Biomanipulation

Discuss general pike fishing topics here.
davebaker6049
Posts: 4
Joined: Fri Sep 08, 2017 9:51 pm

Re: Biomanipulation

Post by davebaker6049 » Wed Jan 22, 2020 7:10 pm

JohnLucas1316 wrote:
Sat Dec 28, 2019 8:16 am
I talked to a Natural England employee yesterday, and he explained a few things about biomanipulation.
It seems that a lot of wildlife benefits from clear water status, although the did not say exactly which wildlife. They had thought of piling in tons of Daphnia, but it would be too expensive. He assured me that the fish would be put back in after the water clears, and that improvements carried out to the river Bure mean that Hoveton Broad will stay clear. He assured me that wildlife that relies on the fish in Hoveton will find food in the immediate surrounding area.
So that's ok then.
He also explained that big charities such as the Wildlife Trust have to have enough money in the Bank to keep their businesses going for a while if all funding suddenly stops. So when the boss of the Wildlife Trust stated that they needed millions of pounds in the bank 'to fight anglers', she was probably only joking.

We also talked about the lack of roach in the River Wensum. Natural England say that silted spawning beds, the lack of bankside reeds to spawn against (apparently because the width of the river keeps altering) and signal crayfish are the reasons that roach have declined.
I did a search online and found a site by John Bailey, an angler who knows more than most about East Anglian rivers. He states that the Wensum is still perfect habitat for roach, and the problem is cormorants.
I don't know the Wensum, and have never fished it. Who is right, John or Natural England?
Frustratingly, there always seem to be differences between groups that want to scientifically verify everything, and anglers who can see with their own eyes what is going on. Natural England have probably calculated the numbers of crayfish per square metre of river bed, and counted the number of stalks of reed that roach would spawn against per fifty metres of riverbank, and come to their conclusion. John Bailey has seen flocks of cormorants eating roach. Who is right?

Finally, if the Wensum is full of crayfish, and pike eat crayfish, is the Wensum full of pike? Does anyone on here fish the Wensum for pike?
Has anyone tried using a crayfish pattern lure inched along the river bed?
Hi John
I live on the Wensum, in the middle to upper reaches. The areas that were famous for Roach fishing in the 70's. If fish the river for pike chub and roach. I was born and bought up in Taverham (those who know the area will know its on the Wensum and in easy reach of all the river). There are pike in the Wensum, but not in the numbers there used to be, whilst there are some big chub, gone are the days when you could easily catch a dozen from a single swim, and whilst I catch a few roach there is nothing to shout about. Signal crays are not a huge menace, some of the gravel pits are rammed with them, and yes I can take you to parts of the river where there are plenty in other spots there are none.

JB is correct, it is the cormorants that are causing the havoc, they are everywhere, I can show you roosts with 50 birds in them. It would be a surprising day if you did not see cormorants either flying past or feeding. Apart from pockets small fish have all but disappeared , and bigger fish are now found in ones or twos. It is not worth fishing for barbel anymore, and the big chub will go the same way once they die of old age or the otters find the last few. However the tidal Wensum in Norwich City Centre is full of fish, but how long that will last is a question, otters and seals are hammering it as we sit here.

The Wensum is a beautiful example of a chalk stream, but I fear that without some serious man made manipulation is will become a very average fishery.

JohnLucas1316
Posts: 128
Joined: Thu Jan 11, 2018 7:52 pm

Re: Biomanipulation

Post by JohnLucas1316 » Wed Jan 22, 2020 7:36 pm

Interesting how stretches of rivers in city centres often hold fish, but go out of town a bit and numbers drop off.
Is it people feeding bread to ducks; or people, traffic and lights on for 24 hours scaring birds?
Or possibly warmer water? Or all of the above.

davebaker6049
Posts: 4
Joined: Fri Sep 08, 2017 9:51 pm

Re: Biomanipulation

Post by davebaker6049 » Fri Jan 24, 2020 10:25 pm

I think its probably all of the above, I'm sure people keep the birds away. Though it seems animals are not scared as you can see otters hunting most days along the river in the centre of Norwich. We also have a resident seal at the moment.

I wonder if the reason there are more fish is because it is tidal, (why though I'm not sure) . All the rivers in Norfolk with tidal and non tidal stretches are the same, tidal is full of fish and non tidal is just small pockets of fish.

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