Florida Research Leads the Way
Imagine a world where every neighborhood had tanks filled with recirculating seawater big enough to grow plenty of fresh, sustainable seafood for every meal of the day. Sound too good to be true? Read on.
From its humble beginnings as a two-person research team in a tiny Florida lab, an independent nonprofit known as Mote has become a leading marine research facility with more than twenty research projects under its umbrella.
As the Sarasota-based Mote Aquaculture Research Park celebrates its twentieth anniversary in sustainable aquaculture research, we spoke with Mote Marine Laboratory & Aquarium to find out about an especially exciting project: a system that could provide fresh, local, sustainable seafood to most inland spots on the globe.
A new twist on aquaculture
Over the years, Mote’s research taught them a lot about aquaculture, the fish-farming practice that’s been around for centuries. Now Mote is adding a sustainable twist to its aquaculture—it is using large tanks about twenty miles inland from the Gulf of Mexico to grow both fish and sea vegetables.
Dr. Kevan Main gets us started on the basics behind Mote’s unique research. Dr. Main is Mote’s associate vice president for research, program manager for marine and freshwater aquaculture research, and senior scientist. “Aquaculture is something that people don’t really understand very well. It is the same thing as agriculture: It’s the farming of animals or plants in water,” she says.
Adds Mote’s public relations manager, Stephannie Kettle, “Aquaponics, which combines aquaculture and hydroponics, is simply growing fish and plants in water.”
But Mote does aquaponics differently. Mote uses recirculating seawater in land-based tanks, and while most aquaculture projects of this nature grow freshwater fish together with agricultural crops, such as lettuce, Mote made the pioneering decision to raise marine fish species together with sea vegetables.
The secret is in the system
How does their recirculating sustainable system work? Kettle explains: “Water in the fish habitat is filtered and cleaned and then run through the plant system before returning back to the fish system. The fish waste is utilized by the plants.”
When asked what makes a recirculating system clean and sustainable, Kettle adds: “As plants are able to use fish waste as ‘food’ and the plants assist in filtering water, the fish are consistently provided [with] clean water.”
And how long does it take the water to recirculate? Depending on the system in use, water “turns over," which means it is filtered and runs through the entire system, in just one to three hours.
Mote confirms that some seawater is lost during the process, via uptake by plants and evaporation, and does need to be replaced. However, their research team continues to drill down on how to minimize water use and filter it so that it can be reused repeatedly.
“We have been able to prove that an inland seawater recirculating system is possible,” Kettle says.
Why does Mote do this?
As a sustainable aquaculture technology developer, Mote first pioneered its innovative aquaculture method to help secure the globe’s food needs and replenish depleted species. It also aims to contribute to a viable domestic aquaculture industry in the US.
“To ensure a stable supply of quality protein, and to lessen the impacts on wild fish populations, sustainable, recirculating aquaculture systems are a necessity,” Kettle explains.
To meet the United States’ increasing demand for seafood and to restock depleted recreational and commercial stocks, Mote’s researchers are also developing spawning, larval, fingerling, and grow-out culture methods for marine or freshwater species.
“We really focus on trying to unlock the methods, the mysteries of how these animals are able to reproduce or grow in nature and try to make that environment here in the laboratories,” says Dr. Main, detailing Mote’s research.
What are they growing in those tanks?
Mote’s research team is focused at this time on growing marine finfish, as well as marine shellfish. On the plant side of the system, they raise marine vegetation such as sea purslane or mangrove trees.
Marine species that are native to the Gulf of Mexico, including almaco jack and redfish, are Mote’s primary focus. “These are fish that are tasty and for which there is an existing market,” says Kettle.
Advanced spawning and rearing technologies have been deployed by Mote to analyze a wider variety of species, as well, including common and Pacific snook, Florida pompano, southern flounder, greater amberjack, red drum, red snapper, zebrafish, abalone, shrimp, hard corals and long-spined sea urchins.
“The species we work with the most is the common snook, which is not produced or fished commercially. We grow common snook juveniles for habitat restoration purposes,” says Kettle. Snook are sensitive to environmental threats such as cold stun and red tide events. Commercial fishing for snook is prohibited due to past population declines.
“Common snook is extremely valuable as a driver in the sportfish/tourism industry,” Kettle says. Mote’s task is to grow and release juvenile snook to increase their populations in the region.
Sea vegetables, otherwise known as sea purslane, are also a species of focus. “Sea purslane grows well in an aquaponics system, has good nutritional value, and is a tasty, not-too-salty addition to many dishes,” Kettle says. (Mote is coming out with a sea purslane cookbook.)
Is there commercial interest?
For commercial operations, a key question has to be whether tank-raised fish compare in taste and quality with wild-caught fish?
Kettle explains: “Aquaculture-grown species are especially valuable to restaurants that are looking for consistent fish products to create their menus around—the supply is consistent and not seasonal, and fish are grown to a consistent, desirable market size.”
“Fish in aquaculture systems are fed carefully selected diets and do not face the same stress as wild fish (for example, having to hide from predators, seek food, seek shelter, seek mates). Their lighting and temperature conditions are also optimal,” says Kettle. “This results in a quality fish product that is extremely consistent.”
A study conducted by Mote’s researchers and supported by the Gulf Coast Community Foundation found that seafood farmers can raise fish successfully on a diet of wild-caught mullet, a plentiful fish in Florida’s waters. The nutritional findings of their study indicate that feeding with mullet can improve the sustainability of seafood farming and add value to fisheries, which it did for a major Florida fishery.
“We saw a unique opportunity to transform a locally available by-product—excess mullet from the fishery in Cortez, Florida—into a valuable fish meal product that could be used in commercial aquaculture feeds,” Dr. Main says.
In terms of profitability, Mote’s recirculating technology solves a couple of major headaches for farmed-fish producers. It provides a solution to the rising coastal property costs and the regulatory constraints attached to production that pressure Florida’s shifting and challenging aquaculture landscape.
“We regularly communicate with others in the industry, including other researchers, local restaurateurs and chefs, state and federal agencies,” says Kettle.
Commenting on the impact that its model may have on commercial applications, Kettle says: “We hope that our aquaculture research projects can show how recirculating seawater systems can create a sustainable, reliable source of quality protein.”
Getting the message out to global producers is crucial. “Over 90 percent of the seafood that is coming into this country [the United States] is raised in some areas of the world that don't have the highest standards of environmental controls,” says Dr. Michael P. Crosby PhD, president and CEO, Mote Marine Laboratory & Aquarium. “It calls into question not only the quality of the seafood that we are bringing in but also the impact of those aquaculture operations around the world,” Dr. Crosby says.
Looking ahead, Mote’s research will center on growing salable products, incorporating alternative energy into system designs to boost the sustainability and economic feasibility of recirculating systems, and further developing sustainable marine aquaculture.
With inland fish farming in tanks on the rise and with Mote leading the way, the global availability of fresh, local, sustainable seafood is increasing.
“The world population is growing. The only way we are going to be able to feed that ever-growing population is through aquaculture,” Dr. Main says. What Mote’s research is creating, she says, is “aquaculture for the 21st century.”
*Natasha Spencer-Jolliffe is a freelance journalist and editor. Over the past 10 years, Natasha has reported for a host of publications, exploring the wider world and industries from environmental, scientific, business, legal and sociological perspectives. She has also written for market intelligence companies like Innova Market Insights and WGSN. Natasha has also been interviewed herself as an insights provider for research institutes and conferences.