Research Highlights
Soybean and Aquaculture Industries Growing Together

Soybean meal is a common food in the U.S aquaculture industry. Photo: Dr. Ganesh Kumar, Mississippi State University

By Carol Brown

Americans eat a lot of seafood — the United States leads the world in seafood consumption, although not per capita. But the country is not a leading seafood producer, as 90 percent of the seafood consumed in the U.S. is imported from other countries. The U.S. aquaculture industry is a long-standing supplier of fish and shellfish for generations of Americans, but it could be much larger.

“Aquaculture farms in the United States have been around for a century or longer,” says Carole Engle. “Farms have been raising trout and other species as well as bait fish and sport fish for decades. Catfish is the top species being farmed in the U.S. It’s the biggest by far.” 

Engle is an aquaculture consultant and retired director of the Aquaculture/Fisheries Center at the University of Arkansas–Pine Bluff. She continues to conduct research to help improve the U.S. aquaculture industry.

Aquaculture comprises all finfish — including food fish, ornamental fish, sport and game fish —as well as shellfish and crustaceans, raised in a controlled environment. Aquaculture farms are in every state, according to the U.S. Census of Aquaculture, which is recorded by the United States Department of Agriculture (USDA) and the National Agricultural Statistics Service (NASS).

Engle is the lead author of a report, “Potential Economic Value of Growth of U.S. Aquaculture to U.S. Soybean Farmers,” which is an outcome from soybean checkoff-funded research provided by the Soy Aquaculture Alliance. She and fellow authors explored the relationship between these two industries and how they could continue to benefit one another.

“This study addressed the questions, how much increased demand would there be for U.S. soybeans from growth of the U.S. aquaculture industry and what would be the benefits to the U.S. soybean industry and how much increased demand would there be?” she says. “I think It makes so much sense to be raising more of the seafood that we eat here in the U.S., from the perspectives of food security, local food supply chains, and rural community economic development.”

Soybean meal being fed to fish. Photo: Dr. Ganesh Kumar, Mississippi State University

Soybean meal is a key factor in the aquaculture industry. American soy products are high quality and preferred by feed mills that supply U.S. fish farms, says Engle. According to her report, total soybeans demanded in U.S. aquaculture in 2018 were estimated to be 8.6 million bushels with the U.S. catfish industry representing 89 percent of that demand. 

Soy Aquaculture Alliance Executive Director Kenlon Johannes supports Engle’s findings and agrees that the two industries need to stay intertwined.

“Our soybean farmer leaders see aquaculture as one of the next, great opportunities to expand and diversify our soybean meal market,” Johannes says. “As with any new, expanding market opportunity, we need to promote ourselves against our feed competitors as the best, most sustainable feed source for aquaculture. Soybean meal feeding trials, funded by the checkoff, help prove the quality and sustainability of our product to the end users, the aquaculture feed manufacturers, and fish farmers.”

According to the 2018 Census of Aquaculture, there are 530 catfish farms in the country, followed by 334 trout farms, with Mississippi as the leading state in catfish production.

“Farmed catfish have been fed soybean meal for the last 30 to 40 years,” says Engle. “Decades ago, nutritionists found they could substitute soybean meal for fishmeal as a protein source for catfish and they grew just as well. For catfish, tilapia and some other species, the major ingredient in their diet is soy.”

Engle points out a mistaken belief that fish can’t digest soybean meal. She says the digestibility of soybean meal depends largely upon the fish species. Soybean meal makes up about 35 percent of catfish and tilapia diets. Although there are some species that do not digest soy as well as catfish, research is leading to promising ways of improving soybean meal digestibility for trout, salmon, and other species including marine fish.

Catfish soybean usage in diets is greater than it is in terrestrial livestock. Poultry and hogs are fed a diet comprised of 28 and 18 percent soybean meal, respectively, as stated in Engle’s report. Thus, for every ton of feed fed to catfish, more soybean meal is used than for poultry, hogs or other livestock.

Table 1. Percentages of Various Livestock Diets That Are Composed of Soybean Meal.
Source: Decision Innovation Solutions 2018

Therefore, increasing total production from the catfish industry alone has the potential to increase soybean demand significantly. If the catfish industry could return to the size at its peak in 2003, its demand for soybeans would nearly double, Engle says. Similarly, growth of other U.S. agriculture sectors will further increase U.S. soybean demand.

Figure 1. Volume of production of U.S. Catfish (in lb), 1981 to 2018. Source: Catfish Reports, The Catfish Institute

“This is an opportunity for soybean farmers to gain a foothold in this ever-expanding industry,” Johannes says. “With seafood1 now surpassing pork as the number one animal protein source for humans worldwide; and the oceans and other water resources slowly being depleted of this resource, the world will need to rely on aquaculture as a major source of fish and shrimp.”  

But there are a few hurdles to overcome. Engle says the country’s aquaculture industry is not on a level playing field with imported products.

“The production costs of catfish and other finfish in the U.S. are higher than those from fish imported into the country. The costs are higher here because the fish are raised in environmentally sustainable ways,” comments Engle. “U.S. fish farmers pay to clean up water and reduce fish waste before discharging into receiving waters and our products are held to high food safety standards on levels that are not matched in many of the countries that export to the U.S.”

As with any soybean checkoff funded activity, Johannes says, if U.S. soybean farmers don’t try to capture this expanding market for soybean meal, it could be a major opportunity for feed competitors.

“If we support the finfish industries to grow in volume, more soybean meal will be used,” Engle says. “If we can also increase soybean meal inclusion rates in aquaculture through continued research advances, growth will be increased even further for both aquaculture and soybean industries.” 

Read Engle’s report at the Soy Aquaculture Alliance website: https://www.soyaquaculture.com/research-reports

Read the 2018 Census of Aquaculture: https://www.nass.usda.gov/Surveys/Guide_to_NASS_Surveys/Census_of_Aquaculture/index.php

1 FAO. 2020. The State of World Fisheries and Aquaculture 2020. Sustainability in action. Rome. Table 16, page 70.
https://doi.org/10.4060/ca9229en

This project was funded by the soybean checkoff. To find research related to this research highlight or to see other checkoff research projects, please visit the National Soybean Checkoff Research Database.