 km/week, with an individual maximum of 183 km/week.

Most of the recaptures of male C. pagurus released inshore were made near the release position, and those movements which were observed would appear to be the result of nomadism. Offshore males seemed to be more mobile, but a nomadic existence for larger male C. pagurus seems more likely than migration. Female C. pagurus in the English Channel are more mobile than males. Large, mature, female crabs leave the eastern Channel and congregate in the autumn off south Devon. During the winter and spring there may be some nomadic movements. These migratory movements are reflected in the size composition and sex ratio. The migrations seem to be related to the breeding behaviour, ensuring a suitable sea-bed substrate for berried crabs and/or allowing distribution of the larval phase on the easterly residual currents in the English Channel.

The occurrence of an area of methane seepage off Chile is reported for the first time. Shell fragments of two species of bivalves of the genus Calyptogena and one species of Acharax were retrieved in dredge hauls from 651 to 934 m depth off Concepción (≈36°S). A large quantity of carbonate blocks was also collected, indicating anaerobic oxidation of methane in the sediment. The accompanying, non-chemosynthetic fauna from one of the hauls was diverse, containing some species new to science. Our preliminary data suggests an assemblage similar in structure to those reported elsewhere, albeit with an important endemic component.

A systematic review of the parasites, pathogens and commensals of the edible cockle (Cerastoderma edule) and of the lagoon cockle (Cerastoderma glaucum) has been completed. A total of 59 different conditions have been reported throughout the range of both of these hosts; of these 50 have been reported in edible cockles, and 28 in lagoon cockles. Cockles are hosts to viruses, bacteria, fungi (including Microsporidia), Apicomplexa, Amoeba, Ciliophora, Perkinsozoa, Haplosporidia, Cercozoa, Turbellaria, Digenea, Cestoda, Nematoda, Crustacea and Nemertea. A number of these have been reported sporadically although they may be associated with mortalities. In particular, mortalities have been associated predominately with digeneans and some protistan infections. In many cases pathology is marked in affected animals and parasites have been shown to reduce fecundity, alter burrowing behaviour and limit growth. This review provides information on the individual and population effects of these conditions as well as providing suggestions for future research. In particular, there has been a lack of taxonomic rigour applied to many studies and as a result there are a number of erroneous host records. There is a need to re-describe a number of parasite species and to determine the life cycle of those considered to be important mortality drivers.

Owenia may feed either by ciliary means or by swallowing sand and detritus. The gut consists of three main parts, a fore-gut or stomach which is secretory, a non-secretory mid-gut region which is absorptive, and a hind-gut which is non-secretory, non-absorptive and serves to elaborate and store the faecal pellets. The mid-gut contains coproporphyrin III and also phaeophorbide-6, to which the green colour is due. The green pigment in the epidermis is also phaeophorbide-ft, but phaeophorbide-a is apparently absent from the body.

Published behavioural, DNA sequence, and morphologic data on six populations of Mastigias, five from marine lakes and one from the lagoon, in Palau are summarized. Each marine lake population is distinguished from the lagoon population and from other lake populations by an unique suite of characteristics. Morphological differences among Mastigias populations in Palau are greater than those recorded between any previously described species of Mastigias, whereas molecular differences are far less (≤2.2% in COI and ITS1) than those found between medusae identified in the field as Mastigias papua (>6% in COI and ITS1). Thus, each marine lake population in Palau is described as a new subspecies of Mastigias cf. papua: remengesaui (in Uet era Ongael), nakamurai (in Goby Lake), etpisoni (in Ongeim'l Tketau), saliii (in Clear Lake), and remeliiki (in Uet era Ngermeuangel).

Allopetrolisthes spinifrons is an ectocommensal crab of the sea anemone Phymactis clematis. The population biology of A. spinifrons in north central Chile was examined between January and December 1996. During 1996, 74% of P. clematis in the rocky intertidal zone hosted at least one commensal crab. In most cases, one sea anemone was inhabited by a single adult crab, either male or female. A few sea anemones hosted two or more crabs, one usually being an adult and the others juveniles or small crabs that just had recruited to the host. The sex ratio of adult crabs was ∼1:1 during most months. Reproduction occurred with similar intensity throughout the year as indicated by the continuous presence of reproductive females. Similarly, recruitment of A. spinifrons occurred throughout the year with the exception of late winter when no megalopae and small juveniles were found on sea anemones. Fecundity of female crabs varied between 121 and 5661 eggs per female (6·9–19·2 mm carapace length) and was significantly higher during the austral winter (July) than during the summer (December). The fact that most sea anemones were inhabited by a single adult crab indicates that hosts may be monopolized by individual crabs. Resource requirements may prohibit adult crabs from sharing a host individual with another large crab, while adult tolerance towards juveniles may facilitate the maintenance of local populations.

A general description of the trophic inter-relationships and the food web within Bridgwater Bay, Somerset, England, is presented. This Bay is a lower estuarine site within the Bristol Channel. Particular attention is given to the use of the area by fish and larger crustaceans which are the dominant animal groups. Using data collected over a ten-year period of monthly sampling, the relative average biomass of all fish and larger crustaceans found within the Bay is calculated for each month of the year. These averages are used to produce food webs which also show species relative abundance for each calendar month.

It is shown that the trophic structure follows a seasonal cycle due to migration. The application of the concept of stability within such a dynamic system is discussed. The role of compartmentalization of the ecosystem into a number of loosely connected groups as an aid to overall stability is discussed. While there is no evidence that contemporaneous compartments exist, it is argued that inter-specific interactions are temporally limited because of the different periods of annual residence of the species. It is suggested that the stability and resilience to interference shown by these estuarine systems is enhanced by temporal partitions.

The maximum habitation depths of chambered cephalopods are dictated by the mechanical properties of the shell. All chambered cephalopods have a depth at which ambient pressure is sufficient to implode the gas-filled shell portions. Experiments on Sepia elegans D'Orbigny, S. officinalis Linne and S. orbignyana Férussac from the Mediterranean Sea show these three species to have differing depth limits and modes of shell implosion. Large S. officinalis implode between 150 and 200 m, whereas newly hatched and advanced embryonic specimens implode between 50 and 100 m. The larger S. officinalis are occasionally caught at depths greater than the implosion depth of the juvenile shell parts. They apparently avoid implosion of the early shell portions by refilling these first-formed chambers with cameral liquid later in life. Implosion in S. officinalis generally resulted in the crushing of all or most of the septa in a band extending from the embryonic region to the anterior part of the shell. Implosion was generally accompanied by fatal rupture of underlying tissue into the implosion zones. Implosion of S. orbignyana occurred between 550 and 600 m and was very different in form from that in S. officinalis, occurring mostly within the smooth zone of the last-formed several chambers, and rarely extending back into the siphuncular region (striae zone). Increasing depth caused episodic implosion of sequentially older chambers in the smooth zone. The shallower implosions were accompanied by little soft-tissue damage. Massive internal injury only occurred in the deepest implosions (700 m or greater). Implosion in S. elegans occurred betw en 400 and 600 m. Too few specimens were available to allow generalizations about morphology of implosion in this species.

The Plymouth Fauna List contains records of two genera of pteropods, Limacina and Clione. Of the first, Limacina retroversa (Flem.) is by far the better-known species, apparently occurring regularly at Plymouth in large numbers in townettings from outside, and sometimes inside, the Sound. It breeds at Plymouth from June to August, and Lebour (1932) has given a detailed account of its breeding and larval stages and has discussed its role in the plankton. The second species of Limacina at Plymouth is lesueuri (d'Orbigny), which has been observed from time to time since 1906, when it was very common. The last record in the Fauna is off the Breakwater in 1920. Of the gymnosomatous pteropods, Clione limacina Phipps is the only species regularly occurring. Lebour (1931) has described the life history of this form, and mentions February to August as its months of greatest abundance. Its breeding season is June to August. Another gymnosome, tentatively referred to as Clionina longicauda, is reported by Russell (1936), and from the specimen department at Plymouth Laboratory the writer obtained some preserved specimens, not easily identifiable, of a Pneumodermopsis taken locally; its species is perhaps ciliata, recorded by Massy (1917) from the Irish Coast.

The interstitial meiofauna was investigated on an exposed sand beach at Whitsand Bay, Cornwall. An intertidal transect of eight stations was sampled regularly over a period of 2 years from May 1968 to May 1970. Quantitative core samples were taken to a depth of 50 cm. Nematodes were the dominant group on the beach, forming about 50% of the meiofauna. Harpacticoid copepods were second in overall abundance. Hydrozoa, turbellaria, gastrotrichs and tardigrades were also present.

The ultra-structure of the epidermis of herring larvae is described. It is composed of two cell layers; the outer layer contains mitochondria, vesicles and a practically continuous layer having a dense 'fibrous' appearance. The cell border in contact with the sea water is thrown into an irregular arrangement of ridges and pits. The inner cell layer is usually thicker than the outer layer and lacks the continuous dense layer. No differences could be found in the structure or thickness of the epidermal cells of larvae reared in salinities of 5, 17·5, 35 and 50 ‰

Experiments on intact retinae from the eyes of the deep-sea fish Diretmus argenteus show that the region of the retina that receives light from above and possesses very long rods has different photosensitive pigments from the region that receives light from below. In both of these regions the retina has several banks of rods. The optical densities of the photosensitive pigments in the retina at the peaks of absorption are almost the same (about one) in these two regions. However, the region of the retina with very long rods also contains a stable yellow pigment that absorbs heavily in the blue and near ultra-violet (optical density about three at the wavelength 390 nm). If, as seems certain, this stable pigment is largely in the long rods it will filter the light reaching the other layers of rods and act, for this region, as yellow lenses do for whole retinae in other fish. The lens of Diretmus was shown to be transparent in the visible and near ultra-violet.

More than half of the species of British prosobranchs living intertidally have planktonic larvae. Settlement involves a positive response to certain factors which results in a speedy loss of structures fulfilling larval needs and the introduction of others associated with locomotion and feeding on the sea-bed (Fretter, 1972). Unless this response relates to the needs of the species, settlement could lead to mass mortality of larvae settling on unsuitable ground.

The biochemical constituents of mussels both infected and free from the copepod parasite Mytilicola intestinalis Steuer have been determined over a period of 2 years. All the constituents except moisture content (i.e. lipid, protein, carbohydrate and ash) were determined from dried mussel flesh, and all showed seasonal variation, the changes of which were correlated to the breeding cycle of the mussel.

Luminescence in decapod crustaceans may be of two kinds. Either a secretion is ejected into the surrounding water as a luminous cloud, or specific light organs, which may be internal or superficial, glow steadily (Balss, 1944). There may be more than 150 photophores in some species of decapod, and the number, position and development of these organs in Systellaspis debilis and species of Sergia have been described by Coutière (1906), Kemp (1910a), Terao (1917) and Gordon (1935). The production of luminous clouds has been observed in the Oplophoridae, Pandalidae and Thalassocarididae of the Caridea, and in the Penaeidae of the Penaeidea (Table 1). Observations of the luminescence of specific light organs or tissues are much less numerous. Luminescence has been observed among the Oplophoridae from the photophores of species of Systellaspis and Oplophorus and from the liver of Hymenodora. The hepatic organs of Parapandalus of the Pandalidae have been seen to luminesce, and among the Penaeidea both the hepatic organs of Pesta of Sergestes and the superficial organs of Sergia have been seen to emit light (for references see Table 1). Undoubted hepatic light organs also occur in Chlorotocoides and Thalassocaris of the Thalassocarididae, and superficial organs in Hymenopenaeus debilis of the Penaeidae. Additional organs of doubtful function which have been described as possible photophores occur on the chelae of the homolid crab Hypsophrys, in the branchial chamber of Sergestes, the pleopods of Parapandalus and the uropods of Acetes (Table 2). There are unconfirmed reports of luminescence in the eye of Pasiphaea etarda (Kiernik, 1908) and in Polycheles (Alcock, 1902) and Leptochela (Chace, 1940), neither of the latter two cases being ascribed to a particular organ, though ‘a greasy glandular patch’ near the oviduct was implicated in Polycheles.

The habitat, external appearance and habits of members of the Erycinidae, Montacutidae and Galeommatidae, three families included in the order Leptonacea, have been investigated and are described.

The ciliary currents of the gills, palps, visceral mass, foot and mantle are described in detail.

There is some reduction in the shell in this order. In Kellia, Lasaea, Montacuta and Mysella the shell is external and the adductor muscles are well developed. In Galeomma the shell and adductors are reduced, and in Devonia the shell is also partially covered by the mantle.

The foot is modified, and all members of this order progress on the flattened ventral surface of the foot which forms a creeping sole. The burrowing habit is lost.

The oil-spill removers BP 1002, Gamlen, Slipclean and Dasic have been tested for toxicity using the barnacle Elminius modestus Darwin. All four substances were more toxic than the laboratory detergent Teepol-L, and Kuwait crude oil. BP 1002 was the most toxic of the oil-spill removers, and Dasic the least, but all were poisonous at concentrations between 2 and 10 ppm.

The polychaete Nereis diversicolor F. O. Müller is one of the most characteristic elements of the brackish-water fauna of north-western Europe, and inhabits an extremely wide range of salinities. As a background for comparative physiological studies of chloride regulation in worms from different parts of the geographical range, the writer has attempted to describe the salinities and the variations in salinity endured by populations of N. diversicolor in eco-logically distinct and geographically well separated areas. Three principal environments have been studied: