Is Tuna Farming On The Brink Of A Revolution?

The farming of bluefin tuna is a segment of the industry which is seeing more and more investment and development, a hint that we might be getting closer to being able to fully farm tuna on a large scale, and seeing this product sold on the market in significant volumes. However, there are still many challenges left for full-cycle aquaculture of tuna to become a viable investment opportunity. A number of projects have failed in recent times, but optimism from several groups on the possibility of getting this fish to the market remains.

Tuna is still lagging behind similar successes made for other fish species such as salmon and carp, which have long been cultivated from egg to adulthood. Succeeding with tuna seems to be a much bigger challenge than with other fish. There are several examples of companies that have thrived in full aquaculture of tuna, but it is still on such a small scale that a very low number of tuna fully bred in captivity reach the market.

One essential aspect of tuna farming is getting the fat content right, as the fattiness of the tuna is what makes it stand out from other fish, and gives it higher value. High prices, especially in Japan, are paid for this species, and that is what motivates companies to venture into the challenging world of bluefin aquaculture.

While fattening of bluefin has been a successful venture for many companies, the story is different for those trying to bring tuna that has been raised from egg to adulthood to the market. Not only is the production filled with challenges, it is also a costly process.

A pioneer in tuna farming is Kindai University in Japan. Professor Sawada Yoshifumi from the institution tells Atuna that some of the top challenges of full-cycle tuna breeding is developing the right hatchery technology, improving the tuna’s growth rate and finding a solution to issues such as disease and stress, as well as feed conversion. He explains that the reason why some hatchery projects fail is that they lack sufficient research, in addition to investors not having enough knowledge and experience in the field of aquaculture.

Yoshifumi argues that there is demand from consumers for fully-farmed tuna, especially in Japan, as they are concerned with the sustainability issues regarding fish that is wild-caught. In Japan, several big fishing and trading companies are already investing in full cycle aquaculture, with these ventures having grown notably in the country in recent years, at a much faster pace than what has been seen in Europe, where Spain is the main pioneer. Bluefin is an important part of the Japanese diet, so the urgency to be able to sustainably provide this fish to the market has been in the focus, and has perhaps been driving the Japanese firms to prosper at a greater rate than the European ones.

One bluefin project that was recently halted was an attempt by Spanish exporter Ricardo Fuentes e Hijos subsidiary Fortuna Mare to hatch bluefin larvae in Spain. The venture failed, leading to millions of dollars in losses. Reasons for the letdown are said to have been troubles in transporting the larvae, causing many of them to die. Currently, the survival rate in the hatchery stage of farming is around 10 percent, with the survival rate of larvae having been deemed one of the main challenges in the farming process.

As well as difficulties in making sure the fish survives in its early stages of life, another major issue is the massive amounts of live feed in form of small wild fish such as sardines needed to feed bluefin. This makes up one of the main counter arguments to those who state that bluefin aquaculture is more sustainable than wild fishing. The Feed Conversion Ratio (FCR) currently stands at around 28:1, which means that 28 pounds of food is needed to raise one pound of tuna.

Tore Remman from C Feed, a Norwegian company which produces alternative live feed, in the form of farmed copepods (a small crustacean) for marine species, with tuna being one of them, tells Atuna that the firm has seen good results from using their product for tuna larvae, which he states is one of the most critical phases when it comes to tuna farming. “One of the biggest challenges when it comes to tuna farming is the survival and quality when hatching larvae from eggs. This has been proved impossible with the live feed of today, but the solution with our copepods has given very good results,” he says. “There’s few, if any, who are able to hatch and farm tuna from eggs,” he adds.

C Feed is not the only firm which is making innovations when it comes to tuna feed, and some are also developing vegetarian options. Mark Albertson, Director of Strategic Market Development for Illinois Soybean Association (ISA) states that a new soy bean based feed his company has created in cooperation with US aquaculture firm Ichthus Unlimited can be the solution to the feed conversion obstacle in tuna farming.

He states that their new tuna soy bean fishmeal will help make tuna farming more sustainable, and claims the new

soy fodder can reduce the FCR, and therefore the amount of food needed, to 4:1. Albertson also claims that it is much better for the environment than fish, as it floats and therefore can be more easily monitored and retrieved if uneaten.

The economics of the feed is an important key to sustainability, Albertson explains. Going forward, the firm will be using tuna fingerlings from a hatchery to try and prove that the feed can produce healthy and nutritious harvest-size tuna more economically than the current practice of using wild caught sardines, to grow wild tuna to harvest size. “We are on the brink of a revolution in the tuna industry,” states Albertson.

And although most tuna farming is limited to only bluefin, ISA has also experimented with feeding yellowfin, stating that despite the different sizes in the fish, it has not been able to conclude that there are significant variances in the dietary requirements of these species.

His colleague from Ichthus, Alejandro Buentello, adds that this new feed also reduces the environmental impact of tuna farming, as well as being cost-effective. “Therefore, it resolves one of the bottleneck issues of the tuna industry: the unsustainable feeding with baitfish,” he says.

He adds that tuna aquaculture is a high-risk and high-profit form of aquaculture. “Through research we are trying to reduce risks and provide sustainability and permanence to this industry,” he says, emphasizing that investment in both tuna aquaculture, and sustainable wild fishing of the species are viable for the future. 

However, there is a possible drawback to using other feed than wild fish. Tuna’s consumption of smaller fish is a way for it to take in omega 3 nutrients, especially the components DHA and EPA. When soy feed is used, however, this benefit could be lost and consequently the tuna would contain less omega 3 when it reaches the market. This would mean that tuna could lose one of its strongest selling points, its elevated levels of omega 3, which is very beneficial to human health. Additionally, there are also concerns about the sustainability of farming soy crops, as this practice has been associated with deforestation, as well as soil corrosion and pollution of ground water with pesticides. 

There are still a lot of unanswered questions in relation to what are the most efficient and bulletproof ways of raising bluefin. Although some have innovated new feed that can significantly reduce the amount of forage needed in farming this species, said to make it both more economically and environmentally friendly, others state that this can have a negative effect on our health. This, and a number of other issues still need to be solved before fully farm-raised bluefin tuna -from egg to adulthood- becomes a product commonly sold in supermarkets all over the world.

Even though many new bluefin ventures fail with significant financial losses as a consequence, belief appears to still be strong over the fact that complete bluefin aquaculture is a viable investment opportunity for the future.

Bluefin is the tuna species that is met with the highest level of concern when it comes to sustainability. Although some populations of the fish are said to be recovering, the Pacific stock is reported to only be at three percent of its pre-fished level. It is clear that something needs to be done to ensure continued supply of the Japanese’s favorite fish. However, only time will tell if this will be done through full cycle aquaculture, fattening, or sustainable fishing, or a combination of all three, and still bring the highly valued fatty delicacy to awaiting consumers.