Canadian Aquaculture R&D Review 2009

Shellfish

Stress effects in shellfish investigated three ways

Responding to an industry-wide need for more efficient ways to evaluate and monitor health states in shellfish, three research teams across Canada have been looking at different aspects of the problem.

Seedstock differences in Newfoundland

DFO’s Dr. Randy Penney, based in St. John’s, Newfoundland, is interested in the reported variability in performance of different mussel seedstocks, some of which comprise two species (Mytilus edulis and Mytilus trossulus), when confronted with stresses related to temperature and salinity. At DFO, Dr. Penney, Dr. Dounia Hamoutene and their team are comparing physiological stress responses (primarily “heat shock protein” Hsp) of several indigenous seedstocks from the Notre Dame Bay area. The team is currently working out some standardized testing protocols for Hsp and other stress proteins in the hopes of developing a quantitative way to identify “hardy” strains that can be used for inter-site transfers, and which may be expected to perform favourably compared to local mixed-species stocks. They hope to provide recommendations to the industry regarding the most desirable stocks for commercial development, and to begin comparative work on stress response in scallops (Placopecten magellanicus).

Behavioural indicators in Quebec

Mussels were also involved in a recently-completed study at the University of Quebec at Rimouski. Noting the difficulties in determining the state of health of individual shellfish outside obvious indicators such as very slow closing of the valves in already-moribund animals, Dr. Rejean Tremblay, Rachel Picard and Bruno Myrand have been seeking a simple, behavioural indicator that could be quantified for intermediate levels of stress between robust health and deep morbidity. They tested the time required for softshell clams (Mya arenaria) to bury themselves, and assessed the strength of attachment and number of byssus threads produced by mussels (Mytilus edulis), after removal from the water for more than three days at 100% humidity. The researchers reported that the behavioural indicators selected were not able to discern various levels of stress in test animals.

A Genome-based model in BC

Dr. Helen Gurney-Smith

A research program (Myt-OME) on the West Coast funded by Genome British Columbia and the BC Innovation Council has taken a different approach to the challenge of quantifying stress responses in shellfish. Led by Dr. Helen Gurney-Smith of Vancouver Island University’s Centre for Shellfish Research and Dr. Stewart Johnson of the DFO Pacific Biological Station, a team of international collaborators is attempting to identify the genes involved in the expression of stress responses.

According to Dr. Gurney-Smith, “Most people have heard the expression ‘happy as a clam’, but the truth is we do not have any tools to determine if a clam is happy (healthy). Genomic science can provide the necessary tools”.

In 2008 an investment of more than $400,000 by the Government of Canada through Western Economic Diversification Canada helped to establish a Shellfish Genomics Laboratory at Vancouver Island University in Nanaimo, BC, where research tools will be developed to diagnose various factors related to transportation, pollution and environment in hatchery-reared larvae and adult shellfish.

In recognition of the many possible overlapping sources of stress arising through environmental conditions, human activities and biological influences such as disease, Dr. Gurney-Smith and her team have launched a major program to develop a genomics tool for use with mussels (Mytilus spp.), a known ecosystem bio-indicator genus. They hope to devise an accurate way to measure the activity of specific genes that are up- and down- regulated in response to a variety of stressors. Once they can measure accurately the genomic biomarkers that respond to multiple-stressing conditions in the marine environment, they will be able to correlate levels of stress with environmental conditions, and to understand what ultimately determines a fatal response. With a sensitive genomics tool applied to a number of “keystone species”, scientists should be able to perform far more accurate and timely health assessments of individual shellfish. This would facilitate assessments of ecosystems in various coastal zones and stocks in aquaculture operations, as well as monitoring of environmental changes and their effects.

Newfoundland study:
Duration: Nov ’08 - Ongoing
Project team: Randy Penney (DFO), Dounia Hamoutene (DFO), Juan Perez Casanova (DFO), Sean Macneill (DFO), Marsha Clarke (DFO).
Funded by: DFO.
For information contact: Randy Penney ( Randy.Penney@dfo-mpo.gc.ca)

Quebec study:
Duration: 2005 – 2008
Project team: Rejean Tremblay (ISMER-UQAR), Rachel Piquard (ISMER-UQAR), Bruno Myrand (CEMIM-MAPAQ). 
Funded by MAPAQ.
For information contact: Rejean Tremblay ( Rejean_tremblay@uqar.qc.ca)

British Columbia study:
Duration: Jan ‘09 – Mar ’10
Report submitted by: Genome British Columbia.
Project team: Helen Gurney-Smith(CSR-VIU), Stewart Johnson (DFO), Ben Koop (UVIC), Antonio Figueras (CSIS-IIM, Spanish Ref. Lab. For Mollusc Diseases, Spain), Crain Newton (ATG Genetics).
For information contact: Helen Gurney-Smith ( Gurneysmh@viu.ca)

Gulf of St Lawrence navigation buoys may serve as mussel spat monitoring tools

Choosing a good mussel culture site is complicated by the lack of prior knowledge of recruitment and growth of spat under farmed conditions. Once established, mussel culture operations also need annually updated information about spat performance. In addition, the approaches generally used in this field are often plagued by problems inherent in monitoring the spatial and temporal variability in the marine environment.

These constraints impose choices that limit the geographic scope of conventional monitoring programs. Without sound data, the industry’s ability to plan its research and development needs is compromised. It is therefore essential to develop effective and economical strategies for studying geographic variations in the recruitment and growth of mussel spat.

This project aims to develop a simple, effective and low-cost method for monitoring recruitment and growth of mussel spat. The team is comparing spat populations from conventional collectors with spat found on navigation buoys at various sites in the Gulf of St. Lawrence. The spat from collectors can be considered to be representative of the aquaculture situation and will serve as a control. The investigation is focusing on the potential usefulness of the navigation bouys for aquaculture monitoring.

Duration: Dec ‘06 – Mar ‘10
Funded by: DFO-ACRDP. Co-funded by: SODIM, RAQ
Project team: Marcel Fréchette (DFO), Martin Guay (CACN), Yannick Goaziou (CACN), François Bourque (MAPAQ), Benoît Thomas (MAPAQ), Ihsène Ben Salah (UQAR-ISMER), Jocelyne Pellerin (UQAR-ISMER), Linda Girard (DFO), Myriam Lachance-Bernard (DFO) 
For information contact: Marcel Fréchette ( Marcel.Frechette@dfo-mpo.gc.ca)

Quebec team investigates the metabolic basis for mussel gaping

(Photo: S. Gauthier-Clerc)

The phenomenon of gaping observed in cultivated mussels in Quebec is a major obstacle to the development of the mussel aquaculture industry as consumers are very reluctant to buy open mussels. Mussels from Prince Edward Island, Quebec’s main competition in this market, are reported to have a significantly lower incidence of gaping. It is therefore critical for the Quebec mussel aquaculture industry to gain an understanding of this phenomenon in order to be able to address it.

The research team is investigating whether the propensity of mussels for gaping is voluntary and occurs when they are exposed to air, resulting from a lack of sufficient oxygen to meet their metabolic needs, or whether it is caused by a decrease in tone of the adductor muscle, which controls valve movement. The appearance of gaping so soon after harvesting suggests that priority should be given to examining this phenomenon.

Several questions are being asked. Does temperature influence the intensity of metabolic activity in mussels and therefore their propensity for gaping? Does icing the mussels with large quantities of ice immediately after they are removed from the water help reduce their metabolic activity, increase their stress tolerance, and decrease their propensity for gaping?

Duration: Jun ‘07 – May ’10. 
Funded by: DFO-ACRDP. Co-funded by: SODIM, RAQ.
Project team: Marcel Fréchette (DFO), Sophie Gauthier-Clerc (ISMER-MAPAQ), Réjean Tremblay (UQAR-ISMER), Francis Coulombe (CTPA-MAPAQ), Sonia Belvin (ISMER-MAPAQ), Marie-Élise Carbonneau (CTPA-MAPAQ), Réjean Allard (Pêcheries R. Allard Inc.), Marie-Gil Fortin (MAPAQ) Nicolas Bouchard (DFO), Linda Girard (DFO)
For information contact: Marcel Fréchette ( Marcel.Frechette@dfo-mpo.gc.ca)

Finding the causal agent of malpeque disease in Nova Scotia oysters

The oyster industry has been plagued on several occasions by a highly infectious Malpeque disease. Initially, the disease appeared in 1915 in Malpeque Bay, PEI, and again in the 1950's and 60's, with losses of up to 90% of affected stocks. Disease tolerance developed over time followed by recovery of most stocks. In 2007, new outbreaks were observed in the Bras D'Or Lakes and St Ann’s Harbour, Cape Breton.

Malpeque disease is believed to be caused by a pathogen, although all attempts to identify the cause of this abnormal condition have been inconclusive. The disease is diagnosed on various gross and histological observations e.g. mantle regression, gaping, nodules in the mantle, accumulation of ceroid-containing cells, haemocyte infiltration and focal haemocyte accumulations.

Researchers are working on a two part investigation leading to the development of molecular-based tools for the diagnosis of Malpeque disease. The first is to confirm the presence of a pathogen in infected oyster tissues by isolating small parts of its genetic material. Using these data, the second part of the project is the development of a PCR-based test to determine the presence or absence of the pathogen from animal tissues.

Duration: May ‘08 – Mar ’10. 
Funded by: DFO-ACRDP. Co-funding: AANS. 
Project Team: Nellie Gagné (DFO), Mark Laflamme (DFO), Roland Cusack (NS DFA) 
For information contact: Nellie Gagné ( Nellie.Gagné@dfo-mpo.gc.ca)

Does mechanical clam harvesting in BC pose any environmental risk?

Mechanical harvester / Clam harvesting

BC shellfish farmers are finding it challenging to compete in the international shellfish marketplace. To increase their competitiveness, the industry must find ways to increase productivity while at the same time reducing harvesting costs. For certain species, the use of a mechanical harvester holds significant promise to increase efficiency and lower costs.

In 2002, Chuckanut Shellfish Inc. modified a mechanical tulip bulb harvester, designed for greenhouse harvest, to successfully harvest Manila clams (Venerupis philippinarum) in Samish Bay, Washington. This machine effectively reduced harvest labour costs to 3-5% of the farm gate value.

Approximately 1,600 metric tonnes of Manila clamsare harvested annually from farms in BC, and the traditional method of harvesting Manila clams is by hand, using rakes. Even though this is the accepted method in BC, an environmental assessment of hand harvesting has not been conducted. Literature on the environmental effects of mechanical harvesting does exist, though much of it is focused on different techniques and species in other areas of the world.
The research team in this project is determining the potential near and far field effects of mechanical and hand harvesting. In particular, they are considering the potential risks to valued habitat productivity, providing the scientific information necessary for the development of appropriate regulatory approval criteria for such activities.

Duration: Jul ‘08 – Jun ’10. 
Funded by: DFO-ACRDP. Co-funded by: BCSGA. 
Project team: Kerra Hoyseth (DFO), Ryan Sherman (DFO), Steven Cross (U Vic), David McCallum (BCSGA), Tom Broadley (BCSGA), Gordy McLellan (Macs oysters), Richard Hardy (Pentlatch Seafood), Bill Taylor (Taylor Shellfish), Chris Pearce (DFO), Bill Heath (BCMAL). 
For information contact: Kerra Hoyseth ( Kerra.Hoyseth@dfo-mpo.gc.ca)

Hand harvesters

Evaluating and optimizing mussel seed quality in Nova Scotia

(Photo: T. Landry)

One of the strengths of the mussel aquaculture industry in Atlantic Canada is the access to an affordable and reliable seed supply. However, this has also generated some concerns over the quality of mussel seed, particularly in relation to the presence of the two Mytilus species; M. edulis and M. trossulus.

Poor seed quality has resulted in crop losses due to high mortality rates, processing difficulties and low market values. Recent work on the seed quality issue is providing mussel farmers with a better knowledge on geographical variability in seed quality in terms of species composition as well as physiological fitness.

Work in this project is focused on the temporal variability of mussel seed. Specifically, researchers are investigating the ratio of M. trossulus and M. edulisand their respective physiological fitness throughout their growth cycle in the natural population and aquaculture sites in Nova Scotia.

Researchers are developing cost-effective and practical approaches to evaluate and optimize seed quality by reducing the percentage of M. trossulus while improving the quality of seed in terms of the physiological fitness. Apart from the clear economical benefits of developing these approaches, there are equally important ecological benefits associated with optimizing seed quality. Improving the efficiency of mussel farms will help optimize the critical ecological services provided by mussels and other filtering animals in aquaculture environment.

Duration: Mar ‘07 – Jun ’09. 
Funded by: DFO-ACRDP. Co-funded by: Darren Porter, NS DFA
Project team: Thomas Landry (DFO)
For information contact: Thomas Landry ( Thomas.Landry@dfo-mpo.gc.ca)

(Photo: T. Landry)

Projects begin to yield results in managing invasive tunicates in PEI

High-pressure washer used to treat mussel socks for ciona. The machine uses two rows of 8 high pressure oscillating water nozzles to clean ciona off the mussel socks as they pass through the vertical chamber suspended from the side of the boat. This picture was taken in Cardigan Bay. The pressure washer belongs to Wayne Chaisson and has proved very effective at cleaning ciona off mussel gear.

A multi-project initiative is yielding innovative equipment and approaches in managing and processing tunicate infested mussel crops in PEI. Over twenty individual projects are currently being conducted to reduce the impact of invasive tunicates on mussel crops and to improve the productivity in infested waters. Technologies to reduce the biomass of tunicates on mussel socks are being transferred, modified and tested.

The industry is focusing its main efforts on two technologies in order to optimize their use in relation to timing and frequency of application, within a sound environmental context. These projects are providing critical information on the effects of these treatment regimes in different geographical areas with varying levels of infestation.

Complementary scientific investigations are providing valuable information on the biology of the invasive tunicate to assist in developing optimal management strategies that will ensure the sustainability of the mussel industry in PEI, as well as other aquaculture industries in Canada affected by aquatic invasive species.

Duration: Jul ‘07 – Mar ’08. 
Funded by: DFO-ACRDP. Co-funded by: PEI DFAE, ACOA, PEIAA
For information contact: Thomas Landry ( Thomas.Landry@dfo-mpo.gc.ca)

Lime treatment system used to treat the clubbed tunicate in Malpeque Bay, recovers the lime in the horizontal part of the mechanism for re-use. This system belongs to Martin MacDonald.

Improved mussel seed supply results from Newfoundland project

An experimental mussel transfer
in Green Bay NL (Photo: DFO)

Newfoundland is a zone of hybridization between two mussel species, Mytilus edulis and M. trossulus and growers currently use seedstocks of mixtures of both species and their hybrids. Low production rates and poor quality product have been associated with stocks of high proportions of M. trossulus. Evidence has shown that culture of monospecific M. edulis stocks has potential to improve industry-wide production and product quality.

The use of transferred monospecific M. edulis stocks by industry has been recommended to replace the current practice of collecting seed on sites with high ratios of M. trossulus. However, monospecific M. edulis stocks have not always consistently out-performed indigenous mixed-species stocks when such seedstocks have been transferred to other growout sites.

There is speculation as to the reasons for this, but genetic variation within the M. edulis genotype is highly suspected. Sources of monospecific or high-ratioM. edulis stocks need to be identified and their performance needs to be tested on recipient sites to determine their true potential as donor seedstock sites.

The research team is searching for and assessing new potential seedstock sources. In addition, they are closely assessing seedstock in relation to existing aquaculture leases to determine their potential for development as future donor sources of high quality seed.

Duration: Apr ‘08 – Mar ’10. 
Funded by: DFO-ACRDP. Co-funded by: NRC-IRAP; MI, CCFI. 
Project team: Randy Penney (DFO), Sean Macneill (DFO), Sharon Kenny (DFO), Marsha Clarke (DFO/NAIA), Kim Hobbs (NAIA), Christopher Dawe (MI), Darryl Green (NAIA), Tom Brown (MI), Chris Brown (NRC), David Innes (MUN), Marc Kielley (CCFI). 
For information contact: Randy Penney ( Randy.Penney@dfo-mpo.gc.ca)

Research aims to control epibionts on mussel spat collectors

Mussel spat collectors with heavy set of mussel spat completely covered by a dense population of skeleton shrimp. (Photo: C. Turcotte)

Epibionts can have a significant effect on mussel spat collection and growth. Researchers are examining interactions between skeleton shrimp, hydrozoans and mussels at mussel culture sites in Cascapédia and Gaspé bays. Improving the basic knowledge about these epibionts is helping to verify the effectiveness of an epibiont control protocol and is leading to the development of criteria for determining whether “treatment” is worthwhile, based on a cost/benefit analysis over time periods representative of mussel spat collection and socking operations.

During the course of this project, the research team is documenting the biology, ecology and spatial and temporal variability of the establishment of undesirable epibiont communities. They are testing the hypothesis of a negative effect of skeleton shrimp and hydrozoans on mussel spat collection and growth in the short term (intra-season) and in the long term (spat collection and socking) and quantify the impact.

They are also exploring the trophic dynamics of epibiont communities on spat collectors and, the case arising, determining the mechanism by which skeleton shrimp impact spat collection and growth (predation and/or competition for food). Finally, they are verifying the effectiveness of early bringing in for controlling epibionts and propose decision-making rules based on the impact and costs for various “infestation” thresholds.

Duration: Apr ‘07 – May ’10.
Funded by: DFO-ACRDP. Co-funded by: DFO-AIS.
Project team: Bernard Sainte-Marie (DFO), Christian Turcotte (UQAR), Réjean Tremblay (UQAR), Fabrice Pernet (IFREMER, Sètes)
For information contact: Bernard Sainte-Marie ( Bernard.Sainte-Marie@dfo-mpo.gc.ca)

Female skeleton shrimp: Mature female skeleton shrimp (Caprella mutica about 12 mm total length excluding antennules) showing well developed brood pouch. (Photo: T. Gosselin)

Project investigates sources of impacts to clam gardens in the Broughton Archipelago

Concern has been raised by Broughton Archipelago First Nations (‘Namgis and Kwicksutaineuk-Ah’kwak’ah’mish First Nations) about changes to the productivity of a number of clam beaches and culturally modified clam terraces within their Traditional Territories.
The concern centers on the possibility of impacts to clam populations from commercial salmon farms in the Broughton Archipelago. In addition to salmon farming, the range of possible human disturbances in this region includes forestry impacts, such as watershed logging and sediment deposition, log handling and storage activities, and woody debris buildup in the marine environment.

Desired outcomes of this project are to understand the forces that shape and impact the populations of bivalves in the study area with special reference to the potential effects of salmon farms. Of equal importance is the development of a hierarchical ranking of factors that influence intertidal clam populations. In addition, future considerations for long-term monitoring or mitigative procedures to suspend or reverse further loss of clam productivity and quality standards will be outlined.

Duration: Nov ‘07 – Sep ’10. 
Funded by: DFO-ACRDP. Co-funded by: Marine Harvest Canada Inc. 
Project team: Terri Sutherland (DFO), Sharon Dedominicis (Marine Harvest Canada Inc.), Clare Backman (Marine Harvest Canada Inc.), Marty Weinstein (M.S. Weinstein Consulting Services), Doug Aberley (‘Namgis Nation Representative), Jason Dunham (DFO), Curtis Roegner (NOAA Fisheries Service), John Harper (Coastal and Ocean Resources Inc.), Barry Hargrave, Shawn Robinson (DFO), Kevin Butterworth (BC CAHS), Eric McGreer (BC MoE).
For information contact: Terri Sutherland ( Terri.Sutherland@dfo-mpo.gc.ca)

Developing strategies to optimize shell growth performance and quality of near market size oysters

OysterGro cages temporarily upside-down for eliminating fouling organisms

In this 18-month study, researchers explored the efficacy of different grow-out methods, anti-fouling techniques and grading strategies for the purpose of augmenting the production of market-size oysters grown in suspended culture in Baie St-Simon in northern New Brunswick.

They are documenting the annual shell growth of various size classes using individually-labeled oysters deployed in various systems including floating bags, oyster tables, OysterGro cages and Dark Sea trays.

In addition, the team is evaluating the effectiveness of brine dipping and/or air exposure for eliminating various fouling organisms including oyster spat, barnacles, mussels and boring sponge.

Work is also being done to evaluate three grading strategies for oysters larger than 50-mm. The three methods are mechanical grading in spring (mid-June 2008), mechanical grading in fall (mid-September 2007), and no grading where oysters were left in bags and fouling organisms were eliminated via bag flipping/brine dipping.

Duration: Apr ‘07 – Mar ’09. 
Funded by: DFO-ACRDP. Co-funded by: L’Étang Ruisseau Bar Ltd. 
Project team: Marie-Hélène Thériault (DFO), André Mallet (L’Étang Ruisseau Bar Ltd.)
For information contact: Marie-Hélène Thériault ( Marie-Helene.Theriault@dfo-mpo.gc.ca)

American Oyster growth

Do New Brunswick biofouling control methods impact oyster productivity?

Hot water bath for control of biofouling organisms. Conveyor belt drives Vexar® bags in hot water

In New Brunswick, the farming of eastern oysters (Crassostrea virginica) is mainly carried out using floating Vexar® bags. This technique allows for easy access to stocks, reduces predation, and promotes growth by maintaining the oysters in relatively warm and phytoplankton-rich surface waters.

Nonetheless, floating bags are vulnerable to fouling organisms and researchers in this project are investigating whether biofouling control methods such as desiccation and heat exposure significantly impact oyster productivity.

Bags provide a good recruitment substrate for wild mussel larvae (Mytilus edulis). They are also susceptible to other fouling organisms, such as barnacles (Semibalanus balanoidesBalanus balanusBalanus crenatus), wrinkled rock borers (Hiatella arctica), and wild oysters. Fouling organisms grow rapidly during summer, compete for the same food resources as oysters, and ultimately obstruct water flow.

Growers mitigate the biofouling problem by exposing bags to air for three days, a desiccation approach that is quite labor-intensive. Another mitigation measure presently being developed by the industry consists of briefly exposing fouled bags (containing oysters) to heat (50 - 80ºC).

Duration: Jun ‘08 – Aug ’10. 
Funded by: DFO-ACRDP. Co-funded by: NBPSGA 
Project team: Luc Comeau (DFO), Elise Mayrand (U Moncton), Tina Rousselle (DFO), Léon Lanteigne, Maurice Daigle (Aquaculture Acadienne Ltee.).
For information contact: Luc Comeau ( Luc.Comeau@dfo-mpo.gc.ca)

Oyster bag fouled with mussels

Can culture density be increased for oysters in New Brunswick?

Floating oyster bags in New Brunswick

In New Brunswick, oysters are primarily grown in floating Vexar® bags attached to longlines. A recent aerial survey indicated that growers deploy bags at an average density of 2,000 bags per hectare. This density is strikingly low compared to other oyster farming areas, such as in France where average stocking density is reportedly 5,000 bags per hectare.
The rationale for conducting the present investigation is based on a proactive strategy for shellfish management in NB, considering that the NB oyster industry is still developing, and that control sites are readily available to carry out impact studies using robust designs such as BACI (Before-After-Control-Impact).

This project is evaluating the effects of increasing stocking densities on oyster productivity (e.g., shell growth) and the environment (e.g., biodeposition). In these trials, stocking densities are being increased well beyond current levels in NB and the effects are being monitored over a three-year period.

Duration: Jun ‘08 – Mar ’12. 
Funded by: DFO-ACRDP. Co-funded by: NBPSGA. 
Project team: Luc Comeau (DFO), André Mallet (Mallet Research Services Ltd.), Claire Carver, Sylvio Doiron (NB DAA)
For information contact: Luc Comeau ( Luc.Comeau@dfo-mpo.gc.ca)

Oyster tables in Marennes-Oléron (France)

BC project works out cockle hatchery production techniques

Cockle (Photo: CSR)

There is significant interest in the commercial cultivation of the basket cockle (Clinocardium nuttalli) within British Columbia. This is due to several factors, including its relatively fast growth rate, its ability to utilize various substrata, its adaptation to grow and survive in the cold waters of the coast of BC and Alaska, and its importance as a preferred First Nations’ food group.

This targeted project is designed to investigate the optimal hatchery rearing conditions for this species, building on previously established work on broodstock conditioning and the early embryogenesis phases.

Research is underway into the optimal species composition and ration of microalgal cells for growth and survival of both larvae and post-larvae (up to 2 mm in length). In addition, work is being done on optimal rearing densities and rearing temperatures for both larvae and post-larvae of this species.

Duration: April ‘07 – Jun ’09.
Funded by: DFO-ACRDP. Co-funded by: CSR-VIU. 
Project team: Helen Gurney-Smith (CSR-VIU), Chris Pearce (DFO), Wenshan Liu (CSR-VIU), Don Tillapaugh (CSR-VIU), Andrew Dryden (Evening Cove Oysters).
For information contact: Helen Gurney-Smith ( Helen.Gurney-Smith@viu.ca)

Can manipulation of culture depth reduce summer mortalities in Pacific oysters?

Oyster growers in British Columbia normally lose approximately 10% of their stock in raft-based operations during the summer. Transient periods of very high temperature and the occurrence of harmful algal blooms can cause a massive increase in the mortalities, decimating oyster stock by as much as 50 to 100%.

Researchers are proposing a management option to mitigate the impact of these two environmental factors. It involves lowering oyster culture trays to a depth where the temperature is lower and harmful algae are less concentrated. This is to be done as soon as the temperature and seawater transparency reach certain critical values. The caveat of this method is that normal phytoplankton are also concentrated close to the water surface, and lowering the oysters would take them out of reach of their food source, thus reducing their growth.

In order to find the optimum balance between oyster mortality and growth, it is necessary to find the optimum depth to which the oysters should be lowered in conjunction with the temperature shift that should be triggered by the change of depth. This investigation is geared to study this problem with scientific methods applied to farm conditions throughout the Strait of Georgia. The results of this research will allow oyster growers to make management decisions to reduce the mortalities in their stock based on simple environmental monitoring and tray movement.

Duration: Jun ‘08 – Jul ’09.
Funded by: DFO-ACRDP. Co-funded by: BCSGA, Mac’s Oysters Ltd. Taylor Shellfish Canada.
Project team: Maite Maldonado (UBC), Chris Pearce (DFO), David Cassis (UBC)
For information contact: Chris Pearce ( Chris.Pearce@dfo-mpo.gc.ca)

BC project investigates conditions for optimal on-growing of the basket cockle

The basket cockle, Clinocardium nuttallii, occurs on the Pacific coast of North America from San Diego to the Bering Sea. In British Columbia there is significant commercial interest in basket cockles as an aquaculture species as a result of their relatively fast growth rate, ability to utilize different substrata, adaptation to the cold waters of BC, and importance as a preferred First Nations’ food group.

Researchers are investigating the optimal on-growing conditions for this species, building on previously established work on broodstock conditioning, embryogenesis, and hatchery development.

The project combines laboratory and field-based studies on optimal on-growing conditions. Laboratory research is investigating the optimal seed rearing techniques for maximized production in the hatchery, the growth and survival of cockle seed in different substrata, and the post-settlement movement of these motile bivalves. Field studies are determining the optimal seed size, densities, season, and site for transplantation. In addition, the team is looking at optimal on-growing aquaculture husbandry methods (intertidal or off-bottom suspension culture).

This project is yielding valuable recommendations for the management and sustainable production of basket cockles through the responsible development of a new native aquaculture species of cultural significance.

Duration: Aug ‘08 – Oct ’09.
Funded by: DFO-ACRDP. Co-funded by: CSR-VIU. 
Project team: Helen Gurney-Smith (CSR-VIU), Chris Pearce (DFO), Anya Epelbaum (CSR-VIU),
Don Tillapaugh (CSR-VIU), Andrew Dryden (Evening Cove Oysters)
For information contact: Helen Gurney-Smith ( Helen.Gurney-Smith@viu.ca)

Research team assesses impacts of geoduck harvesting

Geoduck harvest impacts (Photo: DFO)

There has been widespread interest in the culture of the Pacific geoduck clam (Panopea abrupta) within British Columbia for a number of years. However, the commercial-scale development of this species has been hindered by a lack of governmental policy/legislation and concerns around how geoduck culture and harvest will impact the environment.

These concerns are generally focused on the harvesting process, as high-pressure water hoses (“stingers”) are used to liquefy the substratum around the clams in order to extract them. This technique is used by aquaculturists as well as the wild fishery.

Researchers are assessing the effects of geoduck clam harvest on the benthic sedimentary environment, nearby eelgrass beds, and the suspended sediment concentration. In addition, they are examining how these effects vary spatially and temporally at both intertidal and subtidal study sites.

The outcomes are anticipated to enable government agencies to make informed decisions about the potential expansion of geoduck aquaculture in BC in both intertidal and subtidal sites.

Duration: Sep ‘08 – Dec ’10. 
Funded by: DFO-ACRDP. Co-funded by: BCMAL, West Coast Geoduck Research Corp., Abrupt Shellfish Inc. 
Project team: Chris Pearce (DFO), Wenshan Liu (CSR-VIU), Miriam O (DFO), Grant Dovey (Resource Consulting Inc.), Bruce Clapp (West Coast Geoduck Research Corp.), Michelle James (West Coast Geoduck Research Corp.), Sean Williams (Abrupt Shellfish Inc.)
For information contact: Chris Pearce ( Chris.Pearce@dfo-mpo.gc.ca)

Bay of Fundy project aims to enable over-wintering of juvenile soft-shell clams

Biologist from Eastern Charlotte Waterways examining experimental clam plots for survival of the over-wintering clam seed.

Researchers are seeking to determine the optimal over-wintering techniques for juvenile soft-shell clams in the Passamaquoddy Region. A key outcome of the project is to establish and maintain a reliable hatchery source and transport of juvenile clams for the clam industry in Southwest New Brunswick.

The team is investigating techniques that yield the highest survival rates. They are transplanting over-wintered hatchery spat to the Lepreau Harbour lease site (MS 1113) and monitoring post-seeding survivorship through seasonal sampling. Pending the success of this technique, the project aims to develop this technology on a larger scale that can support the industrial demand.

Over-wintering soft-shell clams in the Bay of Fundy can yield reasonably high survival levels (~80%) with an anchored, submerged floating cage system. Keeping the cages anchored from the bottom and floating at a depth of at least 15 meters from the surface at mean low water would provide the most stable environment and highest survival of soft-shell clams. Over two years, mortality results from clams sampled in Lepreau Harbour lease averaged ~18.5% each year. The result of this initial work is now leading to work in other areas of the Bay of Fundy.

Duration: Dec ‘06 – Mar ’09.
Funded by: DFO-ACRDP. Co-funded by: Eastern Charlotte Waterways Inc..
Project team: Shawn Robinson (DFO), Benny Travis (Eastern Charlotte Waterways Inc.), Karl Whelan, Jeremy Matheson, Dan McGrattan, Laura Barrett, Eastern Charlotte Waterways Inc. 
For information contact: Shawn Robinson ( Shawn.Robinson@dfo-mpo.gc.ca)

Shot of the experimental clam plot in Lepreau Basin, Bay of Fundy, showing the netting covering the area to exclude predators from the newly planted juveniles. Notice the boot mark for scale.

Team studies impact of cultured mussels and exotic tunicates on plankton communities in PEI

Constructed mussel socks in mesocosms to evaluate the influence of mussels and associated exotic tunicates on plankton communities, PEI (Photo: M. Lecuona)

Ecological principles suggest that suspended mussel culture will have a direct influence on planktonic communities via predation and grazing by the mussels. A number of cascading effects may also influence this. One recent suggestion is that mussels will influence the size structure of the plankton. This, in turn, may influence the ability of exotic tunicates to establish and out-compete the farmed mussels as the tunicates may feed on smaller sized organisms/particles.

In this study, researchers are assessing the influence of mussels and/or associated tunicates on plankton community size structure. They are placing purpose-built small mussel socks in mesocosms for 1 hour periods and comparing the abundance and size-structure of the communities before and after the socks are introduced into the mesocosms and among treatments.

Trials consist of mussels only, inert controls, inert controls with tunicates, and mussels with tunicates. Both of the species Ciona intestinalis and Styela clavaare used independently for a total of 8 treatments.

This work is helping to better understand the interactions between farmed mussels and invasive tunicates as well as their impact on planktonic communities.

Duration: Apri ‘08 – Mar ‘09. 
Funded by: CAISN. Co-funded by: DFO. 
Project team: Chris McKindsey (DFO), Mayi Lecuona (DFO), Mathieu Huot (DFO). 
For information contact: Chris McKindsey ( Chris.McKindsey@dfo-mpo.gc.ca)

Team develops indicators to monitor phytoplankton depletion by mussels

Filter-feeding by mussels naturally results in some local reduction (depletion) of their phytoplankton food supply. If the spatial scale of phytoplankton depletion includes a significant fraction of the coastal inlet, this effect on the base of the marine food web raises concerns about the ecological costs to other components of the ecosystem. These costs can be used to define the “ecological carrying capacity” of the site.

Phytoplankton depletion was documented at mussel aquaculture farms in Canada and Norway using a computer controlled, towed undulating vehicle (BIO-Acrobat) that permitted rapid 3-D mapping of phytoplankton variations over farm to coastal ecosystem scales. Intensive mussel culture activities not only significantly affected phytoplankton concentration at the coastal ecosystem scale under some conditions, but also markedly altered the size of the phytoplankton.

Six PEI embayments were surveyed in August 2008. Researchers found that the bays that are at the highest risk of significant bay-wide particle depletion from mussel culture were dominated by small species (picophytoplankton; 0.2 – 2.0 µm cell diameter). These results indicate a significant destabilization of the basis of the marine food-web that can be monitored using identified indicators and ecosystem persistence targets.

Duration: Jan ’07 – Dec ‘09
Funded by: DFO. Co-funded by: NNRC (Norway) 
Project team: Peter Cranford (DFO), William Li (DFO), Øivind Strand (IMR Norway), Tore Strohmeier (IMR Norway) 
For information contact: Peter Cranford ( Peter.Cranford@dfo-mpo.gc.ca)

Moncton team develops rapid identification technique for larval scallops

Two species of scallop, Placopecten magellanicus and Chlamys islandica, are commercially exploited in eastern Canada. P. magellanicus is found on the Atlantic coast of North America from North Carolina to Newfoundland. C. islandica has a more northern distribution ranging from Greenland to Massachusetts.

Juvenile recruitment with spat collectors is used for stocking natural beds and for aquaculture ventures. Collecting sites may yield very different proportions of P. magellanicus and C. islandica individuals. A method for the rapid and specific quantification of each species from a sample of larvae would help to prevent the use of collectors where the recruitment of the preferred species is not optimal. This method would also replace the Time-consuming process of visually identifying and counting larvae under a microscope.

With the use of fluorescent probes, a real-time PCR is being developed for the purpose of specifically identifying the ratio of each species in a mixed sample. The assay is being tested and validated using samples collected in various areas of eastern Canada.

Duration: Sep ‘08 – Mar ‘09
Funded by: DFO Co-funded by: University of Moncton 
Project team: Nellie Gagné (DFO), Mark Laflamme (DFO), Monique Niles (DFO), Kynan Philippe (Undergraduate student, U Moncton)
For information contact: Nellie Gagné ( Nellie.Gagne@dfo-mpo.gc.ca)

Researchers attempt to get ahead of invasive tunicates in BC

There are at least four species of tunicates in British Columbia which are non-native and potentially invasive: the solitary tunicate Styela clava (club tunicate) and the colonial tunicates Botrylloides violaceus (violet tunicate), Botryllus schlosseri (golden star tunicate), and Didemnum sp.. Recent monitoring surveys have detected some of these tunicate species at a variety of shellfish culture leases and marinas around British Columbia.

However, it appears that they have not had the same impact on this coast as they have in Prince Edward Island and Nova Scotia. This raises questions about the factors controlling invasion success and establishment. Research of basic tunicate biology and ecology is being aimed at resolving these questions.

Researchers in this project are examining how survivorship, growth, and reproduction of tunicates are affected by predation intensity and changes in environmental conditions, such as temperature and salinity. Results from these experiments should allow the team to assess the ability of these tunicates to invade new habitats and the threat that they may pose to other benthic invertebrates within the ecosystem. The research should also enable development of mitigation strategies to prevent further spread of these non-indigenous species and the potential economic impact they may have on the shellfish culture industry of British Columbia.

Duration: Aug ‘06 – Mar ’09 
Funded by: DFO-AIS
Project team: Chris Pearce (DFO), Tom Therriault (DFO), Anya Epelbaum (CSR-VIU), BCSGA
For information contact: Chris Pearce ( Chris.Pearce@dfo-mpo.gc.ca)

Quebec project applies novel approach to understand nutrients and mussel culture

Simplified web of trophic relationships in mussel aquaculture. Grey boxes refer to research sub-projects (Photo: G Fussman)

The future of aquaculture is dependent upon research that leads the way to economically efficient yet environmentally sustainable methods of production. One approach to achieving this goal lies in understanding and managing aquaculture facilities as a food-web that is embedded in the natural, spatially extended, marine ecosystem.

In cooperation with the mussel aquaculture industry on the Magdalen Islands, the team is conducting experimental research that applies the principles of food web and ecosystem ecology. The investigation is exploring how the flows of matter and energy across the food web can be managed in a way that results in an increased production of high-quality, harvestable shellfish. This approach is novel in that it goes beyond examining these processes at the scale of the individual mussel. Rather, it attempts to understand the process of shellfish production in an ecosystem context.

Specifically, the team is looking at the links between cultured mussels and planktonic communities, impacted directly through grazing and indirectly through altering nutrient fluxes. In addition, they are investigating how these nutrient fluxes in turn influence planktonic communities which then influence the mussels. This research is expected to have a strong influence on government policy and eventually translate into novel production methods for Canadian shellfish aquaculture. The team describes their project as AQUAMAN: aquaculture of Mussels And Nutrients.

Duration: Sep ‘08 – Jun ‘11
Funded by: NSERC. Co-funded by: DFO, SODIM, Moules de culture des Iles
Project team: Gregor Fussmann (McGill U), Philippe Archambault (UQAR-ISMER), Connie Lovejoy (U Laval), Bruno Myrand (MAPAQ), Chris McKindsey (DFO), Stéphane Plourde (DFO), Réjean Tremblay (UQAR-ISMER), Michel Fournier (Moules de culture des Iles)
For information contact: Gregor Fussmann ( gregor.fussmann@mcgill.ca)

BC group looks for ways to improve geoduck broodstock performance

Researchers are aiming to find which factors promote maximum fecundity and egg quality in a hatchery setting for broodstock geoduck clams, (Panopea abrupta). They are looking at the effects of various temperature, salinity and nutritional regimes on gonad development. The ranges of temperature and salinity are selected to reflect those typical of an estuarine environment in British Columbia (7 to 19˚C and 17 to 30 ppt, respectively).

Quality of nutrition is being manipulated by presenting live algal feeds that vary in levels of essential fatty acids, namely docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Various rations are also being administered to the broodstock to manipulate caloric intake.

To quantify the effects of the various treatments on gonad development, several indicators are being examined for use. These include histological examination, oocyte diameters, gamete occupation indices, gonadosomatic indices, oocyte per follicle counts, and biochemical composition of gonad tissue.

Duration: Jan ‘06 – Mar ’10. 
Funded by: NSERC Discovery Grant. Co-funded by: DFO. 
Project team: Chris Pearce (DFO), Scott McKinley (UBC), Rob Marshall (UBC)
For information contact: Chris Pearce ( Chris.Pearce@dfo-mpo.gc.ca)

Research uncovers potential for purple sea urchin culture in BC

Purple Sea Urchin (Photo: DFO)

In the development of aquaculture of any new species for culture, one of the major obstacles to overcome is the production of healthy juveniles. Although information about the reproduction cycle and spawning of potential commercial species of sea urchins is readily available, information about larval culture and juvenile grow out are still scarce, especially for the purple sea urchin (Strongylocentrotus purpuratus).

As a first step to developing the purple urchin as a potential new candidate for aquaculture in British Columbia, this project is focusing on broodstock conditioning and larval/juvenile rearing.

The project is investigating four key questions: What are the effects of various feeds (kelps and prepared diets) and temperature on gonad production? What are the effects of different natural feeds, feed rations, densities, and temperatures on growth and survival of larvae? What are the effects of various natural and artificial substrata on larval settlement and metamorphosis? What are the effects of various feeds and temperature on growth and survival of juveniles and adults? s

Duration: Sep ’06 – Mar ’10
Funded by: OSAP. Co-funded by: DFO. 
Project team: Chris Pearce (DFO); Scott McKinley (UBC), Kalam Azad (UBC)
For information contact: Chris Pearce ( Chris.Pearce@dfo-mpo.gc.ca)

Mussel site in Nova Scotia to validate environmental assessment and monitoring

The largest single mussel aquaculture application in the Maritimes was approved in 2003 for St. Anns Harbour, NS after an extensive assessment of environmental risks and the implementation of a rigorous environmental monitoring program.

Now that the mussel leases are developed, an extensive environmental sampling program is being conducted to test both the environmental impact assessment predictions and the effectiveness of the environmental monitoring program design. The data collected will help to advance regulatory science and improve regulatory certainty among stakeholders. Major stakeholders are jointly coordinating this large project.

Duration: Sep ‘08 – Mar ‘09. 
Funded by: DFO-PARR 
Project team: Peter Cranford (DFO), William Li (DFO), Brent Law (DFO), Joe Crocker (DFO), Dawn Sephton (DFO), Barry Hargrave (DFO), Toby Balch (NS DFA), Robin Stewart (Bounty Bay Shellfish Inc), Jon Grant (Dalhousie U)
For information contact: Peter Cranford ( Peter.Cranford@dfo-mpo.gc.ca)

Estimating fall-off of mussels cultured on self-operating collectors

In Carleton (Chaleur Bay, Quebec), some mussel farmers are using the self-operating collector method, which consists of culturing mussels on collectors without adjusting the density. This results in a decrease in population density due to a self-thinning process. Differences in the number and size of mussels that fall to the bottom depend on whether socks or self-operating collectors are used.

Mussel fall-off with self-operating collectors can be calculated based on the principle of self-thinning. The necessary data are currently available in a publication in preparation by Lachance-Bernard et al.. However, there are at present two possible approaches to calculation.

The goal of this project is to determine the best approach and to provide a preliminary estimate of the fall-off process. The requisite samples are obtained by divers in order to minimize mussel fall-off during sampling. This work is a preparatory stage for comparison of the ecosystem effects of conventional suspension culture and mussel culture using self-operating collectors.

Duration: Sep ‘08 – Mar ‘09. 
Funded by: DFO-PARR 
Project team: Marcel Fréchette (DFO), Linda Girard (DFO), Myriam Lachance-Bernard (DFO), Marine de Roumefort, Éric Bujold (Ferme maricole du Grand Large, Carleton)
For information contact: Marcel Fréchette ( Marcel.Frechette@dfo-mpo.gc.ca)

Development of genomic tools enable little neck clams to be ecosystem bioindicators

Often referred to as keystone species, bivalves are major components of coastal and estuarine ecosystems and play a prominent role in the development of ecosystem health indices and values, which can then be applied to ecosystems in general.

It is well documented that stressful environmental conditions (natural or man-made) affect aquatic animal physiological performance (e.g., growth and fecundity), health and survival. Unlike finfish, for which sensitive biochemical assays, genomic tools and visual indicators of stress are available, there are few informative and reliable tools for bivalves.

Researchers in this BC project are developing genomic tools to aid in the study of native little neck clam responses to environmental and anthropogenic stress factors. These tools will facilitate the use of this species as a bio-indicator in the assessment of ecosystem health and resilience in the presence of aquaculture operations.

Duration: Sep ‘08 – Mar ’09. 
Funded by: DFO-PARR 
Project team: Stewart Johnson (DFO), Terri Sutherland (DFO), Helen Gurney-Smith (CSR-VIU) 
For information contact: Stewart Johnson ( Stewart.Johnson@dfo-mpo.gc.ca)

Quebec project re-visits research on dredge harvesting of soft-shell clams

One of the upcoming aquaculture activities in Quebec (and elsewhere) is the development of soft-shell clam (and related) farming in intertidal or shallow subtidal areas. The impacts of this type of work are likely to be associated with harvesting when this is done by hydraulic rake, as is often done in Quebec.

However, the work to date on the impacts of harvesting by hydraulic rakes has been done in more dynamic systems such as environments with strong currents and coarse sediments and/or studies have only been done over very short time scales. To address this gap, a study was done in Quebec in 2003 to evaluate the impact of harvesting clams by hydraulic rakes on benthic communities in local conditions (sandy sediments in low energy systems) as well as the recovery of the communities. The study was done at 2 different times of the year to evaluate temporal differences in impacts and recovery.

This new project is analysing and publishing the results of this research, which is increasingly important for understanding potential impacts and possible ways to mitigate them.

Duration: Sep ‘08 – Mar ’09 
Funded by: DFO-PARR Co-funded by: DFO-ACRDP, SODIM, DFO. 
Project team: Chris McKindsey (DFO), Lizon Provencher (DFO), Mathieu Huot (DFO) 
For information contact: Chris McKindsey ( Chris.McKindsey@dfo-mpo.gc.ca)

DFO team updates southern gulf of St. Lawrence region shellfish monitoring network

SMN Coverage

The shellfish aquaculture industry has grown significantly over the last decades and has become an important part of the economy in eastern Canada. Concurrently, the Habitat Protection and Sustainable Development (HPSD) section is required, under the Fisheries Act and the Canadian Environmental Assessment Act (CEAA), to conduct environmental risk assessments of these activities on the marine habitat. They need scientific advice that will provide them with efficient tools and indicators that will enable them to respond adequately to these requirements.

One concern is in the potential effect of increasing the shellfish biomass on the carrying capacity of estuaries. A proposed tool to address this issue is the Shellfish Monitoring Network (SMN) which is based on a standardized method that measures the productivity of a sentinel species, such as the American oyster, as an ecosystem indicator. This method of examining the spatial and temporal variations in shellfish productivity has been conducted in the southern Gulf of St. Lawrence region on an experimental level since 1995.

This project is focused on the consolidation of the data collected through the SMN. The strengths and weaknesses of this tool are being analysed in the context of the current HPSD requirements. On the basis of this analysis, the requirements for a long-term and sustainable SMN are being designed.

Duration: Sep ’08 – Mar ’09
Funded by: DFO-PARR 
Project team: Marc Ouellette (DFO), Luc Comeau (DFO), Guy Robichaud (DFO)
For information contact: Marc Ouellette ( Marc.Ouellette@dfo-mpo.gc.ca
Website: http://www.glf.dfo-mpo.gc.ca/os/smn-rmm/index-e.php

Oyster Condo Fouling

Eel Lake Oyster Farm's Anti-fouling device

Eel Lake Oyster Farm, under the direction of Nolan D’Eon (owner/operator), is developing an environmentally-friendly machine to eradicate invasive species in the oyster industry. Currently, there is a problem that needs to be addressed due to the increasing invasive species in the waters of Eel Lake, Yarmouth county, Nova Scotia.

The project is exploring using the current water table and a heating method to control invasive species without the use of pesticides or toxins.

Duration: Sep ‘08 – Mar ’09
Funded by: DFO-AIMAP. Co-funded by: Eel Lake Oyster Farm
Project team: Nolan D’Eon, Colton D’Eon, Clark D’Eon (all of Eel Lake Oyster Farm)
For information contact: Nolan D’Eon ( nolandeon@eastlink.ca)

New raft designs in the works for BC shellfish industry

Preliminary simulations. Each string represents the mass and drag of a typical oyster tray stack.

The goal of this project is to develop new high quality shellfish aquaculture raft designs for the BC shellfish farming industry using state-of-the-art materials and techniques to enhance economic profitability and environmental sustainability. Vancouver Island University’s Centre for Shellfish Research and the BC Shellfish Growers Association, together with industry members, are working with Dynamic Systems Analysis (DSA) to develop these new designs.

Through computer simulations, Ryan Nicoll of DSA is able to anticipate problems and identify successes with different raft design components and materials. Once suitable designs have been selected, the CSR will fabricate and test prototypes at the Deep Bay Field Station. A final report will be prepared including construction plans for the industry.

Work has been done on the preliminary stages in the simulations. Information has been provided by industry on the current most typical raft designs. The mass and drag of a typical oyster tray stack has been used to develop a computer-generated simulation of how it performs in the natural environment.

Once the simulation is constructed, DSA can change stresses (waves, currents etc…), loadings and construction materials to see how the raft performs. Optimal designs will then be developed and different construction materials will be tested to determine an optimum cost benefit ratio.

Duration: Aug ‘08 – Mar ‘09
Funded by: DFO-AIMAP. Co-funded by: CSR-VIU, experts, and stakeholders. 
Project team: Brian Kingzett (CSR-VIU), David McCallum (BCSGA), Stellar Bay Shellfish, Barr Plastics, Seaco Marine, CSR-VIU, UVic Innovation and Development Corporation
For information contact: Brian Kingzett ( Brian.Kingzett@viu.ca
Website: PbWiki site, contact Joy.Wade@viu.ca for access

Productivity improvement through mechanization and automation of mariculture operations

Quebec mussel growers have observed that significant mussel losses can occur during harvesting of commercial-sized mussels, especially during summer. SODIM’s mariculture engineer and the Halieutec Inc. team are investigating a harvesting system developed in the Netherlands that uses the venturi effect. A technology transfer mission was therefore organized to Ireland, where some mussel growers have adopted this system.

A venturi system was acquired and modifications begun, including replacing the original 8-inch diameter harvesting pipe with a 10-inch one, which was necessary because of the size of the socks used in Quebec mussel farms. Halieutec then determined the extent of the reduction in losses due to mussel fall-off as well as the time saved in harvesting mussel spat and commercial-sized mussels.

The results obtained during sea trials conducted in the summer of 2008 are encouraging. Harvesting can be carried out 3.5 times faster compared to the conveyor system, though further trials are necessary to validate these results.

Concurrent with these trials, another project conducted by MAPAQ’s Centre Technologique des Produits Aquatiques(CTPA) is measuring the impact of harvesting using this system on the commercial characteristics of marketed mussels – the incidence of gaping, broken shells, product uniformity, and shelf life.

Other related parts of this major project are also underway. These include development of a cleaner for floating line buoys. Another product of the project is a system to avoid tangling of the cords of submerged lines in order to avoid work stoppages during water operations. Scallop farms in Quebec are also now testing scallop production using the ear-hanging technique. Finally, a hydraulic rake is being developed to reduce manpower costs and increase the efficiency of harvesting soft-shell clams.

Duration: Jul ‘08 – Mar ‘10 
Funded by: EPAQ. Co-funded by: DFO-AIMAP, Québec shellfish producers 
Project Team: Sylvain Lafrance (SODIM), Robert Vaillancourt (SODIM), Marie-Joëlle Leblanc (Halieutec Inc.) 
For information contact: Sylvain Lafrance ( sylvain.lafrance@sodim.org
Website: http://www.sodim.org/

Quebec mussel growers see development of farm management software on the horizon

(click on image to enlarge)

At present, shellfish farmers have no effective computer tools to manage their mariculture equipment and mollusc stocks. This project is designing software to manage the shellfish farming equipment and operations (long lines and mussel socks) used in mussel culture, whether in continuous or traditional socks or on long lines.

The software is designed to be user-friendly and operational on a Windows PC or Mac OS. The mussel farmers’ requirements for this software include entry of the data necessary to support software functions and consideration of the type of paper reports generated that can be used by workers at sea for guidance in their work. The programming is object-oriented so that it is possible to add additional modules.

The software package, accompanied by training for shellfish farmers, is being delivered to the industry in March 2009 for use in the coming production season. In addition a team consisting of a statistician and a shellfish culture expert plan to establish a reliable protocol for sampling shellfish farms in order to evaluate the biomass in production. The results of this sampling will be processed using a computer tool compatible with the shellfish equipment management software in order to incorporate the results.

Duration: Jun ‘08 – Mar ’09 
Funded by: DFO-AIMAP. Co-funded by: MAPAQ, SODIM, Moules Forillon
Project team: Sylvain Lafrance (SODIM), Stéphane Morissette (Moules Forillon), Nathalie Méthot (Gescode), Robert Vaillancourt (SODIM) 
For information contact: Sylvain Lafrance ( sylvain.lafrance@sodim.org
Website: http://www.sodim.org/

Production of oyster spat in a natural environment, Phase 1: tests of cup-collectors

The project tested an adaptation of the French technique, cups, for the collection and production of oyster spat. It is being adapted to the circumstances in New Brunswick in order to mechanize the operation and reduce production costs.

Collection tests were carried out in Bouctouche, NB and Caraquet, NB to evaluate the performance of the new collector. The tests confirmed that the technique improves the productivity of collection and the mechanization of operations. In addition it is making it possible to address key constraints for establishing a sorting strategy that would select the individuals most likely to grow successfully.

Duration: Jul ‘08 – Feb ‘09
Funded by: DFO-AIMAP 
Project team: Léon Lanteigne, Alain Landry, Emmanuel Mallet, Onile Lanteigne, Jules Lanteigne, (all of 638131 NB Inc), Maurice Daigle (Aquaculture Acadienne Ltée)
For information contact: Léon Lanteigne ( Naomie@nbnet.nb.ca)

Algal photo-bioreactor boosts productivity of shellfish hatchery in New Brunswick

The New Brunswick shellfish company, L’Étang Ruisseau Bar Ltd, has selected the northern bay scallop (Argopecten irradians irradians) as a means of diversifying its product base. Research between 2001 and 2005 focusing on improving field production performance led to a protocol that yielded market-size scallops (>52 mm) within one growing season.

The company is currently developing a hatchery-nursery and a wet holding facility in Shippagan, New Brunswick in order to produce bay scallop seed and hold product for the winter sales. This hatchery facility will also be used to implement a genetic improvement program for the American oyster (Crassostrea virginica).

Integrating the Brite-Box, an algal photo-bioreactor, into this facility is key to achieving the desired reliability and economic viability essential to the operation of a commercial hatchery. This development will allow the company to augment their annual revenues by 10-20% and promote the diversification of the New Brunswick shellfish industry.

Duration: Oct ‘08 – Aug ’09
Funded by: DFO-AIMAP. Co-funded by: ACOA, NB DFA, NRC-IRAP, SRD
Project team: André Mallet (L’Étang Ruisseau Bar Ltd), Claire Carver (Carver Marin Consulting), Sylvie Gauvin (L’Étang Ruisseau Bar Ltd) 
For information contact: André Mallet ( amallet@ns.sympatico.ca)

New Brunswick maturation facility for shellfish to be the first of its kind in North America

A multifunctional, closed-loop storage facility for shellfish is in development in New Brunswick, the first of its kind in North America. Taking advantage of new technology developed in France, the project sponsors are building the infrastructure to store shellfish while making it possible to decontaminate the product and maintain the health of coastal areas.

This approach ensures that market supplies are maintained during critical periods in order to take advantage of the globalized market for BeauSoleil oysters. In addition, this project is expected to enable fish regulations to be more flexible while certification ensures the health of the product.

Duration: Aug ‘08 – Mar ’10 
Funded by: DFO-AIMAP. Co-funded by: ACOA, Province of NB, BNB
Project team: Amédée Savoie (Maison Beausoleil), Léon Lanteigne (Maison Beausoleil), Armand Lejeune (EMYG Aquaculture), Brian Blanchard
For information contact: Amédée Savoie ( Amedee@maisonbeausoleil.ca)

Improved hydraulic system helps to automate mussel operations in Newfoundland

Blue mussel seed collection, stripping, grading, and socking operations are the most costly and labour intensive activities on mussel farms in Newfoundland and Labrador. Seeds are handled multiple times and are stored on working platforms for extended periods of time while individual pieces of equipment are installed and removed.

Typically, each piece of equipment has its own hydraulics package to power the equipment. A more efficient new hydraulics system would have the oil capacity to operate multiple hydraulic motors at any given time. This would enable automation of the seeds collection to seeds socking operation and significantly reduce the cost of production for mussel farmers.

Duration: Jul ‘08 – Oct ’08
Funded by: DFO-AIMAP
Project team: Gilbert Simms (LBA Enterprises Ltd), John Pelly Jr. (Western Hydraulics), Scott Simms (LBA Enterprises Ltd).
For information contact: Gilbert Simms Phone: (709) 267-5121, Fax: (709) 267-5121

New Brunswick oyster operation improves biofouling control

Based on the strong results from the first phase in 2007, which evaluated the biological feasibility of using scalding in a boiling water bath to control biofouling, Vienneau Aquaculture sought to establish a procedure to integrate this operation into its oyster-culture activities.

The project was also designed to perfect a scalding system in order to improve the effectiveness of this new approach to controlling biofouling. The results were conclusive but revealed some production constraints related to the silting or deposition of oysters within the culture structures which are currently being addressed.

Duration: Jul ‘08 – Mar ’09 
Funded by: DFO-AIMAP Co-funded by: NBDAA, BNB
Project Team: Paul Vienneau (Vienneau Aquaculture Inc.), Léon Lanteigne (638131 NB Inc.), Alain Landry (638131 NB Inc.)
For information contact: Paul Vienneau ( Tourlou@nb.sympatico.ca)

New blanching technique yields high benefits for Newfoundland IQF mussel products

A Newfoundland project is determining the market acceptance and commercial opportunity of a new blanching technique for whole in shell ready to eat IQF mussels. A pilot scale production line is being set up with Golden Shell Fisheries at their Portugal Cove processing plant.

There are expected to be significant and immediate benefits of this innovative system over the existing vacuum packing system. This technique is reducing production costs while requiring less packaging. It promises greater versatility for producing ready-prepared marketable products such as mussels glazed in beer, wine or natural juices. In addition, there is no restriction on pack sizes for retail or food service and the cooking and freezing container is designed for repeated use.

Duration: Aug ‘08 – Nov ’08
Funded by: DFO-AIMAP. Co-funded by: Newfoundland Organic Seafoods 
Project team: David Walsh, Tom Stephens, Bob Hardy, Pat O’Neill, Eric Coombs
For information contact: David Walsh ( Walsheslogybay@nl.rogers.com)

Newfoundland project makes progress on oyster nursery culture

The Canadian Center for Fisheries Innovation and Badger Bay Mussel Farms are continuing efforts to develop the potential for oyster culture in Newfoundland.

Previous projects have been successful with respect to conditioning and spawning of the oyster broodstock. Fertilization was also successful, although fertilization rates were low and larval survival was poor. During the past projects, protocols have been established for most stages of oyster aquaculture and success has been proven. All these protocols have been developed in stages.

Oysters are a non-native species and are considered incapable of spawning in Newfoundland due to colder water temperatures so seed must be obtained from a hatchery supplier.

In May 2008, 160,000 spat were transferred from the Shippagan Hatchery to the Marine Institute, followed by another shipment of 200,000 spat. The spat were graded and added to upwellers where they were fed until they reached 3 - 5 mm in size.

The goal was to deploy the spat in Placentia Bay for the nursery phase of the project in the late fall. However due to unexpected delays the deployment will now take place in the spring of 2009.

Duration: 2008 – 2009
Funded by: CCFI
Project team: Chris Dawe (MI), Chris Brown (NRC), Marc Kielley (CCFI)
For information contact: Marc Kielley ( marc.kielley@mi.mun.ca)
Website: http://www.ccfi.ca/

Major PEI project develops techniques and strategies to manage invasive tunicates

Aaron Ramsay (Researcher) completing environmental monitoring. (Photo: AVC & PEIAA)

Sustainable and efficient methods of managing invasive tunicate species are needed in the PEI Aquaculture Industry. Invasive tunicates are solitary (Styela clava and Ciona intestinalis) and colonial (Botrylloides violaceus and Botryllus schlosseri).

The PEI Aquaculture Alliance has been collaborating with the University of Prince Edward Island on a four-year Atlantic Innovation Fund project to address the tunicates at three different levels: detection, prevention and treatment.

Monitoring and detection are essential to the management of aquatic invasive species. The detection work proposes to develop a diagnostic kit using tunicate genetic material to identify different tunicate life stages in sea water samples.

The goal of the prevention work is to develop an environmentally sound and sustainable anti-fouling agent derived from marine natural products. Researchers have been analyzing marine samples that do not show any fouling because they may contain a natural product that deters the settlement of tunicate larvae.

The work on different tunicate treatments involves field work and direct collaboration with PEI mussel growers. The efforts include the development of new treatments for the mitigation of tunicates, the delivery of mitigation agents to mussel socks, and the development of lease and bay level mitigation strategies.

Duration: Jun ‘07 – Jun ’11
Funded by: ACOA-AIF. Co-Funded by: PEIAA, UPEI, PEI Atlantic Shrimp Co. Inc., AFRI, PEI-DFARD, DFO
Project team: PEIAA, Russ Kerr (UPEI), Jeff Davidson (UPEI), Ahmed Siah (UPEI)
For information contact: Linda Duncan ( ed@aquaculturepei.com)

Researchers find best algal diet to yield optimum essential fatty acid profile in European oysters

Algal EPA (eicosapentaenoic acid), DHA (docosahexaenoic acid) and ARA (arachidonic acid) are essential in the diet of aquaculture organisms. This project is investigating the type of algal diet that yields the optimum fatty acid profile in European oysters.

Ostrea edulis juveniles were fed with combinations of microalgal diets to determine the effect on growth, survival and fatty acid profiles of these oysters. Juvenile oysters from a shellfish hatchery were laboratory-reared in 15L static tanks with three replicates for each treatment.

The algal combinations tested were: Chaetoceros muelleri and Isochrysis galbana (CHGRA+T.ISO), Tetraselmis striata and Thalassiosira weissfloggii(TETRA+ACTIN), and Nannochloropsis oculata and Pavlova lutheri (NANNO+PAV).

The microalgae were grown in optimum conditions. Fatty acid profiles of algae and juvenile oysters were analyzed. A very highly significant difference (P<0.0001) was found in the growth rate of the oysters. The best growth rate was observed in the NAN+PAV treatment group. The treatment group with lowest growth rate was TETRA+ACTIN. Survival rate was 100% for all treatment groups. EPA, DHA and ARA values were significantly higher in the NANNO+PAV treatment group and lowest in the TETRA+ACTIN treatment group (P<0.001).

Therefore, the best algal diet in culturing European oysters is a mixture of Nannochloropsis oculata and Pavlova lutheri, creating a better growth rate and a higher level of polyunsaturated fatty acids for consumers.

Duration: Sep ‘07 – Sep ’08
Funded by: NSAC.
Project team: Jesse Ronquillo (NSAC), Jamie Fraser (NSAC), Audrie-Jo McConkey (NSAC) 
For information contact: Jesse Ronquillo ( jronquillo@nsac.ca)

Quebec project finds means to reduce mussel depuration costs in Gaspe Bay

Gaspe Bay, an ideal mussel growing area, is subject to periodic contamination, especially after heavy rains. The result is that mussels have to go through a costly depuration process.

Experiments conducted in 2002 showed that using seawater can account for as much as 26% of the total depuration cost at a rate of 50 L/min for 225 kg of bulk mussels, which translates into $0.81 per net kilo. The Canadian Food Inspection Agency currently accepts 40 L/min. Reducing the flow rate could lower these costs.

Trials were conducted in systems supplied with continuously circulating seawater where temperatures varied from 5°C to 8°C in compliance with the Canadian Shellfish Sanitation Program (CSSP) standards governing treatment water quality.

One working hypothesis was that oxygen is more soluble in cold water. Consequently, using a slower water flow rate at these temperatures should not create an oxygen deficit. Two trials were conducted in water at 8°C flowing at 20 L/min and two trials were conducted in water at 5°C (20 and 30 L/min).

Results showed that a flow rate of 20 L/min at temperatures around 8°C in the fall was unacceptable. The CSSP minimum standard for percentage of dissolved oxygen in treatment water could not be met in the water exiting any of these tanks. A flow rate of 30 L/min would be acceptable in 5°C water where dissolved oxygen in those tanks was often higher than 60%.

Duration: Apr ‘06 – Mar ’09
Funded by: DIT-MAPAQ
Project team: Francis Coulombe (CTPA-MAPAQ), Nathalie Moisan (CAMGR-MAPAQ), Michel Girard (CAMGR-MAPAQ), Marcel Roussy (CAMGR-MAPAQ), Cathy Cauvier (CAMGR-MAPAQ)
For information contact: Francis Coulombe ( francis.coulombe@mapaq.gouv.qc.ca)

Sand boxes prove to be ideal for nursery boosting of juvenile clams in Magdalen Islands

Suspended sand-filled box used for softshell clam pre-grow-out on the Magdalen Islands (Photo: M. Déraspe)

Experience acquired on the Magdalen Islands shows that clams must measure at least 25 mm when seeded to obtain the best results. Collected clams measure 8 to 9 mm on average when gathered in the fall. Although they grow somewhat while over-wintering, they still measure only 9 to 10 mm the following spring.

Moreover, a significant percentage of wild clams harvested for transfer to seeding beds are smaller than 25 mm. Consequently, juvenile clam supply strategies call for a pre-grow-out phase prior to seeding.

The MIM program and the aquaculture site ‘Élevage de myes PGS Noël’ have investigated a number of approaches to solve this problem. The most promising is a sand-filled box suspended in the water column in which clams grew twice as fast as clams in the other systems investigated: a FLUPSY and floating bags.

The clams grew as much as 1.04 mm on average per week in the sand-filled boxes, reaching an average size of 25 mm by fall. In addition, 85% to 90% of the young clams were recovered at the end of the growing season.

There are a number of advantages to this approach. The young clams, fossorial bivalves, are placed in optimal growing conditions. Furthermore, the boxes suspended in the water column never emerge from the water so the clams can feed without interruption. Finally, they are sheltered from endo- and epi-benthic predators. All that now remains to be done is to develop this pre-grow-out system for commercial-scale use.

Duration: Apr ‘07 – Mar ’09.
Funded by: DIT-MAPAQ Co-Funded by: CED, MDEIE, SODIM, CLD-Îles-de-la-Madeleine. Project team: Bruno Myrand (CeMIM-MAPAQ), Lise Chevarie (ISMER-UQAR), Réjean Tremblay (ISMER-UQAR) 
For information contact: Bruno Myrand ( bruno.myrand@mapaq.gouv.qc.ca)

Magdalen Islands open-water mussel rearing proves successful

Deployment of collectors by La moule du large inc. 
(Photo : F. Bourque)

A study conducted from 2002 to 2007 to determine the parameters for open water mussel production on the Magdalen Islands (Gulf of St. Lawrence) led the way to the establishment of a commercial mussel production. The chosen site, where the water is 19 m deep, lies 7 km from a fishing harbour.

The results of this study are very encouraging. There were no conflicts between users. No rearing structures were lost throughout the lifespan of the study. Spat collection was abundant and recurrent. Mussels reached commercial size in one year after being socked. Commercial yield exceeded 6 kg/m. Cooked meat yield was greater than 40% even after spawning. Mussels withstood post-harvest treatment well despite having shells about 35% lighter than mussels reared in sheltered environments such as lagoons.

These encouraging results led to the establishment of a new company and since 2007, La moule du large Inc. has been operating a 183-hectare site located next to the experimental site. The first commercially produced mussels are expected to be marketed in 2009.

Duration: Jun ‘02 – Mar ’08 
Funded by: DIT-MAPAQ Co-Funded by: MAPAQ, SODIM, CED
Project team: François Bourque (MAPAQ), Bruno Myrand (CeMIM-MAPAQ)
For information contact: François Bourque ( Francois.bourque@mapaq.gouv.qc.ca)

Research tool is adapted to measure scallop vitality

Maintaining animals in conditions conducive to maximum production and ensuring their survival and growth is essential to success in aquaculture. But the industry lacks simple, quick and affordable operational stress indicators to assess health. So MAPAQ researchers joined forces with their counterparts at Réseau Aquaculture Québec and French Research Institute for Exploration of the Sea (IFREMER) of France to identify simple methods, based on behavioural indicators, which can be used to assess the vitality of sea scallops.

Their work led to the development of a tool that effectively measures scallop vitality. Held in an aquarium supplied with recirculating seawater, a dynamometer measures the muscular strength and reactions of a scallop when it is exposed to a starfish. This technique is used primarily in research projects, and needs to be adapted for use in commercial operations.

MAPAQ and Université Laval researchers are working together to address this need, and ensure the device not only meets the needs of scallop producers but also provides reliable and reproducible data. The main adaptation is the use of a plastic rod to replicate the effect of the star fish on the scallop.

The vitality data has been continuously recorded since 2004 and is identifying the variables to be considered when conducting a simplified analysis. The threshold limit values of these variables for healthy individuals are also being determined. A modified haemostatic clamp is being used to measure the vitality of scallops as small as 10 cm.

Duration: 2004 – 2009
Funded by: DIT-MAPAQ. 
Project team: Madeleine Nadeau (CeMIM-MAPAQ), Xavier Jansoone (UL), Helga Guderley, (UL) 
For information contact: Madeleine Nadeau ( Madeleine.Nadeau@mapaq.gouv.qc.ca)

Finding optimum temperature extends holding time for lobsters in the market

Lobster (Photo: M. Veillet)

What is the best temperature for maintaining live lobster for an extended period while ensuring that meat quality would be acceptable for consumers? Temperature plays an important role in the biological condition of lobsters held for prolonged periods and its effect can be determined by assessing total blood protein levels, and physiological processes like moulting, egg extrusion in females and mortality.

In summer 2007, 157 male and female lobsters were held for an extended period in tanks supplied with seawater. Tanks holding water at 5°C, 10°C and ambient, uncooled temperatures (varying from 11°C to 17°C) were used for the study.

The results confirmed that the health of lobsters is connected to the environmental conditions in which they are held. It is difficult to keep physiological conditions stable at temperatures varying from 11.2°C to 17.4°C. To maintain meat quality, it is advantageous to slow the natural changes that result from prolonged holding.

The optimum temperature seems to be 10°C since relatively high protein levels, which are an indicator of good health in lobster, can be maintained. Little variation is observed in protein concentration, which indicates that physiological processes and stress are fairly well controlled. It also appears that males are the best candidates for prolonged holding since they are not as affected by temperature variations as females. In addition, water taken from the sea at 17°C to 10°C is less costly than cooling it to 5°C.

Duration: May ‘07 – Mar ’09 
Funded by: MAPAQ Co-Funded by: RPPGR
Project team: Nathalie Moisan (MAPAQ), Cathy Cauvier (MAPAQ), Francis Coulombe (CTPA-MAPAQ), Simona Motnikar (CAMGR-MAPAQ), Johanie Cauvier (CAMGR-MAPAQ), Dorothée Mitchell (DFO), Jean Lavallée (UPEI-AVC), Sophie Gauthier-Clerc (ISMER-UQAR)
For information contact: Nathalie Moisan ( Nathalie.moisan@mapaq.gouv.qc.ca)

Quebec project shows probiotics improve scallop larval culture

Photo of an antibiogram, testing the effect of potential probiotic bacteria on the pathogenic bacteria, Vibrios aestuarianus. (Photo: ML Beaudin)

Scallops are cultivated in hatcheries on a commercial scale, but development of the industry has been slowed by massive larval mortality. Researchers have established that opportunistic bacteria in the water are the primary cause of the observed larval mortality. Four genera of bacteria, Pseudomonas,AlteromonasAeromonas and Vibrio, are considered to be responsible for this phenomenon with Vibrio being the most frequently observed.

Solving these problems may lead to the establishment of a more viable commercial industry. The use of antibiotics in larval ponds might improve the situation. However, their use is restricted because of the risks to human health, the emergence of resistant bacteria, and transfers of resistant genes to bacteria that have never been in contact with the antibiotic.

The use of probiotics, defined as a microbial additive with a beneficial effect on the host, could make it possible to prevent diseases in mollusc hatcheries. After testing more than a dozen possible probiotic bacteria, one has been identified to be particularly effective in acting on the four strains of pathogenic bacteria.

Duration: 2007 – 2010
Funded by: MDEIE Co-Funded by: RAQ
Project team: Rejean Tremblay (ISMER-UQAR), Ismail Fliss (UL), Marie-Lou Beaudin (ISMER-UQAR), Bertrand Génard (ISMER-UQAR), Jean-Louis Nicolas (IFREMER-Brest)
For information contact: Rejean Tremblay ( Rejean_tremblay@uqar.qc.ca)

Natural zooplankton-based diet to increase survival rates of lobster larvae

Lobster larva (Photo: ML Beaudin)

Enriching lobster larvae with polyunsaturated fatty acids obtained from a diet of natural zooplankton could improve their survival, and enhance their cryptic behaviour and their flight behaviour when faced with predators’ odours.

Researchers are finding that feed based on natural zooplankton produces a higher accumulation of polyunsaturated fatty acids in the lipid membranes of the larvae. They suggest that this enrichment of the cellular membranes encourages an increased activity of the ionic enzymes that lead to the establishment of osmoregulation.

The osmoregulation process in lobster larvae is established during the transition from the pelagic phase to the benthic phase and can bring about a more rapid installation of the larva on sea bottom, which can lead to improved cryptic behaviour and better chances of surviving predators. To test their hypothesis, the establishment of osmoregulation in larvae fed different diets is being related to various behavioural measurements.

Duration: 2007 – 2009
Funded by: MAPAQ. Co-Funded by: RAQ
Project team: Rejean Tremblay (ISMER-UQAR), Simona Motnikar (CAMGR-MAPAQ), Louise Gendron (DFO), Marie-Lou Beaudin (ISMER-UQAR), Sonia Belvin (MAPAQ-UQAR), Fabrice Pernet (IFREMER-Sète)
For information contact: Rejean Tremblay ( Rejean_tremblay@uqar.qc.ca)

Mussels spat supply may be influenced by plankton fluctuations in the Magdalen Islands

Pediveliger larva of mussels 
(Mytilus edulis) (Photo: N Toupoint)

Work carried out in the lagoons of the Îles-de-la-Madeleine shows some stability in the quantity of organic material present in the water during the larval cycle of the mussels. But recent investigations reveal that the primary diet comes from microzooplankton (small ciliate-type organisms less than 20 µm). Microalgae, on the other hand, only dominate the mussel’s diet on a few occasions over the summer.

Yet, these microalgae are essential for the ontogenic development of the larvae. The microalgae are rich in long-chain polyunsaturated fatty acids while the microzooplankton contain weak-chain monosaturated fatty acids.

Therefore, an overabundance of microzooplankton might be one cause of the slow ontogenic development of mussel larvae. This dietary deficiency in essential elements appears to result in a low rate of successful metamorphosis into juveniles. Thus, poor synchronization of microalgae blooms and mussel larva development might be one cause of the geographic and temporal variations in the harvest success rate.

Researchers in this project are attempting to verify whether variations in mussel harvests in these lagoons may be caused by a mismatch between the larval requirements and the quality of nutrients available.

Duration: 2007 – 2010
Funded by: MAPAQ. Co-Funded by: RAQ.
Project team: Rejean Tremblay (ISMER-UQAR), Nicolas Toupoint (ISMER-MAPAQ), Bruno Myrand (CeMIM-MAPAQ), Frédéric Olivier (CRESCO), Fabrice Pernet (IFREMER-Sète) 
For information contact: Rejean Tremblay ( Rejean_tremblay@uqar.qc.ca)

Hydrodynamic modeling of longlines in Quebec leads to new software program for industry

In 2001, the Regroupement des mariculteurs du Québec (RMQ) commissioned the consulting firm Biorex Inc. to identify possible improvements to the subsurface longlines used to rear shellfish in Quebec and to determine the design criteria for an optimal longline. As part of this contract, a simulation software program was developed to help industry improve the configuration of their subsurface longlines based on rearing site characteristics.

However, it became evident that the main limitation of this software was the lack of accurate data for a number of the parameters used in the model. In addition, this software did not take into consideration the shape of the continuous socks or how sock configuration changes due to current effects.

The accuracy of the simulation results could be significantly improved if more accurate data were available on the environmental characteristics of the rearing sites (particularly current velocity), the submerged mass of the rearing media and the mechanical properties of the various components (drag coefficient due to fouling, tensile strength of the anchors and elasticity of the ropes).

A second contract was therefore awarded to Biorex Inc. with the general objective of conducting new numerical simulations using more accurate data for the modelling parameters. Several surveys were carried out by the team of consultants to characterize in detail the longlines, currents and waves as well as the hydrodynamics at the main mariculture sites, the strength of the various types of anchors and, finally, the strength of the ropes used. A separate characterization report was prepared for each of these parameters.

The requirements also included developing a new software program, in collaboration with the National Research Council of Canada (NRC). The final version of this software was delivered to SODIM in June 2008. A copy of the NRC software program is available in each of the three mariculture regions in Quebec through frontline technical support officers.

Duration: Sep ‘05 – Aug ’08 
Funded by: SODIM. Co-funded by: MAPAQ, MDEIE
Project team: Robert Vaillancourt (SODIM), Pierre Bergeron (Biorex Inc.)
For information contact: Robert Vaillancourt ( Robert.vaillancourt@sodim.org)

Quebec research assesses ecological risk of spat transfers

The risk of transfer of undesirable species potentially associated with transferred spat is currently the main reason for DFO’s refusal to allow transfers in Quebec. However, security of the spat supply continues to be a critical factor for Quebec mariculture operations and sometimes depends directly on the approval of transfer requests.

Better knowledge of the ecological risk associated with these transfers and field protocols designed to minimize the risk of introduction of undesirable species from spat supply sites would help minimize the risk posed by these transfers. It is therefore critical that the industry have as much information as possible on this subject in order to develop field protocols that would be considered satisfactory in the context of the DFO risk assessment process in the event that undesirable species are present at a supply site chosen by the industry.

The objective of this study is to identify and more effectively assess the ecological health risks associated with transfers of wild spat from mussels, sea scallops and clams and to propose methods for mitigating this risk.

Duration: Apr ’07 – Mar ‘08
Funded by: DFO-ACRDP. Co-funded by: SODIM, UQAR-ISMER, 
Project team: Chris McKindsey (DFO)
For information contact: Chris McKindsey ( Chris.McKindsey@dfo-mpo.gc.ca)

PEI project delves into invasive tunicate biology to improve management

Since the establishment of invasive tunicate species in Prince Edward Island (PEI) waters, Styela clava and Ciona intestinalis have had devastating effects on mussel culture. Mussel productivity has been adversely affected by these infestations and this is posing challenges for farm husbandry.

This project is exploring some aspects of tunicate biology which could be exploited to minimize tunicate abundance in aquaculture sites through passive approaches. The first objective is to investigate the reproductive biology of C. intestinalis in PEI waters with the aim of determining the optimal time and effort of active treatment. The second objective is to evaluate environmental tolerances of tunicate early-life stages in order to determine their level of vulnerability to natural and/or treatment conditions. The third objective is to document the effects of water flow on the recruitment ability of C. intestinalis.

Duration: Apr ‘08 – Mar ‘11
Funded by: DFO-ACRDP. Co-funded by: PEIAA, PEI DFAE
Project team: Daniel Bourque (DFO)
For information contact: Daniel Bourque ( Daniel.Bourque@dfo-mpo.gc.ca)

Researchers work to improve quality of hatchery-reared lobster larvae

The decline of lobster (Homarus americanus) landings in the southwestern Gulf of St. Lawrence (swGSL) has led some fishers’ groups to develop larval or juvenile lobster release programs to complement existing conservation measures. However, there is no point in producing Stage IV lobster larvae if they cannot survive in the natural environment after being released.

To address this problem and achieve its Stage IV lobster production objectives, Homarus Inc. (a branch of the Maritime Fishermen’s Union) established a research partnership with the Coastal Zones Research Institute (CZRI) in April 2002.

While the zootechnical aspects have now been mastered, the nutritional aspect remains problematic. The primary objective is to find an appropriate alternative to live feed production, which entails very high labour costs. Larval lobster production relies heavily on the use of live feed (brine shrimp). However, live feed production can account for up to 50% of hatchery operating costs during the first few months of production. This factor limits the commercial production of many marine species, including lobster.

Stage IV is a critical stage for lobster, because the larva is transitioning from a pelagic to benthic lifestyle. Good physiological conditions, combined with appropriate lipid reserves, will give the larva a certain advantage for adapting to its new lifestyle. These indices have never been developed in larval H. americanus and are key to the advancement of research into the production of high-quality larvae with a good chance of successful release into the natural environment.

Duration: 2004 – 2010
Funded by: Homarus Inc., NRC-IRAP. Co-funded by: NBIF,NB DAA –Total Development Fund
Project team: Dounia Daoud (CZRI), Rémy Haché (CZRI), Yves Hébert (CZRI), Claude Landry (CZRI), Caroline Roussel (CZRI), Steven Mallet (CZRI), Rémy Benoit, Martin Mallet (Homarus Inc.), Michel Comeau (DFO), Sébastien Plante (UMonctonSC), Gilles Miron (U Moncton)
For information contact: Dounia Daoud ( Dounia.daoud@irzc.umcs.ca)
Website: www.irzc.umcs.ca

Project seeks alternatives to live algae for American oyster larvae production

Larval production techniques in American oyster (Crassostrea virginica) hatcheries have now been mastered. Rates of survival, growth, metamorphosis and particularly larval attachment vary depending on the quality of the diet. An appropriate diet therefore allows larvae to better tolerate production conditions and to build up sufficient energy reserves to undergo the critical stage of metamorphosis, during which the larvae attach to a substrate.

Hatcheries currently produce their own live algae. Algae production is costly, particularly in terms of labour. This project is focused on completely or partially replacing live algae produced in hatcheries with commercial alternatives: dried algae powder and algae concentrates. Since American oyster is a highly selective feeder, the challenge in this project is to find a high-quality alternative food that is adapted to this species.

After much testing, our preliminary results are encouraging. They indicate that it will be possible to reduce algae production in hatcheries by at least 50% over the medium term.

The overall objective of this project is first to reduce production costs in order to increase the economic viability of the hatcheries while maintaining the quality of the product. The second aim is to promote the development of oyster hatcheries in eastern Canada.

Duration: 2008 – 2009
Funded by: CZRI
Project team: Florent Garnerot (CZRI), Chantal Gionet (CZRI) 
For information contact: Florent Garnerot ( florent.garnerot@umcs.ca)