As the planet’s population continues its growth towards 9 billion people in the next few decades, food production needs to shift into full-speed-ahead mode.
This includes more non-traditional, reusable water-based farming.
“We will need all forms of food including those grown through aquaculture, aquaponics, saltwater farming, plus growing edible seaweed,” says Kevin Fitzsimmons, veteran fish farming researcher and director of the University of Arizona’s (UA) Office of International Agricultural Programs.
“Integrating aquaculture with irrigated agriculture will be a worldwide growth operation.”
Global fishery decline
According to Fitzsimmons, “The popularity of aquaculture increased in the 1970’s with a wake-up call that global fisheries were declining due to unsustainable trawling and species over harvesting.
“Rather than wait until trawler run nets come up empty, we’re at a point now where the industry is changing.”
In 2012, more fish were farmed around the world than beef, Fitzsimmons says. More than half of the world’s seafood supply is now farm raised.
“Aquaculture represents a new food frontier,” Fitzsimmons said.
More fish than animals
The United Nations Food and Agriculture Organization reports the aquaculture industry is growing three times faster than land-based animal operations. Aquaculture may become more prevalent as natural fisheries become further depleted.
“It just makes sense to grow fish (or oysters or shrimp) in farm ponds before we use nutrient-rich water to further irrigate field crops,” says Fitzsimmons.
“Raising fish and plants together creates mutually-beneficial ecosystems with a focus on food production,” the UA leader said. “I’d like to see agriculture all over the world integrate with aquaculture to use the same water twice.”
With water already precious in the drought-plagued Western U.S., fish farms utilizing the dual production concept are becoming more visible.
Arizona, California aquaculture
About 30 aquaculture entities are licensed by the Arizona Department of Agriculture. More than a third of those are certified as fish farms.
In California, the California Department of Fish & Wildlife reports 120 fish hatcheries and preserves with the largest in Riverside County town of Mecca. The operation has 100 high-density concrete tanks which yield 40 tons of young fish weekly.
The Kent SeaTech Corporation in Temecula, Calif. is the world’s largest hybrid striped bass farm, sporting an inventory of three million fish with $10 million in annual sales.
“It’s been interesting to watch the aquaculture concept literally burst into flames with this region of the West becoming a hot spot,” said Fitzsimmons.
“We have clusters in Southern Arizona, Southern California, Baja California, and down the Sonoran coast with tilapia, hybrid carp, white bass, shrimp, tuna, and sturgeon farms.
He added, “It’s a movement that is both local - and global -- at virtually the same time.”
California is one of the most diverse aquaculture states in the union, says Fred Conte, aquaculture specialist at University of California, Davis.
Conte said, “We (California) have both marine and fresh water projects - you name it and we grow it. We’ve reached maximum sustained yields out of the ocean and yet the demand for fish keeps increasing.”
Fresh water production in California - currently about 2,500-3,000 surface acres of pond culture and a tremendous amount of tank culture - will remain fairly static until the drought breaks, Conte says. Off-shore marine production - if it develops - could be the largest area of expansion.
Aquaculture an arid farming fit
Fitzsimmons shares that aquaculture farming is a perfect fit for arid regions where controlled irrigation already exists.
“We can place cages in irrigation canals and reservoirs, run the water through the tanks, raceways, and then off into the field which gives us more crop for the drop.”
Use water for fish first - then crops
After spending time in Israel cultivating fish in an arid climate, this idea appealed to Brian Sternberg, owner of Maggie’s Farm, located on several dozen acres in the Southern Arizona desert in Marana (Pima County).
Maggie's Farm is an established grower of vegetables floating in water.
“We hear we’re the largest commercial aquaponics center in the state,” says grower Sandy Bales.
With successful growing runs of tomatoes, lettuce, kale, bok choy, and other seasonally-changing veggies, Sternberg introduced a separate piscatorial production facility a year ago to raise Blue and White Nile tilapia.
According to Bales’ son Joseph, “The ecological footprint of shipping fish around the country is staggering and unsustainable. Our cutting-edge urban fishery is about creating a local source of healthy fish with no mercury or additives.”
The operation is housed in a large covered structure holding eight tanks with a total of 80,000 gallons of water, plus 2,500 fish per tank.
“We do a one-time stocking of the tanks in March with a goal of 20,000 marketable fish for the season,” Bales said.
At one-year-old, each tilapia weighs 2-2.5 pounds.
“As a commercial venture, we have not proven a system of this size can be sustainable, but we’re three quarters of the way there hoping to move into the profit zone in the next year.”
Fitzsimmons and Conte concur that the future of food is fish and the future of fish is aquaculture.
They add that fish have a higher feed to ‘meat’ conversion ratio – 1.2 pounds of feed to 1 pound of product. This compares to a cattle-feed conversion rate of 10 pounds (feed) to 1 pound of beef. The ratio for pork is a 6-to-1 ratio.