Many species of sea urchins cover their bodies with a variety of materials. One hypothesis for this behaviour is that the urchins are reducing their exposure to UV radiation. The effect of UV radiation on the covering behaviour of twelve sea urchins, Lytechinus variegatus, was recorded and the shells used as covering materials were quantified. During UV exposure, urchins used significantly greater numbers, areas and masses of shells than did urchins during non-UV exposure. Results suggest that not only were L. variegatus covering in response to UV exposure, but they were also making distinct choices regarding preferred covering items. Unlike in previous studies, the urchins did not simply choose familiar objects or even the lightest objects; rather, when exposed to UV radiation they selected intermediate-sized objects, perhaps demonstrating a trade-off between the energetic costs of carrying objects and the physiological costs of exposure to UV radiation. While there appear to be many reasons for why urchins cover, these results indicate that urchin covering is non-random and has important functional significance.

Sperm whale (Physeter macrocephalus) teeth were used to investigate whether variation in the chronological profiles of carbon and nitrogen stable isotope ratios along dentine growth layers could reflect differences in ontogenetic movements and/or dietary shifts in animals from different regions and sexes, as well as to show the differences in the isotopic environments experienced by these animals. Absolute isotopic ratios ranged from -14.1 to -11.0‰ for carbon and 10.8 to 18.1‰ for nitrogen, with the whale from the Indian Ocean, the two from the Mediterranean Sea and the female from the Azores presenting the most different median isotopic ratios. The Icelandic and the Indian Ocean males showed the expected decrease in δ13C around the age of ten, denoting male segregation from natal groups. For the latter, this was larger by almost twofold compared to other teeth, probably due to the much stronger latitudinal gradient in planktonic δ13C in the southern hemisphere. The Mediterranean Sea whales exhibited the lowest median δ15N values, probably reflecting the oligotrophy of this sea, while the male showed a marked change in isotopes around the age of 20 that could indicate a move to the eastern basin or a temporal change in basal isotopic signatures. The Atlantic females did not show a marked change in δ13C as expected since they stay in low latitudes throughout their lives. Stable isotope profiles in whale teeth can be used to investigate differences in the timings of ontogenetic movements and dietary history between individuals and sexes, and the biogeochemistry of different regions inhabited, and have the potential to allow inferences to be made about population substructure.

Marine sponges are abundant and diverse components of coral reefs and commonly harbour photosynthetic symbionts in these environments. The most prevalent symbiont is the cyanobacterium, Synechococcus spongiarum, isolated from taxonomically diverse hosts from geographically distant regions. We combined analyses of chlorophyll-a (chl-a) concentrations with line-intercept transect surveys to assess the abundance and diversity of reef sponges hosting photosymbionts on Caribbean coral reefs in the Bocas del Toro Archipelago, Panamá. To identify symbionts, we designed PCR primers that specifically amplify a fragment of the 16S ribosomal RNA gene from S. spongiarum and used these primers to screen potential host sponges for the presence of this symbiont. Chlorophyll-a data divided the sponge community into two disparate groups, species with high (>125 μg/g, N=20) and low (<50 μg/g, N=38) chl-a concentrations. Only two species exhibited intermediate (50–125 μg/g) chl-a concentrations; these species represented hosts with reduced symbiont populations, including bleached Xestospongia muta and the mangrove form of Chondrilla nucula (C. nucula f. hermatypica). Sponges with high and intermediate chl-a concentrations accounted for over one-third of the species diversity and abundance of sponges in these communities. Most (85%) of these sponges harboured S. spongiarum. Molecular phylogenies reveal that S. spongiarum represents a sponge-specific Synechococcus lineage, distinct from free-living cyanobacteria. The prevalence of sponge–photosymbiont associations and dominance of symbiont communities by S. spongiarum suggest a major role of this cyanobacterium in sponge ecology and primary productivity on coral reefs.

Fatty acid profiles were used to investigate aspects of bottlenose dolphin populations around the Azores archipelago. Biopsy samples were obtained from 70 dolphins during the period 2002–2004. No statistically significant differences in profiles were found between different island groups, between sexes or between year of sampling. Thus no evidence was seen for island group fidelity, in contrast to bottlenose dolphins found around similar island groups such as the Hawaiian archipelago or the Bahamas. The findings are consistent with concurrent genetic and photo-identification studies on dolphins in the Azores.

The present work records for the first time the association between ophiuroids and the octocoral Carijoa riisei. Carijoa riisei is a colonial octocoral very abundant in the littoral of Pernambuco (Brazil), with growth by creeping stolons with an arborescent structure creating an optimal environment for epibionts. The objectives of the work were to identify the species of Ophiuroidea associated with C. riisei, and to verify the existence of seasonality through the density, abundance and frequency of sampled taxa. Due to the known relationship between the ophiuroids and sponges related in the literature, the sponges founded associated with C. riisei were recorded. Seasonal samples of the beaches of Porto de Galinhas and Guadalupe were realized. In Guadalupe, 39 and 21 ophiuroids (dry and rainy seasons respectively) belonging to the families Ophiactidae (Ophiactis savignyi, Ophiactis lymani) and Ophiotrichidae (Ophiotrhix angulata) were identified. Ophiactis savignyi stood out in all the analysed stations (48.72% in dry season and 52.38% in rainy season). The average density of the ophiuroids was 10.74 ind/100 g of C. riisei, varying from 12.56 ind/100 g in the dry season to 8.92 ind/100 g, in the rainy season. Amongst the species of ophiuroids recorded in the samples, O. savignyi showed 80% and 100% frequency of occurrence in the dry and the rainy seasons, respectively, and O. lymani showed 80% during the dry season. The presence of O. lymani in Guadalupe constitutes the first record in Pernambuco state. Taking into account that all the ophiuroids collected in Guadalupe were considered juveniles (1–3 mm of disc diameter), the microhabitat created by C. riisei may be utilized as a recruitment place for some ophiuroids. No ophiuroids were found at Porto de Galinhas beach, just as for sponges. On the other hand, the ophiuroids were always found with sponges in Guadalupe beach. For this reason, the ecological relation of the ophiuroids with C. riisei could be observed as an occasional relation, in the way that the octocoral supplies a support structure to the growth of the many sponges that have given a favourable habitat to shelter ophiuroids.

This study reports on the transfer of heterotrophic bacteria from parental tissue to oocytes in the Mediterranean bacteriosponge Corticium candelabrum (Homosclerophorida) and the description of the successive locations of the microsymbionts during embryo development through transmission and scanning electron microscopy. Eight different types of symbiotic bacteria are described morphologically. These eight bacteria morphotypes are found in both adult individuals and larvae. Symbiotic bacteria are transferred to oocytes, but not to spermatocytes. Bacteria are first located at the oocyte periphery below a thick collagen layer and then they migrate to the oocyte cytoplasm, forming spherical clusters. After cleavage, the bacteria can be found in the free space between blastomeres but mainly accumulate at the embryo periphery below the follicular cells that surround the embryo. Once the blastocoel is formed, the symbiotic bacteria move to this central cavity where they actively divide by bipartition, increasing their number considerably. Many examples of phagocytosed bacteria in the proximal zone of the larval cells are observed at this stage. Consequently, bacteria may represent a complementary source of energy for free larvae and settlers before they are able to capture food from the surrounding water.

We describe the diet of bottlenose dolphins Tursiops truncatus in Galician waters, north-western Spain, based on 82 non-empty stomachs recovered and analysed from stranded animals between 1990 and 2005, quantifying interannual and seasonal variation in the diet, as well as dietary variation related to sex and size. The most important prey species (in terms of numerical importance and biomass) were blue whiting (Micromesistius poutassou) and hake (Merluccius merluccius), both of high commercial importance in Galician waters. Most blue whiting eaten by dolphins were mature fish but the estimated total consumption was relatively low (around 10%) compared to Spanish fishery landings of this species. In contrast, most hake eaten by dolphins were probably immature but the estimated total consumption is more than 20% of current annual fishery landings. The diet of by-caught animals, which made up around one third of the sample, was very similar to that in the overall sample. Although bottlenose dolphins are often seen close inshore, evidence from the diet suggests that they feed at the shelf edge. Evidence was found of ontogenetic dietary shifts and differences between diets of male and female dolphins. There were also clear changes in average diet over the 16-year study period, although there was no evidence that they were in response to changes in fish abundance. The amount of hake in the diet remained stable against a background of falling local abundance while the amount of blue whiting declined despite an increase in spawning stock size.

A total of 13 species of carcharhiniform sharks (excluding the families Carcharhinidae and Sphyrnidae) belonging to four families was recorded in fish landing site surveys in eastern Indonesia. Of these, the Triakidae were most abundant in the landings with Hemitriakis sp. 1 and Mustelus cf. manazo both contributing 1.8% to the total number of all sharks recorded. A number of the species, i.e. Atelomycterus baliensis, Halaelurus sp. 1, Hemitriakis sp. 1, Mustelus cf. manazo and Mustelus widodoi, were first recognized during these landing site surveys. A size at maturity for males of the two most abundant scyliorhinids, Atelomycterus marmoratus and Halaelurus sp. 1, could not be accurately determined, but they attained maturity at 419–506 and 360–404 mm TL, respectively. The latter species displays multiple oviparity with the uteri of pregnant females possessing six or 12 egg cases, each containing early to mid-term embryos. The length at first maturity (L50) of males of Hemitriakis sp. 1 and M. cf. manazo was 900 and 859 mm TL, respectively, and the length at birth was approximately 280 mm TL in both species. The mode of reproduction in both of these species was viviparous, with histotrophy. The most abundant hemigaleid species, H. microstoma, was found to mature at a far larger size than the only other congeneric species H. australiensis, i.e. 750–780 vs 600–650 mm TL, respectively. The data presented in this paper are the first such biological data reported on six of these shark species and are thus vital for fisheries managers and conservation assessors, especially given the extent of the shark and ray fisheries in Indonesia.

Stomach contents were analysed from three species of beaked whales which mass-stranded shortly after a naval exercise conducted in the Canary Islands in September 2002. Animals from such mass strandings often contain freshly ingested food in their stomachs and can provide a more reliable guide to feeding habits than other strandings. Food remains recovered from seven Cuvier's beaked whales (Ziphius cavirostris) consisted mainly of oceanic cephalopods, the most numerous being Taonius pavo, Histioteuthis sp., Mastigoteuthis schmidti and Octopoteuthis sicula. Many of the cephalopod species found in the diet appear to undertake daily vertical migrations, being found in shallower waters during the night and moving to deeper waters during the day. Single specimens of Blainville's beaked whale (Mesoplodon densirostris) and Gervais' beaked whale (Mesoplodon europaeus) had eaten both fish and cephalopod prey. The most numerous prey remains belonged to gadid fish and viperfish (Chauliodus sp.) respectively. These results are consistent with the limited published data on diet in these species, with Mesoplodon species having a relatively higher proportion of fish in the diet whereas Ziphius specialises on cephalopods.

The chain catshark (Scyliorhinus retifer) is a member of one of the most well studied groups of elasmobranchs (Order: Carcharhiniformes), yet its feeding strategy is unknown due to the inaccessible deep water environment in which it lives (greater than 200 m). To investigate the feeding biology of captive S. retifer, high-speed videography was used to document the kinematic events during capture of two differently sized fish pieces, ‘large’ (scaled to the mouth width), and ‘small’ (scaled to one-half the mouth width). Despite a significant delay in the timing of select kinematic variables for large food captures, a multivariate analysis of the feeding behaviour indicated that overall, food capture kinematics and strike behaviour in S. retifer were not statistically different between large and small items (MANOVA, Wilks' Lambda P =0.598, df=4,24). Food capture in S. retifer was suction-dominant, with items being drawn into the mouth about twice the distance that the predator moved. While suction-dominant food capture appears to be an advantage to benthic predators, it contrasts sharply with the phylogenetic position of S. retifer among several ram-feeding carcharinoid sharks including Cephaloscyllium ventriosum, a member of the same family (Scyliorhinidae). Thus, feeding mode in carcharinoid sharks seems to reflect their ecology and does not appear to have been phylogenetically constrained.

Recent molecular detection of vast microbial communities exclusively associated with sponges has made evident the need for a better understanding of the mechanisms by which these symbiotic microbes are handled and transferred from one sponge generation to another. This transmission electron microscopy (TEM) study investigated the occurrence of symbiotic bacteria in free-swimming larvae of two viviparous species (Haliclona caerulea and Corticium candelabrum) and spawned gametes of two oviparous species (Chondrilla nucula and Petrosia ficiformis). Complex microbial communities were found in these sponges, which in two cases included bacteria characterized by an intra-cytoplasmic membrane (ICM). When ICM-bearing and ICM-lacking bacteria co-existed, they were transferred following identical pathways. Nevertheless, the mechanism for microbial transference varied substantially between species. In C. nucula, a combination of intercellular symbiotic ICM-bearing and ICM-lacking bacteria, along with cyanobacteria and yeasts, were collected from the mesohyl by amoeboid nurse cells, then transported and transferred to the oocytes. In the case of Corticium candelabrum, intercellular bacteria did not enter the gametes, but spread into the division furrows of early embryos and proliferated in the central cavity of the free-swimming larva. Surprisingly, symbiotic bacteria were not vertically transmitted by P. ficiformis gametes or embryos, but apparently acquired from the environment by the juveniles of each new generation. This study failed to unravel the mechanism by which the intercellular endosymbiotic bacterium found in the central mesohyl of the H. caerulea larva got there. Nevertheless, the ultrastructure of this bacterial rod, which was characterized by a star-shaped cross section with nine radial protrusions, an ICM-bound riboplasm, and a putative membrane-bound acidocalcisome, suggested that it may represent a novel organization grade within the prokaryotes. It combines traits occurring in members of Poribacteria, Planctomycetes and Verrucomicrobia, emerging as one of the most complex prokaryotic architectures known to date.

Reports of disease in sponges are increasing, but the paucity of data on disease prevalence over time makes it uncertain how much this trend reflects increased attention to sponges rather than increased sponge disease. Population and community influences on disease dynamics, and the consequences of disease at these levels, are also little known. Five censuses, over 14 y, of a small plot on a shallow coral reef at San Blas, Panama, provide data for the three most abundant species on population dynamics (number of individuals and total volume) and disease prevalence (number of individuals with active lesions). Although data for the three species, combined in broad categories (i.e. high vs low), support a general conclusion that disease prevalence was greater from 1994–1998 than from 1984–1988, the data do not demonstrate a steady increase over time, and disease prevalence for two of the species decreased in each of the final two censuses from a high in 1994. Fluctuations in population density (total volume) and disease prevalence were nearly synchronous within individual species, but asynchronous among the three species, suggesting that population density, measured as total sponge volume per unit area, may influence disease dynamics in these sponges.

Along the central coast of Rio de Janeiro State (22°25′S–23°00′S), south-eastern Brazil, the marine tucuxi dolphin (Sotalia guianensis) feeds on neritic prey that are distributed through the water column and are abundant all year round. The most frequently found species were the teleost fish Trichiurus lepturus, Cynoscion guatucupa, Isopisthus parvipinnis and Porichthys porossisimus. Fish species were more important than cephalopod species in the diet of the marine tucuxi. Back calculations of prey sizes indicated that they feed mainly on young specimens. The present study provided additional information on the feeding habits of the marine tucuxi dolphin.

The present study considered the influence of the tide on shallow water fish assemblages within the Wakatobi Marine National Park, Indonesia. Timed underwater visual observations were made across a gradient of intertidal to subtidal habitats from near-shore to reef crest at different tidal heights. Transient fish were found to dominate shallow water fish assemblages and the assemblage composition varied with tidal state. Fish assemblages were more diverse and abundant at higher tides in both coral and sea grass habitats, however, this was more pronounced within sea grass habitats. A tidal reduction from ≈2.0m to ≈0.8m (above chart datum) corresponded to a 30% reduction in fish abundance, while species richness also significantly decreased from 13.5 to 10.8 species per standardized timed observation. Fifty fish groups were reported from sea grass habitats with the most abundant being from the Engraulidae family and Lethrinus harak, which form important local subsistence fisheries. This research confirms the importance of tidal changes in structuring the fish fauna of Indonesian sea grass habitats and underlines the connectivity that exists between these habitats and nearby coral reefs.

Beds of the seagrass Zostera capricorni are an integral part of the estuarine landscape along the east coast of Australia, forming an important habitat for juvenile fish. Seagrass beds can vary in their size, shape and patchiness of seagrass cover as well as their distance from the estuary mouth. We tested for a correlation between these features and small fish assemblages in seagrass. Fifteen beds were selected from three size-categories (small, 980 to 2300 m2; medium, 3375 to 4090 m2; and large, 5335 to 6630 m2). We found that the size of beds, the patchiness of seagrass cover and location within the estuary (distance from estuary mouth) were all related to differences in fish assemblages. There were greater densities of fish species in small (10.3 ±0.79 species .net-1) compared to medium (7.6 ±0.6) and large (8.2 ±0.5) beds. This occurred regardless of bed placement within the estuary, its patchiness or time of sampling (day and night). The fish assemblages within seagrass beds also changed as bed distance to estuary mouth increased. Six species had greater densities in beds closer to the estuary mouth, while only two species were in greater densities far from the mouth. Fish assemblages were different between beds with patchy and continuous cover, although total densities of all fish species combined were similar. There were greater densities of four species in continuous beds compared to two species that were greater in patchy beds. Overall, an important finding was that even small patchy seagrass beds contain greater densities of small fish species than larger beds with continuous seagrass cover.

Deep water cladorhizids are now generally thought to be carnivorous. While the methods of prey capture have been established for species of Asbestopluma, and perhaps Chondrocladia, information is sparse for species of Cladorhiza. The external morphology of the deep-sea Alaskan species, Cladorhiza corona, was examined immediately after collection, and then again later using scanning electron microscopy (SEM). All sponges examined had captured, and in most cases, fully encased, prey items which for the most part consisted of planktonic copepods. The hypothesis of this paper is that the primary process of prey capture is by means of a sticky substance and that prey stick to the sponge on contact. The abundant cladorhizid anisochelae do not seem to be arranged in a manner such that they can be used for prey capture as has been seen in Asbestopluma. Digestion of the prey occurs in a temporary cavity created by migrating sponge cells. Within this cavity lipid from the copepod is liberated, then absorbed and transported to the central part of the sponge. It is not known how much of the remaining tissue of the copepod is digested. Copepods have very high lipid content so their capture would provide the sponge with abundant energy from each prey item. The sponges seem to have their highest density in areas where bottom flow and migrating copepod numbers are both high.

The north-east Atlantic grey seal, Halichoerus grypus, is widely distributed along the European coastline from northern Russia to France, with the core population centred around Scotland. To date, very little is known of the diet of the species at the southern margin of the species range. However, because grey seal numbers have been increasing over the last few decades in France, the issue of their potential interactions with coastal fisheries is frequently raised. The diet of grey seal in the Molène Archipelago was investigated by combining scat, stomach content and fatty acid analyses, since all three approaches have complementary potentials to reveal feeding habits of a predator. A total of 145 scats mostly of moulting adult males, 14 stomach contents of yearlings and 14 blubber samples from animals of all ages were analysed following standard methodologies. Scats revealed a diet mainly constituted of 50.6% by mass (M) of wrasse, Labridae (mostly Labrus bergylta), 20.7%M conger eel, Conger conger, and 11.9%M sea bass, Dicentrarchus labrax. Stomach contents were made up of 52.3%M cuttlefish, Sepia officinalis, 9.5%M sole, Solea solea, and 9.4 %M conger eel. All these prey are different from the diet observed in core areas. Fatty acid analysis from the blubber confirmed that the diet differed between the Molène Archipelago and one of the Scottish breeding sites. It also showed that most of the inter-individual variability was explained by variation in seal body masses, which could be linked to behavioural ontogeny of foraging strategies. Most of the prey species identified in the food of the grey seal in Brittany are also targeted by professional and/or recreational fisheries in the area; additionally, several prey size-ranges also partly overlap with marketed size-ranges for several species.

Parablennius ruber, the red or Portuguese blenny, is reported from the British Isles. This species has recently been revalidated as separate from P. gattorugine and this, together with confusion about the field identification characteristics which distinguish the two species, is likely to have resulted in it being under-recorded. Parablennius ruber was found to be fairly widespread on the exposed west coasts of the Republic of Ireland and Scotland (22 records), with additional records from the Isles of Scilly (3 records) and Northern Ireland (1 record). One record was made of egg guarding. Most records were from exposed areas of bedrock and boulders, between 15 and 30 m in depth. Field identification characteristics which distinguish between P. ruber and P. gattorugine are given. Given that its original description was from Ushant in 1836, it is unlikely that P. ruber is a fairly recent addition to the British fauna as a result of increased water temperatures. However, given its habitat, the fairly recent advent of sampling by SCUBA diving is likely to have increased the potential for sightings. The growth of SCUBA diving and the increase in the use of underwater digital photography are likely to result in a better knowledge of its distribution.

Chondrilla nucula is a morphologically simple species defined by the presence of spherasters in its skeleton. For a long time C. nucula was considered a cosmopolitan species, however, in 1999, a molecular study demonstrated the existence of a species complex with at least four cryptic species, besides C. nucula. At that time, those four new species were not formally described because the morphological differences observed did not reflect species differences and were attributed to plasticity. Since then, researchers working on Chondrilla species suggested that the skeletal organization, the distribution of spherulous cells and the type of surface should be used to differentiate species. Individuals of Chondrilla aff. nucula from one population in Arraial do Cabo, Rio de Janeiro State, Brazil, were collected monthly and analysed in order to test the validity of those three characters to separate the species of Chondrilla. Moreover, to determine if the differences in spicule dimensions previously found were seasonal, we also quantified the diameter of the spherasters throughout the year. Our results demonstrate that all analysed characters are extremely variable and that spicule size can vary even at the same locality. The present study shows the importance of testing the variability of morphological characters before describing new species. Unfortunately, until valid taxonomic characters are found, the Atlantic Chondrilla species will have to remain undescribed.

The patterns of genetic differentiation and levels of genetic diversity among striped dolphin (Stenella coeruleoalba) populations from the North Atlantic Ocean (N=45 individuals) and the central and western Mediterranean Sea (N=78) were investigated using five polymorphic microsatellite loci. A North Pacific sample (N=14) was added as an out-group. Two of the markers were tetranucleotide repeats tested for the first time in this species. The Mediterranean, Atlantic and Pacific samples displayed a mean number of alleles per locus of 11.2, 13.4, and 9.6 respectively, suggesting a high but variable polymorphism across loci. The Mediterranean sample displayed particular characteristics: (i) the lowest allelic richness and expected heterozygosity (HeMediterranean=0.76, while HeAtlantic=0.83 and HePacific=0.85); (ii) a significant departure from Hardy–Weinberg equilibrium (P<0.001; FIS=0.050); and (iii) a significant linkage disequilibrium between two pairs of loci. These last two features, present neither in the Atlantic sample nor in the Pacific one, suggest that the western Mediterranean population might possibly be further subdivided. Significant genetic differentiation was detected between the Mediterranean and Pacific populations, and between the Mediterranean and Atlantic populations. However, pairwise Wright's FST was not significantly different from zero between the two geographically isolated Atlantic and Pacific populations.