As the aquaculture industry continues to evolve, methods of production will continue to change, as will people's attitudes about the way we approach both environmental and commercial aspects of the industry. I have observed through my travels a marked increase in the discussion of polyculture (the growing of one or more species in conjunction with a primary species) with very positive outlooks, as well as genuine concern for the unknown, as well as unfounded concern based on self-agenda theory ideals.

In almost every case we were able to develop solutions for the concerns through husbandry engineering; what was interesting however was how little is known about the term polyculture by the people who could really take advantage of it.

Polyculture could be looked at as the primary and secondary production of marine finfish and aquatic plants, marine finfish and shellfish, shellfish and shellfish, or a combination of all three. Depending on your focus there are a number of application possibilities that you should consider.

For this discussion I will primarily focus on applications with shellfish because of our strong references in this area, and because of the ease of co-marketing the production to the consumer. Marine finfish as well as shrimp farms have a lot to gain by involving polyculture applications in their existing operations, and most already have between 50% and 80% of the necessary infrastructure in place. Watercraft, lease area, processing buildings, cold storage, transportation and distribution networks are already there. The investment for the balance of the deployed gear, as well as the processing and handling equipment, is miniscule compared to the value of the crop. What is missing is the understanding of the shellfish industry and growing technology.

The fact of the matter is that shellfish have been overshadowed all over the world by other species for quite some time. There are exceptions of course, like Spain, New Zealand, France, etc., but they are not the rule in the aquaculture industry.

There are many reasons for this and they are quite varied, however most people's reference on shellfish is that of ranching (bottom culture) instead of intensive (mid water) farming, where you control the animals (like finfish and shrimp). It is easy to see why the shellfish sector is being viewed like this with business people seeing it as "risky business", and in general not treating it very seriously.

This is not unusual in most parts of the world, and in fact is rather the norm. However, as those who are at the forefront of the shellfish industry know, change is happening. New technology in shellfish husbandry is well underway and is making a major difference to the bottom line.

The overall response from those with the greatest interest in polyculture applications, is surprise in how far husbandry methods have advanced, as well as the market and profitability that are available in both the domestic and export markets.

It is important to note here that shellfish culture worldwide is going through a paradigm shift, from "How cheaply can we harvest product and sell it to a commodity market?", to "How quickly can we grow and produce a quality product in volume, and market it to consumers who enjoy the product as well as those who haven't yet consumed it?"

Factors such as shell shape, flavour, value added before harvest, and shell colour for branding purposes, are already in play.

Advances in husbandry methods allow for control of a lot of these, as well as of labour and bio-fouling. The market continues to grow because people have discovered that the healthy food value, combined with the exotic nature of shellfish, fits their lifestyle, and besides that, they just taste so good!

We recently opened a consulting division, which allows us to use all our travelling and observations of farms over the years to assist in the growth of the industry. One of the services we offer is farm or lease audits and potential studies.

It was while working on an audit of an existing oyster farm - which was operating at what the owner thought was an efficient production yet was well below what it could have been - that I realized how latest technologies weren't being implemented. If common business practices for combined maximum output yield and profitability had been implemented the farm would have been much more profitable.

As this is more the norm in the shellfish sector then it really should be, it becomes more logical to understand why finfish operators have not been as interested as they could have been in polyculture.

Without doubt one of the more important benefits of shellfish polyculture is in the way it addresses the high nutrient loading areas around marine finfish sites and shrimp pond outputs along select coastal regions. Turning an environmental issue into a cash flow profit center does not present itself very often.

I was on a mussel raft some time ago, in a bay on the Pacific Coast of North America, where you could actually see how well this works. The current flow of nutrient loaded water was actually exiting the raft on the other side noticeably clearer then the water on the side flow or at the entrance side of the raft.

Using the latest in grow out technologies, high quality, top grade oysters could be grown in record time with low labour cost, adjacent to shrimp farms. While there are a number of systems that are applicable the choice would depend on the site parameters and the objectives of those involved. You can get a better idea of the systems available and how they work at our web site www.fukuina.com.

The business end of things, no matter which system is being used, is impressive, with a gross income per hectare from oysters in polyculture with shrimp averaging US$195,000.00 with an amortized deployed capital equipment cost of US$7,500.00. With Mother Nature doing most of the labour with the new technology equipment available, this leaves some very handsome profit margins for shrimp farmers to look into.

Finfish growers, depending on where they are located, can work with mussels, oysters or scallops with similar high value results. The key to moving forward is to understand that anybody can grow shellfish, but to do it profitably you need to understand and implement the entire process of doing so, from the larval stage to the dinner plate.

Countries like New Zealand have already been producing mussels in polyculture applications adjacent to their salmon farms. They have been using traditional longlines to date, however in some areas intensive raft culture will have its advantages in allowing movement of the shellfish during times of medicated salmon feed applications. Unfortunately, in general most finfish growers are not familiar with shellfish, and in most cases see them as a nuisance instead of profit centers, and as an appeasement of the case of the environmentalist movement.

Within most government circles, polyculture is an unknown, or ignored in its value. For example, in British Columbia, Canada there exists a regulation that states that shellfish farms must be a minimum of 125 meters from salmon farms, which diminishes the effectiveness of the nutrient loading uptake which is the goal.

There still needs to be some base line research done dependant on the geographic sector, however the team of specialist that we have assembled in our consulting division will probably be kept very busy providing answers and solutions for companies and governments as this area of aquaculture continues to unfold.

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Contact Don Bishop at:
Fukui North America

110-B Bonnechere St.W.
Eganville, Ontario K0J 1T0
CANADA

**NEW**Fax: 613-432-9494
Email: don@bishopaquatic.com or don@bishopaquatic.com

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