@article {8692, title = {Can~artificial~magnetic~fields~alter the~functional~role~of~the blue mussel, Mytilus edulis?}, journal = {Marine Biology}, volume = {169}, year = {2022}, month = {Jan-06-2022}, abstract = {Along European coasts, the rapid expansion of marine renewable energy devices and their buried power cables, raises major societal concerns regarding the potential effects of their magnetic field emissions (MFs) on marine species and ecosystem functioning. MFs occur at a local spatial scale, which makes sessile species the primary target of chronic and high-intensity exposures. Some of them, as ecosystem engineers, have critical functions in coastal habitats whose behavioral alteration may drive profound consequences at the ecosystem level. In this context, the present experimental study explored the effects of short exposure to direct current MFs, on the feeding behavior of a widespread ecosystem engineer, the blue mussel (Mytilus edulis). A repeated measure design was carried out with adult mussels successively exposed to control treatment (ambient magnetic field of 47 μT) and artificial MF treatment (direct current of 300 μT produced by Helmholtz coils), as measured around power cables. The filtration activity was assessed through valve gap monitoring using an automated image analysis system. The clearance rate was estimated simultaneously by measuring the decrease in algal concentration using flow cytometry. Our findings revealed that mussels placed in MF treatment did not exhibit observable differences in valve activity and filtration rate, thus suggesting that, at such an intensity, artificial MFs do not significantly impair their feeding behavior. However, additional research is required to investigate the sensitivity of other life stages, the effects of mid to long-term exposure to alternative and direct current fields and to test various MF intensities.}, keywords = {Coastal environments, Ecosystem engineers, Filter-feeders, Magnetic fields, Mytilus edulis, Submarine power cables}, issn = {0025-3162}, doi = {10.1007/s00227-022-04065-4}, url = {https://link.springer.com/10.1007/s00227-022-04065-4}, author = {Albert, Luana and Maire, Olivier and Fr{\'e}d{\'e}ric Olivier and Lambert, Christophe and Romero-Ramirez, Alicia and Jolivet, Aur{\'e}lie and Chauvaud, Laurent and Chauvaud, Sylvain} } @article {8448, title = {Insights into the behavioural responses of juvenile thornback ray}, journal = {Journal of Fish Biology}, year = {2022}, month = {Apr-01-2022}, abstract = {As part of energy transition, marine renewable energy devices (MRED) are currently expanding in developed countries inducing the deployment of dense networks of submarine power cables. Concern has thus raised about the cable magnetic emissions (direct or alternating current) because of potential interference with the sensorial environment of magneto-sensitive species, such as sharks and rays. This study sought to assess the short-term behavioural responses of juvenile thornback rays (Raja clavata) (n = 15) to direct and alternating (50 Hz) uniform 450-μT artificial magnetic fields using 1 h focal-sampling design based on a detailed ethogram. Careful control of magnetic fields{\textquoteright} temporal and spatial scales was obtained in laboratory conditions through a custom-made Helmholtz coil device. Overall, qualitative or quantitative behavioural responses of juvenile rays did not significantly vary between control vs. exposed individuals over the morning period. Nonetheless, rays under direct current magnetic field increased their activity over the midday period. Synchronisation patterns were also observed for individuals receiving alternating current exposure (chronologic and qualitative similarities) coupled with a high interindividual variance. Further studies should consider larger batches of juveniles to address the effect of long-term exposure and explore the sensitivity range of rays with dose-response designs.}, issn = {0022-1112}, doi = {10.1111/jfb.14978}, url = {https://onlinelibrary.wiley.com/doi/10.1111/jfb.14978}, author = {Albert, Luana and Fr{\'e}d{\'e}ric Olivier and Jolivet, Aur{\'e}lie and Chauvaud, Laurent and Chauvaud, Sylvain} } @article {8739, title = {Passive acoustics suggest two different feeding mechanisms in the Atlantic walrus (Odobenus rosmarus rosmarus)}, journal = {Polar Biology}, year = {2022}, month = {Sep-06-2023}, abstract = {The vocal repertoire of walruses has been widely described in the bioacoustic literature. These marine mammals produce several distinct types of vocalizations for intraspecific communication during the breeding season. In this study, we provide the first evidence of walrus-generated sounds during foraging dives when they feed on bivalves. We recorded two types of sounds that we associated to different feeding mechanisms. The first sound type was brief and low in frequency that we relate to the suction of soft parts from the bivalves{\textquoteright} shells through the use of walrus powerful tongues, which is the common feeding behavior reported in the walrus literature. We also recorded a second sound type composed of multiple broadband pulse trains. We hypothesize the latter were associated with bivalve shell cracking by walruses, which would represent a new feeding mechanism in the walrus literature. This new feeding mechanism is either related to bivalves{\textquoteright} ecology or to walruses removing the sediment when searching for food. During this study, we observed bivalves lying on the seafloor instead of being buried in the sediment in walrus feeding areas while scuba diving. As a result, walruses cannot use suction to feed on soft body part of bivalves and have to use another strategy, mastication. Our findings provide a first step towards using passive acoustics to quantify walrus behavior and feeding ecology.}, keywords = {Bioacoustics, bivalves, Feeding Behavior, Marine mammal, Young Sound fjord}, issn = {0722-4060}, doi = {10.1007/s00300-022-03055-y}, url = {https://link.springer.com/10.1007/s00300-022-03055-y}, author = {J{\'e}z{\'e}quel, Youenn and Mathias, Delphine and Fr{\'e}d{\'e}ric Olivier and Amice, Erwan and Chauvaud, Sylvain and Jolivet, Aur{\'e}lie and Bonnel, Julien and Sejr, Mikael K. and Chauvaud, Laurent} } @article {8447, title = {Pull the trigger: interplay between benthic and pelagic cues driving the early recruitment of a natural bivalve assemblage}, journal = {Ecosphere}, volume = {13}, year = {2022}, month = {Jan-01-2022}, abstract = {Larval settlement and recruitment are crucial phases in the benthic-pelagic life cycle of marine benthic invertebrates that controls population dynamic and habitat connectivity. Our study investigated potential triggers driving the settlement of bivalve larvae in a highly dynamic intertidal coarse sand habitat. The early recruitment rate of five dominant bivalve families and abiotic conditions, particulate (\<20 {\textmu}m) organic matter and sediment organic matter, were monitored from May to October 2014. Pelagic particulate organic matter (\<20 {\textmu}m) was dominated by picoplankton throughout the sampling period, with a substantial diatom bloom in spring. Sediment was characterized by fresh organic matter in spring, as suggested by the dominant contribution of polyunsaturated fatty acids, and by a higher proportion of bacterial fatty acid markers during late summer. Different dynamics were also observed in early bivalve recruitment rates, with four different patterns observed over the sampling period. Multiple regression analysis on selected bivalve families showed species-specific responses to trophic settlement triggers. Indeed, the larva recruitment rate of Mytilidae paralleled pelagic concentration of picoeucaryotes, with the peak early recruitment rate occurring in spring. Surprisingly, the early recruitment rate of Mactridae larvae showed a significant relation to bacterial concentration in the surficial sediment at the end of summer. While the Mytilidae results in such a eutrophic system confirmed those of a previous study in oligotrophic lagoons, therefore supporting the trophic settlement trigger hypothesis, more work is needed to understand the potential role of bacteria in the early recruitment of Mactridae. These results highlight for the first-time inter-specific differences in trophic cues that potentially trigger primary settlement in natural bivalve assemblages.}, keywords = {bacteria, bivalves, Chausey Archipelago, early larval recruitment, fatty acids, picoeucaryotes, trophic settlement trigger}, issn = {2150-8925}, doi = {10.1002/ecs2.v13.110.1002/ecs2.3672}, url = {https://onlinelibrary.wiley.com/toc/21508925/13/1}, author = {Androuin, Thibault and Barbier, Pierrick and Foret, Martin and Tarik Meziane and Thomas, Mathilde and Archambault, Philippe and Winkler, Gesche and Tremblay, Rejean and Fr{\'e}d{\'e}ric Olivier} } @article {8948, title = {Rare earth elements and yttrium in suspension-feeding bivalves (dog cockle, Glycymeris glycymeris L.): Accumulation, vital effects and pollution}, journal = {Geochimica et Cosmochimica Acta}, volume = {339}, year = {2022}, month = {Jan-12-2022}, pages = {12 - 21}, issn = {00167037}, doi = {10.1016/j.gca.2022.10.033}, url = {https://linkinghub.elsevier.com/retrieve/pii/S001670372200583X}, author = {Barrat, Jean-Alix and Chauvaud, Laurent and Fr{\'e}d{\'e}ric Olivier and Poitevin, Pierre and Bayon, Germain and Ben Salem, Douraied} } @article {7804, title = {Food source diversity, trophic plasticity, and omnivory enhance the stability of a shallow benthic food web from a high-Arctic fjord exposed to freshwater inputs}, journal = {Limnology and Oceanography}, volume = {66}, year = {2021}, month = {01/2021}, pages = {S259-S272}, type = {Research}, abstract = {
Under climate change, many Arctic coastal ecosystems receive increasing amounts of freshwater, with ecological consequences that remain poorly understood. In this study, we investigated how freshwater inputs may affect the small-scale structure of benthic food webs in a low-production high-Arctic fjord (Young Sound, NE Greenland). We seasonally sampled benthic invertebrates from two stations receiving contrasting freshwater inputs: an inner station exposed to turbid and nutrient-depleted freshwater flows and an outer station exposed to lower terrestrial influences. Benthic food web structure was described using a stable isotope approach (δ13C and δ15N), Bayesian models, and community-wide metrics. The results revealed the spatially and temporally homogeneous structure of the benthic food web, characterized by high trophic diversity (i.e., a wide community isotopic niche). Such temporal stability and spatial homogeneity mirrors the high degree of trophic plasticity and omnivory of benthic consumers that allows the maintenance of several carbon pathways through the food web despite different food availability. Furthermore, potential large inputs of shelf organic matter together with local benthic primary production (i.e., macroalgae and presumably microphytobenthos) may considerably increase the stability of the benthic food web by providing alternative food sources to locally runoff-impacted pelagic primary production. Future studies should assess beyond which threshold limit a larger increase in freshwater inputs might cancel out these stability factors and lead to marked changes in Arctic benthic ecosystems.
}, doi = {https://doi.org/10.1002/lno.11688}, url = {https://aslopubs.onlinelibrary.wiley.com/doi/abs/10.1002/lno.11688}, author = {Bridier, Guillaume and Fr{\'e}d{\'e}ric Olivier and Chauvaud, Laurent and Sejr, Mikael K. and Grall, Jacques} } @article {7181, title = {Mytilus edulis and Styela clava assimilate picophytoplankton carbon through feces and pseudofeces ingestion}, journal = {Aquaculture}, volume = {531}, year = {2021}, month = {Jan-01-2021}, pages = {735868}, abstract = {Picophytoplankton (PPP) may contribute to the bulk of primary production in nutrient-rich marine ecosystems. In this study, we quantified the capacity of blue mussels (Mytilus edulis) and clubbed tunicates (Styela clava) to exploit PPP. In the water, we introduced PPP cells that were isotopically labelled with\ 13C and using the same enrichment approach, we measured the secondary transfer (recycling) of carbon via the assimilation of pseudofeces and feces. Results show that both\ M. edulis\ and\ S. clava\ assimilate PPP carbon by ingesting PPP cells directly from water. In addition, PPP assimilation rates were similar in both species. Most interesting was our observation that both species assimilated PPP carbon contained in pseudofeces and feces, including large fecal pellets produced by\ S. clava.\ We conclude that within cultured and invasive filter feeders, PPP carbon is recycled via ingestion of feces and pseudofeces among individuals growing in close proximity. In aquaculture settings, cultured bivalves and fouling tunicates may provide an ecological service by removing excess PPP in nutrient-rich systems via direct and secondary ingestion.
Keywords: Picophytoplankton, Isotopic labelling, Aquaculture, Feces, Carbon cycling, Blue mussel, Tunicate
\ }, issn = {00448486}, doi = {10.1016/j.aquaculture.2020.735868}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0044848620305779}, author = {Sonier, R. and Comeau, L.A. and Tremblay, R. and Fr{\'e}d{\'e}ric Olivier and Tarik Meziane and Genard, B.} } @article {7593, title = {Sources, quality and transfers of organic matter in a highly-stratified sub-Arctic coastal system (Saint-Pierre-et-Miquelon, NW Atlantic)}, journal = {Progress in Oceanography}, year = {2021}, month = {Jan-11-2021}, pages = {102483}, abstract = {In response to ongoing global climate change, marine ecosystems in the northwest Atlantic are experiencing one of the most drastic increases in sea surface temperatures in the world. This warming can increase water column stratification and decrease surface nutrient concentrations, in turn impacting primary productivity and phytoplankton assemblages. However, the exact impacts of these changes on sources and quality of organic matter as well as its transfers to the benthic compartment remain uncertain. This survey characterized organic matter sources and quality within a highly-stratified sub-Arctic coastal system (Saint-Pierre and Miquelon) and described its transfer towards a biomass-dominant primary consumer, the sand dollar\ Echinarachnius parma. This study analyzed fatty acid and stable isotope (δ13C and δ15N) composition of surface and bottom Particulate Organic Matter (s-POM and b-POM, respectively), Sedimentary Organic Matter (SOM) and sand dollar tissue along a near shore to offshore gradient during two contrasting seasons associated either with sharp or weak water column stratification (i.e. High\ vs\ Low Stratification Periods). Results revealed high relative abundances of polyunsaturated fatty acids (notably macro- and microalgae markers) in POM during the Low Stratification Period while the High Stratification Period was characterized by elevated relative abundance of saturated fatty acids indicating a higher organic matter degradation state. In addition, strong seasonal differences were also observed in food availability with four-fold higher concentrations in total suspended solids during Low\ vs\ High Stratification Periods. These results suggested thus multiple negative effects of stratification on pelagic-benthic coupling and POM quality. Lower nutrient repletion of surface waters during period of sharp stratification diminishes pelagic-benthic coupling by reducing food availability, POM quality and vertical transfer of organic matter. By contrast, the sediment-based diet of\ E. parma\ showed a low spatiotemporal variability reflecting the homogenous composition of the SOM. This study suggests that intensified water column stratification due to increasing sea surface temperatures may modify the pelagic-benthic coupling and future quality and composition of POM pools.}, issn = {00796611}, doi = {10.1016/j.pocean.2020.102483}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0079661120302184}, author = {Bridier, Guillaume and Tarik Meziane and Grall, Jacques and Chauvaud, Laurent and Donnet, S{\'e}bastien and Lazure, Pascal and Fr{\'e}d{\'e}ric Olivier} } @article {7202, title = {Anthropogenic boat noise reduces feeding success in winter flounder larvae (Pseudopleuronectes americanus)}, journal = {Environmental Biology of Fishes}, volume = {103}, year = {2020}, month = {Jan-09-2020}, pages = {1079 - 1090}, abstract = {The aim of this study was to explore an emerging discipline addressing the impact of anthropogenic noise on larval stages of marine organisms. We assessed the influence of boat noise on the feeding behaviour of the pelagic larvae of winter flounder (Pseudopleuronectes americanus, Walbaum, 1792). The hypothesis was that boat noise influences the feeding behaviour of P. americanus flounder larvae independently of prey\  density. Aquaria containing P. americanus larvae were placed in water baths in which boat noise was diffused for the {\textquotedblleft}noise{\textquotedblright} treatment and compared to control aquaria with no sound emissions. Larvae were filmed\  using cameras placed above the aquaria and their behaviour was recorded. Larvae exposed to anthropogenic noise displayed significantly fewer hunting events than controls, and their stomach volumes were\  significantly smaller. This noise effect was the same at all prey densities used, suggesting that larval feeding behaviour is negatively impaired by anthropogenic noise.}, keywords = {Feeding behaviour}, issn = {0378-1909}, doi = {10.1007/s10641-020-01005-3}, url = {http://link.springer.com/10.1007/s10641-020-01005-3}, author = {Gendron, Gilberte and Tremblay, Rejean and Jolivet, Aur{\'e}lie and Fr{\'e}d{\'e}ric Olivier and Chauvaud, Laurent and Winkler, Gesche and Audet, C{\'e}line} } @article {6866, title = {A current synthesis on the effects of electric and magnetic fields emitted by submarine power cables on invertebrates}, journal = {Marine Environmental Research}, volume = {159}, year = {2020}, pages = {104958}, abstract = {The goal of clean renewable energy production has promoted the large-scale deployment of marine renewable energy devices, and their associated submarine cable network. Power cables produce both electric and magnetic fields that raise environmental concerns as many marine organisms have magneto and electroreception abilities used for vital purposes. Magnetic and electric fields{\quotesinglbase}{\"A}{\^o} intensities decrease with distance away from the cable. Accordingly, the benthic and the sedimentary compartments are exposed to the highest field values. Although marine invertebrate species are the major fauna of these potentially exposed areas, they have so far received little attention. We provide extensive background knowledge on natural and anthropogenic marine sources of magnetic and electric fields. We then compile evidence for magneto- and electro-sensitivity in marine invertebrates and further highlight what is currently known about their interactions with artificial sources of magnetic and electric fields. Finally we discuss the main gaps and future challenges that require further investigation.}, issn = {0141-1136}, doi = {https://doi.org/10.1016/j.marenvres.2020.104958}, url = {http://www.sciencedirect.com/science/article/pii/S0141113619307706}, author = {Luana Albert and Fran{\c c}ois Deschamps and Aur{\'e}lie Jolivet and Fr{\'e}d{\'e}ric Olivier and Laurent Chauvaud and Sylvain Chauvaud} } @article {6578, title = {Influence of the physiological condition of bivalve recruits on their post-settlement dispersal potential}, journal = {Marine Ecology Progress Series}, volume = {636}, year = {2020}, pages = {77 - 89}, abstract = {Secondary dispersal (= migration) of bivalves occurs after metamorphosis and is a key recruitment process that can radically change patterns of primary settlement. An example of secondary dispersal is active migration behavior of bivalve recruits such as in bysso-pelagic drift. We hypothesize that these active migrations represent an energy cost for recruits and that the ability to actively migrate will depend upon the recruit{\textlnot}{\'\i}s physiological profile (quantity and quality of energy reserves). In lab experiments, we hatched 4 batches of recruits of\ Venus verrucosa\ with different physiological profiles by varying rearing temperature and diet composition. We then introduced these recruits into a fall velocity tube (5 m height) to estimate their vertical fall velocity as a proxy of their dispersal potential: slower fall velocity implies enhanced dispersal potential. We also compared alive vs. passive (dead) recruits to assess behavioral differences. Fall velocity increased logarithmically with recruit volume for each treatment, and no differences between active and passive individuals were observed for batches reared at 20{\textdegree}C with a mixture of\ Tisochrysis lutea\ and\ Chaetoceros gracilis. By contrast, active recruits in 2 other treatments (T. lutea\ at 20{\textdegree}C and a mix of\ C. gracilis\ and\ T. lutea\ at 15{\textdegree}C) significantly decreased their fall velocity regardless of their volume. Moreover, the ability of recruits to control their fall velocity by their behavior was correlated with triglyceride content. Recruits with the highest energy reserves had the greatest capacity to decrease their fall velocity, which suggests a major role of physiological conditions on potential secondary dispersal. We also used a benthic flume to test the substrate selection ability of recruits depending on their physiological profile and found no differences between physiologically different batches. However,\ V. verrucosa\ recruits preferred fine sediments, unlike adults, which live mainly in coarse sediment habitats; such difference in substrate preference suggests potential secondary migrations between nursery and adult areas.}, keywords = {Behavior, Bivalves recruits, Energetic reserves, Physiology, secondary migrations, Venus verrucosa}, issn = {0171-8630}, doi = {10.3354/meps13223}, url = {https://www.int-res.com/abstracts/meps/v636/p77-89}, author = {Martin For{\^e}t and Fr{\'e}d{\'e}ric Olivier and Miner, P and Gesche Winkler and Nadalini, J-B and R{\'e}jean Tremblay} } @article {7187, title = {Shells of the bivalve Astarte moerchi give new evidence of a strong pelagic-benthic coupling shift occurring since the late 1970s in the North Water polynya}, journal = {Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences}, volume = {378}, year = {2020}, month = {Feb-10-2020}, pages = {20190353}, abstract = {Climate changes in the Arctic may weaken the currently tight pelagic-benthic coupling. In response to decreasing sea ice cover, arctic marine systems are expected to shift from a {\textquoteleft}sea-ice algae{\textendash}benthos{\textquoteright} to a {\textquoteleft}phytoplankton-zooplankton{\textquoteright} dominance. We used mollusc shells as bioarchives and fatty acid trophic markers to estimate the effects of the reduction of sea ice cover on the food exported to the seafloor. Bathyal bivalve\ Astarte moerchi\ living at 600 m depth in northern Baffin Bay reveals a clear shift in growth variations and Ba/Ca ratios since the late 1970s, which we relate to a change in food availability. Tissue fatty acid compositions show that this species feeds mainly on microalgae exported from the euphotic zone to the seabed. We, therefore, suggest that changes in pelagic-benthic coupling are likely due either to local changes in sea ice dynamics, mediated through bottom-up regulation exerted by sea ice on phytoplankton production, or to a mismatch between phytoplankton bloom and zooplankton grazing due to phenological change. Both possibilities allow a more regular and increased transfer of food to the seabed.

This article is part of the theme issue {\textquoteleft}The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning{\textquoteright}.}, issn = {1364-503X}, doi = {10.1098/rsta.2019.0353}, url = {https://royalsocietypublishing.org/doi/10.1098/rsta.2019.0353}, author = {Fr{\'e}d{\'e}ric Olivier and Gaillard, Blandine and Thebault, Julien and Tarik Meziane and Tremblay, Rejean and Dumont, Dany and B{\'e}langer, Simon and Gosselin, Michel and Jolivet, Aur{\'e}lie and Chauvaud, Laurent and Martel, Andr{\'e} L. and Rysgaard, S{\o}ren and Olivier, Anne-H{\'e}l{\`e}ne and Pettr{\'e}, Julien and Mars, J{\'e}r{\^o}me and Gerber, Silvain and Archambault, Philippe} } @article {5830, title = {Coastal waters freshening and extreme seasonality affect organic matter sources, quality, and transfers in a High Arctic fjord (Young Sound, Greenland)}, journal = {Marine Ecology Progress Series}, volume = {610}, year = {2019}, pages = {15-31}, abstract = {

Arctic benthic ecosystems are expected to experience strong modifications in the dynamics of primary producers and/or benthic-pelagic coupling under climate change. However, lack of knowledge about the influence of physical constraints (e.g. ice-melting associated gradients) on organic matter sources, quality, and transfers in systems such as fjords can impede predictions of the evolution of benthic-pelagic coupling in response to global warming. Here, sources and quality of particulate organic matter (POM) and sedimentary organic matter (SOM) were characterized along an inner-outer gradient in a High Artic fjord (Young Sound, NE Greenland) exposed to extreme seasonal and physical constraints (ice-melting associated gradients). The influence of the seasonal variability of food sources on 2 dominant filter-feeding bivalves (Astarte moerchi and Mya truncata) was also investigated. Results revealed the critical impact of long sea ice/snow cover conditions prevailing in Young Sound corresponding to a period of extremely poor and degraded POM and SOM. Freshwater inputs had a very local impact during summer, with relatively more degraded POM at the surface compared to bottom waters that were less nutritionally depleted but more heterogeneous among the sampled stations. Terrestrial inputs contributed to the SOM composition but showed a large variability along the fjord. Finally, diet analyses underlined the contrasted nutritional conditions, showing much higher lipid reserves in A. moerchi than in M. truncata during winter. Under a scenario with increased freshwater input, such results suggest a decline in organic matter quality and production in Young Sound, with subsequent impacts on benthic food webs.

}, doi = {10.3354/meps12857}, url = {https://www.int-res.com/abstracts/meps/v610/p15-31/}, author = {Bridier, Guillaume and Tarik Meziane and Grall, Jacques and Laurent Chauvaud and Sejr, Mikael K. and Menneteau, Sylvain and Fr{\'e}d{\'e}ric Olivier} } @article {5315, title = {Cultured eastern oysters (Crassostrea virginica): retention and assimilation of picophytoplankton using a multi-biomarker approach}, journal = {Aquatic Living Resources}, volume = {30}, year = {2018}, month = {08/2018}, type = {Article}, abstract = {

{In this study, we investigated the food sources of eastern oysters Crassostrea virginica cultivated in Atlantic Canada. Stable isotopes (C-13 and N-15) and fatty acid biomarkers were used to identify these sources under in situ conditions for suspended (similar to 0.5 m below surface) and bottom(similar to 2 m) culture stocks. It was found that particulate organic matter represented the main food source, with major contributions from live phytoplankton. Higher lipid contents were detected in the digestive glands of suspended oysters compared to bottom oysters (p \< 0.05). Bottom oysters did not show significant preference for detrital or bacterial organic matter. Near-surface waters contained an elevated picophytoplankton biomass (PPP, 0.2-2 mu m, 1.93 +/- 0.16mg l(-1), mean +/- SEM) compared to nanophytoplankton biomass (NPP, \> 2 mu m, 1.05 +/- 0.15 mu g l(-1), mean +/- SEM). To determine whether the small size PPP was captured and assimilated by C. virginica, feeding trials were conducted in the laboratory using three PPP/NPP diets (20\%, 50\%, and 80\% PPP), consisting of isotopically-labelled (delta C-13) PPP cells (Nannochloropsis oculata) and non-labelled NPP cells (Tisochrysis lutea). An isotopically-labelled fatty acids analysis indicated PPP assimilation in various tissues (digestive gland, gills, mantle, and abductor muscle), including from oysters fed the reduced (20\%) PPP diet. Isotopic enrichment (C-13) in the FA 22:2 (non-methylene-interrupted or NMI) showed that precursors of NMIs utilized PPP carbon in its biosynthesis process. In conclusion, C. virginica assimilated primarily particulate organic matter (POM), including PPP, which dominated the phytoplankton community in near surface waters. C. virginica can exploit PPP carbon during fatty acid production and further biosynthesis.}

}, keywords = {Aquaculture, fatty acids, Picophytoplankton, Shellfish}, Stable isotopes, {Crassostrea virginica}, issn = {{0990-7440}}, doi = {{10.1051/alr/2017031}}, author = {R{\'e}mi Sonier and R{\'e}jean Tremblay and Fr{\'e}d{\'e}ric Olivier and Tarik Meziane and Comeau, Luc Andre} } @article {5559, title = {Effect of sediment, salinity, and velocity on the behavior of juvenile winter flounder (Pseudopleuronectes americanus)}, journal = {Environmental Biology of Fishes}, year = {2018}, month = {07/2018}, pages = {1-10}, abstract = {

Winter flounder (Pseudopleuronectes americanus) is a benthic flatfish that is economically important for recreational and commercial fishing in North America. In the last twenty years, the species has undergone a drastic decline, mainly due to anthropic influence. The goal of this study was to gain knowledge on habitat preferences and behavior of juvenile winter flounder to improve the management of natural stocks and optimize release sites of juveniles produced for stock enhancement. Three abiotic factors (sediment, current, and salinity) potentially influencing the distribution of flatfish species were tested in a recircurlating flume with juvenile winter flounder. Time budgets of observed behaviors including swimming, orientation, and burying capacity were analyzed. Sediment texture was the only factor that significantly influenced the burying behavior of winter flounder juveniles; shear velocity, salinity, and sediment had no effect on the orientation of juveniles.

}, keywords = {Current, salinity, Sediment, Swimming behavior, Winter flounder}, issn = {0378-1909}, doi = {https://doi.org/10.1007/s10641-018-0793-4}, url = {https://link.springer.com/article/10.1007\%2Fs10641-018-0793-4}, author = {Provencher, T and Fr{\'e}d{\'e}ric Olivier and Audet, C and R{\'e}jean Tremblay} } @article {5607, title = {Temporal variation of secondary migrations potential: concept of temporal windows in four commercial bivalve species}, journal = {Aquatic Living Resources}, volume = {31}, year = {2018}, month = {08/2018}, pages = {1-9}, abstract = {

Post-settlement dispersal potential of four commercial bivalve species (Mytilus edulis, Pecten maximus, Venus verrucosa and Ruditapes philippinarum) were studied through the assessment of recruits{\textquoteright} sinking velocities by using a sinking velocity tube of five meters height. In parallel, dynamics of shear stress were monitored for five months on a tidal habitat characterized by the presence and the dispersal of the four species. By coupling both datasets we propose first theoretical estimates of temporal windows of secondary migrations. These experiments revealed interspecific differences in migration potential relate to shell shapes and behaviour, especially to secretion of byssal threads. The sensitivity to passive and active post-settlement migrations seems to rely on the\ synchronisation between the arrival on the sediment, the tidal regime (spring tide, neap tide), but also the rate of growth of the recruits. The present study confirms that patterns of secondary migrations of bivalve recruits result from a close physical-biological coupling involving benthic boundary layer (BBL) hydrodynamics and shell morphology as well as eco-ethological responses to environmental conditions but clearly modulated by the growth dynamics until a threshold size when drifting is no longer possible.

}, keywords = {Bivalves recruits, drifting, secondary migrations, temporal windows}, doi = { https://doi.org/10.1051/alr/2018007 }, url = {https://www.alr-journal.org/articles/alr/abs/2018/01/alr170158/alr170158.html}, author = {Martin For{\^e}t and R{\'e}jean Tremblay and Urs Neumeier and Fr{\'e}d{\'e}ric Olivier} } @article {5210, title = {Cultured eastern oysters (Crassostrea virginica): retention and assimilation of picophytoplankton using a multi-biomarker approach}, journal = {Aquatic Living Ressources}, volume = {30}, year = {2017}, month = {08/2017}, pages = {1-13}, doi = {doi.org/10.1051/alr/2017031}, url = {https://www.alr-journal.org/articles/alr/abs/2017/01/alr170056/alr170056.html}, author = {R{\'e}mi Sonier and R{\'e}jean Tremblay and Fr{\'e}d{\'e}ric Olivier and Tarik Meziane and Comeau, L. A.} } @article {4801, title = {Dietary plasticity in the bivalve Astarte moerchi revealed by a multimarker study in two Arctic fjords}, journal = {Marine Ecology Progress Series}, volume = {567}, year = {2017}, pages = {157-172}, abstract = {

ABSTRACT: Arctic coastal ecosystems are likely to be strongly affected by predicted environmental changes such as sea-ice decline and increase in freshwater input and turbidity. These changes are expected to impact primary production dynamics and consequently benthic consumers. The trophic relationship between primary producers and benthic primary consumers were compared in 2 Arctic fjords with different seasonal ice-cover: Young Sound (NE Greenland, a high-Arctic fjord) and Kongsfjorden (Svalbard Archipelago, a sub-Arctic fjord). For comparison, we selected the filter-feeding bivalve Astarte moerchi (belonging to the complex A. borealis), which has a broad geographical distribution in the Arctic. The bivalve digestive glands and food sources were characterized with fatty acids (FAs), bulk stable isotopes, and compound-specific stable isotopes of individual FAs. Our results suggest that diatoms of pelagic and/or benthic origin are the main contributors to the A. moerchi diet in Young Sound and make up a less important fraction of the diet in the Kongsfjorden population. A contribution by sympagic diatoms is clearly excluded in the sub-Arctic fjord and needs to be further assessed in the Arctic fjord. The A. moerchi diet in sub-Arctic Kongsfjorden is more diversified, varies with season, and has contributions from dinoflagellates and macroalgal detritus. These results, together with higher concentrations of total FAs in the Young Sound population, demonstrated and characterized the trophic plasticity of this bivalve species. Based on these results, we discuss potential effects of environmental factors (shifts in trophic resources, increase in turbidity) for A. moerchi populations in changing Arctic ecosystems.

}, author = {De Cesare, S and Tarik Meziane and Laurent Chauvaud and Richard, J and Sejr, M K and Th{\'e}bault, J and Winkler, G and Fr{\'e}d{\'e}ric Olivier} } @article {4800, title = {Food resources of the bivalve Astarte elliptica in a sub-Arctic fjord: a multi-biomarker approach}, journal = {Marine Ecology Progress Series}, volume = {567}, year = {2017}, pages = {139-156}, abstract = {

ABSTRACT: It is generally agreed that pelagic-benthic coupling is tight on Arctic shelves, i.e. that organic matter produced in the surface layers supports the seafloor and benthos. However, this paradigm is mainly based on the assumption that phytoplankton and ice algae are the main sources of carbon for the benthic communities. Climate change is expected to alter the relative contribution of food sources for benthic organisms. Macroalgal biomass is predicted to increase in near-shore systems in response to increased temperature and reduced sea ice cover. Thus, a better understanding of the relative contribution of benthic and pelagic components in benthic food webs in the Arctic is needed. In this study, a multi-biomarker approach (stable isotopes, fatty acid trophic markers, and compound-specific stable isotope analysis) was applied to link potential sources of carbon, including particulate organic matter from subsurface and bottom waters, sediment organic matter, and 6 macroalgal species to the diet of the bivalve Astarte elliptica collected below the euphotic zone in a sub-Arctic fjord (Kobbefjord, Greenland). Results showed that A. elliptica feeds on particulate and sediment organic matter and that brown macroalgae significantly support the Arctic benthic food web. Multi-biomarker approaches can be used to determine the diet of benthic organisms and track temporal variability in sources of food. It therefore appears to be an interesting method to study food regime strategies in response to changing primary production dynamics.

}, author = {Gaillard, B and Tarik Meziane and R{\'e}jean Tremblay and P Archambault and Blicher, M E and Laurent Chauvaud and Rysgaard, S and Fr{\'e}d{\'e}ric Olivier} } @article {4725, title = {Nursery function of coastal temperate benthic habitats: New insight from the bivalve recruitment perspective}, journal = {Journal of Sea Research}, volume = {121}, year = {2017}, pages = {11-23}, abstract = {


Marine habitat function has been typically investigated in terms of biogeochemical regulation but rarely in terms of population renewal, which is mainly controlled by recruitment dynamics. The recruitment phase is crucial for
organisms with a bentho-pelagic life cycle, such as bivalves, and it regulates the population renewal success. This study provides new insight on the role of temperate benthic habitats on bivalve recruitment, as a function of
nursery areas. Six dominant benthic habitats of the Chausey archipelago (Normandy, France) were studied. In each habitat, bivalve recruit assemblages were described at the end of two reproductive seasons. Furthermore, Ostrea edulis
juveniles were immerged on each habitat during two months to compare growth performances and feeding status, estimated by fatty acid composition. Recruit assemblages differ from each habitat according to sediment grain-size composition and bathymetrical levels. Subtidal habitats, and especially Crepidula fornicata banks and Glycymeris glycymeris coarse sands, supported the highest species abundance and richness of recruits. All O. edulis juveniles fed on the same trophic resources but digestive glands of juveniles from C. fornicata banks were more concentrated in total fatty acids than those from subtidal G. glycymeris coarse sands and maerl banks. Our results depict the key role of subtidal and structured habitats, composed of ecosystem engineers, in enhancing bivalve recruitment and extending the bivalve population renewal. This study suggests that the crucial role of
these habitats as bivalve nurseries must be integrated in management perspectives

}, author = {Pierrick Barbier and Tarik Meziane and For{\^e}t, M and R{\'e}jean Tremblay and Robert, R and Fr{\'e}d{\'e}ric Olivier} } @article {5366, title = {Regional and latitudinal patterns of soft-bottom macrobenthic invertebrates along French coasts: Results from the RESOMAR database}, journal = {Journal of Sea Research}, volume = {130}, year = {2017}, pages = {96 - 106}, abstract = {

This study aims to describe the patterns of soft bottom macrozoobenthic richness along French coasts. It is based on a collaborative database developed by the {\textquotedblleft}R{\'e}seau des Stations et Observatoires Marins{\textquotedblright} (RESOMAR). We investigated patterns of species richness in sublittoral soft bottom habitats (EUNIS level 3) at two different spatial scales: 1) seaboards: English Channel, Bay of Biscay and Mediterranean Sea and 2) 0.5{\textdegree} latitudinal and longitudinal grid. Total observed richness, rarefaction curves and three incidence-based richness estimators (Chao2, ICE and Jacknife1) were used to compare soft bottom habitats species richness in each seaboard. Overall, the Mediterranean Sea has the highest richness and despite higher sampling effort, the English Channel hosts the lowest number of species. The distribution of species occurrence within and between seaboards was assessed for each major phylum using constrained rarefaction curves. The Mediterranean Sea hosts the highest number of exclusive species. In pairwise comparisons, it also shares a lower proportion of taxa with the Bay of Biscay (34.1\%) or the English Channel (27.6\%) than that shared between these two seaboards (49.7\%). Latitudinal species richness patterns along the Atlantic and English Channel coasts were investigated for each major phylum using partial LOESS regression controlling for sampling effort. This showed the existence of a bell-shaped latitudinal pattern, highlighting Brittany as a hotspot for macrobenthic richness at the confluence of two biogeographic provinces.

}, keywords = {France, Latitudinal pattern, Regional pattern, Soft-bottom, Species richness, Zoobenthos}, issn = {1385-1101}, doi = {https://doi.org/10.1016/j.seares.2017.03.011}, url = {http://www.sciencedirect.com/science/article/pii/S1385110116302660}, author = {R{\'e}gis K. Gallon and Nicolas Lavesque and Jacques Grall and C{\'e}line Labrune and Antoine Gr{\'e}mare and Guy Bachelet and Hugues Blanchet and Paulo Bonif{\'a}cio and Vincent M.P. Bouchet and Jean-Claude Dauvin and Nicolas Desroy and Franck Gentil and Laurent Guerin and C{\'e}line Houbin and J{\'e}r{\^o}me Jourde and Sandrine Laurand and Michel Le Duff and Vincent Le Garrec and Xavier de Montaudouin and Fr{\'e}d{\'e}ric Olivier and Francis Orvain and Pierre-Guy Sauriau and Eric Thi{\'e}baut and Olivier Gauthier} } @article {4269, title = {Influence of intertidal recreational fisheries and {\textquoteleft}bouchot{\textquoteright} mussel culture on bivalve recruitment}, journal = {Marine Environmental Research}, volume = {117}, year = {2016}, pages = {1 - 12}, abstract = {

Abstract In coastal environments, fishing and aquaculture may be important sources of disturbance to ecosystem functioning, the quantification of which must be assessed to make them more sustainable. In the Chausey Archipelago, France, recreational fishing and commercial shellfish farming are the only two evident anthropogenic activities, dominated by bivalve hand-raking and {\textquoteleft}bouchot{\textquoteright} mussel culture, respectively. This study evaluates the impact of both activities on bivalve recruitment dynamics by comparing primary recruitment intensity (short-term effect) and recruitment efficiency (medium-term effect) by sampling bivalves in reference (undisturbed) and disturbed (i.e. subjected to hand-raking or in {\textquoteleft}bouchot{\textquoteright} mussel culture areas) parcels throughout and at the end of the recruitment season, respectively. Specific hypotheses evaluated were that (H1) bivalve hand-raking negatively affects bivalve recruitment and that (H2) {\textquoteleft}bouchot{\textquoteright} mussel culture promotes bivalve recruitment. Patterns in bivalve community structure in reference parcels (i.e. natural pattern) differed between initial and final recruitment, underlining the great importance of early post-settlement processes, particularly secondary dispersal. Primary recruitment intensity was inhibited in hand-raking parcels whereas it was promoted in {\textquoteleft}bouchot{\textquoteright} mussel culture parcels, but the effect on recruitment efficiency was muted for both activities due to post-settlement processes. Nevertheless, the importance of effects that occur during the first step of recruitment should not be ignored as they may affect bivalve communities and induce immediate consequences on the trophic web through a cascade effect. Finally, it is highlighted that hand-raking damages all life stages of the common cockle Cerastoderma edule, one of the major target species, suggesting that this activity should be managed with greater caution than is currently done.

}, keywords = {{\textquoteleft}Bouchot{\textquoteright}}, issn = {0141-1136}, doi = {http://dx.doi.org/10.1016/j.marenvres.2016.03.006}, url = {http://www.sciencedirect.com/science/article/pii/S0141113616300319}, author = {Nicolas Toupoint and Pierrick Barbier and R{\'e}jean Tremblay and P Archambault and Christopher W. McKindsey and Gesche Winkler and Tarik Meziane and Fr{\'e}d{\'e}ric Olivier} } @article {4676, title = {A new species and four new records of sedentary polychaetes from the Canadian High Arctic}, journal = {Journal of the Marine Biological Association of the United Kingdom}, year = {2016}, month = {007}, pages = {1-10}, abstract = {

During ArcticNet surveys aboard {\textquoteleft}CCGS Amundsen{\textquoteright} in 2011, several subtidal stations located in Canadian Archipelago were sampled in order to study the composition of their benthic communities. Among the abundant material sampled, several specimens of rare polychaete species were found. Examination of this material showed four species not previously recorded in the area, and a new species described herein. Descriptions of these specimens are given in this work. Ophelina brattegardi Kongsrud et al., 2011 is characterized by a body composed of 27{\textendash}28 chaetigers, by having the parapodia of the last four chaetigers shifted to the ventral side of the body, and by lacking branchiae in mid-body chaetigers. Macrochaeta polyonix Eliason, 1962 is unique within the genus in having several (instead of one or two) compound neurochaetae in anterior parapodia. Chaetozone acuta Banse \& Hobson, 1968 is characterized by having spines from anterior third of the body and arranged in bundles composed of " $\#$ "just a few chaetae. Chaetozone jubata Chambers \& Woodham, 2003 can be distinguished from similar species by having very long capillary chaetae from chaetiger 2 or 3. Finally, Dialychone hervyae n. sp. is characterized by bearing four pairs of radioles with narrow flanges, by the bilobed tip of its first peristomial ring that projects beyond the collar, and by the paleate thoracic notochaetae bearing long mucros.

}, doi = {10.1017/S0025315416000953}, url = {https://www.cambridge.org/core/article/div-class-title-a-new-species-and-four-new-records-of-sedentary-polychaetes-from-the-canadian-high-arctic-div/3950848DE7205A141D2159F4FA91FDA2}, author = {Eduardo Lopez and Fr{\'e}d{\'e}ric Olivier and Cindy Grant and P Archambault} } @article {4261, title = {Picophytoplankton contribution to Mytilus edulis growth in an intensive culture environment}, journal = {Marine Biology}, volume = {163}, year = {2016}, pages = {1{\textendash}15}, issn = {1432-1793}, doi = {10.1007/s00227-016-2845-7}, url = {http://dx.doi.org/10.1007/s00227-016-2845-7}, author = {R{\'e}mi Sonier and Filgueira, R. and Guyondet, T. and R{\'e}jean Tremblay and Fr{\'e}d{\'e}ric Olivier and Tarik Meziane and Starr, M. and LeBlanc, A. R. and Comeau, L. A.} } @article {4260, title = {Spatial and temporal dynamics of nano- and pico-size particulate organic matter (POM) in a coastal megatidal marine system}, journal = {Limnology and Oceanography}, volume = {61}, year = {2016}, month = {05/2016}, pages = {1087-1100}, abstract = {

Surface water samples of size-selected seston (0.7{\textendash}20 μm) were collected from April 2013 to September 2013 at three similar coarse-sand benthic habitats. Additionally, seston sampling was performed at a fixed location throughout a complete tidal cycle (2014). A combination of fatty acid (FA), isotope, and flow cytometry analyses were used to determine the quality and quantity of nano- and pico-sized particulate organic matter (POM). High variability was found between fatty acid replicate samples. Similar temporal patterns were observed at two sheltered sites, while the exposed site displayed less pronounced seasonal changes. Lower concentrations of 16C and 18C polyunsaturated fatty acids were found during low tide sampling. Globally, POM was dominated by picoeukaryotes, with concentrations exceeding 50,000 cells mL-1, and (16:4ω3 + 18:3ω3)/Σω3 is proposed as novel biomarker of picoeukaryotes in this region.

}, issn = {1939-5590}, doi = {10.1002/lno.10276}, url = {http://dx.doi.org/10.1002/lno.10276}, author = {Moynihan, Molly A. and Pierrick Barbier and Fr{\'e}d{\'e}ric Olivier and Nicolas Toupoint and Tarik Meziane} } @article {4519, title = {Validation of trophic and anthropic underwater noise as settlement trigger in blue mussels}, journal = {Scientific Reports}, volume = {6}, year = {2016}, pages = {33829}, author = {Jolivet, Aur{\'e}lie and R{\'e}jean Tremblay and Fr{\'e}d{\'e}ric Olivier and Gervaise, C{\'e}dric and R{\'e}mi Sonier and Genard, Bertrand and Laurent Chauvaud} } @article {3982, title = {Dietary tracers in Bathyarca glacialis from contrasting trophic regions in the Canadian Arctic}, journal = {Marine Ecology Progress Series}, volume = {536}, year = {2015}, month = {09/2015}, pages = {175-186}, keywords = {Bathyarca glacialis, Bivalve, Canadian Arctic Archipelago, FATMs, Fatty acid trophic markers, Non-methylene-interrupted fatty acid, Pelagic {\textendash} benthic coupling}, author = {Gaillard, B and Tarik Meziane and R{\'e}jean Tremblay and P Archambault and Layton, KKS and Martel, AL and Fr{\'e}d{\'e}ric Olivier} } @article {3487, title = {Multiscale patterns in the diversity and organization of benthic intertidal fauna among French Atlantic estuaries}, journal = {Journal of Sea Research}, volume = {90}, year = {2014}, month = {07/2014}, pages = {95 - 110}, abstract = {

Based on a parallel sampling conducted during autumn 2008, a comparative study of the intertidal benthic macrofauna among 10 estuarine systems located along the Channel and Atlantic coasts of France was performed in order to assess the level of fauna similarity among these sites and to identify possible environmental factors involved in the observed pattern at both large (among sites) and smaller (benthic assemblages) scales. More precisely this study focused on unraveling the observed pattern of intertidal benthic fauna composition and diversity observed at among-site scale by exploring both biotic and abiotic factors acting at the among- and within-site scales. Results showed a limited level of similarity at the among-site level in terms of intertidal benthic fauna composition and diversity. The observed pattern did not fit with existing transitional water classification methods based on fish or benthic assemblages developed in the frame of the European Water Framework Directive (WFD). More particularly, the coastal plain estuaries displayed higher among-site similarity compared to ria systems. These coastal plain estuaries were characterized by higher influence of river discharge, lower communication with the ocean and high suspended particulate matter levels. On the other hand, the ria-type systems were more dissimilar and different from the coastal plain estuaries. The level of similarity among estuaries was mainly linked to the relative extent of the intertidal {\textquotedblleft}Scrobicularia plana{\textendash}Cerastoderma edule{\textquotedblright} and {\textquotedblleft}Tellina tenuis{\textquotedblright} or {\textquotedblleft}Venus{\textquotedblright} communities as a possible consequence of salinity regime, suspended matter concentrations and fine particles supply with consequences on the trophic functioning, structure and organization of benthic fauna. Despite biogeographical patterns, the results also suggest that, in the context of the WFD, these estuaries should only be compared on the basis of the most common intertidal habitat occurring throughout all estuarine systems and that the \{EUNIS\} biotope classification might be used for this purpose. In addition, an original inverse relation between γ-diversity and area was shown; however, its relevance might be questioned.

}, keywords = {Diversity, Estuaries, Macrozoobenthos, Structuring Factors, WFD}, issn = {1385-1101}, doi = {http://dx.doi.org/10.1016/j.seares.2014.02.014}, url = {http://www.sciencedirect.com/science/article/pii/S1385110114000495}, author = {Hugues Blanchet and Beno{\^\i}t Gouillieux and Sandrine Alizier and Jean-Michel Amouroux and Guy Bachelet and Anne-Laure Barill{\'e} and Jean-Claude Dauvin and Xavier de Montaudouin and Val{\'e}rie Derolez and Nicolas Desroy and Jacques Grall and Antoine Gr{\'e}mare and Pascal Hacquebart and J{\'e}r{\^o}me Jourde and C{\'e}line Labrune and Nicolas Lavesque and Antoine Meirland and Thiebaut Nebout and Fr{\'e}d{\'e}ric Olivier and Corine Pelaprat and Thierry Ruellet and Pierre-Guy Sauriau and S{\'e}bastien Thorin} } @article {Passarelli2013, title = {{Organisms as cooperative ecosystem engineers in intertidal flats}}, journal = {Journal of Sea Research}, volume = {92}, year = {2014}, month = {09/2014}, pages = {92-101}, abstract = {

The importance of facilitative interactions and organismal ecosystem engineering for establishing the structure of communities is increasingly being recognised for many different ecosystems. For example, soft-bottom tidal flats host a wide range of ecosystem engineers, probably because the harsh physico-chemical environmental conditions render these species of particular importance for community structure and function. These environments are therefore interesting when focusing on how ecosystem engineers interact and the consequences of these interactions on community dynamics. In this review, we initially detail the influence on benthic systems of two kinds of ecosystem engineers that are particularly common in tidal flats. Firstly, we examine species providing biogenic structures, which are often the only source of habitat complexity in these environments. Secondly, we focus on species whose activities alter sediment stability, which is a crucial feature structuring the dynamics of communities in tidal flats. The impacts of these engineers on both environment and communities were assessed but in addition the interaction between ecosystem engineers was examined. Habitat cascades occur when one engineer favours the development of another, which in turn creates or modifies and improves habitat for other species. Non-hierarchical interactions have often been shown to display non-additive effects, so that the effects of the association cannot be predicted from the effects of individual organisms. Here we propose the term of {\textquotedblleft}cooperative ecosystem engineering{\textquotedblright} when two species interact in a way which enhances habitat suitability as a result of a combined engineering effect. Finally, we conclude by describing the potential threats for ecosystem engineers in intertidal areas, potential effects on their interactions and their influence on communities and ecosystem function.

}, keywords = {Biogenic Structure, Cooperative Ecosystem Engineers, Habitat Cascade, Sediment stability, tidal flats}, doi = {10.1016/j.seares.2013.07.010}, author = {Passarelli, C and Fr{\'e}d{\'e}ric Olivier and Paterson, D M and Tarik Meziane and C{\'e}dric Hubas} } @article {3488, title = {Veliger Size at Metamorphosis and Temporal Variability in Prodissoconch II Morphometry in the Blue Mussel (Mytilus edulis): Potential Impact on Recruitment}, journal = {Journal of Shellfish Research}, volume = {33}, year = {2014}, month = {08/2014}, pages = {443-455}, abstract = {

Examination of the larval shell (prodissoconch) of molluscs with planktotrophic development can provide valuable information on their planktonic and early benthic life. We examined temporal variability of abundance and size among 11,994 veligers of the blue mussel (Mytilus edulis) in a coastal lagoon during settling periods between 1995 and 2009. Size and date at metamorphosis during the recruitment season were determined for 1,925 postlarvae (shell length, 255{\textendash}900 {\textmu}m) with prodissoconch II (PII) measurements. Emphasizing the recurrence of metamorphosis delay in the field, our study reveals a net increase in mean size at metamorphosis through time, with means for PII size ranging from 255{\textendash}288 {\textmu}m early in summer (after peak spawning events) to 400{\textendash}422 {\textmu}m (PII) during late July to early September. By estimating the {\textquotedblleft}true{\textquotedblright} settlement date using the amount of dissoconch secreted after metamorphosis, such time-series analyses appropriately recapitulated the temporal pattern of mean pediveliger (competent larvae) size in the plankton. Our results demonstrate that greater settlement success rates were related to small size at metamorphosis{\textemdash}in particular, less than 320 {\textmu}m. Seasonal increase in mean PII size occurring during the latter part of the settling period may be explained by competent veligers remaining adrift and delayed metamorphosis as a result of the lack of favorable encounters with a suitable substrate or the absence of specific trophic signals, or cues, required for stimulating settlement, thus forcing larvae to continue planktonic growth. The difference between the smallest and largest means for PII size corresponds to 122 {\textmu}m of larval shell growth, or 47.8\%, potentially representing a 322\% difference in larval body mass at settlement.

}, keywords = {blue mussel, delayed metamorphosis, larval settlement, Mytilus edulis, prodissoconch II, recruitment, veligers}, doi = {http://dx.doi.org/10.2983/035.033.0213}, url = {http://www.bioone.org/doi/full/10.2983/035.033.0213}, author = {Martel, Andr{\'e} L. and R{\'e}jean Tremblay and Nicolas Toupoint and Fr{\'e}d{\'e}ric Olivier and Myrand, B} } @article {7340, title = {Trophic resources of the bivalve, Venus verrucosa , in the Chausey archipelago (Normandy, France) determined by stable isotopes and fatty acids}, journal = {Aquatic Living Resources}, volume = {26}, year = {2013}, month = {Jan-01-2013}, pages = {229 - 239}, issn = {0990-7440}, doi = {10.1051/alr/2013058}, url = {http://www.alr-journal.org/10.1051/alr/2013058}, author = {Perez, V{\'e}ronique and Fr{\'e}d{\'e}ric Olivier and Tremblay, Rejean and Neumeier, Urs and Thebault, Julien and Chauvaud, Laurent and Tarik Meziane} }