I realise that a lot of fishing is done on artificially-stocked lakes, both in the trout and the commercial angling worlds. In both cases, important needs are being met, especially, as on many of our stills and rivers, wild fish are in comparatively short supply.

It's probable that if natural lakes and rivers were still teeming with fish, anglers would pursue what nature provides, rather than the lorry from the fish farm.

It is good to read Roy Webster's roundup each week as he often features those matches fished on rivers and where big weights are often recorded. Roy highlights the fact that modern match anglers still relish the challenge of natural waters and can still prefer a 40lb bag of hard-won bream to a 200lb bag of overly-easy, identically-sized carp. This taste for the wild is, then, still a part of fishing, despite our environmental troubles, and gives me the heart to continue not only this piece but the work I do to help restore our natural fisheries.

Can I also reaffirm at the head of this column that I think the Environment Agency fishery team in this region are doing a fabulous job to a degree none of us would have dreamed possible 30 years ago. The people at the Agency have problems with finance, but not with either will or vision. Helen Beardsley, Rob Dryden, Steve Lane and their colleagues are working wonders and those would become miracles if austerity didn't weigh them down.

Still, the fact remains that despite all this positive, well-meaning input, stocks of fish in our rivers, especially, are not improving. The baseline of the graduate, professional fisheries expert is that this is largely down to habitat. I'm neither a fool nor a Luddite, but I am out on our rivers every day of my life and whilst I relish habitat improvements these are proving not to be the finite solution to our rivers' problems. If we examine the upper Wensum, Bure or Yare, to my eyes habitat is far better than back in the '70s when I first observed it. Yet, fish stocks are a fraction of what they were when those water courses were little more than dredged-out drainage ditches running to the sea. There is evidently something else going on here.

At a Wensum Working Group meeting last week, Rob Dryden gave an excellent summary of the EA's attempts to rejuvenate barbel stocks in the Wensum. I have to précis, but between 2009 and 2013, 4,520 juvenile barbel were stocked at various sites, all electronically pit-tagged so their movements could be recorded. In essence, over the two or three years following each introduction, recordings of the barbel dwindled dramatically before dying out altogether. As Rob concluded, stocked barbel disappear totally after three years and leave no evidence that stocking works. I think it is fair to say that Rob has hunted for all sorts of good scientific reasons for this, but the fact remains the only one that makes real sense is predation. By that, I mean largely predation by cormorants.

We fanatical river anglers do serve a purpose, if only because we are on the river day in, day out and vitally, often before the Environment Agency is up and at work. Dennis Willis is an angler and environmentalist I have huge respect for and he was at the same WWG meeting in question. A couple of days later he circulated an email saying, amongst other things: 'I attended three of the four sites where two-year-old barbel were released into the Wensum some three years ago. I met an angler who advised me he had counted 14 cormorants working the river at Taverham Mill the day after the fish were introduced.'

I know this does not qualify as pure science, but I believe every word because I see similar scenarios, time and time again, month after month, season after season. Let's look back to 1977, when old-timers like me, John Wilson, Tom Boulton and many more were catching river fish for fun. Forty years on, the rivers are in better shape and, as Helen Beardsley commented, water quality is far improved, too. Fish stocks, though, have plummeted. We can look at the whole A-Z of possibilities, from agricultural pollution to zander introductions, but the only really viable reason is that since '77, cormorant populations have risen many fold to unsustainable numbers. In the eyes of many experienced, sensible anglers like Dennis, it is an unpalatable probability that until cormorants are controlled, our natural, wild fish stocks will crash to complete annihilation.

Finally, I speak also as a birder and a member of the RSPB. When in the recent past, cormorants have decimated fish stocks in many of the lakes I have known since childhood, fish-eating birds like grebes, herons and kingfishers are necessarily eradicated as a result.

Speaking as a birder and a fisher, until we really face the cormorant threat and act on it, the only fish we will catch will have been driven up the A47 and the only aquatic birds we will see are big, black and have recently arrived from the continent.