Many anglers claim that the carp is the most intelligent of all freshwater fish and others with equal conviction that it is among the most stupid. Both I suspect, are correct. In countries where carp are way down on the order of anglers priority for example America and Canada, they are easy to catch, in the rivers and lakes In Spain they are suicidally easy.

Why should they be considered so clever in other places, like most of Britain.
Perhaps it is because in Britain carp and the pike are the biggest fish by far and attract considerable attention.
While the Americans and Swedes are obsessed with predators, and have several hard fighting game fish to concentrate upon, much of Britain has carp and pike at the top of the list.

It is in Britain that the carp has received the most specialised attention over the last thirty years, prior to that carp were considered virtually uncatchable  because the fishing tackle available could rarely land them, even if they were hooked.
Only a handful of carp enthusiasts were making progress, until 1952 when Richard Walker designed the split cane rod with the power to land large carp.
In that year he almost doubled the British record with a fish of 44lbs from a tiny lake in Herefordshire. Suddenly big carp were catchable, and Walkers feat set in motion a bandwagon for carp which is still rolling today.
More and more waters are stocked with carp and today it seems rare for a week to go by without the capture of carp over 40lbs.

One fact to emerge from this is that the more people fished for carp the harder they became to catch. Although I am by no means a carp specialist, I once fished a water back in England that was rarely fished and held carp.
The first time I caught 100lbs of carp up to 5lb, on a simple float method with sweetcorn. The second time a lot less, and after a few visits it became difficult to get a bite on that bait.

It seems crazy to suggest that every carp in that lake had either learned from direct experience that sweetcorn meant trouble, or that those which had not been hooked had been frightened off by the wary reactions of those which had been caught before. But I believe it to be true, and doubt if I could find a carp specialist in Britain or Sweden who does not believe it too.

The whole history of the sport backs it up. One of the earliest methods was simple floating bread crust, which carp would engulf with relish.
Once caught, however they would start nudging large crusts with their noses, eating only the small pieces which broke off.
Anglers began fishing a small piece of crust attached to a larger piece, with the hook in the smaller section. That worked for a while until the carp also got wise to that trick.

Since then it has become a recognised fact that carp, and especially large carp, do have the capacity to remember that they have been caught on a particular bait and that they can retain the memory for a considerable time.

The other big difficulty is that carp become extremely wary of anglers terminal tackle. For example when sucking in a bait they could detect and take alarm at the stiffness of a strong nylon monofilament line, and promptly eject the bait.
People thought that the carp would not take the bait because they had seen the thick line, but Mr Walker again proved this wrong. He could get positive bites using braided lines much thicker than nylon and even easier to see. The difference was the suppleness of braided line, it allowed carp to suck in the bait without feeling anything to cause alarm.

These are just a few examples, small pieces of a giant jigsaw puzzle which forms the development of carp fishing.

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