@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 {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 {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} }