Sustainable Barramundi Fish Farming, by Clay Ferguson

It took thousands of years for the world human population to reach 1 billion people, and in the past 200 years it grew sevenfold (UNFPA 2016). In an inevitable reaction to this growing revolution, man has revolutionized simple fishing and netting techniques into complex controlled systems of domestication, called aquaculture. Aquaculture quickly became popular throughout the world with many species for the main reason that there was no laborious and time consuming ‘fishing’ involved. However, in today’s society, aquaculture has taken on a different role in which its main purpose is to help sustain and subsidize for the huge biomass we exploit every day. Although aquaculture practices have changed dramatically through their existence, the species domesticated have not varied much. Since the common carp’s first application to aquaculture, species including mussels, shrimp, catfish, tilapia, salmon, trout, bass, and other fin fishes have made their names in the list of cultivable species (Rabanal 1988). All species have a relative aquaculture weaknesses be it temperature or pH tolerance, feed to growth ratio, or even stress. Tilapia have been a top species choice for many aquaculturalists due to their hardiness, growth rate, and stress tolerance, but the Barramundi (Lates calcarifer) has begun to shine where even the tilapia has not.  Barramundi seem to have a positive reaction in every checklist aquaculturalists have for potential species. They are hardy like the tilapia, taste like a cross between a snapper/grouper and halibut, contain optimum omega-3 levels with minimal negative omeg-6 levels, are omnivorous, can be raised without hormones, and most of all has one of the quickest food to growth ratios of any domestic species (Briter 2014). The barramundi has taken off across the world as a premier species suited for aquaculture because of these reasons and as scientists and farmers look to enhance the successful applications of this fish, developmental questions arise as to what farming strategies or even what environmental conditions when applied to barramundi culture will produce the best quality sustainable fish.

           

Barramundi (Lates calcarifer)  Source: Queensland Government

            Barramundi can be found in Southeast Asia down to Australia. They are oviparous fish that will lay millions of small pink eggs, which hatch within 15 to 20 hours (Thorne 2011). All barramundi start their lives male and in fresh water river systems, living there for a few breeding seasons before venturing to brackish or saltwater. Females do not appear until around the age of 3 or 4 creating a rather unique social and reproductive system. They grow rapidly averaging around the 1.5:1 kilogram of food to kilogram of weight growth in captivity (Thorne 2011). Captive barramundi have been found to have higher omega-3 and better omega 3-6 ratios than their wild counter part (Nichols et al 2014). These two attributes both create high demand from consumers choosing the healthy fish and benefit farmers because they see faster money return compared to other species. Barramundi demand a high protein diet for optimum growth, although scientists are attempting to reduce the reliance on wild caught fish as food. Achieving a truly sustainable farm requires research that can maintain high growth rates and taste, but not exacerbate already diminished primary consumers of our oceans.

           

Barramundi in grow-out tank.  Source:  Australis

            Industrial farming of the barramundi originated in Australia and South Asia in the mid to late 1900’s. For centuries they have been considered a prized sport fish exceeding 90 pounds and offering an intense battle when hooked (International Game Fish Association 2016). They have also been fished commercially, but are now governed by seasonal closures along with tackle and gear restrictions. Unlike many species, barramundi were not hatched and grown in captivity for population replenishment plans, but rather as a direct food source without the trivial and tidal patterns fishing can impose. Australians recognized their premium eating qualities and have industrialized into over 100 licensed farms throughout the country (ABFA 2008). These farms range from fresh to salt water ponds and cages to indoor recirculation systems. Outdoor grow out facilities, however, are strongly subjected to the environment they are established in, limiting feasible aquaculture locations and growth enhancing techniques. In order to command a better control on the entire life process and yield of the barramundi, Recirculating Aquaculture Systems (RAS) are the desired system across the world.

One major company in America growing barramundi in a commercial RAS system is Australis, Turners Falls, MA. Picking the barramundi was easy for Australis because, “The Sustainable Seabass has the same sweet, flavor and meaty texture as other Seabass, yet its unique eco-friendly profile makes it unlike any other fish available (Guerriero 2011).” Yet to run a successful barramundi operation, a RAS systems was absolutely necessary to maintain the optimum 25 degrees Centigrade for the species. Benefits in a RAS system can seemingly venture as far as technology can be advanced. Australis among many commercial aquaculture businesses utilize computerized sampling systems like Argus Control Systems or OSMOBOT to constantly regulate and record water variables such as: pH, dissolved oxygen, temperature, ammonia, nitrates, and many other important minerals (Stein and Holowko 2016). Any dramatic fluctuations in these variables can induce stress in the fish and increase chances of disease or death; therefore automated systems are crucial to maintaining optimum environmental conditions for the barramundi. Furthermore, automated systems can greatly reduce the workforce both in labor and time allowing for more focus on marketability and other business interests. Australis has eliminated many negatives impeding the growth of aquaculture systems by ensuring a closed loop system. This means they can ensure the barramundi, a non-native species does not happen to escape into our native waters and pose invasive issues. Also by using a circulatory system, Australis is not continually taking in, contaminating, and depositing water back into our streams. RAS systems are designed to use the same water for an extended period of time by way of filtration stages both physical and microbial/biological. Australis’ tank design has setup a continual hierarchy of similar sized fish giving them “more space to swim as they grow” and enabling each fish the equal opportunity to feed and become marketable (Guerriero 2011). Australis has developed a thriving international business through technological advancements but no factor is any more important than the principles of the barramundi’s ecology and lifecycle.

Barramundi is Australia's favorite fish, also known as as Asian Sea Bass and The Sustainable Seabass™ Source

There are many aspects that have yet to be analyzed to increase the sustainable level of farming this fish. Experiments are continuing to be funded for barramundi aquaculture research regarding challenges of manufacturing the best feed or even what water salinity yields the best tasting, growing, and healthiest fish. Australian Farmer Kel Gordon has designed an aquaculture system that grows quality barramundi but also rids of time and money a farmer has to invest in his system. His Pod system needs no pumps, is vertically integrated, overcomes cannibalism, limits stress to a minimum, and has been proven to return 37% profit within second year (Gordon 1999). Engineering ingenuity that saves farmers money while at the same time builds off of the ecological strengths of the barramundi is rapidly labeling fish farming as an efficient and sustainable practice. This is crucial since farming fish relies completely on what consumers think of every aspect of the system.  Looking beyond aquaculture RAS techniques, barramundi are now being trialed with past successful aquaponic plant species in fresh water systems. This conflicts with farmers who prefer salt water to produce best barramundi flavors, since they will not have the option of the highly desired freshwater plant species like tomatoes, lettuce, and strawberries (Diver 2006). This has opened a window for marine vegetation such as kelp and seaweed that has recently grown into a high demand international market. Establishing an aquaponics system can be expensive therefore setting up an aquaponics system that utilizes barramundi waste to produce additional profit is wise. Government subsidies are often provided if certain standards are met and if alternative energy like solar or geothermal are used in the RAS (Barclay 2015). In order to keep up with the increasing human population, it is of utmost importance that farming becomes sustainable, utilizing every phase of the system while reducing the amount of land needed. Although there is much research and technological advancements to come, the barramundi seems to be the future of sustainable aquaponic farming.

References

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Barclay, E. 2015. Investment Fund Pours Cash Into Cleaner, Greener Fish Farming. WVTF Public Radio NPR, the salt. Available: http://www.npr.org/sections/thesalt/2015/01/22/379090302/investment-fund-pours-cash-into-cleaner-greener-fish-farming/. (accessed April 2016)

Briter, P. 2014. Mariculture in the Northern Territory Barramundi. Sustainable Seas and Sustainable Aquaculture. MESA. Available: http://www.mesa.edu.au/aquaculture/aquaculture08.asp/. (accessed April 2016)

Diver, S. 2006. Aquaponics- Integration of hydroponics with Aquaculture. ATTRA- National Sustainable Agriculture Information Service. Available: http://cichlidfish.net/Ebooks/aquaponic.pdf/. (accessed April 2016)

Gordon, K. 1999. The Pod Recirculating Aquaculture System. Aquafarmer Australia Pty Ltd. Available: http://www.aquafarmer.com.au/Fish%20Farming.html/. (accessed April 2016)

Guerriero, K. 2011. Barramundi the Sustainable Sea Bass. Australis The Better Fish Aquaculture LLC. One Australia Way, Turners Falls, MA. Available: http://www.thebetterfish.com/the-healthy-fish/. (accessed April 2016)

International Game Fish Association. 2016. Barramundi Record. 300 Gulf Stream Way, Dania Beach, FL 33004. Available: https://www.igfa.org/species/80-barramundi.aspx?CommonName=80-barramundi.aspx/. (accessed April 2016)

Nichols, P.D., Glencross, B., Petrie, J.R., Singh, S.P. 2014. Readily Available Sources of Long-Chain Omega-3 Oils: Is Farmed Australian Seafood a Better Source of the Good Oil than Wild-Caught Seafood? NCBI. (accessed April 2016)

Rabanal, H. R. 1988. History of Aquaculture. Fisheries and Aquaculture Department, Organization of the United Nations. Tigbauan, Iloilo, Philippines. Available: http://www.fao.org/docrep/field/009/ag158e/AG158E01.htm/. (accessed April 2016)

Stein, Z. P. Holowko. 2016. Osmo Systems. OsmoBot Hydro Systems. Available: http://www.osmobot.com/models.html/. (accessed April 2016)

Thorne, N. 2011. Barramundi. Native Fish Australia (NFA). Victoria, Australia. Available: http://www.nativefish.asn.au/barramundi.html/. (accessed April 2016)

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