Depth of the Sea: Fishing in the Deep Sea

The European Academies Science Advisory Council warned of the “dire consequences” for marine ecosystems and against the “misleading narrative” that deep-sea mining is necessary for metals required to meet the transition to a low-carbon economy.

The deep ocean is generally defined as the depth at which light begins to dwindle, typically around 200 meters (656 feet).

Picture a parched desert, where for kilometers around there is mostly nothing growing, every few hundred meters an edible vegetable plant blooms, fragile and rare. While beside the desert is a natural garden where vegetables, and fruits grow in abundance.

I believe most of us would feel a bit guilty, sad or bad knowing we were eating a salad made from an ecological rare desert vegetable when the option is there to eat juicy tomatoes and arugula without devastating the garden from which it was grown.

I like using land based analogies for making a point about oceans. Humans are land based creatures after all, so it is a relatable way to get a message across. The deep ocean is like a desert, it is not that productive, normal processes of growth of sea life is very slow. The sea life at great depth lives naturally a very long time, some live up to 150 years or more. Annual growth rates for deep ocean biomass is usually less than 1 per cent. Fish live in complete darkness with no sunlight to help accelerate growth.

“The deep sea is the world’s worst place to catch fish” says marine ecologist Dr. Elliott Norse, founder of the Marine Conservation Institute in Bellevue, Washington USA. “Deep-sea fishes are especially vulnerable because they can’t repopulate quickly after being overfished.

This summer the deep sea has received more notoriety than usual because of the demise of the OceanGate submersible Titan. By now the cause for implosion of the ill-fated sub has been well combed over with the verdict being a nonchalance for safety by its creator and captain combined the jerrybuilt of its structure and controls. Basically it was a combination of mindset and material that directly led to the sub’s and crew’s tragic end.

When considering any activity at great ocean depth you need your head screwed on straight and serious investment in infrastructure to reduce risks. But the sparseness of deep sea fisheries make such investments costly given the return on such investments. This fact offers perfect segue into another land based analogy – mining.

“With slow-growing fish, there’s economic incentive to kill them all and reinvest the money elsewhere to get a higher return-on-investment. Killing off life in the deep sea one place after another isn’t good for our oceans or economies. Boom-and-bust fisheries are more like mining than fishing,” Dr. Norse said.

Last month July 2023 deep sea fishing and mining interests collided. Ireland and Sweden joined ten other countries calling for moratorium on extraction of metals from seabeds as a UN-backed authority prepared for crucial talks.

I find this debate interesting personally because prior to entering the seafood business I worked in mineral exploration for the world’s largest gold mining Placer Dome company with mining operations in ecologically sensitive areas all over the world. This mining company which at the time seemed as permanent as granite dissipated in 2006.

Last month, the European Academies Science Advisory Council warned of the “dire consequences” for marine ecosystems and against the “misleading narrative” that deep-sea mining is necessary for metals required to meet the transition to a low-carbon economy.

Environmental considerations aside, mining is an expensive endeavor especially if you are doing it deep underwater. The economic incentive for competitive extraction is questionable. To be competitive at today’s gold prices which are approaching an all time high you would need to keep your cost of extraction to below $890 an ounce.

I doubt you can do that safely at ocean depth. If we use the cost to be a passenger on the Ocean Gate sub as a yardstick for a pricing model that indicates its true costs, $250,000 per person for what was to be an 8 hour tour. In this case even more investment would have been needed for success.

I can’t see any resource activity at deep ocean justified either environmentally or economically. As for tourism I need to do more research. But personally I think visiting the Titanic for entertainment a bit crass. It’s a graveyard and some reverence is needed there, as for the creatures of the ocean deep.

Though some of the fish we sell come from the ocean deep such as black cod (150 to 300 meter). We are sourcing within a managed quota based fishery operating for decades.

Albacore (300 to 400-meter depth) is arguably a deep water fish. However, these are not ecological sensitive zones and the stocks replenish with a life span of 12 years. In contrast Orange Roughy, a popular seafood our company avoids, lives for over 200 years (1500-meter depth) and was thankfully delisted by Canada’s largest retail chain Loblaw’s. I would feel terrible eating any fish or animal that has a centuries long life span.

Smokey Bay Seafood avoids selling fish harvested from fragile environments. All the seafood we sell can be traced to its source. The seafood we sell is from regional, coastal, small scale fisheries on both Pacific and Atlantic Coasts: Dungeness crab, Pacific oysters, manila clams, wild sea scallop, sea urchin and whelk for instance. All this seafood comes from ocean depths and regions abundant as the garden I mentioned in the introduction to this blog post.