As you read this on Wednesday morning, my Barbel Challenge will just have started.

What on earth, you're wondering? This is the deal. Back a few weeks, in the Angler's Mail, local fishing celeb Jim Tyree challenged me to catch a Wensum barbel. His contention is that they have been so thinned out by otters over the past few years, that actually landing one is only a faint possibility. I think Jim's Challenge was laid down because I always take the optimistic, perhaps rose-tinted view on things. My own belief is that the Wensum is a strong old girl, that she's protected enough of her barbel to make fishing for them a viable prospect.

I had to accept Jim's Challenge. How can I possibly admit that Wensum barbel fishing is absolutely done and dusted and consigned to the past? I think we all accept that barbel numbers are down and those that remain are abnormally spooky, even for a very twitchy species of fish. However, I'm trusting in my river and I'm trusting in my ability and it won't be very long now till we find out the answer.

The other side of the Challenge is the Charitable one. If I fail to catch a barbel, I pay £100 to the funds of the East Anglian Air Ambulance. If I succeed, then Jim pays £50. No, I can't explain the discrepancy either. I can only put it down to the fact that Jim is a Tyke, from Sheffield, and Yorkshire men are notoriously careful with their tenners.

Jim in his original Challenge gave me a week to accomplish the task. Throughout September I was just too horrendously busy to think of putting seven days aside in a back-to-back sequence. As of this morning, for the next seven days, I'm blissfully free. It's me, the Wensum and, hopefully, one or two of its barbel. The deal is that if I catch, I phone Jim on his mobile, day or night, and the whiskered little scamp comes out to photograph what will, hopefully, be a big whiskered scamp of a fish.

I'm obviously writing this before the event simply because of the needs of the press deadlines. The extended forecast looks as though it will continue comparatively warm, but perhaps with a few showers. This, if it comes to pass, will suit me perfectly. Obviously, this mellow autumn weather is exactly what I need to keep any barbel I might locate, feeding. If there's a tinge of colour to the water, that will only help my efforts. What I don't want is a plunge in temperatures and a deluge of cold, hard rain to fall.

I guess during the day my approach will alternate between a maggot attack, trying to build up a swim to a frenzy and, possibly, locating fish by stalking and then presenting something like a lobworm. Believe me, I hope either of these approaches works because I'm certainly not the night owl I used to be. The days when you'd find old JB haunting the river as dusk falls are long gone. You know, in truth, this is not because I've become a carpet slipper, pipes and Horlicks sort of bloke. No, it's rather that I now believe it's somehow fairer on the fish and a purer way of fishing itself if you can catch them during the daylight hours. The pleasure of the whole thing is enhanced, too. You see more of the world and its glories in the daylight hours and there's the colour and the dash of the fish as it fights. I totally accept that nocturnal triumphs are electric and pulsating and thrilling to the core, but no longer are they up there on my ladder of achievements. Mind you, if I have to fish into the night to pull this barbel out, then, believe me, Mr Tyree, I will.

On a simple level, win or lose, the East Anglian Air Ambulance will win out. I have to say thank you to one or two friends who have already committed their financial support to the Challenge, pitching in with a tenner each. If any readers feel equally inspired, that would be great. It's surely worth £10 of anyone's money to see old JB fall flat on his face.

On a purely piscatorial level, if I do fail in my Challenge, what does that say about river and my fishing ability both? Do I have to reassess my prowess as a barbel angler and/or do I have to rethink the health of my most beloved water course? I'm not a bad barbel angler, I guess. I've been catching them for 30 years and I think that if I'm faced with fish, then I stand a chance. The question is, will those barbel spots that I've known over the years still hold any fish at all?

Perhaps you'll see me up and down the river over the next seven days. If I'm plodding along a roadside bank, give me a toot. If I'm fishing on what you know is a barbel barren piece of water, come for a chat and let me know. Believe you me, I need all the support that there is out there.

Oh, by the way, win or lose the Challenge, the Air Ambulance will be getting my hundred quid whatever.