Mainly due to Covid travel restrictions, I still haven’t visited any of our customer’s fish farms. Salmon aquaculture is a large industry in Norway. Many fish farms can be found in Norway’s inlets. With Google maps, I can take an aerial tour.

Three circular fish pens are connected to a barge that supplies fish feed.

Each pen’s diameter is 50m. How large is that? An Olympic swimming pool is 25m x 50m. A fish pen would fit inside two Olympic swimming pools.

I was curious about how a fish pen compares to a land based farm by size. To do that, I looked up a center pivot irrigated farms in Kansas. The farms’ circular shape makes them stand out from the air.

I superimposed the image of a Norway fish farm on a circular land farm. The fish pens are just small circles inside the much larger circle. It has a diameter of 800m, the same width as the Golden Gate Park. If the entire Golden Gate Park is converted into circular farms, it can fit five of them.

Kansas is full of farms like this. Just see this when we zoom out to this 70 x 35km area. This is only one corner of Kansas.

I know little about the business of farming. But I bet that the yield, by economic value, is higher for the six salmon pens than the much larger grain farm.

What about calories? Could a fish farm yield enough to produce a meaningful share of protein for the world’s population? A 50m fish pen is large at human scale. But it is just a speck of dust relative to the vastness of the ocean. Could aquaculture scale up much more?

Perhaps we can innovate to produce food from much less land. Then we could stop cutting down forests for farms, even reverse the agriculture’s land use impact, allowing farm land to turn back into forests and wildlife habitat. The next green revolution could be world changing.

2021.09.22 comments