Innovative Sustainable Solutions for Canadian Finfish Aquaculture Operations: Continuation of AEG Feeder Pulse vs. Meal Feeding with Aquasonar Integration Evaluation
Final Report

Aquaculture Engineering Group Inc. (AEG)
AIMAP-2009-M02

Project Title
Innovative Sustainable Solutions for Canadian Finfish Aquaculture Operations: Phase II

Project Summary
AEG Inc. was incorporated in November 2002 to develop equipment and management solutions that meet existing technology shortcomings. This AIMAP project allowed the first integration of the advanced AEG Feeder and AEG Containment Systems while including fish on a commercial very high-energy grow-out site in St. Mary’s Bay, NS. Trout were stocked within the deployed AEG Containment Systems in October-December 2009. Initial mortality was quite high due to saltwater tolerance issues but ~ 200,000 fish remained to complete project activities. The mortality rate eventually settled to below the target 0.6% per month despite being on a very high energy site. Pulse feeding provided acceptable results with an overall site FCR under 1.2. Fish growth was initially projected to reach the target harvest weight by August 2010 but feed belching unexpectedly occurred in July 2010. At this time feed provision was reduced to control feed belching but growth was sacrificed extending the time to reach the target harvest weight of 2.15 kg to November 2010. In total, more than 130,000 lbs were processed as dressed head-on product and upwards of 200,000 lbs of fillets were produced from the site. These fillets were very consistent in quality characteristics such as firmness, shape, size, gaping and color. The submersible collar developed in Phase I proved invaluable as the cages needed to be submerged in February 2010 to avoid ice flowing through the site. Integration of the AquaSonar automatic fish sizing technology provided encouraging results although significant issues must be addressed before commercialization is possible. The financial benefits associated with use of AEG Solutions are substantial with more than $800,000 additional profit possible when all benefits are compiled and compared with raising commercial volumes using traditional systems and methods.

Project Rationale and Objectives
For 12 years, AEG proponents operated a very successful commercial Atlantic salmon aquaculture company in the Bay of Fundy region that produced 5,000 metric tonnes annually until the company was sold in 2003. This extensive experience of actively raising fish in sea cages provided AEG with a solid understanding of the technological and management limitations presently experienced by the global finfish aquaculture sector. In response, AEG was incorporated in November 2002 to develop innovative solutions – AEG Solutions – to address limitations impeding further sustainable growth of the finfish aquaculture industry worldwide.

AEG Solutions was originally designed for use predominately in high-energy open ocean environments. To this end, individual products have been professionally engineered and model tested at the National Research Council Institute for Ocean Technology in St. John’s, NL in simulated high-energy conditions prior to fabrication and field-testing of commercial-scale prototypes.

• The AEG Feeder is designed to provide water-borne delivery of feed thereby maintaining the feed delivery pipes below the active ocean surface. The AEG Feeder is capable of ‘meal feeding’ cages similar to all other centralized feeders available globally or using feed boats but also the onboard hydraulic/PLC system control is now programmable to also provide ‘pulse feeding’ capability whereby up to 28 cages can be fed simultaneously. Use of the pulse feeding strategy had never been tested in a commercial setting prior to this project.
  
• AEG Containment Systems combines surface logistics strategies common in the aquaculture industry with subsurface mooring connections that are increasingly integrated in novel ‘offshore’ cage designs. The AEG Containment System has been developed through several iterations prior to the start of this AIMAP project but never evaluated to raise fish.
• AEG had developed an advanced site data management software program – Neptune – but debugging this application with real site data had not been completed before this AIMAP project. Furthermore, Neptune has one module capable of continually predicting fish size over time and the eventual harvest date based on a feed rate and assumed FCR. The full potential of this program will be realized when measured fish sizing data can also be automatically imported and compared with predicted fish sizes over time. These comparisons could allow feed rate adjustments to maintain anticipated harvest schedules to meet market demands. Further, ongoing collection of fish size data coupled with measured feed provision data will allow continuous calculation of FCR and therefore better feed management and reduced environmental impact. This AIMAP project allowed proof-of-concept evaluation of integrating an automatic fish sizing technology.
• This project site experiences very high energy – 70 knot winds, 4 m waves and 1.8 knot currents – on a fairly regular basis. The site also receives ice flows in February that has inflicted severe site damage and fish loss on more than one occasion in the past. AEG used this AIMAP project to develop a proof-of-concept submersible HDPE collar to avoid the ice flow and other surface based perils.
  
• AEG Solutions as described has never been fully integrated on a single commercial aquaculture site for performance evaluation and monitoring while raising a stock of fish. This specific AIMAP project enabled AEG to complete this necessary integration step within a commercial scale operation to raise fish at a commercial stocking density. Operating AEG Solutions in an integrated manner also allowed development of additional logistics mitigation strategies as necessary to ensure cost-effective operations are possible.

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Location of the Project
AEG subleased finfish aquaculture site #1012 in St. Mary’s Bay, NS was used to complete the activities of this AIMAP project. The site offered many challenging attributes that  demonstrated the full potential of AEG Solutions to raise fish in higher than normal energy. The site also represented an excellent opportunity given the size of the site (19.5 ha), the continuously flushing current to oxygenate contained fish and clear farm wastes, the relative isolation from other aquaculture operators and an excellent water temperature profile to raise salmonids.

Aquaculture Site #1012 is located near Tiddville north of Petite Passage along the southeastern shore of Digby Neck. The nearest wharf for site maintenance is 3.22 km northeast of the site in Little River. AEG pays regular wharfage fees in Little River but also in Sandy Cove, which is located further north but has greater wharf capacity to hold vessels especially during storms.

The site is close to shore and protected in the general N-NW direction. However, this is the extent of protection on this site with very long fetches present from the NE (up St. Mary’s Bay) and SE-S-SW (mid-Atlantic exposure) directions. Additional care must be taken to moor any aquaculture infrastructure on the site as the wind can occur for prolonged periods of time and the resulting waves can be severe and damaging. The current on the site regularly moves at 1.5 knots while higher running tides can reach 1.8 knots.

Site Set-up & Fish Entry
More than 300,000 trout were delivered to the site in Fall 2009. The initial entry in October 2009 experienced a higher than anticipated mortality rate following saltwater entry for steelhead trout. This resulted in delaying the entry of the majority of the trout and the application of SuperSmolt in an attempt to increase saltwater survival. This effort did not work and total entry mortality was upwards of 35% leaving approximately just 200,000 trout for continued grow-out on the site. This mortality rate was significantly higher than anticipated for the trout strain assured for delivery to the full salinity grow-out site indicating that the proper strain of trout was not entirely delivered to the site for grow-out to market size.

Technology Performance
Modern finfish farming, currently utilized in Canadian waters to raise Atlantic salmon, began a little over 35 years ago in Norway. Norway continues to play the “model farm” role and Canadian aquaculture finfish companies are inundated predominately with Norwegian technology that was developed for the relatively benign Norwegian fjord environment. While these technologies work well in Norway they tend to be sub-optimal for use in the more robust Canadian environment.

In 2003, AEG was incorporated to develop technology and management solutions that were capable of safe, efficient and cost-effective operations in medium- and high-energy environments while remaining cost-competitive for low-energy environments. The AEG product portfolio is driven by innovation while our design philosophy requires that all AEG Solutions must meet five sustainability criteria to ensure products are socially acceptable, cost-effective, eco-friendly, professionally engineered and robust for survival particularly in higher energy environments.

AEG has been developing its component technologies since incorporation but integration of these technologies to work on a single site while raising fish had not occurred prior to this AIMAP project.

AEG Feeder
Virtually all existing feeding equipment, in feed boats or centralized feeders, use air blowers to distribute feed. Air blowing can result in significant feed breakage and the broken feed and/or dust is generally uneaten therefore affecting site FCR and adding considerable cost to the site operation (this cost can be as high as ~$350,000 per 1,000,000 fish raised through a grow-out cycle) and unnecessary environmental loading. Air blowers also create considerable noise pollution during feed delivery and result in a fish boiling behaviour that further adds to the total site noise impact. Noise pollution can result in unnecessary social conflicts with upland homeowners especially during weekends and holiday site operations.

The AEG Feeder uses an innovative water borne feeding technology that is less aggressive on feed pellets thereby minimizing feed breakage and subsequent costs and environmental loading. Further, hospital grade muffler systems are integrated to eliminate noise pollution and fish boiling behaviour during feeding and associated noise is completely eliminated. An animation is available on the AEGSolutions Youtube Channel illustrating generally how the AEG Feeder works.

In addition to water borne delivery, the AEG Feeder programming and PLC control offers enhanced versatility in site feed management. Seven feed pipes can be used within each onboard feed system. The deployed AEG 100MT Open Ocean Feeder has four onboard feed systems and therefore capable of feeding 28 feed pipes. The AEG Feeder versatility allows three general modes of operation:

• manual control whereby an operator might sit on the deployed feeder or within a nearby vessel and dispense feed while monitoring a feed camera mounted within each cage similar to the use of feed boats or other air delivery centralized feeders;
  
• a program which operates automatically using ‘meal feeding’ whereby each cage stock is offered the entire meal allotment, as determined by the site water temperature and a percentage of established feed table calculations based on fish biomass, before the next cage is meal fed in succession; or,
  
• a program that operates automatically based on a percentage of feed table allocation but with all cages on the site fed simultaneously through ‘pulse feeding’ whereby a portion of the total meal allotment is given to each cage in succession until the entire meal is fed. This level of automatic control is new to marine site operations but now allows fish in sea cages to receive hatchery-style feeding that they have become accustomed to prior to transfer to sea.

AEG completed pulse feeding control during Phase I of this project, which was then tested during this Phase II project. A recent video is also available on the AEGSolutions Youtube Channel showing fish feeding on the site using the AEG pulse feeding method of feed provision. Note that in the feeding video the fish are virtually fed at the surface but there is no aggressive behaviour during feeding; fish stress is completely eliminated during feeding, no noise pollution during feeding, and there is very little size discrepancy within the contained fish population. All of these positive outcomes are attributed to the hatchery- style of feeding provided to the sea cages with each meal being dispensed over an extended period of time (upwards of three hours in this case) and each pulse of feed provided within one minute of the previous pulse.

Another significant advantage of the centralized and fully automatic AEG Feeder with distance control is that fewer feeding events/days are lost due to foul weather. Our project site was entirely fed using the AEG Feeder; however, the site manager consistently noted feed days that would be lost if the site crew had to visit the site each day due to inclement weather

The total number of lost feeding days with crew feeding was 138 (69 days x 2 cages) based strictly on foul weather compared with 38 cage days with the AEG Feeder during the entire grow-out cycle. However, lost AEG Feeder days towards the end of June and throughout July, August and September were mostly related to adjusting the feed rates as the fish began to belch feed after reaching one kg in size and the water temperature warms up. These same days might have been lost also by crew feeding but not recorded as such as the weather on these days were fine to visit the site. Likewise, most AEG Feeder lost feed days in November and December was intentional to allow starvation for fish harvest. Again, similar days might also be lost using crew feeding if in fact the fish were at the target harvest size.

The AEG Feeder has a clear advantage in feeding fish during the more volatile late Fall, Winter and early Spring seasons. Note that the crew feeding lost feeding days are only representative of actual foul weather days experienced in St. Mary’s Bay. It is a general observation, however, that a site crew must focus their attention at least one day before a storm event on preparing for the pending storm and not feeding fish regardless of how calm the pre-storm day actually is. Further, at least one day would be lost while crew feeding after the storm to inspect the nets and moorings for damage and remove dead fish. Of course, our crew is also completing these necessary tasks to prepare for the storm and inspect following each storm but no feeding is lost during these days as the automatic AEG Feeder is performing the critical feeding task.

AEG will continue to develop feeding protocols with its advanced water borne delivery system while working with customers that have since purchased AEG Feeders and within our own commercial farming operations.

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AEG Containment Systems
Commonly used Atlantic salmon cages comprise of a net hanging within a collar that is permanently positioned at the surface and tied directly to the mooring grid. This approach requires a large footprint for the sprawling mooring system and results in frequent kinking damage to the surface collar and violent net movement during storms. Further, traditional cage arrangements are usually grossly underweighted in the site current resulting in exaggerated net bagging/folding and associated loss of volume and increased fish stress, damage and mortality.

The AEG Containment System was conceptually designed after years of operating an exposed high-energy Atlantic salmon site in the Bay of Fundy. The primary innovation in the AEG Containment System is that no mooring connections occur to the surface collar but all cage-to-cage and cage-to-mooring connections occur through the enhanced AEG Weight Ring. The enhanced weight ring maintains its overall geometric shape through inclusion of a series of spoke lines that extend from the weight beams to a central location in the middle of the bottom net, similar to spokes in a bicycle wheel. This strategy eliminates all point loads to the collar while providing a constant growing volume that greatly enhances fish welfare even in high current speeds and wave energy. AEG Containment Systems has been developed and field tested prior to this specific project but never to hold fish and raise the stock to a harvest size as completed in this AIMAP project.

The site experienced several significant storm events during the project period. The performance of the system in general is evident after reviewing the last image taken after the storm front had passed. The HDPE collar is bent out of shape as it conforms to the passing waves. The collar handrail is nearly fully submerged illustrating the importance to include a top net that is also constructed of smolt net mesh to ensure fish retention during storms while using the AEG Containment System. Another significant storm event was documented in early March 2010 while the project fish were present. Images from this storm were again captured by the AEG Feeder and 1 hr of 15 s images can be viewed at the AEGSolutions Youtube Channel. Many of these storms are significant enough that seaweed must be cleaned from the upper deck on the AEG Feeder.

As a side note, feed pipes are extending from the AEG Feeder to the AEG Containment System during the storm shown in the Youtube video to feed the contained stock. The blue buoys visible in the video provide the site operators with a visual indication that the feed pipes remain together during and after storm events. No scheduled feedings were missed during these storms, which would have otherwise disrupted feeding for at least 4-5 days per storm if crew feeding had been  used on this specific site as discussed.

The behaviour and performance of the AEG Containment System is also benefiting from the presence of a submersible HDPE collar that was developed as part of the Phase I AIMAP project. Offering HDPE collar submersion capability globally will provide farm operators an ability to effectively avoid many damaging surface perils including typhoons/hurricanes, algal/jellyfish blooms and seasonal ice flows to name a few. Furthermore, there is increasing discussion that submersion of Atlantic salmon to just 4 m depth can potentially reduce sea lice infestation.

Construction of our first proof-of-concept submersible HDPE collar was completed and field tested in December 2008. Timing for its completion was critical as the site frequently experiences heavy ice flows in February of each year. This situation was no different in 2010 as thick ice moved out St. Mary’s Bay while the project fish were onsite. The submersible collar was used to submerge the AEG Containment System on February 8, 2010 prior to the arrival of this ice flow and remained submerged for four days in this particular instance. The entire site was re-established at the surface when the ice danger was over and no damage was reported to the system or deleterious effect on the fish. This would not have the same outcome in the past when ice caused significant damage on at least two other occasions on this same site. Note that no feeding occurred while the cages were submerged as the AEG Feeder was disconnected from the cages and moved to shore rather than having a risk that moving ice might shift the AEG Feeder on its mooring and cause unnecessary damage to the submerged cages.

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Automatic Fish Stock Sizing
The AEG Feeder records the quantity of feed provided to individual cages each day and sends this information to operational managers via email in daily feed reports These reports are saved in a directory and reviewed prior to automatic entry into the AEG site information database – Neptune. Having daily fish size measures coupled with the already available feed data would provide immense opportunity for farm operators to better manage feed inputs, maximize FCR and growth, and plan/manipulate harvest schedules.

AEG has chosen the AquaSonar technology as the best possibility to integrate automatic fish size data. AquaSonar uses sonar technology to capture fish size data by placing a small transducer in the cage with the fish population. There is no time consuming data post-processing required and the technology is not limited by visibility or light conditions making its integration with the AEG Feeder quite appealing. This integration could provide immediate use of fish size data to adjust feed amounts and provide greater control of feed management. Further, actual fish sizes can be compared with predictive growth curves within Neptune to potentially provide superior harvest and market planning.

The AquaSonar is presently sold as a portable unit that is intended for short-term deployment within each cage so that an entire site can be measured over a 1-2 day period. Typically the operator would set the unit up at cage side, sample for a few hours in an individual cage by deploying the transducer, then retrieve the unit for redeployment in another cage. The AquaSonar unit calculates all fish sizes to reduce data post-processing.

The Phase I AIMAP project focused on permanently deploying a portable AquaSonar unit along with some hardware and software redesign to allow evaluation of direct integration with the AEG Feeder. The unit was outfitted with customized wireless communication capability through a WiFi connection to retrieve data from each unit. AEG personnel designed and built a water tight enclosure to house each AquaSonar unit so that it could be permanently mounted to the cage collar. A removable rechargeable battery pack powers the AquaSonar as the alternative use of a power cord extending from the AEG Feeder proved unfeasible on this high energy site. The battery was replaced as necessary with another charged unit to continue fish sizing. These approaches are certainly not sufficient for commercial sales but provided adequate opportunity for proof-of-concept technology integration.

The AquaSonar unit is programmed to sample fish sizes daily over several hours and is capable of storing several days of data. The existing computer onboard the AEG Feeder used the wireless connection to retrieve the fish size data from the AquaSonar. The AEG Feeder operator connected remotely to the feeder computer from a land based office and manually retrieved the data from the AquaSonar through the wireless link.

Several trends are clear from reviewing this snapshot of fish size data.

1.   Consistently collecting daily fish size data was not possible during the grow-out.
The ability to collect daily data was strongly influenced by surface sea-state conditions as major storms would render the mounted sonar system unusable with larger passing waves. Other conditions could also impede use of the sonar, including not changing the battery on schedule. Any of these conditions could result in having no data whatsoever for extended periods.

2.   Generally, the sonar system must record the size of at least 100 fish per hour over several hours to capture consistent data day-to-day.

3.   Collected AquaSonar data remained reasonably consistent with measured fish size using manual techniques when a sufficient number of fish were sampled by the AquaSonar. However, these sizes were also larger than initial growth projections indicating better use of feed and fish growth than expected.

4.   Several days of consistent data are required to allow trend analysis. Measured fish sizes should trend upwards over an extended period due to growth but certainly this might not be the case day-to-day. However, our activities provided sufficient proof-of-concept to continue with integration in the future.

Full integration of the AquaSonar system within the AEG Feeder was outside of the scope of this AIMAP project. However, these proof-of-concept results are very encouraging and sufficient to carry forward to the next stage to make full integration a reality. This will require completion of the following prior to commercial viability:

1.   A better means to permanently deploy the sonar system must be developed within the cage. Many issues were observed both with the collected data as well as watching the sonar on the site to suggest that the passing swell was causing difficulty for consistent and reliable data collection. This is caused by a tilting of the sonar while deployed and might be rectified by installing the sonar with a spar buoy design.

2.   At present, our efforts involved permanently mounting the hardware of individual portable units to individual cages. This approach is not practical or cost-effective as a full site solution in the future. A multi-plexer will need to be developed such that several deployed sonar units can communicate with a single centrally located piece of hardware.

3.   Energy use and battery requirement of the eventual multi-plexer will need to be addressed to allow practical use within the reality of a commercial fish farming operation.

4.   Automatic retrieval of the data from the AquaSonar unit, similar to automatic feed data retrieval, will require a redesign of the AquaSonar interface software and code changes for inclusion in the AEG Feeder communication system.

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Biological Performance
Technology performance must translate into gains within the biological performance of the fish to allow equipment sales in the future. Gains in population survival, feed management, growth, product grade and harvest date must all be realized to provide an adequate return on investment so that farm operators can clearly justify purchase of AEG Solutions.

Survival/Mortality
AEG accepted the trout for entry on the full salinity site based on them being a strain tolerant to saltwater. ~ 50,000 were delivered in mid-October 2009 but significant losses occurred within the first 48 hours following entry indicating an issue with saltwater tolerance. A decision was then made to hold the remaining stock in the hatchery for a few weeks to allow more growth to enter larger fish that might be more tolerant. An additional ~ 10,000 were entered in early-November with the same high mortality that resulted in a decision to hold the fish in the hatchery for a period sufficient to treat with Super Smolt. The final ~ 244,000 were entered in mid-December but with the same discouraging results. In total, more than 304,000 trout were entered to the full salinity site in St Mary’s Bay, NS but approximately 35% were lost over a several week period due to saltwater intolerance leaving just ~200,000 trout for grow-out.

The mortality rate continued to decline in the first quarter of 2010 until eventually settling to an acceptable commercial rate by April 2010. This declining mortality rate in January, February and March 2010 during the harshest weather conditions is in large part attributed to the use of internal nursery nets to initially contain the fish stock while on this very high energy site in St Mary’s Bay.

An acceptable commercial mortality rate is 0.6% of the population per month. We have no reason to believe that this mortality rate was also not achieved in the first quarter of 2010 but dramatically overshadowed by the saltwater tolerance issue. All of the other months in 2010 had a mortality rate below this target 0.6% per month with the exception of June and August 2010 with 0.91% and 0.89%, respectively. It is not known exactly why these months saw an increase in monthly mortality but these months did coincide with increasing water temperature and feed belching issues that could have created greater stress on the fish. Even with these two exceptions the quarterly average mortality for all but the first quarter of 2010 was below the 0.6% per month rate.

Feeding
The AEG Feeder allows feeding an entire site simultaneously with no requirement for day-to-day crew intervention or use of cameras. The AEG Feeder software allows automatic feeding based on established commercial feed tables that considers cage-by- cage biomass and measured water temperature. The biomass is adjusted based on incremental fish growth coupled with fish removal as mortalities, harvest or other site management decisions while the AEG Feeder measures the water temperature daily. Feed rates are further adjusted based on a percent of the calculated feed table provision to maintain an assumed FCR within an acceptable range.

Both cages were initially fed more than 100% of the feed table in the first quarter of 2010 as is typical while the fish are small. This rate was lowered to 100% as the temperature and growth increased in spring 2010. In early July, the trout began to belch feed creating an orange film of fish oil on the water surface as the water temperature warmed and the average size approached 1 kg. This can be a common occurrence when raising trout and widely accepted to be associated with use of specific feed ingredients that causes feed belching. Typically farmers continue to feed their stock at about the same rate when feed belching occurs in an attempt to offset the loss of feed and the site FCR suffers dramatically. We managed the site with daily communication with the site manager and gradually decreasing the feed rate to eliminate the feed belching. The decreased feed rate is clear in July and August and an increase in September as the threat of feed belching began to subside. The feed rate was maintained at 70-80% of the feed tables in the last quarter of 2010 as the trout reached the average target harvest size by mid- November and so feeding was adjusted accordingly to maintain the stock while easing off on growth.

The site FCR for the entire grow-out period was under 1.2. This compares with the typical trout FCR of 1.3-1.5 while raising the stock to an average target harvest live weight of up to 2.15 kg. This lower FCR is attributed to better overall feed management afforded by the AEG Feeder suite of programs, effectively managing the feed belching issue, elimination of feed breakage during the feeding process through the AEG Feeder water borne delivery system and maintaining a healthier stock of fish with nets that are consistently cleaned and therefore allowing well oxygenated water to flush through the cages.

Growth
The majority of the trout was entered in mid-December at an average weight of 91 g. The average target harvest live weight was 2150 g. Early projections had the stock reaching this average weight before the end of August 2010. However, this projected date was delayed to November 2010 due to the feed belching issue that was not anticipated
but experienced in July/August 2010 and required that the feed rate be dramatically reduced to about 65% of the feed table to keep the belching issue under control. Obviously reducing the feed rate had a profound effect on fish growth and time required to reach target harvest weights.

Fish fed using pulse feeding provided acceptable growth and feed performance results. Pulse feeding benefits should be more pronounced compared with meal feeding if more cages are to be fed as all cages would be fed simultaneously using pulse feeding compared with each cage in succession using meal feeding. These benefits might not be as evident in our case when feeding just a couple of cages as the meal fed fish are also being fed at the same time each day. We plan to restock the site to conduct additional feeding trials to develop optimal feeding strategies but hopefully with more cages to better understand the merits of pulse feeding within commercial settings. 

Fish Health
Fish health was constantly monitored during the grow-out cycle. On a couple of occasions the NS provincial vet visited the operations to monitor fish health and sea lice load. One of these visits coincided with an increase in mortality in June 2010. Fish samples taken at this time found that the trout were carrying a Vibrio species that is specific to trout and not covered by the salmon vaccination. This might be the reason for the increase in mortality but the issue was rather muted as the mortality rate declined to normal levels by July 2010. Sea lice were never a concern during the grow-out cycle.

Absolutely no pesticides or antibiotics were used during the grow-out. This further illustrates the capability of integrated AEG Solutions to provide superior fish welfare to maintain a healthy and stress-free stock even in the high energy conditions on the site.

Harvest
Harvest was initially projected to occur by late August at an average target weight of 2.15 kg (4.74 lbs) to produce an average dressed weight of 1.78 kg (3.92 lbs) at 83% yield. However, as the trout approached 1 kg in early July 2010 and the water temperature was increasing the population began to belch feed creating an orange film on the water surface. This issue is widely accepted to be associated with use of specific ingredients in the feed. Typically, farmers continue to feed their trout at the same feed rate but FCR increases dramatically with poor growth. We tackled this issue by programming the AEG Feeder to feed a much lower % of the feed table. This approach worked to eliminate feed belching and therefore minimize the associated environmental impact and maintain a low FCR. However, an unintended consequence of reducing the feed rate was slower growth and therefore not reaching the target harvest size until mid-November 2010.

Harvested fish were processed and marketed as either dressed with head-on (DHO) or fillets. In all cases, the fish were graded 100% premium. This in itself is quite encouraging given the ample opportunity for product downgrade through mechanical damage and with the present sea lice issue within the local salmon industry. Having no mechanical damage to the outside of the fish is a testament to the capability of the AEG Containment System to hold and raise fish on very high energy sites but without resulting net bagging and subsequent external damage to the fish stock. Avoidance of sea lice is likely related to the location of the site in isolation from other operators and the fact that trout were raised and not Atlantic salmon.

Harvested fish size was graded in two ways based on whether the final product would be DHO or fillets. In the case of DHO, the product was graded according to 2-4 lbs, 4-6 lbs and 6-8 lbs. A target trout fillet is 1-2 lbs. Therefore, the size grade categories for fillets were +/- 3.5 lbs based on a comfortable 65% fillet yield. This fillet yield is quite high for trout in the industry but was consistently acquired due to the attention of the plant manager and thick fillet resulting from trout raised during the project.

The remainder of the trout were graded based on +/- 3.5 lbs to produce fillets that are 1-2 lbs each. Upwards of 200,000 lbs of fillets were produced from the trout filleting. These fillets were all quite consistent in quality characteristics such as firmness, shape, size, gaping and color. All fillets were also given a premium grade with the color consistently given a rating of 27-29. This consistent flesh color is attributed to the AEG Feeder capability such that all fish can be fed each day as feed is supplied over an extended period of time.

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Logistics Mitigation
AEG continued to improve on logistics mitigation and document these strategies during this Phase II project so that buyers of AEG Solutions can benefit from our own operating experiences. This project objective is essential to AEG success as our present efforts represent the first time that AEG Solutions have been fully integrated on a single site to raise fish through harvest.

Nursery Nets
Integration of the innovative AEG nursery net system could represent a paradigm shift in the way that companies stock sites having higher than average energy conditions. This nursery net is possible due to the more robust structure offered by the AEG Containment System whereby individual 30-50 m nursery nets hang from more robust bird net stands and tie into the same enhanced AEG Containment System weight ring. Up to three individual properly sizes nursery nets can comfortably fit within a single AEG Containment System to allow effective triple stocking while not requiring physical stock splitting/grading when the fish are of size to be placed in individual grow-out systems.

Nursery nets offer marine site operators much greater control over fish and feed management compared with the standard operating procedures frequently used today in the wake of major disease outbreaks such as ISA. Smolt are stocked in hatcheries at a rate of 30-50 kg/m3. Present sea cage stocking strategies enter the required number of smolt into each cage such that the harvest stocking density is ~ 20 kg/m3. However, this requires that smolt are taken from their hatchery tanks at an average 40 kg/m3 and placed in large sea cages initially at < 0.5 kg/m3 and raised to the target harvest density of ~ 20 kg/m3. Use of smaller integrated nursery nets increases this initial sea cage stocking density to ~ 5 kg/m3. This is still not very high compared to the hatchery stocking density but certainly much better for the fish stock. Further, feed management in the early days following fish entry to sea cages should be much better as the fish stock are much more localized within a nursery net and therefore should be much better at sourcing provided food, especially while using an AEG Feeder with its centrally located feed diffuser in the middle of each nursery net.

Integration of nursery nets will be suggested standard operating procedures for all AEG Containment Systems sold in the future, especially to sites having high energy. In this case, current passing through the site will have to pass through 2 separate smolt nets and therefore effectively diminished to ~ 25% of the current that is experienced outside of the cage and nursery nets. This will greatly enhance fish welfare and survival rate on high energy sites while still allowing stocking of smolt that are the same size as those stocked on low energy sites. This strategy required minor redesign of the main net that must now include soft eyes inside and outside at the bottom of the net sides so that the main net can easily be tied to both the enhanced weight ring and internal nursery nets.

Net Cleaning
Perhaps the most significant operational change during the project compared with industry standards is the ability to cost-effectively clean nets while deployed. This essentially eliminates the need for expensive and risky net changes that are frequently performed in the industry. The site crew wash the sides of a 125 m x 10 m nylon net in about 3-4 hours using a single site vessel and dual head net cleaner. The bottom of the net is also washed in about four hours but requires dive support. This efficiency will allow a site crew to wash the sides of every net within a commercial operation every 10 days while the net bottoms need cleaning less frequently.

There has been some attempt in the industry to eliminate anti-foulants, including more frequent net changes and in some cases the introduction of novel but more expensive and lower volume cages that can rotate. Our net cleaning experience has been in the absence of these same net anti-foulants and so use of the AEG Containment System can now also allow companies to operate cages that are somewhat familiar to their site crews while still eliminate controversial anti-foulants.

Economic Analysis
Operational cash flow benefits associated with use of an AEG Feeder compared with crew feeding is abundantly clear following this project. Using an AEG Feeder will provide more than $867,000 in additional profit compared with using traditional crew feeding in feed boats in a single grow-out to raise 800,000 trout to a target harvest weight of 2.5 kg. The majority of this difference comes from a much higher feed cost using crew feeding due to the higher FCR, higher operational cost while performing net changes and using many more vessels to feed and maintain the site, and a higher labour cost to feed the fish using at least three feed boats. Clearly the return on investment from integrating an AEG Feeder within commercial operations is quite appealing. In fact, the purchase price for an AEG Feeder having sufficient capability and capacity to raise these 800,000 trout would be fully recovered within a single grow-out cycle.

This simplistic analysis does not consider further gains associated with a better market price from not using pesticides, antibiotics or antifoulants, perhaps a more consistent product quality for the market due to better overall feed provision and management, and much fewer lost feed days using an AEG Feeder compared with crew feeding. This latter aspect is very difficult to evaluate but certainly having lost feed days will delay harvest accordingly and therefore add costs from having to operate the site for more than the 13 months outlined. Further, the analysis does not fully evaluate gains coming from integration of other AEG Solutions used and developed during this AIMAP project. For instance, using AEG Containment Systems will have an additional capital expenditure for the commercial operations; however, the low mortality rate achieved during this project on a very high energy site would not be possible while using a conventional cage set-up therefore further reducing the profit attainable with fewer fish to harvest while using traditional cage systems.

Project Outreach
Commercialization is a central theme of AIMAP. This theme is commendable as participating companies would not be commercially viable if the resulting technologies are not commercially available. AEG is now very confident to sell advanced AEG Feeders and AEG Containment Systems based on our experience during this project. Further, the AEG site data management software was debugged and tested with real data collected through distance communication during this project and presently available coupled with the purchase of an AEG Feeder. Proof-of-concept activities involved development of a submersible collar that will be finalized for commercial sales and evaluation of the AquaSonar fish sizing technology, which provided encouraging results to continue with more complete integration and commercialization.

Several companies visited the site operations during the project to view working AEG Solutions. These companies represented an array of species and geographic regions including Canada, US, Australia and Europe. These visits coupled with sharing of information from ongoing project activities resulted in the sale of an AEG Feeder and multiple AEG Containment Systems. Discussions are ongoing for sales of additional items involved in the project with some anticipated to close during this fiscal year.

Conclusions
Phase II activities outlined in this report are a natural follow-on to technology-related activities completed in Phase I. The deployed AEG Solutions exceeded our expectations on a high energy site in terms of reliability, enhancing fish welfare, improving feed management and growing a very high quality seafood product in the absence of pesticides or antibiotics. Several companies visited the project activities resulting in the sale of an AEG Feeder and several AEG Containment Systems. Discussions are ongoing to close additional sales of AEG Solutions that are presently commercial-ready. Proof-of-concept project activities provided encouraging results that justifies additional effort to commercialize these products for eventual sale – including the integrated AquaSonar fish sizing technology and a submersible HDPE collar.