%0 Journal Article %J Marine Ecology Progress Series %D 2020 %T Influence of the physiological condition of bivalve recruits on their post-settlement dispersal potential %A Martin Forêt %A Frédéric Olivier %A Miner, P %A Gesche Winkler %A Nadalini, J-B %A Réjean Tremblay %K Behavior %K Bivalves recruits %K Energetic reserves %K Physiology %K secondary migrations %K Venus verrucosa %X 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¬ís 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°C with a mixture of Tisochrysis lutea and Chaetoceros gracilis. By contrast, active recruits in 2 other treatments (T. lutea at 20°C and a mix of C. gracilis and T. lutea at 15°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. %B Marine Ecology Progress Series %V 636 %P 77 - 89 %G eng %U https://www.int-res.com/abstracts/meps/v636/p77-89 %! Mar. Ecol. Prog. Ser. %R 10.3354/meps13223 %0 Journal Article %J Aquatic Living Resources %D 2018 %T Cultured eastern oysters (Crassostrea virginica): retention and assimilation of picophytoplankton using a multi-biomarker approach %A Rémi Sonier %A Réjean Tremblay %A Frédéric Olivier %A Tarik Meziane %A Comeau, Luc Andre %K Aquaculture %K fatty acids %K Picophytoplankton %K Shellfish} %K Stable isotopes %K {Crassostrea virginica %X

{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.}

%B Aquatic Living Resources %V 30 %8 08/2018 %G eng %9 Article %R {10.1051/alr/2017031} %0 Journal Article %J Environmental Biology of Fishes %D 2018 %T Effect of sediment, salinity, and velocity on the behavior of juvenile winter flounder (Pseudopleuronectes americanus) %A Provencher, T %A Frédéric Olivier %A Audet, C %A Réjean Tremblay %K Current %K salinity %K Sediment %K Swimming behavior %K Winter flounder %X

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.

%B Environmental Biology of Fishes %P 1-10 %8 07/2018 %G eng %U https://link.springer.com/article/10.1007%2Fs10641-018-0793-4 %R https://doi.org/10.1007/s10641-018-0793-4 %0 Journal Article %J Aquatic Living Resources %D 2018 %T Temporal variation of secondary migrations potential: concept of temporal windows in four commercial bivalve species %A Martin Forêt %A Réjean Tremblay %A Urs Neumeier %A Frédéric Olivier %K Bivalves recruits %K drifting %K secondary migrations %K temporal windows %X

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' 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.

%B Aquatic Living Resources %V 31 %P 1-9 %8 08/2018 %G eng %U https://www.alr-journal.org/articles/alr/abs/2018/01/alr170158/alr170158.html %N 19 %R https://doi.org/10.1051/alr/2018007 %0 Journal Article %J Aquatic Living Ressources %D 2017 %T Cultured eastern oysters (Crassostrea virginica): retention and assimilation of picophytoplankton using a multi-biomarker approach %A Rémi Sonier %A Réjean Tremblay %A Frédéric Olivier %A Tarik Meziane %A Comeau, L. A. %B Aquatic Living Ressources %V 30 %P 1-13 %8 08/2017 %G eng %U https://www.alr-journal.org/articles/alr/abs/2017/01/alr170056/alr170056.html %R doi.org/10.1051/alr/2017031 %0 Journal Article %J Marine Ecology Progress Series %D 2017 %T Food resources of the bivalve Astarte elliptica in a sub-Arctic fjord: a multi-biomarker approach %A Gaillard, B %A Tarik Meziane %A Réjean Tremblay %A P Archambault %A Blicher, M E %A Laurent Chauvaud %A Rysgaard, S %A Frédéric Olivier %X

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.

%B Marine Ecology Progress Series %V 567 %P 139-156 %G eng %0 Journal Article %J Journal of Sea Research %D 2017 %T Nursery function of coastal temperate benthic habitats: New insight from the bivalve recruitment perspective %A Pierrick Barbier %A Tarik Meziane %A Forêt, M %A Réjean Tremblay %A Robert, R %A Frédéric Olivier %X


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

%B Journal of Sea Research %V 121 %P 11-23 %G eng %0 Journal Article %J Marine Environmental Research %D 2016 %T Influence of intertidal recreational fisheries and ‘bouchot’ mussel culture on bivalve recruitment %A Nicolas Toupoint %A Pierrick Barbier %A Réjean Tremblay %A P Archambault %A Christopher W. McKindsey %A Gesche Winkler %A Tarik Meziane %A Frédéric Olivier %K ‘Bouchot’ %X

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 ‘bouchot’ 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 ‘bouchot’ 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) ‘bouchot’ 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 ‘bouchot’ 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.

%B Marine Environmental Research %V 117 %P 1 - 12 %G eng %U http://www.sciencedirect.com/science/article/pii/S0141113616300319 %R http://dx.doi.org/10.1016/j.marenvres.2016.03.006 %0 Journal Article %J Marine Biology %D 2016 %T Picophytoplankton contribution to Mytilus edulis growth in an intensive culture environment %A Rémi Sonier %A Filgueira, R. %A Guyondet, T. %A Réjean Tremblay %A Frédéric Olivier %A Tarik Meziane %A Starr, M. %A LeBlanc, A. R. %A Comeau, L. A. %B Marine Biology %V 163 %P 1–15 %G eng %U http://dx.doi.org/10.1007/s00227-016-2845-7 %R 10.1007/s00227-016-2845-7 %0 Journal Article %J Scientific Reports %D 2016 %T Validation of trophic and anthropic underwater noise as settlement trigger in blue mussels %A Jolivet, Aurélie %A Réjean Tremblay %A Frédéric Olivier %A Gervaise, Cédric %A Rémi Sonier %A Genard, Bertrand %A Laurent Chauvaud %B Scientific Reports %V 6 %P 33829 %G eng %0 Journal Article %J Marine Ecology Progress Series %D 2015 %T Dietary tracers in Bathyarca glacialis from contrasting trophic regions in the Canadian Arctic %A Gaillard, B %A Tarik Meziane %A Réjean Tremblay %A P Archambault %A Layton, KKS %A Martel, AL %A Frédéric Olivier %K Bathyarca glacialis %K Bivalve %K Canadian Arctic Archipelago %K FATMs %K Fatty acid trophic markers %K Non-methylene-interrupted fatty acid %K Pelagic – benthic coupling %B Marine Ecology Progress Series %V 536 %P 175-186 %8 09/2015 %G eng %0 Journal Article %J Journal of Shellfish Research %D 2014 %T Veliger Size at Metamorphosis and Temporal Variability in Prodissoconch II Morphometry in the Blue Mussel (Mytilus edulis): Potential Impact on Recruitment %A Martel, André L. %A Réjean Tremblay %A Nicolas Toupoint %A Frédéric Olivier %A Myrand, B %K blue mussel %K delayed metamorphosis %K larval settlement %K Mytilus edulis %K prodissoconch II %K recruitment %K veligers %X

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, 255–900 µm) 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 255–288 µm early in summer (after peak spawning events) to 400–422 µm (PII) during late July to early September. By estimating the “true” 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—in particular, less than 320 µm. 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 µm of larval shell growth, or 47.8%, potentially representing a 322% difference in larval body mass at settlement.

%B Journal of Shellfish Research %V 33 %P 443-455 %8 08/2014 %G eng %U http://www.bioone.org/doi/full/10.2983/035.033.0213 %N 2 %R http://dx.doi.org/10.2983/035.033.0213