Tunicate Treatment Systems for Mussel Aquaculture on PEI

FINAL REPORT
Reporting Period: April 20, 2009 to March 31, 2010

Report to the Department of Fisheries and Oceans – AIMAP Program (Aquaculture and Innovation Market Access Program)

Submitted by the Prince Edward Island Aquaculture Alliance
March 31, 2010

The Development and Early Commercialization of Four Innovative Tunicate Treatment Systems for Mussel Aquaculture on PEI

AIMAP Project 2009-G15

A. Project Background

This one year, multi-component project developed and assessed equipment designed to mitigate the impact of solitary and colonial tunicates on the co-applicants’ mussel aquaculture farms. The main objectives of this industry-led project were to:

• Develop for the first time, mitigation equipment specifically for colonial tunicates
• Design treatment systems that address multiple species and the need for multiple treatments  on the same farm or estuary, and
• Bring further development to existing equipment with the purpose of early commercialization.

This project addressed the following technical gaps identified by industry and researchers in the area of tunicate treatments:

• The lack of standardized technical drawings
• The lack of ability to be flexible and versatile when treating multiple species
• Absence of a system to treat colonial tunicates
• A method to treat underwater, hence without lifting the line (reduction of mussel fall-off)
• Current equipment does not necessarily meet safety and stability requirements

The final deliverable of this project included technical drawings of newly developed equipment for the mitigation of tunicate infestations. The provision of standardized technical drawings can be used by mussel growers to improve or build new systems. It is expected that these drawings will assist the grower in purchasing and building equipment by providing a base for the construction of the equipment. This will provide the industry with innovative, economical, efficient, safe and environmentally sustainable methods to mitigate tunicates.

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B. Project Components

1. Project Administration – Prince Edward Island Aquaculture Alliance

The Prince Edward Island Aquaculture Alliance (PEIAA) administered this one year project. Project notification was received from DFO-Aquaculture Management Division (AMD) on April 20, 2009. The PEIAA attended an initial project meeting with DFO-AMD (Stephen Langteine, Florence Albert and Josiane Massiera) on May 7, 2009 in Charlottetown, PEI. On July 27-28th Florence Albert travelled to PEI to meet with the five growers involved in the project: Jason Simpson, Stephen Fortune, Carl Reynolds, Hal Publicover and Wayne Chiasson. The Contribution Agreement was signed during these meetings. The advance payment from DFO-AMD was received on September 1, 2009. A meeting on May 5th was held with the PEIAA and growers involved to review the project, finances and logistics.

During the week of May 15th, the PEIAA and Fundy Engineering met with the growers involved in the project to review conceptual ideas for each machine.

Project Steering Committee Meetings
Steering Committee meetings took place on a monthly basis for the duration of the project. The first Project Steering Committee meeting was held on October 2, 2009. The Steering Committee is comprised of representatives from the PEI Aquaculture Alliance, PEI Department of Fisheries, Aquaculture and Rural Development, Fisheries and Oceans Canada (DFO – PEI), Fundy Engineering and growers. At the first meeting growers provided updates on their projects with feedback from Committee members. Discussion was held on project time lines, possible need for a project extension and engineering work being completed. At subsequent meetings, the group discussed progress made on the fabrication of the machines. The final two meetings held provided the opportunity for the group to finalize timelines around fabrication and the development of technical as-built drawings.

2. Projects

a) Development and Assessment of an Underwater Spray Unit to Treat Colonial Tunicates (Mr. Jason Simpson)

A smaller, lower pressure system is required for the colonial tunicates (Golden Star and Violet) as compared to the equipment designed for the solitary Vase tunicate. In previous work, there have been challenges in producing underwater washing equipment with enough force to remove the solitary vase tunicate; however, it is anticipated that the more loosely attached colonial tunicates will be removed by pressures delivered with the underwater system. To date, no prototype for the development of equipment to treat colonial tunicates has been developed.

Phase I – Research and Design

Research on the spray head concept and nozzle/water flow calculations were completed during the month of August and September by Fundy Engineering and Jason Simpson. Peter McKelvey and Trevor Richard (Fundy Engineering) met with Jason Simpson on August 11th to discuss design and to conduct a site visit to review boat measurements and requirements.

Conceptual drawings for the low pressure spray system were provided to Jason Simpson on August 24th for his review. As a follow-up to this, Trevor Richard met with Jason Simpson and his machine fabricator, Kent Clark of Kent Clark Welding and Machine Limited in Indian River PEI on September 24, 2009. From this meeting, follow-up research on differences between nozzles and slots for water flow were examined, i.e. pressure requirement, flow parameters and impact of the spray on the mussel sock. Mr. Simpson consulted with mussel growers regarding the underwater concept and pressure sprayers.

Indicators of Success for Phase I

Research was completed on the underwater spray head concept and different nozzle calculations were completed for the development of the system. Water flow and power calculations provided information for the type of pump required, the size of the nozzles and/or slots for the sprayer. Technical drawings were completed. It is important to note that as construction took place, the technical drawings were reviewed and revised.

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Phase II – Construction and Testing

Updated drawings and a Bill of Materials were sent to Jason Simpson by Trevor Richard of Fundy Engineering on October 8th. In this package specifications for a pump were also included. Kent Clarke of Kent Clarke Welding and Machines Limited reviewed the pump suggestions to confirm that the pump would function in a marine environment pumping salt water. Pipe measurements were provided by the engineers to Kent Clark. During the months of November to January fabrication on the machine took place with the development of the power base of the sprayer and the spray box. Issues were initially encountered with the delivery of the pump. However the pump arrived in time to be linked to the spray system.

As discussed under Phase I, fabrication of the spray system took place at Kent Clark Welding. Supplies and equipment were ordered locally and from Atlantic Canada. Through various consultations with Scott McNevan from East Coast Engines, Kent Clark, Fundy Engineering and Jason Simpson different machine specifications and design ideas were discussed. Mr. McNevan, and Mr. Clark provided significant technical and logistical advice around pump and machine specifications, materials ordered and machine design. It was important to see this collaboration between the grower and fabricator/suppliers since the aquaculture industry relies heavily on local fabrication shops to build and modify existing treatment equipment.

The spray system constructed from aluminum and stainless steel is powered by a 75 hp (horsepower) Deutz diesel oil-cooled engine. The oil cooling system omits the need for a fan and radiator which can become corroded over time. The sprayer is a versatile piece of equipment which can operate from 2 positions on a mussel boat depending on spraying requirements. The main components of the sprayer are four pipes with fifty-four 0.75 inch laser cut slots for water flow. The slots are 0.75 inches apart on the pipes. The pipes have two different flow rates: two pipes with 30 ml and two pipes with 20 ml. The sprayer’s pump is versatile as it can be used from a low 40 to 50 psi up to 150 psi (pounds per square inch) with up to 1000 gallons per minute.

Versatility of treatment methods is a key feature of this sprayer. The slotted pipes are adjustable through their upwards and downwards movement. The sprayer can be used both above water and underwater. The height of the pipes can be adjusted allowing the growers to raise the mussel socks out of the water at different heights. For example, in the underwater application, the pipes would be completely submerged and for above water, based on pipe height, the entire sock or a portion of a sock can be treated. If a portion of the sock is treated above water, the lower portion of the sock can be treated with the other pipes underwater. Depending on the grower’s requirements and the level of infestation, two or four pipes can be used for treatment. The water pressure and volume, the most significant parts of this machine, have a wide operating spectrum to accommodate various levels of infestation on various stages of mussel socks.  Water from the sprayer is deflected from the boat through the use of a deflection shield.

It should be noted that previously the grower used a hand held hose to spray the tunicates off the mussel socks. This process was both time consuming and lacking in consistency in treatments per sock depending on the distance of the spray from the hose to the mussel sock. It is challenging to maintain the large mussel crop through the use of hand held methods. Mussel sock yields were decreased but labour and time were increasing steadily as the infestation levels grew and evolved over the season. It is hoped that with the development of the current spray system, the grower will be able to go over his entire crop in a span of one week instead of the previous three to four weeks required. With the mechanized treatment of the mussel socks, the grower is also hoping to increase safety on the boat because the workers will be not be leaning over the side of the boat to treat the mussel socks. The grower is also hoping that the sprayer will increase byssal thread attachment resulting in mussels that are tightly bound in the sock thereby reducing mussel fall-off during treatment.

Field testing of the project will take place during the summer of 2010 (tunicate season) with the aquaculture staff of the provincial fisheries department. An addendum to the final report will be submitted following the field testing and analysis of results.

Indicators of Success for Phase II

A suitable manufacturer (Kent Clark Welding) was hired to complete the spray system. The equipment was built on time, to the required specifications and at the cost of the original quote. As noted in the section above, field testing will take place in the summer of 2010. The boat is currently in winter storage at the welding shop in preparation for the field season.

Please refer to Annex #1 – Underwater Spray Unit as-built drawings.

b) Development and Assessment of an Above Water Spray Unit to Treat Colonial Tunicates and a Conveyor System to Collect Biomass Removed (Mr. Stephen Fortune)

The proponent for this project has experimented with a small single nozzle high pressure sprayer to remove tunicates from his crop. This technique was successful in removing tunicates and increasing mussel attachment. This process is time consuming and labour intensive. In order to adequately and efficiently treat colonial tunicate fouled socks a new automated system must be produced, efficient enough to treat a minimum of 20 lines per day.

Phase I – Research and Design

Fundy Engineering conducted a site visit with Stephen Fortune on August 11th to review design concepts and mussel boats. Conceptual drawings of the variable pressure spray system were submitted to Mr. Fortune on August 28th. The conceptual design estimated that the system would have reduced weight and increased maneuverability required due to the suspension of the system on the mussel boat.

On September 15th, follow-up conceptual designs including the biomass conveyor collection system were provided to Mr. Fortune. Grandview Welding Limited in Vernon Bridge, PEI was selected as the fabricator for this project.

Indicators of success for Phase I

Previous research on high pressure sprayers (completed on another project) was reviewed by the engineers. The grower and fabricator reviewed different nozzles for the spray system. Conceptual drawings were provided to the grower and fabricator for their review. It is important to note that as construction progresses, changes and revisions were made to the design and equipment specifications.

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Phase II – Construction and Testing

As indicated in Phase I, Grandview Welding was selected as the fabricator for this system. Other local suppliers (e.g. Hydraulic Power Plus) also provided additional materials and equipment. Updated drawings and a Bill of Materials were sent to Stephen Fortune by Trevor Richard on October 8th. Mr. Fortune and the fabricator reviewed the drawings and Bill of Materials with the fabricator making suggestions and changes for the materials and the overall design.  

Using materials and equipment described in Phase I, a spray system for colonial tunicates was constructed. The spray system’s power supply is equipped with a transmission where the ratio can be changed (1200 rpm to 800 rpm) which eliminates the need for extra pumps and belts. Two rows of nozzles (8 per side) were included in the spray box. These nozzles can rotate and move upwards and downwards to facilitate increased coverage by the water spray on the mussel socks. Fabrication on the spray box (power head) was completed in December 2009. Mr. Fortune has installed the power head on his boat’s boom to test the fit.

In the development and design of the sprayer, the grower wanted to see a machine that was portable. With portability, any boat can pick up the spray box (power head) if a boom is present on the boat. In addition to being portable, it is hoped that the current spray box will provide added versatility to the mussel grower by allowing flexible use of the boat. The boat using this spray box does not have to be committed to treating mussel socks solely, it can harvest at any time. The spray box can be brought to the wharf at any time and the boat can start to harvest. Due to the compact design, the resulting deck space can also be used for purposes other than tunicate treatment. The main diesel engine is used to power the pumps for the sprayer; therefore, no extra engine or gear is required.

In addition to the features described above, increased coverage of the mussel sock by the spray is expected due to the machine’s ability to off-set the holding point for the mussel sock allowing the spray box to be angled. By angling the box, the spray can cover the lower portion of the sock that is often missed during tunicate treatment.

Field testing of the project will take place during the summer of 2010 (tunicate season) with the aquaculture staff of the provincial fisheries department. An addendum to the final report will be submitted following the field testing and analysis of results.

Indicators of Success for Phase II

Grandview Welding was selected as the fabricator of the spray system. Budget and scheduling requirements have been met for the construction of the equipment. Mr. Fortune has used his boat’s boom to mount the equipment. The spray box has been fitted to the boat and boom. As indicated above, field testing will take place during the summer of 2010.

Figure 3 and Figure 4: Above Water Spray Unit to Treat Colonial Tunicates and a Conveyor System to Collect Biomass Removed
Please refer to Annex #2 – Colonial Above Water Spray Unit as-built drawings.

c) High Pressure Water Treatment System (Mr. Hal Publicover and Mr. Wayne Chiasson)

To date there have been a variety of high pressure systems produced for the treatment and removal of the solitary vase tunicate fouling mussel socks and gear. Engineering assessments have been conducted on a variety of the systems and growers now have considerable experience in utilizing these systems. Growers and engineers have suggested improvements to these systems which will be included in detailed technical drawings for the equipment produced under this project. In developing this project, the proponents wanted to build an improved machine which provided increased coverage on the tunicates and increased safety for workers on the mussel boats.

Phase I – Research and Design

Fundy Engineering conducted a site visit on July 13th with Mr. Publicover and Mr. Chiasson. The fabricator of the high pressure spray system was selected to be Quinn’s Marine Machine Shop in Cardigan, PEI. A preliminary conceptual drawing was forwarded to the growers on July 22nd. On August 11th, Fundy Engineers and the growers visited Quinn’s to discuss the design concept with equipment and materials being ordered at this time. The proposed design has had two main changes from previous designs: the machine has an additional row of nozzles for increased coverage and an adjustable hauler (starwheel) that moves upwards and downwards which guides mussel lines with socks out of the water and through the spray system.

Indicators of Success – Phase I

Components have been sourced within budget for this machine.

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Phase II – Construction and Testing

On October 15th, the PEI Aquaculture Alliance met with Wayne Chiasson at Quinn’s Marine Machine Shop to discuss progress on fabrication.

Two main features of this machine:

• i) A movable hauler powered by two (2) hydraulic cylinders is provided to aid in the lifting of the backline. A moveable hauler allows for bottom coverage of the mussel sock which was not on the previous machine. Also by having a movable hauler there is increased safety for lifting the backline and reduced treatment times per day by reducing the time required for lifting each backline.

• ii) Two rows of 8 oscillating nozzles per side for a total of 32 nozzles. The increased number of nozzles (rows specifically) is intended to decrease treatment time by allowing the boat to travel at a faster rate.

The sprayer was completed on November 10th. The PEI Aquaculture Alliance travelled to Georgetown/Cardigan to view the sprayer during it first trial run on November 12th. Representatives from the PEI Department of Fisheries, Aquaculture and Rural Development collected mussel sock sections for preliminary pre-treatment field tests on November 12th and post-treatments tests on November 24th.  Fundy Engineering completed As-Built Drawings including a materials list for the spray system.

Preliminary Grower Feedback
During the development of this project, discussions with Mr. Publicover and Mr. Chiasson centered on safety issues with lifting the backline and increasing coverage of the mussel sock by the spray system. They wanted to see a machine designed with a hauler that moves up and down to assist with bringing up the mussel lines and providing increased coverage.  From a growing perspective a movable hauler provides the following benefits:

• Full extension for lifting and moving the backline
• Increased head room and ease for hook-up and un-hooking of the backline
• Increased speed and efficiency – increase the number of lines of mussels that can be treated per day
• Strain is eased on lifting the backline for safety considerations

In addition to the movable hauler, increasing the number of rows of nozzles from one to two on each side of the sprayer provides the following benefits:

• Spinning of mussel sock as it travels through the spray system is reduced
• Exposure time of spray to attached tunicates is doubled

Indicators of Success – Phase II

As indicated previously, Quinn’s Marine Machine Shop was selected as the fabricator of the machine. The equipment was built on time, to the required specifications and at the cost of the original quote. The equipment has been mounted on the growers’ boat with field testing (pre-and post-testing) completed in November 2009. Tunicates were removed and as discussed under preliminary grower feedback, treatment times were reduced.

Phase III - Modifications

Biological Evaluation of Technology (Submitted by Aaron Ramsay, PEI Department of Fisheries, Aquaculture and Rural Development (DFARD))
Staff from DFARD met with Wayne Chiasson and Hal Publicover in Cardigan River on November 12, 2009 to observe their machinery in operation and to collect samples for the purpose of determining effectiveness of the technology in reducing the biomass of Ciona intestinalis on mussel socks.

Socks on one mussel line were treated with the equipment and five socks were collected for laboratory analysis. An additional 5 control socks were collected from a neighbouring line that had not been treated. Each sock was cut into three 30 cm sections and the following parameters were measured: (1) tunicate weight (2) mussel weight (3) mussel density and (4) average mussel length. The most relevant measurements are tunicate weight and mussel weight to determine if the machinery is reducing the tunicate biomass without causing fall-off of mussels. The tunicate weight may not be entirely representative of the efficiency of the equipment immediately after treatment, as some tunicates may have been killed, but remain on the sock. A follow-up sampling was completed on November 24th. Five 30 cm sock sections were collected from five different socks that had been treated on November 12th.

The analysis by DFARD showed that there was a major reduction in tunicate biomass on the mussel socks from the treatment. Prior to being treated there was approximately 175 g of tunicates on 30 cm of mussel sock. This mass was immediately reduced by 50% following the treatment. The follow-up analysis 12 days later provided evidence for an additional 40% reduction in tunicate biomass for a total of 90% reduction in tunicate biomass on the mussel socks following the treatment. The weight of mussels in a 30 cm section of sock did not significantly decrease after the treatment was applied.  

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Indicators of Success – Phase III

As indicated in the previous section, successful field tests were completed on the machine. The requirement for follow-up field tests in the summer of 2010 will be discussed with provincial aquaculture staff and the growers in the spring of 2010.

Please refer to Annex #3 – High Pressure Spray System as-built drawings.

d) Comprehensive delivery system for tunicate treatment equipment (Carl Reynolds)

Mussel growers with multiple species of tunicates fouling their farms require a variety of types of treatment equipment for the different species and for the different stages in the life cycle of the tunicates. In this project, the component developed a stabilizing system to attach treatment equipment to the boat and distribute the weight over a wider area.

Phase I – Research and Design

Mr. Reynolds designed and developed a prototype for an equipment platform for treating multiple tunicate species. Equipment used for different treatments that were to be mounted to this platform were reviewed and specifications taken into consideration for the design of the platform. 

Indicators of Success for Phase I

Mr. Reynolds incorporated the specifications of existing equipment into the overall design of the treatment platform. As indicated above, the delivery system was designed by Mr. Reynolds using his background in engineering and in aquaculture equipment design. Conceptual drawings were completed by Mr. Reynolds. It was determined that Fundy Engineering would complete the final as-built drawings of the treatment platform.

Phase II – Construction and Testing

Due to size and logistics around the equipment, welding took place at on-site facilities operated by Mr. Reynolds. Suppliers were sourced locally and in Atlantic Canada for equipment, supplies and materials. The overall design and construction resulted in a work platform in the form of a catamaran with the primary use of tunicate treatments. The equipment currently in use on Island mussel farms can be installed and used on this platform. This equipment includes:

• Spray systems (e.g. high pressure sprayers)
• Brush machine
• Lime trough

The design allows for flexibility, versatility and efficiency in treating tunicates using the platform. It will be simpler and safer to use this platform dedicated to treatment instead of working off the side of the boat. The treatment system consists of two aluminum pontoons (40 ft long, 6 ft wide and 3 ft deep). The pontoons are held together by an overhead beam and post between each pontoon. The pontoons are 11 ft apart. The platform is equipped with the following components:

• One bow and one stern thruster
• Hydraulic equipment for handling lines
• Hydraulic winch to handle equipment
• Power provided by a 75 horsepower diesel engine with a double hydraulic pump to run thrusters and a triple hydraulic pump to run haulers and other equipment

Field testing of the project will take place during the summer of 2010 (tunicate season) with the aquaculture staff of the provincial fisheries department. An addendum to the final report will be submitted following the field testing and analysis of results.

Indicators of Success – Phase II

Mr. Reynolds has taken his experience in equipment design and fabrication to build the current treatment platform. Mr. Reynolds has the equipment, crew and facility to complete welding and cutting of the aluminum and for the main fabrication. Equipment was built to fit in with the current project year, to the required specifications and at the cost of the original quote. It should be noted that due to Mr. Reynolds completing the engineering work, funds from the engineering budget were re-allocated to the cost of fabrication. Treatment equipment will be mounted to the platform prior to the field testing taking place in the summer of 2010.

It is expected that this delivery system will provide growers with increased stability while on the water maintaining their mussel crop. This system will also allow the grower to move from one treatment type to another to respond to the different tunicates on their mussel leases.

Mussel growers have to increase efficiency of treatments and the time taken to complete the treatments. As a result of tunicates and the problems with tunicates, production has been reduced by approximately 60% because growers and their farms can not handle current infestations of crop. With new equipment it is estimated that production can return to previous levels.

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3. As-Built Drawings

The different tunicate treatment systems developed and constructed under this AIMAP project demonstrate the innovation of Island mussel growers. To share the knowledge gained and the equipment developed in this project, as-built drawings were developed by Fundy Engineering with significant input and feedback from the growers and fabricators involved. Numerous revisions and drafts of the drawings were completed. It was decided by the Project Steering Committee that in order to ensure that the drawings will be beneficial to the aquaculture industry, each drawing was reviewed and assessed by the fabricators involved in the project to provide validation using the following guidelines:

• Are the drawings readable?
• Based on the drawings and the specifications provided, can a machine be built?
• Can a fabricator provide a quote for the fabrication of the machine based on the drawings?

Fabricators reviewed the drawings of their machines and those of the other projects.

4. Conclusion

The original objectives of this project were to develop equipment for colonial tunicates and to develop a platform to treat multiple species of tunicates. The final project objective was to further develop existing tunicate treatment equipment and bring to a pre-commercialization phase with standardized drawings. Overall, the objectives of the project were met. Two innovative treatment systems for colonial tunicates were developed using above water and under water treatment technology. The high pressure sprayer currently in use to treat solitary tunicates was developed further through the use of novel nozzle configurations and increased safety features. A comprehensive tunicate delivery system was developed to assist growers that have to treat multiple species of tunicate on their mussel leases.

By providing standardized and validated as-built drawings of each of these treatment systems, Island mussel growers will have a base for the construction of new systems. These drawings will assist growers with communicating their needs to equipment fabricators and developing new ideas for their systems.

Field testing of the equipment will take place in the summer of 2010 which spans the tunicate season. Assistance in the field testing will be provided by provincial aquaculture staff. An addendum to the final report will then be submitted with field testing results. 

5. Acknowledgements

The project proponents would like to thank the following project partners for their support and funding:

• Fisheries and Oceans Canada
• Atlantic Canada Opportunities Agency
• PEI Department of Fisheries, Aquaculture and Rural Development

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