When and where squid come inshore

Squid fishing is overwhelmingly a night fishery, and the reason is not simply that squid feed after dark — it is that artificial light creates a hunting situation the animal exploits.

SQUID ARE VISUAL PREDATORS WITH EXCELLENT LOW-LIGHT VISION. Their eyes are large, acute and adapted to work at light levels where their prey's are struggling, which gives them an advantage after dark that they do not have at midday. That alone would make night the productive period.

ARTIFICIAL LIGHT THEN CONCENTRATES THE PREY. Harbour, pier, marina and street lighting attracts plankton, which attracts small fish, which is what squid eat. A lit quayside is a food chain assembled by accident, and it operates every night in the same place.

WHICH PUTS THE SQUID ON THE EDGE OF THE LIT WATER RATHER THAN IN IT. The consistent observation across this fishery is that squid hold in the dark just outside the pool of light and dart into it to take prey silhouetted against the bright water. Casting into the middle of the lit area is fishing where the prey is; casting to and along the shadow line is fishing where the predator is. That is the single most useful piece of practical knowledge in the discipline.

COMMERCIAL SQUID FISHERIES USE THE SAME PRINCIPLE AT SCALE, with vessels running powerful lights to draw squid up and hold them — a practice visible from space over some fishing grounds, and the same mechanism the shore angler is exploiting on a harbour wall.

MOON AND WATER CLARITY MODULATE IT. A bright moon reduces the contrast that makes an artificial light effective; coloured water reduces it further. Dark nights with clear water are consistently reported as better, which is a visibility argument rather than folklore.

TIDE MATTERS AS IT DOES FOR EVERYTHING INSHORE, because moving water concentrates prey around structure. Many marks fish through a particular part of the tide and are quiet otherwise.

AND DAWN AND DUSK ARE THE TRANSITIONS WORTH FISHING, when squid move up and in before full darkness and back out afterwards.

Anybody fishing inshore during the squid and cuttlefish season will eventually bring up eggs, and knowing what they are and what to do with them is part of the subject rather than an aside.

THEY ARE UNMISTAKABLE ONCE SEEN. Squid attach gelatinous finger-like strands, frequently in communal masses built up by many animals on the same structure; cuttlefish attach clusters of black grape-like eggs, stained with the animal's own ink, which is where the colour comes from. Both are laid on weed, rope, netting, pot lines, moorings and anchor chain, and both come up on gear routinely.

THE MASS IS THE PRODUCT OF MANY ANIMALS AND ALL OF THEM ARE DEAD. Because these species spawn once and die, an egg mass is the entire reproductive output of the animals that made it, and there are no adults left to replace it. Lifting one out of the water and leaving it on a quayside destroys a generation's worth of a local population's reproduction for no gain whatsoever.

SO THE CORRECT HANDLING IS SIMPLE: return it promptly and intact to the water, ideally attached to whatever it was on or to something similar, and keep it wet throughout. This costs nothing and it is the single most useful conservation action available to anybody in this fishery.

IT ALSO EXPLAINS WHY THE SEASON IS SELF-LIMITING IN A WAY OTHER FISHERIES ARE NOT. The record for European squid sets out that a stock rebuilt annually is entirely exposed to one season's conditions — and equally, that it can rebuild completely in one year, which no long-lived species can. Protecting the eggs is therefore unusually effective as well as unusually cheap.

MOORINGS AND POT LINES ARE THE COMMONEST PLACE TO ENCOUNTER THEM, which is worth knowing because it means egg masses are concentrated exactly where inshore fishing happens.

AND THE BROADER POINT TRANSFERS. Where the fishery targets an animal in the act of reproducing — as the record's spawning material describes for aggregating reef fish and for guarding freshwater predators — the restraint that matters most is exercised at the point of greatest opportunity. Whether any local rule addresses this is a matter for the competent authority, and most do not.