Surely that only means the price will rise to become an exotic delicacy, rather than "gone"?

Unless there is some kind of global control on catching, for example, blue-fin tuna (which travels outside of nationally controlled waters), "gone" seems more likely. The feedback loop of, the rarer the fish - the higher the price, will push some species to extinction in the wild.

I've never eaten sushi, so I'm not familiar with what fish are normally eaten, but can these fish be farm-raised?

Yes they can, they are farming a fish called Cobia in Queensland Australia that is a sashimi grade fish. The farming process is surprisingly good too, they worked with a local company and sorted out a crop based land grown food pellet for the fish to remove a large amount of reliance on pulling their food source from the ocean.

http://www.abc.net.au/news/2016-04-01/cobia-to-kick-start-mu...

Farm raising tuna is difficult. Not sure if it is done commercially yet and, even if successful, I would guess wild caught tuna will still be highly prized in Japan. It is really the Japanese market that is and will keep driving the high end of the fish market.

It's a little more complicated than just 'farmed vs wild-caught', as a lot of tuna is wild-caught, then transferred to floating pens to fatten up for up to a year. Penned tuna are neither truly wild, nor considered farmed as there is no breeding stock.

Sure. You'd have to be pretty lucky to find a wild salmon in a sushi place - and if you did it'd probably be twice the price.

A somewhat recent development in packing fish is automated cutting and vacuum packing - alive to wrapped in less than 30 (or so) seconds.

This is afaik also being done on factory ships, with fish like cod. Still rather new (a few years?) and expensive - but a great way to treat fish. Many of the advantages of flash freezing without the down sides.

We've eaten things to extinction before, so no, don't assume anything.

https://www.britannica.com/list/6-animals-we-ate-into-extinc...

I'm still hesitant to agree that we caused the mammoth extinction. There just weren't enough people at the time to do it with the technology we had, especially in places that lack enough cliffs.

We've had spears for quite a while now.

https://www.youtube.com/watch?v=mAvEmzjL_lA

That's a remarkable list, thank you for sharing it.

The problem is that then it becomes more lucrative to harvest.

For example, the high price of tusk and horn isn't saving the elephants and rhinos.

Perhaps, but not necessarily. There are real concerns that with a combination of temperature rises, ocean acidification, and trophic cascades caused by overfishing, the oceans will entirely die in the medium term. They are certainly in the process of dying (like nearly all ecosystems under the assault of 'economic growth').

Your assuming population response is linear, it isn't. Passenger pigeon showed us that populations can collapse rapidly below certain thresholds.

Increasing the incentive to catch every last one, presumably?

as long as it isn't subsidized like the livestock industry.

I'm european and I prefer salmon sushi and it probably won't go away anytime soon. salmon is easy to farm and produce in masses.

The problem with farming salmon is that the food pellets salmons eat are made out of wild caught fish. Typically, for every kg of salmon you need 2kg of wild caught fish...so not really sustainable.

Current food-to-fish ratios are much closer to unity, usually 1.1 to 1.2.

The nice thing about inefficiencies such as this one is that the cost is not externalized, thus companies have a large incentive towards reducing the problem.

what is that ratio of the wild caught salmon?

Literally a rush to eat fresh water eel while supplies last as we speak. (That is stoked by even supermarkets in Japan... ~_~)

what about farmed fish though?

I was under the impression that farm raised fish (compare to natural fish) has the same problems as farm/cage raised chicken/beef/etc...which is excessive use of antibiotics.

But that is a different problem with different, feasible solutions. Farm raised fish are our what we will be eating in the future.

Plant-based and lab-grown is what we'll be eating in the future. Farms (be it livestock or fish) are inefficient and cruel.

> compare to natural fish

You mean compared to wild fish. Farm raised fish are still natural.

But in any case, even if there was a lot of antibiotic usage, the point still stands: There will not be a shortage of fish.

Uhm, well, given that 1kg farmed salmon needs 2kg wild caught fish, there may still be a shortage of fish...

Tilapia eat vegetation, you can use them for feed.

Why does the salmon feed need to be wild? Why can't it also be farmed?

This ignores history. Every time some resource became scarce people figured out a way to get more, or find something else.

Once prices go up, people will figure out how to farm tuna, and then they will no longer be scarce.

A single tuna can lay 6 million eggs. You don't need that many to supply the entire worlds demand for it.

Every time, really? Like every single time?

https://en.wikipedia.org/wiki/Passenger_pigeon

This kind of short-sighted hubris is why we are on the cusp of ecological collapse.

Parent commenter should have said "every time something becomes scarce and highly-valued," although I'm sure there are exceptions to that as well.

Passenger pigeons weren't really a resource and wikipedia page says they were mostly driven to extinction by deforestation for land use and lumber and fuel... which are resources.

Weren't a resource? How so? Why were they hunted then?

Yeah you're right, without market forces we never would have built those blue whale farms.

/s

When blue whale blubber became scarce we .... switched to a new fuel. So that's actually confirmation of my point.

You're ignoring why it became scarce.