Long-term population dynamics of three-spined stickleback Gasterosteus aculeatus in the White Sea during the 20th century has patterns similar to that of eelgrass Zostera marina. In this study we address possible mechanisms of such association through analysis of spatial distribution of juvenile stickleback in the wild and their substrate preferences in experimental conditions. Samples from different habitats (Z. marina, Fucus spp.) in 13 localities of Kandalaksha Bay have shown that the juvenile sticklebacks occurred mainly in the eelgrass beds. Their density was significantly lower in fucoids. In the experiments, carried out in August 2008–2009, the juveniles were offered the following types of substrates: brown macroalgae (dense and scarce), eelgrass and control (no substrate). In the experiments sticklebacks also showed a tendency to prefer eelgrass to fucoids, even if the density of the latter was higher. This may explain their higher densities associated with eelgrass in the wild.

Spatial distribution patterns of microzooplankton (0.055–0.3 mm) biomass and abundance were studied in relation to the hydrographic situation and the local flow field in the waters off Ampère and Senghor, two shallow seamounts in the subtropical and tropical NE Atlantic, in comparison with unaffected open ocean reference sites. Ampère was sampled during November/December 2010 and Senghor during December 2011 and February 2013. The study includes taxonomic composition, abundance of meroplanktonic larvae and an estimation of the respiratory carbon demand. Biomass (dry weight) standing stocks of microzooplankton in the upper 100 m ranged between 30–120 mg m−2 over Ampère and 140–260 mg m−2 over Senghor Seamount, corresponding to 33 and 24% of the total zooplankton (0.055–20 mm). Highest total abundance was always found in the upper 50 m with numbers of 1070–5060 Ind m−3 at Ampère and 5050–20,000 Ind m−3 at Senghor with microzooplankton contributing 70–95%. Zooplankton accumulated mainly at the thermocline coincident with the deep fluorescence maximum and was ascertained by food supply rather than by oxygen limitation. The microzooplankton contribution to the total respiratory carbon demand was ~50% in the subtropical waters off Ampère and ~30% at Senghor, reflecting the important role of microzooplankton in the waters of the NE Atlantic subtropical gyre. Clear evidence of local seamount effects resulting in enhanced microzooplankton biomass compared with the unaffected reference sites were not detected. However, we confirmed Senghor as a hotspot for meroplanktonic larvae, suggesting a retention potential that results in significantly enhanced larval abundance in the seamount waters as compared with the open ocean.

The movement and activity patterns of the nurse shark, Ginglymostoma cirratum, a vulnerable species off Brazil, were investigated using mark-recapture and acoustic telemetry at an oceanic insular Marine Protected Area, the Fernando de Noronha Archipelago, Brazil. A total of 93 sharks were captured and tagged, ranging from 82 to 265 cm of total length (TL). Nurse sharks were captured throughout the year, and all life-stages used the insular shelf. Fifteen sharks (16% of the total) were recaptured after periods at liberty ranging from 3.5 h to 705 days, and the distances between tag and recapture locations ranged from 0.07 to 3.5 km. Site fidelity and movements of 10 sharks ranging from 107 to 265 cm TL were investigated for 18 months with an array of automated telemetry receivers. The mean period of detection of the monitored sharks was 66 days, ranging from 13 to 119 days. One individual 158 cm TL was monitored with active tracking for 17 days, with distances between daily locations ranging from 0.84 to 3.32 km, exhibiting movements similar to those of sharks monitored by automated telemetry. Despite remaining motionless or exhibiting short range movements for several hours or days, nurse sharks can be relatively wide-ranging, and protected areas alone cannot be the only conservation measure used to protect this species, which requires a set of protective measures, including fisheries management.

pCO2/pH perturbation experiments were carried out under two different pCO2 levels to evaluate effects of CO2-driven ocean acidification on semi-continuous cultures of the marine diatom Skeletonema pseudocostatum CSA48. Under higher pCO2/lowered pH conditions, our results showed that CO2-driven acidification had no significant impact on growth rate, chlorophyll-a, cellular abundance, gross photosynthesis, dark respiration, particulate organic carbon and particulate organic nitrogen between CO2-treatments, suggesting that S. pseudocostatum is adapted to tolerate changes of ~0.5 units of pH under high pCO2 conditions. However, dissolved organic carbon (DOC) concentration and DOC/POC ratio were significantly higher at high pCO2, indicating that a greater partitioning of organic carbon into the DOC pool was stimulated by high CO2/low pH conditions. Total fatty acids (FAs) were significantly higher under low pCO2 conditions. The composition of FAs changed from low to high pCO2, with an increase in the concentration of saturated and a reduction of monounsaturated FAs. Polyunsaturated FAs did not show significant differences between pCO2 treatments. Our results lead to the conclusion that the balance between negative or null effect on S. pseudocostatum ecophysiology upon low pH/high pCO2 conditions constitute an important factor to be considered in order to evaluate the global effect of rising atmospheric CO2 on primary productivity in coastal ocean. We found a significant decrease in total FAs, however no indications were found for a detrimental effect of ocean acidification on the nutritional quality in terms of essential fatty acids.

Recent events in world politics demonstrate that a part of society has lost faith in their institutions. The importance of facts and evidence in citizens’ decision making is weakened by opinions and belief systems. This post-fact or alternate facts era is a new challenge in the field of science communication as we urgently need to tackle global environmental challenges. Not only do scientists need to better communicate their work, they also need to explore alternative ways of transferring knowledge to help citizens reconnect with nature and actively take responsible decisions to protect it. The activity ‘I am the Ocean’ has been developed by an artist and a scientist with the goal to help students understand, connect and be equipped to take actions on marine global changes. The activity was a mix of field trips, open discussions and sensory immersion. It illustrates how art and metaphors can add an emotional and physical dimension to science communication, allowing a better understanding of otherwise invisible threats, and move from knowledge to passion.

The mole crab Emerita brasiliensis inhabits exposed sandy beaches, both reflective and dissipative, along the Atlantic coast of South America, where it usually attains high biomass and production. We assessed the effects of physical characteristics of beaches (mean grain size, beach width and slope) on production and turnover rate (P/B ratio) of E. brasiliensis. Six production and P/B ratio datasets, estimated with cohort-based and size-based methods, were gathered from studies carried out on subtropical (~25°S) and temperate beaches (~32°S). Based on the estimates available, general trends were identified. Production was positively related to the intermediate/dissipative conditions of wider beaches with finer sand grains and gentler slopes. P/B ratio was negatively related to grain size (mm) and positively related to beach width. These results suggest that P/B ratios also increase towards intermediate/dissipative features due to higher growth rate, as indicated by higher values of the curvature parameter of the von Bertalanffy growth function (K) in more benign conditions (wider beaches with finer grains). In addition, the recurrent pattern of size structure on intermediate/dissipative beaches, with high frequency of recruits, leads to higher P/B ratio estimates on these beaches than on reflective beaches. The relationship of production and P/B ratio with physical features, such as mean grain size, beach width and slope indicates that a ‘short-cut’ approach to estimate Emerita brasiliensis production is a promising prospect and, therefore, more data on the production of this species should be provided.

Recent studies have improved our understanding of nearshore marine ecosystems surrounding Ascension Island (central Atlantic Ocean), but little is known about Ascension's benthic environment beyond its shallow coastal waters. Here, we report the first detailed physical and biological examination of the seabed surrounding Ascension Island at 100–1000 m depth. Multibeam swath data were used to map fine scale bathymetry and derive seabed slope and rugosity indices for the entire area. Water temperature and salinity profiles were obtained from five Conductivity, Temperature, Depth (CTD) deployments, revealing a spatially consistent thermocline at 80 m depth. A camera lander (Shelf Underwater Camera System; SUCS) provided nearly 400 images from 21 sites (100 m transects) at depths of 110–1020 m, showing high variability in the structure of benthic habitats and biological communities. These surveys revealed a total of 95 faunal morphotypes (mean richness >14 per site), complemented by 213 voucher specimens constituting 60 morphotypes collected from seven targeted Agassiz trawl (AGT) deployments. While total faunal density (maximum >300 m−2 at 480 m depth) increased with rugosity, characteristic shifts in multivariate assemblage structure were driven by depth and substratum type. Shallow assemblages (~100 m) were dominated by black coral (Antipatharia sp.) on rocky substrata, cup corals (Caryophyllia sp.) and sea urchins (Cidaris sp.) were abundant on fine sediment at intermediate depths (250–500 m), and shrimps (Nematocarcinus spp.) were common at greater depths (>500 m). Other ubiquitous taxa included serpulid and sabellid polychaetes and brittle stars (Ophiocantha sp.). Cold-water corals (Lophelia cf. pertusa), indicative of Vulnerable Marine Ecosystems (VMEs) and representing substantial benthic carbon accumulation, occurred in particularly dense aggregations at <350 m but were encountered as deep as 1020 m. In addition to enhancing marine biodiversity records at this locality, this study provides critical baseline data to support the future management of Ascension's marine environment.

Polymorphism may allow individuals to expand habitat use through morph-specific resource demands. However, the underlying mechanisms maintaining different morphotypes in nature are difficult to identify. We sampled populations of the shrimp Hippolyte obliquimanus in the macroalgae Sargassum furcatum and Galaxaura marginata to examine morph-specific distribution patterns, population structure and female reproductive output, as an initial step to understand polymorphism in this species. Two main colour morphotypes were identified: homogeneous shrimps (H), which change their colour, mostly from pink to greenish-brown tones, and striped translucent shrimps (ST), whose colour remain unaltered. Distribution of individuals between habitats was clearly morph-specific. H shrimps occupied colour-matching substrates, mainly Sargassum, where they can attain large densities, and ST individuals were evenly distributed in both algae. Brood production and size-fecundity relationships were similar between morphs and habitats, suggesting these are relatively fixed traits in the population. However, sex proportions, defined as the male to female ratio, were different between morphs and macroalgae. H shrimps were chiefly females (1:2.04) and ST shrimps mostly males (1:0.30). Given the likely polygynic pure-search mating system in H. obliquimanus, the female-biased sex ratio observed in Sargassum is apparently more advantageous than the Mendelian proportion found in Galaxaura habitat. Clustering on vegetated habitat, the female-biased H morph may be relatively cryptic and sedentary, compared with the male-biased ST morph which apparently combines a more neutral camouflage strategy to a generalized habitat use. Altogether, results suggest that selection for sex-specific traits favours the maintenance of polymorphism in H. obliquimanus.

The results of an investigation into coelenteron content of the Antarctic sea anemone Urticinopsis antarctica Carlgren, 1927 are presented. Remains of invertebrate animals and fishes were found in the gastrovascular cavity of anemones. Some of them were damaged by digestion and were considered as food items of U. antarctica. These items were molluscs Addamussium colbecki (Smith, 1902), Laevilacunaria pumilia Smith, 1879, Eatoniella caliginosa Smith, 1875 and one not strictly identified gastropod species from the family Rissoidae; a crinoid from the family Comatulida; sea-urchin Sterechinus neumayeri Meissner, 1900; ophiuroid Ophiurolepis brevirima Mortensen, 1936 and a fish Trematomus sp. In contrast to the prey mentioned above, three specimens of amphipods Conicostoma sp. were not destroyed by digestion. They may represent commensals, which live in the gastrovascular cavity of the anemone.

Ecological classification of coastal waters has become increasingly important as one of the basic issues in the biology of conservation. Management and protection of coastal areas take place at different spatial scales. Thus, proper classification schemes should integrate equivalent information at various levels of definition in order to show its feasibility as a useful tool for assessment of coastal environments at the required scales. In this work, a global approach applied to the classification of the NE Atlantic coast is analysed in order to discuss pros and cons regarding different conceptual and technical issues for effective implementation of such a management tool. Using the hierarchical system applied at three different geographic scales: Biogeographic (NE Atlantic coast), Regional (Bay of Biscay) and Local (Cantabria region), five different topics were considered for debating strengths and weaknesses of the methodological alternatives at those spatial scales, using for validation the rocky shore macroalgae as a representative biological element of benthic communities. These included: (i) the spatial scales; (ii) the physical variables and indicators; (iii) the classification methodologies; (iv) the biological information; and (v) the validation procedure. Based on that analysis, the hierarchical support system summarized in this paper provides a management framework for classification of coastal systems at the most appropriate resolution, applicable to a wide range of coastal areas. Further applications of the physical classification for management of biodiversity in different environmental scenarios are also analysed.

Paramya is an enigmatic genus of Myidae (Bivalvia: Heterodonta: Myoidea) that includes three uncommon species: Paramya subovata (Conrad, 1845), Paramya recluzi (A. Adams, 1864) and Paramya africana Cosel, 1995. Paramya subovata is known as a commensal living in the burrow of the spoon worm Thalassema hartmani Fisher, 1947 (Annelida: Echiura: Thalassematidae), in North American coastal waters. However, the biology of the other two species remains unknown. In this study, we found P. recluzi living in the burrows of the two thalassematid echiuran species, Ikedosoma gogoshimense (Ikeda, 1904) and Arhynchite hayaoi Tanaka & Nishikawa, 2013, in intertidal flats in the Seto Inland Sea, Japan. Paramya recluzi was embedded in the burrow wall with its short siphons protruding into the host burrow lumen for respiration and filter feeding. To determine the phylogenetic position of P. recluzi, we performed a molecular phylogenetic analysis using the 18S, 28S, COI and H3 genes. Molecular analysis showed that P. recluzi belongs not to the family Myidae, but to the genus Basterotia (Galeommatoidea: Basterotiidae). Morphological examination of P. recluzi revealed that this species has many similarities with Basterotia (e.g. a single cardinal tooth on each valve and short siphons surrounded by tentacles). Thus, we propose that this species should be transferred from the genus Paramya to Basterotia. In addition, we also suggest that the other two species of Paramya (P. subovata and P. africana) should be transferred to the family Basterotiidae based on their shell morphology, anatomy and ecological characteristics.

The primarily bathypelagic gonostomatid Cyclothone microdon, amongst the most abundant of all vertebrates, remains poorly known. We describe its diet in The Gully, a very large submarine canyon off Nova Scotia, Canada, based on the stomach contents of specimens caught by midwater trawl. In The Gully, C. microdon had a shallower distribution than in open ocean and primarily fed at mesopelagic depths. Most of its diet comprised vertically migrant calanoid copepods, while its secondary prey was conchoeciinid ostracods. Both were typical of the food eaten in other regions by its mesopelagic congeners and were consistent with the results of the only previous dietary study of C. microdon.

Fungal emerging pathogens are one of the main threats for global biodiversity. Sea turtles do not seem to be an exemption, and recent studies on important nesting areas worldwide have shown that two fungal pathogens, i.e. Fusarium falciforme and Fusarium keratoplasticum, are involved in low hatching success in nests of sea turtle species. Although the presence of these pathogens has been detected in Ascension Island, there are no investigations on the distribution of these two pathogens in main nesting beaches in the island. In this study, we analysed 109 eggshells of the species Chelonia mydas from four nesting areas in Ascension Island. We have isolated and identified a total of 46 fungal isolates. A phylogenetic analysis, of the ITS nrDNA region, with a number of reference sequences of the Fusarium solani species complex, showed that 23 of these isolates corresponded to the pathogen F. keratoplasticum. The analyses on isolation frequency, that included other previously obtained isolates, i.e. 11 F. keratoplasticum and one F. falciforme, showed that F. keratoplasticum was the species most frequently isolated in Ascension Island and it was found in all nesting beaches, while F. falciforme was only isolated from Pan Am beach. When compared with other nesting areas worldwide, the abundance of F. keratoplasticum over F. falciforme was higher than any other nesting region tested. These findings are important in order to evaluate the potential threat of this pathogen to nests of the sea turtle population of Ascension Island, and to develop future control strategies.

The common prawn (Palaemon serratus) supports a small-scale but economically important seasonal static-gear fishery in Cardigan Bay, Wales (UK). Due to a lack of statutory obligation and scientific evidence, the fishery has operated to date without any harvest-control rules that afford protection from overfishing. In response to fluctuations in landings and in pursuit of increased economic returns for their catch, some members of the fishing industry have adopted a size-selective harvesting regime, which we evaluate here using baseline data. Monthly samples were obtained from fishers operating out of five ports between October 2013 and May 2015 (N = 4233). All prawn were sexed, weighed and measured, whilst the fecundity of females was estimated for 273 (44%) individuals. Peak spawning occurred during the spring and females were estimated to undergo a ‘puberty moult’ at a carapace length (CL) of 7.7 mm, whilst functional maturity was estimated at a CL of 9.9 mm. The sampled population exhibited sexual dimorphism, with females attaining a greater size than males. The current harvesting regime results in a sex bias in landings as even large mature males remained under the recruitment size to the fishery, unlike the large mature females. The temporal trend in sex-ratio indicates a continual decrease in the catchability of female prawn through the fishing season; however, whether this is caused by depletion via fishing mortality or migratory behaviour is yet to be resolved. Here, we provide a comprehensive baseline evaluation of population biology and discuss the implications of our findings for fisheries management.

Quantifying exchange of particulate matter between coastal and open waters is an important and often unresolved issue. Here, we apply phytoplankton order richness as an innovative marine tracer to identify the geographic position of a coastal exchange zone in the SE North Sea, including its variability in time and space. Previous observations on dynamics of suspended particulate matter accumulation resulted in a hypothesized boundary between coastal waters (including the Wadden Sea) and open North Sea waters, the so-called ‘line-of-no-return’. Our study along two transects (Terschelling, Noordwijk) in the Dutch coastal zone showed seasonality patterns in phytoplankton order richness, both for diatoms and flagellates. The coastal Wadden Sea was found to be clearly different from the open North Sea, implying that seasonality in Wadden Sea phytoplankton is at least partly driven by local environmental conditions. Seasonality in flagellates was found to be more uniform than seasonality in diatoms. Stations in the coastal North Sea to a distance of 10 km (Terschelling) to 20 km (Noordwijk) from the shore appeared to be at the inside of the ‘line-of-no-return’. Our findings indicate that this approach is a useful aid in exploring mixing of particulate matter between coastal and open waters and to study the responses of phytoplankton communities to environmental drivers.

An area in the central North Sea was surveyed in November 2011 in order to estimate the abundance and density of harbour porpoises (Phocoena phocoena). A total of 2833 km of pre-determined trackline were acoustically surveyed, of which 28% included visual effort. The poor sighting conditions during the survey limited visual effort and demonstrated the advantage of using acoustic techniques for studying harbour porpoise in winter months. Absolute abundance and density estimates were calculated from acoustic encounter rates using estimates of probability of detection and mean group size. The density of harbour porpoises in the west of the survey area was almost double that in the east, with UK waters to the south-west of the Dogger Bank having the highest density of the area surveyed. The overall acoustic encounter rate was higher than most other surveys in the North Sea. The mean density across the survey area of 0.63 (95% CI 0.27–1.52) individuals km−2 and distribution of porpoises was similar to that documented in the summer suggesting that high abundance of harbour porpoises in the west of the North Sea is not confined to summer months. This information is particularly relevant given plans for the construction of a large offshore wind farm on the UK section of the Dogger Bank; the resulting impacts, including acoustic disturbance from pile driving, will potentially affect substantial numbers of harbour porpoises.