Changing Planet

First tuna farm in U.S. approved by Hawaii regulators

A Hawaiian company’s plan to raise millions of pounds of sashimi-grade tuna in giant “environmentally friendly Oceanspheres” two miles off Hawaii’s Big Island has been approved by state regulators, the company confirmed today.

The state Board of Land and Natural Resources voted last week 4-to-1 to give Hawaii Oceanic Technology permission to install three large underwater cages for the tuna, the Associated Press reported. “But the board is requiring the company to return for permission to build an additional nine cages once it has demonstrated the idea works,” AP said.


In an artist’s conception, Oceanspheres are suspended in the open sea. Each 162-foot-wide (49-meter-wide) aluminum-and-Kevlar cage would be completely untethered to the ocean floor and self-powered by a system that converts the ocean’s thermal energy to electricity. The spheres lie about 65 feet below the ocean surface, and the company says they are designed so as not to be a hazard to whales, sharks, or other marine life.

Illustration of oceanspheres courtesy of Hawaii Oceanic Technology

Twelve Oceanspheres will be deployed incrementally over four years, if permission to install all of them is given. Together they would have an annual production capacity of 6,000 tons of tuna, which the company plans to sell primarily to the U.S. mainland and Japanese markets, where prices are highest.

“The company has designed a system that will have no significant impact on the ocean and surrounding environment,” Hawaii Oceanic Technology said in a recent news statement. “To do this, the company is building very large submergible fish farming platforms…that adapt technologies from the defense, oceanographic and the offshore oil drilling industries to raise large amounts of seafood in an environmentally responsible manner,” said Chief Technology Director, Paul Troy.


Illustration of oceanspheres courtesy of Hawaii Oceanic Technology

“We are reducing the carbon footprint associated with producing seafood by using renewable energy technology and state-of the-art telecommunications techniques to maintain our Oceanspheres in very deep water away from the shoreline in geostatic position,” Troy said. 

When fully operational, the 12 Oceanspheres will operate in 247 ocean acres producing the 6,000 tons of Bigeye tuna per year. “More than 21,000 acres of land would be needed to produce the same amount of beef protein,” Hawaii Oceanic Technology CEO Bill Spencer said. “By taking advantage of all three dimensions of the ocean, we can be more efficient while using just a tiny speck of ocean when compared to the area of the vast Pacific,” he said.

“Hawaii is the only state in the U.S. that has an ocean lease regulatory framework that allows a company like ours to lease an ocean column for the purpose of fish farming,” Spencer added. “Our goal is to demonstrate that you can move some types of fish farming out into deep water where larger farms can be constructed and environmental impact can be insignificant due to naturally occurring processes.”


Illustration of oceanspheres courtesy of Hawaii Oceanic Technology

Fingerlings will be grown in land-based tanks at the Pacific Aquaculture and Coastal Resource Center in Hilo and/ or a future Natural Energy Laboratory Hawaii Authority tuna hatchery in Kona from eggs collected from locally-caught broodstock.

About seven additional tuna would be caught each year in local waters to freshen the gene pool of the captured broodstock, the company said.

The 12-inch, 5-pound fingerlings will be transferred by vessel to the Oceanspheres, and grown to 100-pound harvest size using dry fish feed through automated feed dispensers.

The land base for operations and maintenance equipment, vessels, and staff will be Kawaihae Commercial Harbor. Tuna will be harvested at sea for transshipping through Kawaihae or Hilo Harbor to existing processing and packaging vendors for air-freight to US mainland, Japan, and Hawaii markets.


Forty years in U.S., UK, and South African media gives David Braun global perspective and experience across multiple storytelling platforms. His coverage of science, nature, politics, and technology has been published/broadcast by the BBC, CNN, NPR, AP, UPI, National Geographic, TechWeb, De Telegraaf, Travel World, and Argus South African Newspapers. He has published two books and won several journalism awards. He has 120,000 followers on social media. David Braun edits the National Geographic Society blog, hosting a global discussion on issues resonating with the Society's mission and initiatives. He also directs the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship, awarded to Americans seeking the opportunity to spend nine months abroad, engaging local communities and sharing stories from the field with a global audience. Follow David on Facebook  Twitter  LinkedIn
  • trond lysklaett

    helo this is great

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