Long-term tagging studies, particularly those that target life stages away from nesting beaches can provide important insights in key life history traits, which are essential for the effective management of endangered species. The coast of Bahia hosts important green turtle foraging areas, but information on demography, spatial use and foraging ecology in this region is lacking. Here, we (1) examined the size-class structure of green turtles in Bahia, (2) compared the size distribution from Bahia to other foraging aggregations in Brazil, and (3) studied the somatic growth dynamics. Additionally, we investigated the (4) diet, (5) habitat use and (6) activity patterns of green turtles along shallow reefs in Bahia. From 2009 to 2013, 322 green turtles were captured and 44 were recaptured between 7 and 1218 days after initial tagging. Curved carapace length varied from 32.9 to 122.5 cm. Mean annual growth rate was 3.03 ± 1.18 cm year−1. The diet of the turtles was mainly composed of red algae of the family Gelidiaceae, Gelidiellaceae and Cystocloniaceae. There was a positive relationship between the abundance of red algae and the number of turtle sightings, with a significant increase in foraging activity during late afternoon. This study highlights the importance of this area as a mixed foraging aggregation of juvenile and adult green turtles, and reveals that foraging grounds for this species in Brazil exhibit southern immature-dominated assemblages and northern mixed aggregations. Areas with high aggregation of green turtles comprising individuals from different life stages must be targeted for conservation management.

Marine debris is a major challenge threatening ocean and coastal environment with no easy solution in coming years. The problem is totally manmade and extendeds to coastal areas around the world. The accumulation of marine debris is largely due to lack of awareness and environmental education among the public reinforced with mismanagement of municipal litter in coastal cities. Iran has about 2415 km of coastlines in the north and south of the country that suffer severely from a marine debris problem. Despite the great scale of the problem that leads to the shutdown of some beaches to beachgoers, there are no documented data on the abundance, composition and sources of marine debris dispersed on beaches. With the cooperation of marine biology student volunteers, we surveyed beaches at two scales, 100 m and 1 km searching for litter in varying ranges. The results revealed that the most common items are made of plastic/polystyrene. Tourism and recreational activities are responsible for more than 90% of litter production on the study beach. Fisheries and aquaculture are the second source of most abundant marine litter found on the beach with considerable distance from tourism activities. We conclude that lack of education about the consequences of marine litter is the main reason for marine debris at the study beach. Another reason is related to rapid construction of coastal areas and development of coastal cities with no proper infrastructure to manage municipal littering.

Two new demosponges, Megaciella pituitosa and Cladocroce toxifera, are described from the Aleutian Islands, fostering our contention that the region is a hotspot of poriferan biodiversity. Seven of the thirteen species of Megaciella now known worldwide occur in the Sea of Okhotsk or around the Aleutian Islands. Similarly, five of the sixteen species of Cladocroce known worldwide occur in Alaska. Megaciella pituitosa sp. nov. possesses two categories of choanosomal styles and spicules of different sizes that differentiate it from all known congeners. Cladocroce toxifera sp. nov. differs from all known congeners by possessing toxa and an ectosomal tangential arrangement of oxeas.

Sampling in subtidal waters of the Persian Gulf revealed a new species of ghost shrimp from the family Gourretiidae. Gourretia qeshmensis sp. nov. resembles G. sinica from the South China Sea and G. manihinae from Tanzania. Gourretia qeshmensis sp. nov. differs from these two species by characters of the ischium of the large cheliped, pereopod 3, exopod of the uropod and maxilliped 3.

Macroalgal communities of coastal ecosystems play a key role in maintaining overall coastal biodiversity. In this study, habitat preference (macroalgal host preference) and temporal changes (season) of epifaunal communities associated to five macroalgal species such as Padina, Sargassum, Ulva, Acanthophora and Gracilaria were observed at seasonal intervals (summer and winter) for 2 years from May 2012 to March 2014 on the Jeddah coastal waters of the Red Sea. Major epifaunal groups observed included polychaetes, amphipods, isopods, gastropods, mussels and crabs. Polychaetes were represented by 10 species followed by amphipods with five species. The abundance of gastropods, polychaetes and mussels showed significant variation between the macroalgae irrespective of morphology. Generally, the abundance of these taxa were high on Padina and low on Sargassum. Significant seasonal changes were observed on the abundance of polychaetes, amphipods and isopods. The abundance of some epifaunal groups showed a significant relationship with environmental parameters such as surface water temperature, salinity, pH and dissolved oxygen content.

The temporal variation in the taxonomic distinctness of biofilm-associated diatom microflora within the colonization process was studied in coastal waters of the Yellow Sea, northern China from May to June 2014. Samples were collected at depths of 1 and 3 m, using glass slides as an artificial substratum. The colonization dynamics of diatom microflora showed similar species composition at both depths. In the young communities (1–7 days), the taxonomic patterns showed high variability compared with those in the mature ones (10 days and more). However, taxonomic distinctness indices at the two depths differed during early stages (e.g. 1–3 days). The taxonomic diversity (Δ) represented a high variability (coefficients of variation >10%) over all colonization periods, whereas the taxonomic distinctness (Δ*), average taxonomic distinctness (Δ+) and variation in taxonomic distinctness (Λ+) showed high stability (coefficients of variation <10%) after 7 days. Based on these findings, we suggest that the exposure time of more than 7 days may be sufficient to identify the taxonomic distinctness of biofilm-associated diatom microflora for both community research and monitoring programmes in marine ecosystems.

Knowledge on the ecology of humpback whales in the eastern North Atlantic is lacking by comparison with most other ocean basins. Humpback whales were historically over-exploited in the region and are still found in low relative abundances. This, coupled with their large range makes them difficult to study. With the aim of informing more effective conservation measures in Ireland, the Irish Whale and Dolphin Group began recording sightings and images suitable for photo-identification of humpback whales from Irish waters in 1999. Validated records submitted by members of the public and data from dedicated surveys were analysed to form a longitudinal study of individually recognizable humpback whales. The distribution, relative abundance and seasonality of humpback whale sighting records are presented, revealing discrete important areas for humpback whales in Irish coastal waters. An annual easterly movement of humpback whales along the southern coast of Ireland is documented, mirroring that of their preferred prey: herring and sprat. Photo-identification images were compared with others collected throughout the North Atlantic (N = 8016), resulting in matches of two individuals between Ireland and Iceland, Norway and the Netherlands but no matches to known breeding grounds (Cape Verde and West Indies). This study demonstrates that combining public records with dedicated survey data is an effective approach to studying low-density, threatened migratory species over temporal and spatial scales that are relevant to conservation and management.

Suitable genetic markers for population studies in sponges are necessary to further our understanding of biodiversity and dispersal patterns, and contribute to conservation efforts. Due to the slow mitochondrial substitution rates in demosponges, nuclear introns are among the preferable markers for phylogeographic studies, but so far only the second intron of the ATP synthetase beta subunit-gene (ATPSβ) has been successfully established. In the present study, we analyse the intron of the Lysidyl Aminoacyl Transfer RNA Synthetase (LTRS), another potential marker to study demosponge intraspecific relationships, on samples of Neopetrosia chaliniformis from various locations in the Indo-Pacific and compare its variation with a mitochondrial marker (CO2). LTRS recovers several reciprocal monophyletic groups among the Indo-Pacific N. chaliniformis and provides a potential alternative to ATPSβ.

Dercitus (Stoeba) pseudodiscorhabda sp. nov. is described from the tropical western Atlantic. It is the only Dercitus (Stoeba) with four-rayed calthrops and discorhabds-like sanidasters. This is the 16th species of the genus to be recognized worldwide, the sixth from the Atlantic. The new species is compared with all its congeners worldwide.

We examine the relationship of biomass B and length L in the eastern oyster Crassostrea virginica by focusing on the scaling exponent b in the allometric equation B = aLb using four datasets: Delaware Bay, Chesapeake Bay, Galveston Bay and a regionally extensive compilation from the NOAA Mussel Watch Program. The average value of the scaling exponent in Delaware Bay and Chesapeake Bay is about 2. For Galveston Bay, the value is distinctly higher, near 2.6. Over all Mussel Watch sites, the value is again near 2. Within Delaware Bay, the salinity gradient exerts an important effect. Shells are longer for their meat weight at lower salinities. The range of scaling exponents revealed by Mussel Watch data is exceedingly large (b < 1 to >3). Scaling exponents below 2.5 are unusual in bivalves. Among bivalves, only other oyster taxa have comparably low scaling exponents averaging near 2. We propose that oyster biomass routinely scales nearer the square of the length rather than the cube and that this is a constraint imposed by the exigency of carbonate production for reef maintenance and accretion in the face of high rates of taphonomic degradation. The adaptation as a reef builder requires the formation of carbonate that rapidly breaks down, thus requiring that carbonate produced be maximized. A biomass-to-length scaling exponent of 2 provides a mechanism to maximize shell production relative to biomass, while at the same time providing maximum surface area for the all-important settling of oyster spat to maintain the population.

Hymedesmia (Hymedesmia) lindstroemae sp. nov. collected at 178–210 m depth off the western Swedish coast is described. This encrusting sponge is notably characterized by its unusually large sigmas. This new species brings the number of Hymedesmia (Hymedesmia) species in Swedish waters to 30. A key for all the North Atlantic Hymedesmia (Hymedesmia) species with sigmas (32 species) is included.

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.

Popularly known as blue land crab, Cardisoma guanhumi is heavily exploited as food and considered as an important economic resource in Brazil. In recent decades, the species has experienced a sharp population decline by the loss and/or degradation of its natural habitat and overfishing. The present study aimed to investigate the genetic variation and connectivity among 154 specimens of C. guanhumi sampled along the coast of Pernambuco in five different levels of tropical mangroves conservation. Nine ISSR primers were used for assessing the genetic variation of the species. The genetic diversity observed in C. guanhumi was high reinforcing the condition of a resilient species, indicating a good conservation status of this resource in Pernambuco. The hypothesis of panmixia was rejected in favour of a heterogeneous distribution of the genotypes of C. guanhumi (ФST = 0.19) despite the high gene flow observed in the study region. Such difference could be attributed to the candidate loci being under positive selection and differentially distributed between the geographic regions assessed. The genetic structure showed a pattern of fine-scale genetic structuring better fitted to a model of selection-mediated geographic cline. Cluster analysis and candidate loci under positive selection suggested that the populations of C. guanhumi in the North-central and South coasts of Pernambuco might be different management units and must be managed independently. In conclusion, exhaustion of natural stocks upon which fishing is totally dependent will lead to serious ecological and sociocultural impacts.

Nanoparticles have applications in a diverse range of products including medications, detergents, cosmetics, paint, sunscreen and electronics, with an economic worth projected to reach $2.5 trillion dollars in 2015. Research into the effects of manufactured nanomaterials on the environment, however, has failed to keep pace with the high volume of commercial production. Whereas a number of studies have examined the effects of nanoparticles on aquatic species, little work has focused on the way in which benthic marine species encounter, ingest and depurate these materials. The purpose of this study was to examine the ingestion and depuration of titania nanoparticles (anatase) by the blue mussel (Mytilus edulis) and the eastern oyster (Crassostrea virginica) during a spill scenario (an acute exposure to elevated concentrations). Bivalves were exposed to nanoparticles either incorporated into marine snow, an environmentally relevant medium for pollutants, or added directly to seawater at a concentration of 4.5 mg L−1 for 2 h. After feeding, the animals were transferred to filtered seawater and allowed to depurate. Faeces and tissues were collected at 0, 6, 24, 72 and 120 h, post-exposure, and analysed for concentrations of titanium by inductively coupled plasma-mass spectrometry. Results indicated that the capture and ingestion of titania nanoparticles by both species was not dependent on the method of delivery (incorporated into marine snow or freely suspended). Additionally, greater than 90% of the titania nanoparticles, on average, were eliminated from the tissues after 6 h, and only trace amounts remained after 72 h. These data demonstrate that mussels and oysters readily ingest titania nanoparticles, but rapidly depurate the material within hours of an acute exposure suggesting that little would be transferred to secondary consumers including humans. Further research is required to determine if other species of suspension-feeders handle titania nanoparticles in a manner similar to bivalves.

A novel species of nematode belonging to the rare genus Psammonema Verschelde & Vincx, 1995 is described from the continental margin of the north-eastern Arabian Sea (214 m). Psammonema kuriani sp. nov. shows a different position of the lateral alae compared with the original genus diagnosis, hence an emended genus diagnosis is given. The genus Psammonema was previously described from the estuarine sediments of Indian Ocean region and the present study reports the genus from the deep sea for the first time.

During the last decades, the Mediterranean shallow-water benthic communities have experienced significant changes in taxa composition and distribution. These variations were related to a complex set of anthropogenic stressors as well as to mass mortality events starting from 1999 and related to the current climatic changes. To evaluate the effect of these changes on long-living species with a limited larval dispersal capacity, a quantitative and qualitative monitoring of the shallow-water hard bottom community structure was performed over a pluri-decennial interval of time. The aim of this work was the comparison of the quali-quantitative occurrence and seasonal cycles of several benthic taxa living on a rocky cliff of the Portofino Promontory (eastern Liguria, Mediterranean Sea), from 15 to 20 m depth. The studied community, within a Lithophyllo–Halimedetum tunae association, was analysed by sets of photographs repeated, exactly in the same site, at 25 years of distance (1987/88 and 2012/13). The results suggest that the macroalgal coverage of the surveyed cliff suffered, during the monitored span of time, a significant depletion in quali-quantitative terms, while the overall sponge coverage remained almost unvaried. Nevertheless, a discrete analysis of the most common sponge species present in the study area showed significant variations, with some taxa now more abundant (Axinella spp. and Agelas oroides), some virtually stable (Cliona viridis and the complex of red encrusting sponges), and others drastically depleted (Chondrosia reniformis, Phorbas tenacior, Acanthella acuta, Ircinia spp., Dysidea avara and Petrosia ficiformis). Finally, some sponge species showed clear seasonal cycles indicating recruitment periods and post-recruit mortalities.

Didiscus gladius sp. nov. is described from Bahia State (Brazil). The sponge is thinly encrusting to lump-shaped and has a glassy, translucent appearance, through which the spiculation is clearly visible. The megascleres are styles and two categories of oxeas. The microscleres are discorhabds. Colour is beige or brown in ethanol. Didiscus verdensis is the nearest relative in the Atlantic which differs from the new species in a series of traits (e.g. absence of true styles and presence of strongyles). A key to species of Didiscus is given.

Zoantharians are one of the least studied orders of benthic cnidarians of the Persian Gulf. A survey and molecular analysis was conducted to determine zoantharian species diversity in the Persian Gulf. For this purpose, 63 colonies of zoantharians were collected from Hengam and Larak Islands in the Strait of Hormuz and some morphological characteristics of each specimen were recorded, i.e. sand encrustation, polyp shape and colour, oral groove, oral zone and oral disc colours as well as tentacle number and colour. After DNA extraction, mitochondrial 16S ribosomal DNA (16S rDNA) and cytochrome oxidase subunit I (COI) were amplified by polymerase chain reaction (PCR). Based on obtained 16S rDNA and COI gene sequences, five putative species-level clades were identified: Zoanthus sansibaricus (N = 30), Palythoa tuberculosa (N = 12), Palythoa mutuki (N = 2), Palythoa aff. mutuki (N = 18) and Neozoanthus sp. Iran (N = 1). While the first three are known species, the last two were potentially novel undescribed species. Palythoa aff. mutuki has an external appearance similar to Palythoa mutuki. However, mitochondrial DNA sequences obtained from these specimens placed them in a previously undescribed species group. The Neozoanthus specimen was morphologically and molecularly different from other described Neozoanthus species. This is the first record of this genus from the Persian Gulf and neighbouring areas. Since there is not much work on zoantharians identification in the Persian Gulf, further sampling and investigation is needed to speculate on the accuracy of these potentially new species and to complete the knowledge of zoantharian diversity in this area.

A new species of tube-dwelling anemone of the genus Ceriantheopsis (Cnidaria: Ceriantharia), Ceriantheopsis lineata sp. nov., is described and can be found in fine sand or mud in the sublittoral zone (0–200 m) from Argentina to Brazil (Warm Temperate South-western Atlantic). This new species is distinguished from its congeners by a number of features, however some characters (directive tentacles, line on tentacles and length of P2) allow a conclusive identification among the other Ceriantheopsis species.

The identification of foraging hotspots able to support the co-existence of multiple top predators provides a potential approach to addressing protection measures for marine ecosystems. In this study, we conducted visual surveys in the central Tyrrhenian Sea to determine areas with simultaneous presence of bottlenose dolphins, four species of seabirds (Audouin's gull, Yellow-legged gull, Yelkouan shearwater and Cory's shearwater), and baitballs occurring at the surface, indicating the presence of potential prey items. We also analysed their occurrence in relation to topography (depth, slope and distance from the shore) and seabed types. Kriging analysis identified areas with simultaneous presence of several marine top predators. Dolphin distribution appeared to be linked to gentle slope (6–10 m) and muddy seabed, possibly associated with prey distribution, whereas the four seabird species were more frequent in areas with a water depth of 100–150 m, gentle slope and muddy seabed, apart from Audouin's gull, which preferred a depth of 10–20 m. Baitball distribution was linked to depth (20–40 m), gentle slope (6–10 m) and muddy seabed. The overlapping presence of bottlenose dolphins, seabirds and baitballs allowed the identification of foraging areas, presumably representing biodiversity and productivity hotspots, located in waters of 50–100 m depth at the mouths of two rivers. This approach provides a promising tool for identifying highly productive coastal areas, and should also be recommended for wider-scale surveys.