Researchers work to find strategies to produce seafood

John Stieglitz, assistant research professor of marine biology and ecology, holds a small portion of the 40 day old juvenile yellowtail snapper that he is raising as part of a grant to determine the viability of raising these fish in captivity. Photo: TJ Lievonen/University of Miami
By Janette Neuwahl Tannen

John Stieglitz, assistant research professor of marine biology and ecology, holds a small portion of the 40 day old juvenile yellowtail snapper that he is raising as part of a grant to determine the viability of raising these fish in captivity. Photo: TJ Lievonen/University of Miami

Researchers work to find strategies to produce seafood

By Janette Neuwahl Tannen
The Rosenstiel School’s growing Aquaculture Program trains students to cultivate high-demand fish using techniques they develop and refine at the Experimental Fish Hatchery.

Early one morning last spring, a few University of Miami students peered down into a massive circular tank as John Stieglitz, a research assistant professor, used a small net to skim the surface of the water.

The group marveled at the wonder before them. Floating near the surface were fertilized yellowtail snapper eggs. Hundreds of thousands of them.

Stieglitz quickly transferred the tiny spherical embryos to a small incubation tank for hatching; and soon after, he moved the young larvae to a larger tank. That is where they would be grown to juvenile-size fish, approximately the length of a human finger.

It was just the beginning of a two-year research project to investigate whether yellowtail snapper can be raised in aquaculture facilities for commercial fish markets.

The yellowtail snapper is just one of nearly 10 different species, including flounder, mahi-mahi, red snapper, cobia, almaco jack, Nassau grouper, hogfish, and even stone crabs, that Stieglitz and Daniel Benetti, the Aquaculture Program director, are working with at the Rosenstiel School of Marine and Atmospheric Science. In the program, graduate and undergraduate students, along with Benetti, Stieglitz, and others, work to find the most cost-effective and environmentally sound methods to raise seafood in aquaculture facilities and then share the knowledge within the industry.

“We want to play a leading role in the development of sustainable seafood,” said Stieglitz, who teaches in the Department of Marine Biology and Ecology. “And we are focusing on the most desirable marine fish species with the greatest potential to advance this industry in the United States and to reduce our reliance on wild fish stocks and imported seafood.”

As the world’s human population continues to rise, and wild fish stocks decline, the aquaculture industry is rapidly expanding to meet a growing desire for fresh seafood. Today, more than 55 percent of the seafood that people eat is grown in aquaculture facilities, and most of the fish consumed in the United States comes from other countries, according to Benetti, who is also a professor of marine biology and ecology. Across the world, it is clear that people love fish because 3 billion people rely on it as a principal source of protein, Benetti added.

“This is the fastest growing sector of food production in the world,” said Benetti. “And the U.S. is lagging behind [in aquaculture]—more than 90 percent of seafood consumed in America is imported and 80 percent of that is farmed.”

A desire to improve and refine aquaculture practices at a time when the U.S. industry is taking off underpins the entire program, Benetti noted. Stieglitz and Benetti  have built strong relationships with successful aquaculture companies across the globe and are using that knowledge to guide their research.

“We are known for developing cutting-edge technology to produce wholesome, sustainable seafood,” said Benetti, who has led the program for 23 years. “This will help feed the world into the future.”

While the Aquaculture Program began in 1968 with a focus on two species—pompano and shrimp—today its Experimental Fish Hatchery, managed by program alumnus Ron Hoenig, continues to add new types of fish with support from public and private grants. This variety piqued the interest of Gabriel Jimenez, a master’s-degree candidate who worked at the Harbor Branch Oceanographic Institute at Florida Atlantic University before pursuing his graduate degree at the Rosenstiel School.

“What’s fun about aquaculture is each species has very different needs,” Jimenez said. “I’m now working with seven species at a time that can all be grown in the United States, to decide what species I want to work with in the future.”

Another benefit of the program’s research is that it can help support the local fishing industry. In recent years, fishing quotas for yellowtail snapper have been met early on in the season. And in the case of flounder, the quantity of available fish off the coast of the Atlantic states has declined, leaving fisherman without a steady income. Such disruptions can cause negative impacts that extend throughout entire working waterfront regions, Stieglitz pointed out.   

“We want to provide the technology through aquaculture to fill this gap between supply and demand of fresh seafood in the U.S., while offering opportunities for increased resilience in working waterfront communities,” Stieglitz added. “Aquaculture facilities could offer an alternative for the fishing communities when quotas are closed and help diversify their income.”

The researchers are also looking at ways to extend the shelf life of both wild-caught and farm-raised fish like yellowtail snapper, so that people beyond the southeastern United States can enjoy the tropical species.

“It’s not simply about producing fish for the table, but we’re also working on improving the value that fishermen receive from their catch,” Stieglitz said.

While a sizeable grant from the National Oceanic and Atmospheric Administration (NOAA) Saltonstall-Kennedy Program is supporting the yellowtail snapper project, Stieglitz is also working on cultivating the olive flounder, a fish native to Korea and Japan also known as “hirame.” The fish is often used for sushi, and it is very similar in taste and texture to the species of wild flounder that is caught and consumed along the eastern seaboard of the U.S. But it is getting harder for fisherman to catch.

“A number of groups have expressed interest in growing this species commercially, so we are doing a pilot-scale study to grow the olive flounder [at our Experimental Fish Hatchery] and to learn what the cost of producing this fish would be at different scales,” Stieglitz added, noting that the project is supported by funds from NOAA’s Atlantic States Marine Fisheries Commission.

Simultaneously, the program is also working on a new project focused on the Almaco Jack, a fish often found in the Gulf of Mexico and southern Atlantic Ocean. The grant aims to support the development of a U.S. aquaculture industry around the Almaco Jack and other warm water marine fish species, Stieglitz indicated.

“We are trying to optimize the production process of this species using advanced scientific methodologies to find the most efficient ways to grow them,” he added.

Because their research is pragmatic and typically leads to applied strategies for cultivating fish, the Aquaculture Program also maintains close relationships with government and industry leaders who have also played a major role in the program’s expansion. These outlets offer insight about where new research is needed and fund many of the program’s pilot projects. For example, one of the more successful fish species that the program has worked with is cobia, as a result of an instrumental research agreement with Cuna del Mar, the parent company for Open Blue Sea Farms. It has aquaculture facilities off the coast of Panama, where several alumni work today. In addition, NOAA’s Sea Grant has also been a critical boost to the program for many years, Benetti noted.

As an indication of how aquaculture is flourishing, nearly all of the program’s graduates find a job in the field, and many have even founded their own companies. Six of the program’s alumni currently work at Atlantic Sapphire, a massive land-based aquaculture facility growing salmon in Homestead. Another alumnus, Aaron Welch, founded Two Docks Shellfish with his father after completing his master’s degree through the Aquaculture Program and earning his Ph.D. in ecosystem science and policy. Another group of alumni work in Hawaii at Blue Ocean Mariculture.

“Our network is remarkable, and the level of recruitment from our graduate program is unparalleled because people know that our graduates are well-trained,” Benetti said. “Also, since we have more than 150 alumni working in the industry—at research organizations, in government, and in academics—we are directly or indirectly involved in aquaculture initiatives throughout the world.”

And as the aquaculture industry evolves, so does the program’s research. Faculty and staff members, as well as students with experience in offshore aquaculture facilities abroad are working with state and federal officials to assist with development of a pilot project in the Gulf of Mexico, while also continuing to perfect strategies for growing fish that consumers prefer. Others are helping to understand whether releasing juvenile fish into the wild are useful to increase wild fish populations, while some students are working to investigate the best types of nutrients to feed fish raised in captivity.

“We are helping to train the next generation of aquaculture professionals, and the University of Miami is leading the way in doing that,” Stieglitz said. “This is the future of seafood, and our research helps to advance the sustainability of the industry as a whole.”

Learn more about earning a graduate degree in aquaculture.