Thierry Chopin was born and educated in France. He obtained his Doctorate from the University of Western Brittany, Brest, France. He moved to Canada in 1989 and is presently Professor of Marine Biology at the University of New Brunswick in Saint John.

Dr Chopin's research focused initially on the ecophysiology, biochemistry and cultivation of seaweeds of commercial value. Around 1995, he became interested in developing what he called, in 2004, Integrated Multi-Trophic Aquaculture (IMTA).

He created the company Chopin Coastal Health Solutions Inc. in July 2016.



How did you come to be involved in this industry and, more specifically, integrated multi-trophic aquaculture (IMTA)?

My PhD, in France, was on the impact of phosphorus and nitrogen on the growth and production of the sugars called carrageenans in the red seaweed Chondrus crispus (Irish moss). Carrageenans are among the sugars extracted from seaweeds (phycocolloids) that we use every day without knowing it (from our orange juice in the morning to our toothpaste in the evening).

During my postdoctoral fellowship at Harbor Branch Oceanographic Institution, in Florida, I continued to look at the effect of phosphorus, more limiting than nitrogen in tropical environments, on carrageenan production in tropical/subtropical seaweeds.

I moved to Canada in 1989 and started working at the University of New Brunswick in Saint John. Until 1999, I pursued more work on phosphorus metabolism and the chemistry of phycocolloids.

By then, I had also realised that with the development of salmon aquaculture in the Bay of Fundy we had a significant source of dissolved nutrients available and that we could do something with them by recognising them as nutrients for another crop rather than wastes, or, using circular economy vocabulary, as co-products (what is waste for somebody is gold for somebody else).

In September 1995, I gave a presentation entitled 'Mixed, integrated, poly-, or multi-level aquaculture - whatever you call it, it is time to put seaweeds around your cages!'. I could see a number of faces in the room saying 'what is this guy with a strange accent talking about?'!

The period 1995-2000 was the period of 'preaching in the desert' for what was just 'integrated aquaculture'. We started to be taken seriously when we joined the network AquaNet in 2001.

In 2004, we gave a name to what we were doing: Integrated Multi-Trophic Aquaculture (IMTA).

The distinction between polyculture and IMTA is to recognise that in the first case, it could include, for example, three species of fish, while in the second case, the species are selected based on their complementary functions in the ecosystem, with a mixture of fed and extractive species, for example a combination of fish, seaweeds and invertebrates. Since 2004, more than 1,300 publications referring to IMTA have been published worldwide.

Over the years - with the support of several funding agencies and industry partners - we have been progressing along the continuum from R (Research) to D (Development) to C (Commercialisation) to make the Blue Revolution greener and mature into the newer ERA (Ecosystem Responsible Aquaculture) of the Turquoise Revolution!


Could you tell us about your work with seaweeds and what specifically your work involves?

Seaweeds serve as the IMTA extractive component for the dissolved inorganic nutrients in suspension. We select the species based on a combination of providing a significant biomass quite rapidly, being a good nutrient absorber/mitigator, being able to secure a market and fetching an interesting economic value. There has also been a lot of eco-physiological work required to find the right culture conditions, both in the laboratory and at sea, the right timing to transfer the little plantlets to sea, the depth at which to grow them, the appropriate cultivation infrastructure to deploy at the right place, and the right timing to get the seaweeds at their prime growth rate, maximal nutrient removal efficiency, and most interesting chemical composition. Designing efficient harvesting tools and early processing steps, depending on the type of products sought (fresh and dried), are still very important steps in the supply and value chains we are working on.

We also have to work on the other components of an IMTA system: the small organic particle suspension extractive component (shellfish), the large organic particle deposit extractive component (other invertebrates, such as sea urchins, sea cucumbers, worms, lobsters, and herbivorous fish), and , of course, the fed component (finfish). There is also another component of IMTA about which we know very little: the microbial mineralising component, which deserves much more investigation.


What are the most challenging aspects of working with seaweeds for the aquaculture industry? What common misconceptions are there about these organisms and IMTA?

If you are in Asia, there are very few challenges to working with seaweeds! They have been using them for centuries. The challenge is to persuade westerners that seaweed aquaculture is not only worth it, but it also provides many ecosystem services to which we should also allocate a value.

There are numerous common misconceptions and it has been quite a battle to dissipate them:

  • You are adding more biomass at/near fish sites, what will happen to oxygen levels? Well, seaweeds are photosynthetic organisms and are net producers of oxygen
  • Nutrients are not necessarily waste and recycling, encouraged on land and in agriculture, should also be encouraged at sea and in aquaculture
  • Will your IMTA products be safe to eat? Yes, we have eight years of data, accumulated with the Canadian Food Inspection Agency, and our IMTA products meet Canadian, USA and European regulations
  • It's too complicated for my crews. Yes, the people will need to be more versatile or some of your workforce will have to be trained for key periods when extractive species require extra work (for moving them to sea and harvesting, but the rest of the time you do not have to feed them). However, it can be done… look at what is happening in Asia.
  • Seaweed aquaculture is the low-hanging fruit of aquaculture. If growing seaweeds was so easy, there would be seaweed farms everywhere. Such is not the case, so, seaweeds must not be so easy to cultivate.
  • Western marine biologists and regulators tend to focus on animals because of the zoologically-biased education they have received since kindergarten! Unfortunately, that leads to very few being familiar with seaweeds and understanding their benefits. Implementing IMTA requires collaboration across a wide range of disciplines and industries; however, inter-disciplinary collaboration can be inhibited due to differences in language and methods. Funding for inter-disciplinary research can also be challenging to obtain
  • The scope of the IMTA concept is extremely broad and flexible and is always evolving. IMTA was never conceived with the idea of being viewed only as the cultivation of salmon, kelps, blue mussels and other invertebrates, in temperate waters, and only within the limits of existing finfish aquaculture sites. That is how we started in Canada, to be able to conduct experiments at sea, within the limitations of the regulations presently in place. In fact, IMTA can be applied worldwide to open-water and land-based systems, marine and freshwater (aquaponics) systems, and temperate and tropical systems. Consequently, it cannot be reduced to a short bureaucratic definition indicating species, type and number of infrastructures, distances, etc. There is no ultimate IMTA system to feed the world. It is its versatility that makes IMTA remarkable
  • It is important to put IMTA in its context of bio-inspired design, biomimicry, law of conservation of mass, circular economy and Integrated Coastal Area Management (ICAM), to understand its full long-term relevance.


The western world is waiting for proofs that IMTA makes economic sense. Can you convince them?

This is a fair question: will I make more money with these extra crops? A growing body of literature is emerging and demonstrating the economic value and benefits of IMTA. We have contributed eleven papers to the topic.

We have demonstrated that IMTA is more profitable than conventional fish (salmon) monoculture in the long term. It also reduces the economic risk associated with production variability and changing market conditions. Portfolio diversification is a well-known strategy on the stock exchange, as is crop diversification in agriculture; why would aquaculture be different? Basically, do not put all your salmon eggs in the same basket!

Extensive household surveying and focus group studies demonstrated that consumers consider IMTA products safe, and are willing to pay more for them, averaging 9-10 percent more for IMTA-labelled products. We were able to reach a price premium of 11 percent for IMTA salmon called 'WiseSource Salmon' by the leading food retailer in Canada, Loblaws.

Production from IMTA systems, especially if combined with eco-certification labelling, could prove useful in increasing the desirability of Atlantic salmon and the likelihood that consumers choose the product. A contingent behaviour method analysis indicated that Canadian salmon consumers would derive benefits of at least CAD 280 million per year for the first five years after the introduction of IMTA salmon to the market. A contingent valuation method analysis indicated that non-consumers of farmed salmon would derive environmental benefits from the adoption of IMTA of between CAD 43 and CAD 65 million per year over the same period.

Finfish aquaculture is currently being increasingly scrutinised, as the public grows more sensitive to food production methods and environmental sustainability issues. IMTA improves public perception, thereby helping the whole aquaculture sector gain additional societal acceptability.

Consumers have a more positive perception towards IMTA than closed containment aquaculture (CCA): 44.3 percent of the respondents preferred IMTA to conventional net-pen technology, whereas only 16.3 percent of the respondents preferred CCA. While the respondents perceived both methods as environmentally friendly, 70 percent of the respondents who chose IMTA felt that it was more 'natural' than CCA.

The majority of salmon consumers are aware of the environmental concerns surrounding conventional salmon farming and 63.5 percent of them are supportive of adopting a more sustainable salmon farming method even if it is more expensive. The majority is willing to pay a premium for reduced environmental impacts from the aquaculture industry.

In British Columbia, the consumer perception of IMTA is mostly positive and oyster production could increase significantly with the adoption of IMTA, with important shellfish market implications resulting.

Interestingly, these papers used data provided by the aquaculture industry. Despite all these studies demonstrating the positive financial results of IMTA systems, their adoption at commercial scale in Canada, and other western countries, appears slow. We have to recognize that these studies only span the last decade. It always takes time for the knowledge acquired in academic studies to be transferred to the industry, investors and regulators. Science and society need time to think, digest and then appropriate new ideas as their own, and evolve.

When IMTA is implemented at a larger scale, invertebrate and seaweed productions will certainly increase and so will their contribution to the total revenue of a company, making IMTA more attractive to investors.

Politicians, of all sides, have regularly promised a doubling of the aquaculture industry for 2000, 2010, 2030 or 2050! In places like New Brunswick, on the east coast of Canada, where salmon production has, in fact, declined, where will that doubling come from? Clearly, it will come from crop diversification, with seaweeds and invertebrates, which could provide economic stability and resilience, and encourage industry development, rendering IMTA a more attractive practice in the future.

Moreover, scientific literature on the economics of IMTA has focused predominantly on the financial side, which is a critical piece of the puzzle but one that ignores the full range of societal benefits associated with IMTA. Given the potential environmental benefits of IMTA, additional economic analyses, that take into account positive and negative externalities associated with production, are needed to demonstrate the true value of IMTA to society.


What has been your proudest achievement whilst working in this sector?

As the Scientific Director of the Natural Sciences and Engineering Research Council (NSERC) Strategic Canadian IMTA Network (CIMTAN) from 2010 to 2017, I am particularly proud that training highly qualified personnel (HQP) became one of the key missions of the network. In fact, the number of HQP was exceeded: instead of our goal of 114, we managed to train 137 (120%): 76 undergraduate students, 35 Master students, six PhD students, seven postdoctoral fellows, 12 technicians and one research scientist.

It is important to develop a versatile and interdisciplinary workforce if we want the scientists, policy influencers, decision makers, regulators, and industrialists of tomorrow to be innovative and build a more diversified and responsible aquaculture sector.


How important do you think an academic background is for those wanting to have a career in aquaculture? Would you recommend technical expertise or academia to young people interested in the industry?

What is key is interdisciplinarity, as, often, the solutions are at the interfaces of various disciplines. Moreover, if in agronomy, you need a green thumb, in aquanomy, you need a green thumb and a blue thumb!

CIMTAN enabled the priming of young talents so they could enter a highly skilled labour force well-prepared, capable of thinking critically and independently, exposed to the interdisciplinary approach to problem solving, having already acquired a useful combination of technical skills in several academic and industrial fields and, consequently, well-positioned for jobs in several sectors, being academic, industrial, regulatory or non-governmental.

It is interesting to see how these HQP have become respected professionals in several sectors and, in fact, IMTA ambassadors in several provincial and federal agencies and companies, where they will gradually change some attitudes, especially in regulating agencies. They have been remarkable agents of knowledge dissemination and technology transfer.


How can seaweeds and IMTA help transform aquaculture into an increasingly more sustainable industry and efficient food production systems of the future?

Seaweeds can grow without fertilisers/agrochemicals and do not need to be irrigated, on a planet where water availability is, increasingly, becoming an issue.

Seaweed cultivation does not need more arable soil or land transformation (no deforestation).

Seaweeds provide other ecosystem services, such as nutrient biomitigation and habitat restoration, contributing positively to the United Nations' Sustainable Development Goals (SDG), especially SDG 14 (Life Below Water).

Seaweeds are the aquaculture component sequestering CO2 and providing O2, while the other animal and microbial components consume O2 and release CO2.

Seaweeds can help reduce climate change and coastal acidification impacts. By sequestering carbon dioxide dissolved in seawater, seaweeds can play a significant role in increasing pH in coastal seawater.

Dietary shifts towards the consumption of sustainable, safe, equitable, resilient and low-carbon sources of food from the ocean (such as seaweeds, invertebrates and fish) will reduce gas emissions and carbon footprints from animal land-based food production systems, and contribute significantly to climate change mitigation to keep global temperature rises below 1.5˚C, by 2050, to reach the targets of the Paris Agreement.

Seaweeds welcome vegetarians and vegans into the seafood world by offering access to highly nutritious ocean-based, plant-equivalent food sources from pristine waters.

By eating more seaweeds, people will participate in the decarbonisation of this world and contribute, at their level, in making the Blue Economy greener. That is what we call the Turquoise Revolution, fostering sustainable economic growth in coastal communities and regions.

We need a major rethinking regarding the functioning of an 'aquaculture farm'. It does not work only within the limits of a few buoys on the water, but should be managed using an ICAM strategy, according to the movement of the different elements considered. If organic particles released by the fed component settle quite rapidly, dissolved inorganic nutrients travel longer distances. This means that different strategies (in space and time) will be needed to recover these different nutrients, and that entire bays/coastal areas/regions should be the units of IMTA management. It is, indeed, opening the Pandora's box of regulations. The apathy for changes can be frustrating. However, harmonisation and coordination between regulatory departments and agencies is necessary.

We need to change our attitudes and business models to evolve from the linear approach (one species – one process – one product), used far too often with fishery and aquaculture products, towards the Integrated Sequential Biorefinery (ISBR) approach (one species – several processes – several products). This fits very well with the circular economy approach, in which by-products are no longer considered wastes but co-products, which can be valued in other applications.


What would you say are the major challenges for the aquaculture industry, that we will face in the next five years? How can we try to combat these issues?

To bestow IMTA its full value, extractive species need to be valued for not only their biomass/food trading values, but also for the ecosystem services and the increase in consumer trust and societal/political license to operate that they provide. The value of the ecosystem services should be recognised, accounted for and used as financial and regulatory incentive tools (for example, the development of nutrient trading credits). In the coastal environment, it is not only a carbon story; consequently, we have to enlarge the debate from carbon tax to nitrogen and phosphorus taxes. However, I prefer to identify credits, instead of taxes, for those implementing sustainable practices.

The IMTA multi-crop diversification approach could be an economic risk mitigation and management option to address pending climate change and coastal acidification impacts.

IMTA could also be a model of benign aquaculture practices compatible with activities in Marine Protected Areas, where local human populations could find sustainable employment, instead of being uprooted to allow the development of reserves for well-off tourists. IMTA could provide local food and nutrition security, alleviate poverty, and contribute to the socio-economic resilience of local communities. Aquaculture ecotourism could go a long way toward helping the aquaculture industry gain societal trust.

IMTA systems could also be associated with wind farms in integrated food and renewable energy parks (IFREP) to reduce the cumulative footprint of these two activities.

Aquaculture is more than a fish story! There are also invertebrates, seaweeds, micro-algae and other micro-organisms in the oceans! We need an ecosystem approach to solve the issues. Seaweeds are part of what is now called transformative opportunity areas (TOPS) because they are at the intersection of many topical trends. They provide many multi/inter-sectorial benefits: a) they are a source of food and many other applications (some reaching very high return on the investment); b) they provide several key ecosystem services; c) they allow local diversification of a more balanced aquaculture industry; and d) they participate in the dietary shift towards more decarbonized ocean-based sources of proteins.

We know that the demand for nutritious and diverse food is accelerating with an increasing human population. Aquaculture already contributes a significant share of the production for our daily intake not only of proteins, but also carbohydrates and lipids. However, if it wants to continue to grow, the aquaculture sector will need to develop more innovative, responsible, sustainable and profitable technologies and practices.

The implementation of IMTA is challenging the present management of aquaculture companies and the different levels of policies and regulations. In many countries, the governance and regulatory framework in place for aquaculture is designed with a single species/group of species in mind, just like fishery regulations, and can inhibit a more holistic approach by not considering species interactions and an ecosystem-based management approach. For example, in New Brunswick, the regulations put in place more than two-to-three decades ago, at a time when everything was viewed through the lens/model of salmon aquaculture development, are now inadvertently resulting in regulatory and economic hurdles preventing the development and implementation of innovation in aquaculture practices. If we want to implement IMTA at the appropriate scale, we will need enabling and flexible regulations (using, in particular, an ICAM strategy) and conducive societal conditions.

As we are in the middle of this COVID-19 pandemic crisis, what are the lessons we can already see emerging? 1) Produce more locally; 2) Shorten food supply chains. Both can be addressed by IMTA, which can deliver locally a greater variety of seafood products, as it combines the production of fed species (finfish) and extractive species (seaweeds and invertebrates). Moreover, with fed species providing co-products usable by the extractive species, more balanced aquaculture systems are being developed to counter the increasingly unbalanced regions of monocultures (being monocultures of fish, invertebrates or seaweeds). Seaweeds represent 51.2 percent of marine and coastal aquaculture organisms. We could rejoice at such a high percentage of extractive species, but we should also understand that 99.4 percent of seaweed aquaculture is concentrated in seven Asian countries. So, we have not yet balanced the different production types of aquaculture at a worldwide scale.

Paradoxically, it seems that some NGOs are now very favorable to the development of aquaculture, as long as it is of extractive species. I would, however, argue that too much of a good thing can also be detrimental. For example, there is presently an infatuation for sea-cucumber aquaculture, but in a region with too many farms of extractive species, the time will come when there will be nothing left to extract. The 'soup' (the seawater and the sediments) needs to be rich (in nutrients, organic and inorganic) to be nutritious. Hence, the idea of combining fed and extractive species. The art is to find the equilibrium provided by moderation and diversification (environmental and economic).

We have to recognise that we are still in the infancy of western IMTA. IMTA adoption will not happen overnight, especially in the western world, which presently prefers monocultures, linear processes and short-term profits. We will need patience, determination and persistence to get people to see the advantages of growing complementary species together, creating circular economy processes and seeking long-term sustainability.

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