Former commercial fisherman Bren Smith suffered an attack of conscience and has given up his occupation in order to … create farms in the ocean. He talks about it with NewScientist (29 April 2017):
What is 3D ocean farming, exactly?
It’s farming that utilises the whole coastal water column, from top to bottom, so a lot is produced in a relatively small area. Thimble Island Ocean Farm, my original farm in Connecticut, goes down to 6 metres, but the 3D ocean farming model can work in anything from 3 to about 25 metres of water. Seaweed, particularly sugar kelp, and mussels are grown on ropes hanging in the water above oyster and clam cages (see diagram). One acre of sea can produce between 10 and 30 tonnes of sea vegetables and 250,000 shellfish every five months. We catch a few fish, too. Nutritionally, ocean plants like seaweeds are just as healthy and often healthier than land-grown foods. And bivalves are a source of lean protein that grows quickly.
What is so good about farming in water?
First off, you don’t have to fight gravity, so all you need is cheap but strong underwater infrastructure. An ocean farm is easily tended from a boat and doesn’t require the expensive inputs needed by most aquaculture and land-based farms. Crucially, we don’t have to feed or water “crops” once we seed them. Being in coastal waters means they often benefit from the nutrient-rich run-off from fertilised land farms. And the farms are visually low impact, with just some buoys visible above the water.
You call your farms “restorative”. Why?
Kelp is among the world’s fastest growing plants, so it could absorb large quantities of carbon from the atmosphere, making it the perfect crop for helping to mitigate climate change. And each oyster can filter 50 gallons of water a day. Many aquatic ecosystems suffer from excessive nitrogen, mostly from fertiliser from industrial farms. Shellfish pull that nitrogen out of the water. And we’re not catching many fish, so vertical farms become artificial reefs, havens for hundreds of species. Finally, the farms are strong yet flexible, helping to protect the coastline from storm surges.
Source: Screen scrape from GreenWave.org.
Remind me not to eat the oysters.
Trying to retain my alleged contrarian attitude, I can’t help noticing he hasn’t really broken his most basic orientation – exploitation of the the resource. Rather than work for, say, protection of a specific area of the ocean from human exploitation, he’s simply found a different way to do it.
And, given our hideous over-population, it’s not surprising. I’m not sure any productive area of the planet can NOT be exploited for human purposes, given the pressures inherent in population and human drives. So I suppose he can justify his work on the theme that a few highly productive areas will permit the balance of the ocean to proceed relatively naturally, in the classic (i.e., humans are not part of the natural order – which is sheer nonsense, but the concept does exist and has some usefulness in the form of expression) sense, with only a little bit of human intrusion.
Although I’d still like to see a concerted effort to remove shipwrecks from the sea.
Bren’s organization is named GreenWave. From their flowchart:
Zero Input Farming
The crops we grow require zero fertilizers, freshwater, or antibiotics, making 3D ocean farming the most sustainable form of food production on the planet.
I don’t doubt they mean well. I just have to wonder about their methods, philosophically speaking.
