Posts Tagged ‘sea cages’


Robotic Offshore Cages – The Future of Fish Farming?

November 24th, 2009 by Hayley
Aquapod© (Source: Ocean Farm Technologies)

Aquapod™ (Source: Ocean Farm Technologies, Inc.)

Sometime ago we posted about heading towards automation self propelled aquaculture cages. Since then, Cliff Goudey, director of the Massachusetts Institute of Technology’s Offshore Aquaculture Engineering Center, has been working on a project funded by the National Oceanic and Atmospheric Administration (NOAA), which is testing these cages with cobia farming operations in Puerto Rico.

Goudey has equipped an Aquapod™ cage, produced by Maine-based Ocean Farm Technologies, Inc., with a set of propellers, which act as big screws that churn their way through the ocean.

Self Propelled Cage (Source: www.wickedlocal.com)

Self Propelled Cage (Source: www.wickedlocal.com)

Goudey’s technology gives fish farmers a way to rotate cage locations without towing cages behind boats. The cages become mobile fish farms, making ocean depth less of an issue and fouled water quality and low dissolved oxygen content less of a threat by transferring the fish to areas of the ocean never before accessible to fish farming.

Working recently at Snapperfarm Inc., the cobia operation in Puerto Rico, Goudey’s cage has proved itself capable of moving on its own.

For footage of the sea trials in action click here to watch a video.

Click here for more information on this topic.


Large-scale fish farming in the Gulf of Mexico

February 3rd, 2009 by Hayley

In the Gulf of Mexico, there has been much interest in innovation towards transforming unused offshore oil and natural gas platforms into fish farms. Some oil companies have experimented with platforms to anchor underwater pens.

This week a crucial step in this process has developed.  Authorities have approved the ardently debated proposal to allow large-scale fish farming in the Gulf of Mexico, creating the first federal regulations for a fledgling industry.

Opponents have cited concerns about damage to the Gulf’s environment, as well the effect on traditional fishing communities that have relied on catching and selling wild fish.

But supporters say the industrial-scale pens and cages could provide a new source of seafood, 80 percent of which now comes from imports.

Commercial seafood company owner John D. Ericsson favours the plan. He said the United States has fallen behind countries like Greece, Norway and Chile, where offshore farming has taken off.

Ericsson said his company, Florida-based BioMarine Technologies Inc., is looking at growing fish in cages that could contain up to 60,000 cobia, also known as king fish, and amberjack. He said it would take about $10 million to set up an offshore fish farm.

Despite approval Wednesday from the Gulf of Mexico Fishery Management Council, a 17-member regional advisory body that sets fishing regulations in the Gulf, the fish-farming plan still faces a series of administrative hurdles, and needs approval from the National Oceanic and Atmospheric Administration and the U.S. Department of Commerce.

Officials who developed the plan say it will be at least a year before anyone could apply for an open-ocean aquaculture permit, even with the necessary approval.

More than 100 environmental and fishing industry groups have signed on against the fish-farming plan, and many say they are hopeful the new Obama administration will quash the measure or send it back to the Gulf of Mexico Fishery Management Council for revisions.

One of the main complaints has been that offshore aquaculture regulations should be developed by Congress on a national scale, rather than by a regional body such as the Gulf council.

The Gulf council’s plan calls for 10-year permits to set up offshore fish farms.

Officials set a total cap on farmed fish production at 64 million pounds, and they expect about five to 20 such operations to emerge within the next 10 years.

Drafters say they have addressed a number of ecological concerns in the plan: It requires an up-front environmental analysis from anyone applying for a permit, mandates the hiring of an aquatic animal health inspector, and lays out numerous record-keeping requirements regarding escaped or diseased fish.


Tensegrity: Bringing the Geodesic Dome to Aquaculture

November 13th, 2008 by Andrew

I recently came across the amazing work of R. Buckminster Fuller, a visionary architect, inventor, futurist, designer, author and the second president of Mensa. Among his many contributions was the 1949 construction of the first geodesic dome, a self-supporting tensegrity structure that harnesses a synergy between balanced tension and compression components.

Tensegrity structures are built up by combining compression members (e.g. rods or bars), under compression, and tension members (e.g. cables or strings), in tension.  This structural concept has been applied in civil engineering, structural engineering, architecture and aerospace engineering…and now, in aquaculture.

Norway’s SINTEF Marine are investigating the development of “smart” sea-cages for fish farming. Traditionally, designers have opted to ‘design in’ strength into marine structures so that they can withstand the forces of the ocean and extreme weather events. SINTEF are experimenting with a different philosophy of design, one that prefers adaptation and cooperation to raw strength.

In extreme weather events in open water, the use of tensegrity structures at the top of cages would significantly improve the stability of aquaculture cages and enable them to withstand severe environmental forces.

If necessary, a aquaculture sea-cage comprised entirely of tensegrity structures could change its own shape, so that it reduces the cross-sectional area that it presents to the waves. If there is little current and thus relatively little oxygen available to the fish, it will increase the area turned towards the direction of the waves.