Remi Sonier

Fisheries and Oceans Canada | DFO · Division of Science

Ecological carrying capacity (ECC) indices for bivalve culture rely on key ecosystem turnover rates: 1. clearance time (CT), the time needed for the cultured bivalves to filter the entire bay volume; 2. renewal time (RT), the time required to replace the entire bay volume with external water; and 3. production time (PT), the time needed for phytopl...

Eelgrass is designated as an ecologically significant species in the southern Gulf of St. Lawrence (sGSL). It is suspected that eelgrass in this region is currently experiencing population change in many places. One potential driver of eelgrass declines in the sGSL is suspended shellfish aquaculture. However, interactions between cultured shellfish...

Soft-shell clams, Mya arenaria, are fished commercially and recreationally across much of their distribution. Several management measures have been implemented in Atlantic Canada to regulate the clam fishery, including a minimum legal size limit of 50 mm. This legal size limit, however, is not based on contemporary data. A regional understanding...

The soft-shell clam, Mya arenaria, is an endobenthic marine bivalve species that is abundant in the intertidal and shallow-subtidal zones of eastern Canadian and New England shores. In these coastal environments, clams are subjected to both natural and anthropogenic disturbances that can result in dislodgement from the sediment. This is especially...

In the southern Gulf of St. Lawrence (sGSL), there is a mostly supplementary fishery for sea scallops (Placopecten magellanicus) concentrated on three primary scallop beds in the Northumberland Strait. The fishery is not subject to an enforced minimum size limit and small scallops (<90 mm shell height) are often removed from this population before...

Through physical manipulation, oyster growers can modify the morphological features of young oysters in order to improve their robustness and resiliency to predation. In this study, the efficacy of a novel passive culturing technique using floating buckets that “bounce” oysters prior to the benthic grow-out phase for enhancing shell thickness and s...

In eastern Canada, shellfish culture techniques fall into two categories, off-bottom and bottom. Although off-bottom techniques are increasingly being employed, most of the existing leases are still classified as bottom culture leases. Bottom leases are underutilized due to predation by crustacean predators. Our research aims to develop a seed prod...

Canadian Science Advisory Secretariat Gulf Region Science Advisory Report 2019/006

This report provides insight on feeding pressures of cultivated blue mussels Mytilus edulis and the invasive solitary tunicate Styela clava on phytoplankton and zooplankton, including American lobster (Homarus americanus) larvae (stages I and IV). In 2015-2016, experiments were conducted in a portable aquatic laboratory on Prince Edward Island (PEI...

Bivalve aquaculture is an industry in constant growth in Canada. This growth can be attributed to thanks to the innovation of husbandry techniques, which translates to a slight increase in biomass production annually. This said, inter- and intra-specific competition for food sources is a concern which can have important repercussions on cultured bi...

This report provides a comprehensive overview of cultivated mussel populations suspended from longlines in Prince Edward Island (PEI), Canada. From October 2015 to December 2016, leaseholders from six major mussel-producing embayments were interviewed on a monthly basis to capture information on the content of their leases. In addition, mussels wer...

In this study, we investigated the food sources of eastern oysters Crassostrea virginica cultivated in Atlantic Canada. Stable isotopes (13 C and 15 N) and fatty acid biomarkers were used to identify these sources under in situ conditions for suspended (∼0.5 m below surface) and bottom (∼2 m) culture stocks. It was found that particulate organic ma...

The Eastern oyster, Crassostrea virginica, is cultivated in Atlantic Canada directly on the seabed or in floating cages near the surface. Normally, oysters are considered as herbivores feeding on phytoplankton, using mainly diatoms as their energy source. We tested here two analytical methods on the potentiality of this bivalve species to use other...

Blue mussels (Mytilus edulis) that are cultivated in the marine area around Prince Edward Island, Eastern Canada, are susceptible to the heavy biofouling of their shells by an invasive solitary tunicate, Styela clava, which rapidly proliferates. To mitigate this issue, mussel farmers periodically lift the longlines on which the mussels are suspende...

Like the majority of benthic invertebrates, the blue mussel Mytilus edulis has a bentho-pelagic cycle with its larval settlement being a complex phenomenon involving numerous factors. Among these factors, underwater noise and pelagic trophic conditions have been weakly studied in previous researches. Under laboratory conditions, we tested the hypot...

Autotrophic picoplankton (≤2.0 µm) is one of the most abundant phytoplankton components in marine ecosystems. The contribution of picophytoplankton to blue mussel (Mytilus edulis) growth was investigated in eastern Prince Edward Island, where the bulk of the Canadian suspended mussel industry is located. Field trials using flow cytometry were used...

The role of bivalve mariculture in the CO 2 cycle has been commonly evaluated as the balance between respiration, shell calcium carbonate sequestration and CO 2 release during bio-genic calcification. However, this approach neglects the ecosystem implications of cultivating bi-valves at high densities, e.g. the impact on phytoplankton dynamics and...

Oral presentation at Physiomar-14, La Serena, Chile

A spatially explicit coupled hydrodynamic biogeochemical model was developed to study a coastal ecosystem under the combined effects of mussel aquaculture, nutrient loading and climate change. The model was applied to St Peter’s Bay (SPB), Prince Edward Island, Eastern Canada. Approximately 40 % of the SPB area is dedicated to mussel (Mytilus eduli...

The performance of oysters (Crassostrea virginica) grown at an exposed site at depths of 5 and 10 meters was compared to those grown at a sheltered site at a depth of 1.5 meter. The exposed site was located near Stonehaven and the sheltered site was in Caraquet Bay, both in Chaleur Bay, New Brunswick (NB). Oysters were cultivated using a modified F...

ABSTRACT: Cultivated bivalves rely on natural seston for growth and metabolic processes. Because seston is a limited resource, there is a need to better understand its distribution and fluxes within culture embayments, so farms can be positioned optimally within these dynamic systems. In this study, a simple numerical tool was developed and impleme...

A novel approach to measuring chlorophyll uptake by cultivated oysters

Traditionally, the eastern oyster (Crassostrea virginica) is cultivated in sheltered bays and estuaries. However, a feasibility study was conducted on oysters grown in an exposed (off-shore) environment using the oyster glued on string method. This method consists of gluing oysters in clusters of three with a special cement mixture on stings which...

In the context of resource management and spatial planning, tools are needed to help decision makers assess the potential of coastal areas for various activities. Among these, shellfish culture presents the particularity of exploiting natural resources as well as producing goods and services. Numerical modelling is a powerful tool that is well suit...

Fluorescence characterization of water entering and exiting a blue mussel (Mytilus edulis) aquaculture estuary.

Aquaculture Association of Canada Special Publication. 22, 14–16.

Approximately 73000 Atlantic rock crab (Cancer ir-roratus) were captured in coastal waters and trans-ferred to an estuarine mussel aquaculture site in Prince Edward Island, Canada, in an e¡ort to control overgrowth by the invasive tunicate Ciona intestina-lis. To assess whether transplanted crabs remained in the vicinity of mussel farms, acoustic t...

The Shellfish Monitoring Network (SMN) is a standardized data collection tool for monitoring growth, meat yield and survival of molluscs in Atlantic Canada. The SMN is also useful for documenting water temperature at the sites. Using the American oyster (Crassostrea virginica) as an indicator species, the SMN was evaluated in the southern Gulf of S...

Chlorophyll uptake was monitored in caged oysters (Crassostrea virginica) using in situ fluorometers. Cages were suspended in a dynamic water column environment and allowed to orient freely with the current. Current velocity inside the cages ranged from 1.8 to 11.7 cm s−1. No evidence of feeding stress was found at peak current velocities, a result...

The primary objective of this study was to assess the phytoplankton biomass distribution throughout a blue mussel (Mytilus edulis) seed collection farm using active fluorescence mapping technology. Within the farm we measured a fluorescence depletion of up to 30% compared to outside the farm. The depletion generally extended 10 m past the farm, alt...

The 2008 assessment of the southern Gulf of St. Lawrence snow crab, Chionoecetes opilio, stock (Areas 12, 19, E and F) was based on data from the commercial fishery (fishermen’s logbooks, at-sea observer measurements and quota monitoring reports) and trawl surveys. The 2008 landings in Area 12 were 20,911 t (quota of 20,900 t) with an average catch...

The objective of the study was to determine whether there are differences in Escherichia coli counts in relation to seasonal and/or spatial distribution patterns in a conditional shellfish-growing zone located in the Richibucto estuary, New Brunswick, Canada. E. coli concentrations in surface water, sediments, suspended and bottom cultured American...

This study explored the possibility of using a new technology, called “bouncing buckets,” for Crassostrea virginica larvae remote setting and juvenile nursing in coastal waters. Very low recruitment (< 1%) was quantified through direct deposit of eyed larvae into bucket long lines and downwellers on a floating platform. However, in terms of nursing...

Chlorophyll-a fluorescence mapping in shellfish farms.

In Atlantic Canada, aquaculture of the American oyster 'Crassostrea virginica' is a growing industry with significant economic potential. The objective of the project is to increase the general understanding of spatial and temporal variations of faecal coliform concentrations in open, conditional and closed shellfish aquaculture zones. A comprehens...

In Canada, the sanitary classification of coastal zones distinguishes opened, conditional, closed and prohibited areas for shellfish harvesting. The classification is based on levels of faecal coliform (Escherichia coli) concentration in water and shellfish meat. The general objective of the study was to determine if there are differences in faecal...

Atlantic Provinces coastal zones are classified in three distinct categories: opened, conditional and closed to shellfish harvesting. Classification is mostly based on faecal coliform concentration in water and shellfish. The primary goal of this study was to compare the faecal coliform distribution in four compartments: water, sediments, suspensio...

FAECAL COLIFORMS DISTRIBUTION IN FOUR COMPARTEMENTS: WATER, SEDIMENTS, SUSPENSION AND BOTTOM CULTURED OYSTERS (CRASSOSTREA VIRGINICA) FROM OPENED, CONDITIONAL AND PROHIBITED SHELLFISH HARVESTING AREAS