Q&A: Is RAS the next step for aquaculture?
Aquaculture has been the fastest-growing segment of global food production for a number of years now and doesn’t show any signs of slowing down. Michael Timmons, a professor of biological and environmental engineering at Cornell University in Ithaca, N.Y., talks about the promise of recirculating aquaculture systems (RAS) how they can be the answer to the downfalls of traditional aquaculture production.
Editor’s note: RAS is detailed in the text titled, “Recirculating Aquaculture, 2nd Edition,” written by Timmons and James Ebeling and published in 2010. The text is available in English and Spanish. Visit www.c-a-v.net for details.
What is the difference between RAS and traditional aquaculture?
Indoor RAS offers the advantage of raising fish in a controlled environment, permitting controlled product growth rates and predictable harvesting schedules. RAS conserve heat and water through water reuse after reconditioning by biological filtration using biofilters. RAS allow effective economies of scale, which results in the highest production per unit area and per unit worker of any aquaculture system. RAS are environmentally sustainable; they use 90 to 99 percent less water than conventional aquaculture systems, less than 1 percent of the land area and provide for environmentally safe waste management treatment.
Do you feel interest in RAS is accelerating?
We have taught a one-week short course on this topic continuously for 17 years; the number of students taking the course has not changed over this time (20 to 40 students each year from the North America and all parts of the world). Standards of living in the developing countries continue to climb, with the result being that more of their aquaculture production will be retained in-country. Since the U.S. imports approximately [85 percent] of its seafood, there will be more demand for product that will drive prices up. Higher prices will allow RAS to more effectively compete in the U.S. market.
Why it is becoming more popular?
RAS allows the production of seafood in an environmentally sustainable approach. Only RAS can truly guarantee the factors affecting the quality and safety of the product.
What are the benefits of RAS?
Fundamentally, RAS allows economical control of water quality parameters so that the environment can be maintained at optimum conditions for the reared species, 24/7, 365 days of the year. RAS allows our aquaculture industry to move in the direction of other animal production systems where controlled management/housing produces maximal economic efficiency, which in turn can be passed partly back to the consumer.
What is the cost difference? And do you see that changing as it becomes more prevalent?
We have developed cost competitive technology vs. other conventional forms of aquaculture (ponds, net pends, flow through systems). Our key to low cost production is minimizing the energy (pumping) to maintain water quality. Increasing scale of the systems reduces labor costs. Fish are the most efficient converters of feed to flesh among all our meat alternatives. Fish can be produced for 50 percent of the feed input necessary for a broiler chicken, which is the most efficient warm-blooded animal.