Back in January I suggested a number of possible blog posts. Though it is disappointing that nobody commented publicly I have had a few encouraging conversations, so here goes on one of those...
Human Beings have fished for food for a very long time. It is certainly measured in multiple millenia, and some have suggested that it has been so long that we have evolutionary traits to enable us to do it better. The seas and oceans are also vast, which in the past (with a world population in the millions) meant that the human impact of fishing was negligable. In the last few centuries, with industrialisation, improved medical knowledge, and advances in the political and social world, we have rapidly increased the population by nearly a thousandfold. The sea, however, has much the same capacity as it always was, and so we now have a very significant impact indeed on it.
There are many cultures and peoples who, over the centuries, have built up ways of life, dishes and traditions around the sea; from living on it (Bangladesh, Venice) to living by it (North Sea, Spanish and other villages). Traditional foods such as those favoured in Japan (Tuna, Sushi) and China have also become ingrained into societies that are now far bigger than the food chain can support.
We are constantly being told about areas where fish have essentially run out, of the demands of fishing quotas and of barren seas. Many people know that the coral reefs are suffering from a variety of causes, but those who dive know of the devastation that fishing trawlers have inflicted on the sea floor. Marine Divers know of the depressing state of that sea floor - of an essentially barren seascape with almost no life - animal or plant. The few areas that have been protected, for example the marine nature reserves of Strangford Lough, and off Lundy, remind us of how it should be elsewhere. The UK is slowly starting to act - the instigation of the Marine and Coastal Areas Act 2009 and the resulting proposal for Marine Conservation Zones is a help; however, there is still no agreement on where these zone are, how big they are or how many there might be, and of course it's all UK-centric; move outside UK waters and things return to anything goes.
We should have accepted by now that we cannot continue to pull fish out the ocean without limit. The seemingly instatiable demand that the World's population has for fish has grown beyond the capacity of natural ecosystems to replenish -- and yet we seem to be more interested in saving fishermen's jobs tomorrow than ensuring that there are any fish in the sea next season.
We need action... and I believe the only effective action we can take is to ban the fishing of the oceans on a large scale (individual line fishermen, probably, can continue). I say ban, not limit or quota, because limits don't really work: you can't "uncatch" fish effectively as throwing them back is usually a death penalty anyway, whether because of the damage the fish suffers in being caught, or from the predators that follow fishing vessels. Even if it were effective, there is always the issue: how many is enough? Lobbyists will always push for a bit more, and politicians are usually swayed by the here-and-now. Finally, what about quotas: well, as we have seen already, deciding that you should not catch cod (because there really are very few left, relatively speaking) and hunt tilapia, or haddock, or ... instead just means extra pressure on those other species. And they can't cope any more than the cod could. A quota just doesn't work in the long term when the pressure is this great.
We can continue to farm fish: at least, we can if we don't kill wild fish to feed the farmed ones, as has been happening with some sorts of farmed salmon. The Ecologist reported that up to 4Kg of wild caught fish is used to feed every 1Kg of farmed Salmon... hardly the ideal "let's not add to the burden on the sea" scenario. If we are to farm fish we need to find ways of farming in isolation from the sea; whether that is through farming algae-eating species, or some other way, I don't know. But relying on the sea is no longer an option.
Maybe, just maybe, we can come back in 50 or 100 years and start relying on the seas for food again. In the meantime, along with all the other pressures for food production, we must refrain, or lose the very thing we want.