To feed an ever-growing world, scientists are working on sustainable ways to produce protein, and land-based aquaculture has become an increasingly viable way to build a sustainable seafood system. The U.S. Department of Agriculture (USDA) recently awarded $10 million to support the Sustainable Aquaculture Systems Supporting Atlantic Salmon (SAS2) program, a U.S./global partnership between academia and industry to foster the development of environmentally sustainable and economically feasible Atlantic salmon farming in the U.S.
University of Maryland Center for Environmental Science Professor Al Place researches sustainable aquaculture practices, searching for solutions to supply limitations of fish feed in current industry standards. With this grant, he will research developing environmentally responsible feeds for the salmon stock and ensuring optimal fish quality, particularly taste.
“For me the interesting aspect of this research deals with the big issues of life. How will we feed 11 billion people on this planet? We know of no other production system where you can put a pound of food in and get a pound out. It’s not true for chicken and cows. In principle, aquaculture can produce sufficient food and protein to sustain the planet,” said Al Place.
The project will be led by Yoni Zohar, UMBC professor and chair of marine biotechnology working at the Institute of Marine and Environmental Technology (IMET), who has made steady progress toward making large-scale, sustainable land-based aquaculture—raising fish on land—a reality. The SAS2 program includes several academic and federal research institutions, including the University of Maryland Center for Environmental Science, and nine industry partners from across the U.S., plus partners in Iceland and Norway.
It’s an exciting time for aquaculture, I’m looking forward to seeing all the great things that are going to come out of this over the next five years.
Feeding a growing planet
SAS2 will address the major challenges for Recirculating Aquaculture Systems (RAS), land-based salmon farms, in which the operation is entirely inside a large building where fish are grown with virtually zero waste. In collaboration with major U.S. producers of these innovative systems, leading aquaculture scientists will carry out research focusing on current impediments to the expansion of this industry, including egg production, ecologically-responsible and efficient feeds, increased water re-use, minimized waste, improved product quality, and economic analyses.
“The mission is to enable an innovative, effective, and sustainable U.S. Atlantic salmon production platform that will transform the U.S. food and aquaculture systems and secure and increase high-quality and affordable seafood production for the world,” said project leader Yoni Zohar, director of the Aquaculture Research Center at the Institute of Marine and Environmental Technology (IMET).
The standard method in aquaculture is to house fish in large pens in the ocean. Excess waste from the fish is dumped into the ocean, introducing excess nutrients and natural parasites to the water. Moving operations on land allows facilities to monitor and control environmental factors and for a complete recirculating water system. An astounding 95% salmon consumed in the U.S. are imported and current coastal floating salmon pens are not able to expand due to strict environmental regulations.
Land-based aquaculture systems are self-contained, avoiding the risks of environmental pollution or farmed fish escaping and interbreeding with wild stocks. They can be built anywhere, reducing the carbon footprint and cost of transporting fish. The water composition (salt and other minerals) can be optimized for different species, based on their natural habitat. Controlled light and temperature cycles ensure optimal year-round fish performance and production and allow spawners to breed at different times of year, resulting in fish coming to market size year-round.
“There is a big movement to move things on land where you can control everything,” said Place. “It’s a higher cost to start up to build tanks, but you have much more control over everything.”
A New Food for Fish
Place has been a world leader in research to replace the practice using fish meal to grow fish for human consumption, which requires overharvesting the oceans of small fish to feed and grow larger fish. He has been able to replace fish meal completely using a combination of soy, algae, and other additives. Now he is working on using insect meal to replace the soy protein, which can cause inflammation problems in the fish.
“Growing insects is a very sustainable protein source. It’s taking the pressure off the fisheries. We no longer have to harness menhaden or other protein source,” said Place
Switching to an insect-based diet would not only decrease the pressure on wild-caught fisheries, but research has shown that insect diets can be used to positively manipulate the gut health of fish, which can also improve their immune system.
He is also addressing the problem of an off flavor being caused by two molecules that can make fish produced in land aquaculture smell like soil. “People don’t like that in their fish, and we have no idea why this is showing up in the system,” he said.
Along with the laboratory of Professor Jacques Ravel, Associate Director, Institute For Genome Sciences at the University of Maryland School of Medicine, they will be using molecular forensics to find the bacteria that produces the off flavor by swabbing and taking DNA samples from the tank, the walls, the filters, to identify where molecules are being made.
“In the long term we will look at bacteria phages, viruses that will kills the producers, so can we isolate a phage that will target producers of the bacteria,” he said.
Ensuring products produced by on land aquaculture centers are of the best quality and taste can encourage investors, consumers, and other scientists of the potential these sustainable farming facilities. As demand for seafood continues to rise, innovative systems like this pave the way for producing a much greater quantity of seafood in a more sustainable way.
