I'm in Brussels, at the annual European Seafood Exposition. In the shadow of the improbably-shaped Atomium, thousands of people gather to buy and sell seafood. Five vast halls in an impossibly imposing building, crammed for three days with every sort of seafood you can imagine, as well as quite a few you hadn't yet dreamt up. The scale of it takes your breath away. This is the world's largest seafood fair, and quite literally it's the place the big-money deals are done to trade away our ocean life.