Fishing lines: Strike a blow for Britain - clonk a cat

Remember, you read it here first. The new must-have item for fishermen is going to be... a clonk. It doesn't look too special. In fact, it's just a bent piece of wood. But those who fish for the country's ugliest fish assure me that if you want to catch a catfish, get a clonk.

Remember, you read it here first. The new must-have item for fishermen is going to be... a clonk. It doesn't look too special. In fact, it's just a bent piece of wood. But those who fish for the country's ugliest fish assure me that if you want to catch a catfish, get a clonk.

A Budapest company exhibiting at this weekend's European fishing-tackle trade show, Efftex, in London have a stand offering only "traditional Hungarian hand-made clonks". A decade ago, they wouldn't have taken a forint. But in today's catfish- loving climate, they will probably do pretty well.

Imagine a slightly crooked hockey stick, with the business end replaced by the head of a large, rounded wooden nail. You might imagine that the idea was to brain your quarry. On the contrary: you whack the water repeatedly with the clonk, and it sings a song that cats find irresistible.

It sounds ridiculous. but serious catfish anglers say a clonk is almost as important as bait. Using echo sounders, they can watch a clonk draw catfish from 40ft of water or more, right up to the surface.

Nobody is quite sure why it works. Maybe it makes the noise of a love-hungry catfish of the opposite sex. Maybe it imitates a shoal of feeding fish. Some claim it mimics a frog on the surface. Whatever the reason, it has become a vital piece of catfishing equipment.

Catfish are still uncommon here. But it won't be long before they are living near you. A lake not 200 yards from me now holds catfish over 40lb. They shouldn't be there, but loonies unmindful of the effects of foreign species are smuggling them into England. And they're not kittens, either; one notorious Essex water contains a catfish of over 100lb with a distinctly foreign accent. That's like keeping an elephant in your window box.

Worse, the wels, or European catfish, is immensely greedy. It will mop up everything else in the water that's smaller than itself. Fine if you enjoy catching these prehistoric horrors, with their long feelers and little mean eyes. Bad if you want to catch almost anything else.

You might think the answer is for the Environment Agency to buy a clonk, flail away until Mr Catfish turns up, and net it out. If only it were that simple. Clonkers assure me that not just any clonk will do. Sky presenter Nigel Botherway, who actually collects clonks, tells me that you need a different one for different waters. So a Spanish clonk (called a buschello) won't charm the cats in Croatia, and vice versa.

So I'm not sure quite how much business Energofish are going to do, selling their Hunor Clonk. (They claim the River Tisza in Hungary is the birthplace of the clonk, though nobody really knows.) But I feel duty-bound to go along and find out more.

There is, of course, a sure-fire way to catch catfish. It is, however, so outlandish, so downright scary, that it will never catch on here. Or could it? Judge for yourself. I'll tell you all about it next week.