Rivers and Barbel decline?

[dicky123]

Be reading a lot lately about the demise of many barbel rivers. I don't know why or if it's true, but if it is what is the cause do you think?

Rivers too clean? Predation, otters and mink, cormorants? Whats your opinion?

Only fishing two rivers does not give me a good perspective to be honest.

 

[108831]

It is true,add water abstraction and weather patterns changing(for whatever reason),this just adds to the effect of any or all of your other suggestions,there are very few rivers in the UK with natural indigenous populations of barbel,certainly none on the west side of the country I believe and as our human population grows,it seems our barbel numbers drop.

 

[thecrow]

Lots of things imo that have combined to make some rivers an unsuitable habitat for Barbel.

Imo anglers can partly blame themselves in so much that by using high oil pellets fish have died from the effects, I have no proof of this its just my opinion. They are not good for the fish, a bit like someone living on chips and burgers alone.

Predation despite what some would say has affected some rivers where the fish were already on the edge, imo (its all opinions) they are mostly the smaller rivers that have been affected but not all, those that have had populations of predators for as long as can be remembered do not seem to have been affected as badly if at all, its my belief that its this that causes so much difference of opinion when it comes to predators.

The very fact that the EA have stocked many thousands of Barbel into rivers over many years imo shows that one of two thing is happening, the first is that the rivers they are being stocked into are unsuitable for maintaining a natural stock of Barbel the second is that our rivers are not as clean as the EA would have us and the public believe that our rivers are the cleanest they have ever been and while they might look cleaner they are not, they are full of invisible pollutants.

All of this of course might be total rubbish and the Barbel populations of some rivers and even some stretches of river could just be at the bottom of a natural cycle caused by who knows, rivers and fish populations are ever changing anglers need to recognise this and change with them.

 

[108831]

The trouble is anglers fishing rivers like the Trent Severn and Wye, think everything else is a small river,barbel rivers of long standing such as the H.Avon and D.Stour are small,the Gt.Ouse around Radwell,Sharnbrook,Pavenham and Harrold are of similar size,Adams Mill however is a small river,all of the Ouse however is struggling,the Avon and Stour have lower populations than i've ever known in my lifetime,why the hell there isn't more definitive evidence available I do not know,unless they know but don't want to divulge their findings for whatever reasons.My own opinion is that eventually the larger rivers will decline too,I hope not,but just feel it is a matter of time,the northern rivers of Yorkshire and I believe Lancashire will last longer because climate changes are not so obvious...yet...

The powers at be don't give us definite reasons,then threads like this one will keep us guessing.

 

[steve2]

Could it just be that these river aren't natural barbel rivers therefore barbel can't reproduce. Most of these river have been stocked with barbel either legally or not so maybe they have reached the end of their life cycle. So without further restocking barbel will die out and the natural balance will return.

 

[thecrow]

Could it just be that these river aren't natural barbel rivers therefore barbel can't reproduce.

The biggest thing stopping Barbel and other species reproducing is the amount of endocrines that have been flushed down the toilet when women are on the pill, it could be filtered out but the water companies would need to spend an awful lot of money to do it and I don't believe they have the will to do it.

 

[theartist]

Lots of theories going on here but some of the most prolific waters are directly below sewage works and see a lot of pellets surely ruling out those as possibilities.

The Kennet, Great Ouse, Teme and Ivel are most notable for a decline in Barbel numbers, now what do those rivers have in common?

 

[thecrow]

This is the latest I can find on this, its from the states but I think it would also apply to our own fish, indeed considering the higher population for a given area in this country the effects could be worse.

https://toxics.usgs.gov/highlights/fish_endocrine_disruption.html

Lots of interesting links within the article.

 

[108831]

Could it just be that these river aren't natural barbel rivers therefore barbel can't reproduce. Most of these river have been stocked with barbel either legally or not so maybe they have reached the end of their life cycle. So without further restocking barbel will die out and the natural balance will return.

Steve,your theory of barbel being stocked doesn't really hold,I was at the stocking of the Ouse at Radwell,Sharnbrook and Milton Earnest,those fish did the barbel norm after stocking,disappear for ten years,when they started to show there were fish of mixed sizes,from 6ozs to 8-9lbs,ever since until 7 or 8 years ago small barbel could be seen on the shallows above Radwell bridge,but survival rate seems poor,a similar story can be said for the Ivel up until 2 years ago,also populations on both rivers was stable,until a sudden downturn,on the Ouse first,then the Ivel and please don't forget Severn and Wye fish are not naturally there,they were stocked from the Thames in the Severn's case,now the Thames's barbel only survive by stocking by the EA.

P.S. On the Kennet it was very prolific,these fish were not stocked to that level,many huge multiple catches were taken,actually similar to the Severn,one plus is the large numbers on the upper Lea,a tiny river,little more than a stream...

 

[dicky123]

Has anyone brought up the pellet thing before? I've been told about it in carp lakes, but carp aren't barbel, they seem to stand much more pollution and suffer less decline.

Maybe rivers like the Trent will become huge carp venues in the future.

I spoke to one chap that only fishes for carp on the Trent, and has been doing so now for several years he told me.

It's a very sad situation.

 

[steve2]

We always go on about predators damaging fisheries don’t forget Barbel also eat plenty of fry and spawn. So may be the barbel are eating themselves out of existence. It could also be that the plague of carp infesting many waterways maybe having an affect on Barbel because like Barbel they will also eat plenty of fry and spawn.

As a matter of interest was any detailed research carried out before Barbel were stocked to find out the affects on other river species.

 

[thecrow]

Has anyone brought up the pellet thing before?

I believe Graham Elliot has brought it up previously but I cant remember whether it was on here or BFW.

 

[Keith M]

I used to regularly catch Barbel from different places on the Kennet, it was a prolific water not only for its barbel but also for its other fish including roach, Dace, Chub and trout; it used to have pure gravel on the bottom and an abundance of streamer weed and cabbages, but I'm told that the barbel have diminished quite a lot with only certain areas producing a few large barbel and the streamer weed has all but disappeared in some places and the flow has decreased there is lots of silt and the depths are lower and abstraction is at a peak; no wonder the barbel have started to die out in various places on the river.

I now fish the upper reaches of the Lea which is prolific for Barbel, Chub, Dace and roach etc. The bed is very gravelly and there are lots of good fish loving features thanks to the clubs efforts over the years but a few miles further downstream nearer to Welwyn Garden City the bed Is very silty and the barbel are very scarce around there,

Keith Spears told me once that by the time the water in the Lea reaches the Thames every drop of water has been through at least five human beings through water abstraction.
I don't doubt this as the levels; even in the winter; sometimes gets extremely low.

One thing that doesn't help is that most of the rivers that used to have prolific catches of barbel in them but now have a reduced number of barbel (Ivel, Gt Ouse, Kennet, Avon, Stour, and lower Lea) have otters, which although this may not be the main reason could be a contributory factor along with the reduced flow and silting up of the bottoms caused by abstraction. NB: We haven't seen any otters on the prolific upper Lea yet so once they arrive we can see if they make any difference to our barbel stocks. I suspect it will be detrimental to the quality of our catches; I just hope I am wrong.

I'm no expert but that is how I see it anyway.

Keith

 

[tigger]

As Keith has just said the rivers he fishes have reduced flow and weed etc, mainly due to extraction. What a lot people don't realise is that some species of fish eggs/spawn need to have clean well oxygenated water passing over them in order for them to develop and hatch. Lower levels means less flow which will be low in oxygen and also allow silt to cover spawning grounds which smothers the eggs! It won't take long for this to reduce numbers of fish of any kind. On top of that even if they do hatch they then need the right size/kind of food to grow on to the next stage of their lives and if the river isn't thriving as it should be these very important creatures may not be there or be there in reduced amounts, so if there's a shortage of that food then there's a missing link and that's not good news for fish recruitment and could reduce or even exterminate whole species of fish in a very short time....the predators will go the same way as the fish only quicker!
Personally I have no problem with predators taking fish, they've evolved naturally over millions of years to do so and imo they will only survive in the numbers that the fish stocks allow them too. Don't forget were only playing at catching fish, the pred's are trying to survive and have a lot more to loose than we anglers have if the shat hits the fan!
Obviously the real problem is human beings who are actually blatantly destroying the world, let alone the anglers pleasure/hobby of catching some fish. At the end of the day money talks and the people with the money are in control of pretty much everything so if they decide to make a little less profit by reducing pollution and extraction then the rivers will have more of a chance....I doubt they will though as they're greedy ****s and they'll always have a bullshat answer at ready to prove they arn't to blame for anything .

 

[theartist]

I used to regularly catch Barbel from different places on the Kennet, it was a prolific water not only for its barbel but also for its other fish including roach, Dace, Chub and trout; it used to have pure gravel on the bottom and an abundance of streamer weed and cabbages, but I'm told that the barbel have diminished quite a lot with only certain areas producing a few large barbel and the streamer weed has all but disappeared in some places and the flow has decreased there is lots of silt and the depths are lower and abstraction is at a peak; no wonder the barbel have started to die out in various places on the river.

I now fish the upper reaches of the Lea which is prolific for Barbel, Chub, Dace and roach etc. The bed is very gravelly and there are lots of good fish loving features thanks to the clubs efforts over the years but a few miles further downstream nearer to Welwyn Garden City the bed Is very silty and the barbel are very scarce around there,

Keith Spears told me once that by the time the water in the Lea reaches the Thames every drop of water has been through at least five human beings through water abstraction.
I don't doubt this as the levels; even in the winter; sometimes gets extremely low.

One thing that doesn't help is that most of the rivers that used to have prolific catches of barbel in them but now have a reduced number of barbel (Ivel, Gt Ouse, Kennet, Avon, Stour, and lower Lea) have otters, which although this may not be the main reason could be a contributory factor along with the reduced flow and silting up of the bottoms caused by abstraction. NB: We haven't seen any otters on the prolific upper Lea yet so once they arrive we can see if they make any difference to our barbel stocks. I suspect it will be detrimental to the quality of our catches; I just hope I am wrong.

I'm no expert but that is how I see it anyway.

Keith

There's the answer to the question I asked early on and I think we all know the answer and it's down mainly to predators and abstraction. Why else do the huge numbers of stocked barbel not show each year on the rivers mentioned.

Incidently the club that runs the upper lea stretches pumps the gravel clean each year and has no otter or cormorant issues (Yet) it also has water below a sewage works and sees more pellets per cm2 of water than any river in the country - rest assured on that fact

I'd rather not go down the test scenario Keith mentions then we will all look at each other dumbfounded that it was predators and abstraction after all, much easier to blame pellets mg:

 

[thecrow]

(Ivel, Gt Ouse, Kennet, Avon, Stour, and lower Lea) have otters, which although this may not be the main reason could be a contributory factor along with the reduced flow and silting up of the bottoms caused by abstraction

I have been reading about what is called "gravel jetting" its done by the EA to remove silt from river gravel beds, its interesting that some reports say that the effect only lasts a short while and it makes one wonder where all the silt from one bed ends up after being removed from a bed.

I have also read that a crayfish trapper on the Kennet always finds 5-10 mm of silt on his traps that he checks every other day.

 

[lutra]

Shouldn't think any of you would have a clue what the naturaly sustainable levels of barbel are (if at all) in the rivers your talking about. Just the levels they were best stocked to in recent years. So judging a decline is just how long is a piece of string.

 

[sam vimes]

I suspect that what many came to expect as normal and natural was anything but. Populations in many waters may well have gone too far to the other way. Provided the rivers concerned are in a decent enough state, some kind of equilibrium should be attainable, eventually, even if a little help is required. However, I suspect that those of us that got used to high stock levels and huge fish are likely to be disappointed if they think they'll see the like again.

I'm not one of those that lay all the blame for such declines on otters. No doubt they have had an impact on some rivers, but there are many more factors. Otters don't stop fish spawning, reduce fish fertility, decrease flow rates, increase silting or eat fry/eggs.

 

[john step]

Has anyone brought up the pellet thing before? I've been told about it in carp lakes, but carp aren't barbel, they seem to stand much more pollution and suffer less decline.

Maybe rivers like the Trent will become huge carp venues in the future.

I spoke to one chap that only fishes for carp on the Trent, and has been doing so now for several years he told me.

It's a very sad situation.

Maybe they will be carp venues AGAIN as there were more years ago.

 

[Phil Heaton]

I don't think there's just one specific reason, but I believe that the ever increasing numbers of crayfish are high on the list of possible causes. They are eating many eggs reducing the numbers of fish reaching maturity, unfortunately this is a downward spiral as the increase in crayfish numbers means even less successful recruitment of the fish eggs.