It’s hard for me to wrap my head around fish farming. I grew up commercial fishing the old-fashioned way, for one thing. Besides, it seems to me fish farming produces a much inferior product. But I try to keep an open mind.
It’s no secret that the fish inhabiting coastal waters are under a lot of pressure from warming sea temperatures and land runoff pollution. These two factors seem to have fish moving away from areas they normally inhabit and toward new areas where they haven’t been seen before.
A decade or so ago, I saw something on the PBS-National Geographic series called Strange Days on Planet Earth about what was then a new concept in fish farming — a mobile operation called an “Aquapod.” Since then, various versions of these mobile offshore floating enclosures that can be moved to areas of open water have been developed. The idea is to adjust the farms’ locations based on currents, temperature, and other conditions so that the fish are raised in healthier seawater conditions. The Aquapods’ design struck me as interesting: modeled on geodesic domes, they’re spherical mesh cages that drift with ocean currents, moored or tethered to a ship for relocation when necessary.
Then this spring, I read about Ocean Sovereign, a British firm that has worked with a Chilean fishing technology company, Ocean Ark Tech, to build the Ocean Ark. The concept vessel was shown off in a presentation in September at this year’s Shipbuilding, Machinery, and Marine Technology Trade Fair in Hamburg, Germany. It’s a big boat, 550 feet long and 197 feet wide, designed to operate offshore in waves up to 25 feet high. It’s made to mostly float, using engines only sparingly, for the purpose of repositioning. It’s able to travel four knots on its own power or can be towed by a tugboat.
The ship can be equipped with either eight 115-foot-wide cages or four 210-foot-wide cages strong enough to withstand harsh ocean elements and provide predator protection. It’s supposed to be capable of farming up to 3,900 metric tons of salmon, cobia, or even tuna, according to the online industry magazine Seafood Source.
You can imagine how it might work to move the fish away from marine heat waves, algal blooms, and storms, which are big problems faced by fish farmers. What’s most compelling is that this could mean healthier farming that would not increase pressures on wild fish stocks — in theory at least.
It was the middle of the 1800s when Charles Darwin was writing about how adaptation determines the continuing sustainability of a species. Now that we’ve had some time to digest that idea, maybe we need to consider adaptation in commercial fishing, because it’s clear the current model isn’t going to work in the long haul.
