There is plenty of aquaculture in Britain but there could and ideally there would be a lot more. As the climate changes and floods and droughts become more regular and more severe, we need to control the flow of water over the land far better than we do; and that among other things means more ponds and other waterways; and they could and should be put to positive use, both for production and for conservation. We should also, surely, learn from and adopt at least some of the many different techniques from around the world and from our own history. We need, too, to extend the range of species of fish in particular but also of other creatures that we consider farmable. Fish farming in Britain tends to mean trout or off-shore salmon, both high on the food chain; but we surely need also to be raising species with more modest diets, notably carp and even tench.

Nothing of course is worth raising unless there is a market for it – and it would be to everyone’s advantage if we could learn from eastern Europe and particularly from the Jewish tradition, and from China, how to cook carp, of various species; or indeed rediscover the methods of mediaeval monks for whom carp ponds were de rigueur. Finally of course we need to integrate fish farming and aquaculture in general into mixed farming. This is brought to a fine art in South-East Asia including China where aquaculture is an offshoot of the rice paddies. Britain doesn’t grow rice but the overall ecology – fish, ducks, fertility – can surely be emulated. Finally, what applies to Britain must apply to other western countries too. We should be raising more fish (and other esculent aquatics).

The problems, though, are legion. Diseases spread easily in water. Ponds and lakes are highly susceptible to predators and to pollution – and fish farms in various forms have often polluted their surroundings. It’s becoming obvious, too, that fish are far more sentient than they have generally been given credit for, and welfare is definitely an issue. There is a great deal of excellent research and pioneer husbandry out there but there is a great deal still to be done.

For the present, this section is more of a statement of intent than a reality. We just don’t know enough experts. But this can be called work in progress at an early stage. Step one, after all, is to recognize that there is a gap to be filled.