Millions would struggle to eat and earn enough

Around the world, 40 million people earn their living directly from catching wild fish, while another 19 million are employed in aquaculture – fish-farming or growing seafood in controlled conditions such as sea pens and cages, lochs and ponds. But these figures may hide the true extent of the planet’s dependency on fishing. Along coasts, estuaries and coral reefs, millions of small-time fishers make a meagre wage from fishing, or catch fish just to put food in their families’ mouths. Some fishers don’t make the stats, and neither do their catches. “A lot of the small-scale catches are distributed in informal markets, where they’re not recorded,” says marine ecologist Dr Steven Purcell at Southern Cross University in Coffs Harbour, Australia. His own studies suggest that 71 per cent of those fishing for Trochus sea snails in the Samoan islands eat them themselves or give them away to friends and neighbours. Seafood is a major source of protein across Southeast Asia and islands in the Indian and Pacific Oceans. So while in Europe or the US we could eat more meat or soy products to make up for lost protein, a fishing ban could lead to food scarcity in communities with little land-based farming.

We can also envisage a black market developing for fish, as there currently is for beluga caviar in the US, where it’s banned. Eggs from the endangered beluga sturgeon are thought to be flown in privately to top Manhattan chefs. In the case of a total fishing ban, think less about caviar, more about ordering canned tuna from dodgy websites.