Zander

JayD

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Strange you don't understand why otters are thought to be the contributors to stock crashes (and especially Barbel) JayD as there is plenty of literature online and on here about it.

Search for eating preferences (Barbel as prey) and then consider the size of fish that the forms of predators eat.
Also look for Severn seal videos.

As for fish restocking,doesn't tend to happen much on the Severn and yet the Lower fish stocks are improving every year.

I do understand why that's thought to be the case Lee, but that isn't the question I asked.

I'll rephrase it,
If, as it's often said, there is an increase in furry, and feathery predators, and if as you said, there's also an increase in 'fishy' preds, then why is it that there are those who say that the prey fish numbers appear to be also increasing?

I can only think of a few reasons why that might be happening,

The prey fish numbers are being increased by stocking. You've ruled that out.

The water quality, conditions, and appropriate food supply is such that there is a fantastic survival rate of the prey fish. It must be an exceptional stretch of water if that's the case.

The predators are mainly preying on their own young and juveniles. Possible, but unlikely if the pred numbers are increasing, as suggested.
or
It could be a temporary situation that as I said in my earlier post, is not sustainable, and at least one of the elements is likely to 'crash' eventually.

I'm only asking as an interested angler, a layman with no qualifications, just my experience, observations and reading a few books over the years to go on. I wanted someone with more knowledge than me to explain how this scenario works in a natural environment. I'd assume that an increase or decrease in one of the things mentioned, would impact on one or more of the others.

John.
 

Lee Richards

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"You've ruled that out."
Did I ??? - I said that the Lower Severn is not stocked.

"The water quality, conditions, and appropriate food supply is such that there is a fantastic survival rate of the prey fish. It must be an exceptional stretch of water if that's the case."
Not at all - you will find that many rivers are in healthy positions with certain fish stocks but the angling traffic has significantly dropped and anglers are unaware of this.

"The predators are mainly preying on their own young and juveniles. Possible, but unlikely if the pred numbers are increasing, as suggested.
or
It could be a temporary situation that as I said in my earlier post, is not sustainable, and at least one of the elements is likely to 'crash' eventually.!"
Fact or your presumption-please explain where you are getting this from?
I personally do not fish one water where there is a prey/predator stock imbalance.

In reference to your post relating to large predators I made a point that you should look at Barbel stock crashes and the correlation to otters.
Would still be interested for you to do this as I don't think you understand the eating preferences of our freshwater Predators and the main non-aquatic predators that have an impact on the fish stocks.
 

JayD

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"You've ruled that out."
Did I ??? - I said that the Lower Severn is not stocked.

"The water quality, conditions, and appropriate food supply is such that there is a fantastic survival rate of the prey fish. It must be an exceptional stretch of water if that's the case."
Not at all - you will find that many rivers are in healthy positions with certain fish stocks but the angling traffic has significantly dropped and anglers are unaware of this.

"The predators are mainly preying on their own young and juveniles. Possible, but unlikely if the pred numbers are increasing, as suggested.
or
It could be a temporary situation that as I said in my earlier post, is not sustainable, and at least one of the elements is likely to 'crash' eventually.!"
Fact or your presumption-please explain where you are getting this from?
I personally do not fish one water where there is a prey/predator stock imbalance.

In reference to your post relating to large predators I made a point that you should look at Barbel stock crashes and the correlation to otters.
Would still be interested for you to do this as I don't think you understand the eating preferences of our freshwater Predators and the main non-aquatic predators that have an impact on the fish stocks.


I don't recall singling out large preds, or making reference to their eating preferences, Lee, just the predation levels in general, and questioned how an increase in overall predation, could lead to an increase in prey fish levels? A situation that I personally haven't encountered/noticed lasting long term. I put forward a few theories I had, (not presented as facts), and invited others to offer theirs.
Maybe it's me, (could be 'an age thing' ;)), but I took your answer of,
"As for fish restocking,doesn't tend to happen much on the Severn and yet the Lower fish stocks are improving every year.", to mean the stocking on the Severn in general, and not just the lower sections, that's why I ruled out my theory.

I've read your many posts on otter predation, and the effects on the barbel population in your area, and realise that you are passionate about the subject, and hold strong views on it, but I wasn't questioning that at all.

I didn't put forward anything as fact, just a few theories that came to mind based on my past experience.
Over the years I have known waters that have had a prey, pred imbalance, usually due to either a very good prey fish survival year, followed by an increase in the pred numbers over the following years, or a reduction in prey numbers, causing an eventual fall in pred numbers due to the reduction in the numbers of food fish. The two natural examples that stand out in my area, are the disappearance of the roach following the disease in the 60s leading to an eventual fall in pred numbers after an initial fall in other prey species stocks, that had filled the gap in the food chain created by the reduction of the main prey fish, ie roach. The other was the hot dry summers of the mid 70s, resulting in a fantastic fry survival rate, that eventually resulted in a boom in all pred numbers. Neither of these situations lasted, and nature eventually created a 'new' balance, with different species being at the fore. I have also known several other more localised situations on individual 'natural' waters, where the imbalance has been caused usually by the introduction of a species alien to the water, again a kind of balance was eventually created, but different to the initial one.

I apologise for the 'long winded' reply, but I felt that we were discussing two different aspects of the same situation. Yours a specific one, mine a more general one, and I wanted to clarify my own posts, I hope I have now done that.

John.
 

160642fishing

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I’ve heard that our Eastern European friends have decimated the pike and Zander on the Fens now. Is it that true do you think ?
Mick the Eastern Europeans have decimated the Pike stocks in the Fens mainly through night lines,their angling ability in the main is poor and I see them regularly on the Forty Foot lure fishing,I have never heard of a Zander being caught on a lure (I'm sure someone will correct me on that ) and as I've said previously on the thread they are very shy biters,the pack fish usually seemed to run in the 2 to 4 pound class and they would attack shoals of very small roach after wounding and killing them they would then drop to the river bed to pick them up,thats why we would use very small roach or bleak tail hooked with a single hook legered to catch them,they do have a much smaller mouth than a pike.
 

Pompous git

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Zander munch their way through roach stocks, it`s what they do for crying out loud. Perhaps some of you think they live on fresh air.

I have never heard such a load of selfish cobblers by people with closed minds regarding zander.
 

Yuccaman

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Zander munch their way through roach stocks, it`s what they do for crying out loud. Perhaps some of you think they live on fresh air.

I have never heard such a load of selfish cobblers by people with closed minds regarding zander.
Hmmmm.... yes. The Riverfest Final results at Stoke Bardolph definitely back that up. Are you sure the closed minds only work in one direction?
 

tipitinmick

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Zander munch their way through roach stocks, it`s what they do for crying out loud. Perhaps some of you think they live on fresh air.

I have never heard such a load of selfish cobblers by people with closed minds regarding zander.
Have you got a few Zander around where you are PG ? Nearest I think we have is on the Trent I reckon. 🤔
 

tipitinmick

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Mick the Eastern Europeans have decimated the Pike stocks in the Fens mainly through night lines,their angling ability in the main is poor and I see them regularly on the Forty Foot lure fishing,I have never heard of a Zander being caught on a lure (I'm sure someone will correct me on that ) and as I've said previously on the thread they are very shy biters,the pack fish usually seemed to run in the 2 to 4 pound class and they would attack shoals of very small roach after wounding and killing them they would then drop to the river bed to pick them up,thats why we would use very small roach or bleak tail hooked with a single hook legered to catch them,they do have a much smaller mouth than a pike.
Breaks my heart reading posts like this. My dad used to take me to the forty foot when I was young. In fact I think we once fished a pike championship qualifier on there when I was about 15 years old. Oh dear. What a shame. 😩😩😩
 

Pompous git

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Hmmmm.... yes. The Riverfest Final results at Stoke Bardolph definitely back that up. Are you sure the closed minds only work in one direction?
The Stour near me has had no end of pollutions over the years. The worst was when several hundred gallons of concentrated lemon
juice leaked into the river from a perfume factory and wiped the waterway out for several miles, from Willsborough Lees to the weir
pool at Wye to be precise.

Each time it takes ages for the river to recover but it seems it is forever being knocked back.

The upper Bure is another case, the roach hammered. A three pounder was caught a few years back and this was held up as an
example of how good the river was, a seven pound chub too, again used as an example. These fish were survivors not a sign of
how hunky dory everything is.

I don`t know where Stoke Bardolph is but if the river is good then fine by me but I could go on and on regarding waters that have
and continue to suffer. In the general scheme of things zander would be another disaster but here you and others are arguing how
wonderful they are.

The introduction of zander means death to thousands of roach and I repeat, the only good zander is a f*****g dead one.
 

Yuccaman

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I don't disagree that they shouldn't be introduced to waters which don't have them, but you can catch double figure zeds AND huge nets of silvers out of the Trent from anywhere along 40 or 50 miles of it, and that's simply a statement of fact, rather than opinion. There are questions over the disappearance of gudgeon, and that's actually generally now a bigger question than the roach. Where you have an established population like that, one person removing the odd fish won't dent it.

As I said in my earlier post, once the water balances out, (and this is only instinct) I imagine that the most likely 'victims' are actually pike.
 

Pompous git

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I don't disagree that they shouldn't be introduced to waters which don't have them, but you can catch double figure zeds AND huge nets of silvers out of the Trent from anywhere along 40 or 50 miles of it, and that's simply a statement of fact, rather than opinion. There are questions over the disappearance of gudgeon, and that's actually generally now a bigger question than the roach. Where you have an established population like that, one person removing the odd fish won't dent it.

As I said in my earlier post, once the water balances out, (and this is only instinct) I imagine that the most likely 'victims' are actually pike.
I hope the next zander you catch bites your knob.
 
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