CFER Project Title: The Ocean Drifter -- Fish Farming on a Global Scale
PI: Clifford Goudey, MIT Sea Grant

The Ocean Drifter - Fish Farming on a Global Scale
Project Overview
Page 1 | 2

Whereas conventional fish farming cages can only operate in the limited coastal margin where anchoring isfeasible, the Ocean Drifter can be used in vast areas of the oceans, where average depths exceed 6,000 meters. In these larger bays and ocean basins, predictable currents dominate. Some of these can be seen in Figure 3.

Click the image to view a full-size version.
Figure 3: The major ocean currents (from ONR).

It is these currents, driven by prevailing wind, the Coriolis effect, and temperature differences, that can be harnessed to usher in a more sustainable form of ocean-based aquaculture. By avoiding the contested and often polluted coastal margin, the Ocean Drifter can reduce the damaging effects of storms, while delivering its valuable, free-swimming cargo of fish to markets worldwide.

The May 2004 issue of Wired magazine describes the Ocean Drifter in its cover article:

Goudey views [coastal open ocean aquaculture] efforts as small prototypes. Backed by federal funds, he has begun work on an immense next-generation design, 174 feet tall and 270 feet in diameter, called the Ocean Drifter. Unlike its predecessors, which are fixed to the seafloor, this enormous cage will roam the seas, propelled by three electric thruster motors attached to the rig's steel equator. Powered by a diesel generator mounted atop the central spar and steered by software, it will venture hundreds of miles from shore. When the fish are big enough to sell, a specially designed ship will embrace the cage and hoist it aboard
.
" The ocean is full of predictable currents, or gyres," Goudey says. "If you could get the cage into one of these gyres, it would essentially stay in the same place, or at least have a predictable trajectory. Even if you had just a slight ability to adjust its movement, you'd be able to control its path pretty exactly." In his view, "you could build a fleet of these things in the Straits of Florida, fill them with fingerlings of, say, cobia, and let them follow the Gulf Stream for nine months until they reached their intended market in Europe with a harvestable crop. Then you'd load them up again and send them back along the southern route with another crop."

Interest has grown on this novel topic. Listen to a Fish Radio recently broadcast on 20 radio stations in Alaska. Play a program clip (mpeg3 format).

Of course, for true oceanic deployments, the Ocean Drifter operation must be large enough in scale to be economically viable. Fish farming requires substantial feed, and routine deliveries of such expendables must be provided on a regular basis. Whether manned or autonomous, a fleet of Ocean Drifters will require service ships to keep the cages supplied and properly maintained during its journey to market. Work is underway to examine the potential of specific ocean currents, the markets those currents could serve, and the species that could be cultured on route. CFER is building a multidisciplinary team to further develop Ocean Drifter and make progress towards a commercial-scale demonstration.

Wired article "The Bluewater Revolution"
http://www.wired.com/wired/archive/12.05/fish.html?pg=1&topic=
fish&topic_set=

Model Tests and Operational Optimization of a Self-propelled
Open-ocean Fish Farm (.pdf document)
Clifford A. Goudey, MIT Sea Grant. In: A. Biran, Ed. Proceedings Offshore Technologies for Aquaculture. Haifa, Israel, 13-16 Oct. 1998

Ocean Current map source:
http://geography.about.com/gi/dynamic/offsite.htm?site=http%3A%2F%2F
www.onr.navy.mil%2Ffocus%2Focean%2Fmotion%2Fcurrents1.htm

Page 1 | 2