One species’ demise is another species’ opportunity. It would seem that there has been an explosion in the lobster population around our coasts in recent years, particularly in Scotland and those parts of England flavoured by the North Sea. The cod have vanished, possibly forever, possibly just elsewhere, no one really knows. Our cod used to feed off baby lobster as if they were canapés.

There is something fabulous about the live, uncooked lobster, about its glistening deep blue colour speckled with white, about its formidable jointed armour, its massive claws and beetling antennae. It looks elemental and indestructible. But cooked, it takes on an almost feminine orangey-red as heat denatures the proteins that give them their protective colouring, revealing, apparently, their true colour given them by their diet.

We tend to eat more of them in summer because they’re easier to catch. Sluggish in winter, they liven up as the water warms, and move to shallower waters. Being bottom scavengers, they’re not hard to catch, but if you go diving for them, or lobster-potting on your account a) be careful of professional lobster fishermen, who tend to guard their fishing grounds pretty fiercely; and b) don’t take any lobo smaller that 87mm from tip to toe of the carapace; and c) if you catch a lady lobster with eggs stuck to her underside, let her go to make sure that there’ll be future lobster for future generations of lobster-eaters. In my view, a lobster about 400-600g is best. Larger than that, and they’re beginning to turn into muscly old brutes.

When it comes to killing them, just follow the instructions shown in the video on this fabulous website (I hope there is one), which follows generally accepted principles. If you drop the lobster into boiling water, it’s a) not very kind; and b) tends to toughen up the lobster flesh unless you’re very careful. Once cooked, do with them as you will.

NB. There are also Flat Lobsters, which you find in the Med; and Spiny Lobsters (or Crayfish) which you find in the Med, and which occasionally turn up around our southern coasts. These are easily distinguished; they have no claws. Of course, in this country, Crayfish usually signifies the freshwater crustacean, but I expect you know that.

As a small boy I used to spend hours attempting to catch wily prawns in rock pools near Brighton. There was something magnificent about their glowing pinky/red when freshly cooked, the imposing curve of the saw edged horn projecting from their heads, their dainty feet and the sweet delicacy of their flavour. Whenever possible buy uncooked prawns. They invariably taste better, and their smell gives you a better idea how fresh they really are.

Very, very occasionally you see Selsey prawns, which are the closest thing to the delicacies of my childhood, and should be snapped up immediately. More frequently you see the rather more generic Atlantic prawns. These will almost always have been cooked, but are worth buying in the shell, even if it’s a fag having to peel them yourself. The shells boiled up with white wine, onion etc., make a really punchy and easy base for a sauce. Don’t bother with the ready peeled variety. They have all the texture of small curls of cotton wool, and much the same flavour too.

You do come across very large, deep water Atlantic prawns more frequently. Having said all that about our native prawns, most recipes specify the warm water tiger prawn, the product of commercial farming. These are the subjects of a good deal of angst among environmentalists, and, in truth, don’t really taste of much, although they have a good, firm, meaty texture. Most supermarkets sell organic versions, and buy them if you must. Raw, of course.

Around our shores there are Great Scallops (big) and Queen Scallops (very small). There are dredged scallops (not good) and hand-dived scallops (good). Dredging destroys the seabed habitat and can result in scallops being muddy or gritty.

Hand-dived means they’ve been selected individually by licensed divers, which in theory should produce a better class of scallop. They also tend to more expensive. You pays your money and you takes your choice. Either way, always buy your scallops in the shell, unless you have a close and trusting relationship with whoever sells you your fish. And beware, above all, of scallops sitting in liquid. The big white adductor muscle, the main eating bit, acts as a sponge just soaking up the water in which they sit. When you come to cook them, they will shrink alarmingly, exuding a lot of milky fluid as they do so.

The fresher the scallop, the sweeter and naturally firmer it will be. Most scallops have hermaphroditic tendencies, so when you eat them, you’re also eating both sets of sexual organs. The female organs are bright orange, the male a pale, white-ish colour. Perhaps that’s why scallop shells were once seen as symbols of fertility.