Otters? Cormorants ? what about Eostrogen pollution

[Tim Lennon]

How many fish would you suppose survive from the last Avon stocking?

I've no idea. That's why I asked you to expand!

I seem to recall that the last lot to go in were dye marked. Would the dye marking still be visible? Unless the dye marking is retained it would be impossible to know for sure, wouldn't it?

I suspect, though, that the stocked juveniles at the time of stocking would have outnumbered natural juveniles of the same age. Therefore logic would suggest that if any barbel survived of that year class they would be more likely to be stocked fish, unless the stocked juveniles suffered a greater mortality rate than the naturals.

 

[Damian Kimmins]

It all depends how long ago that was though. For as long as I have been fishing the Avon it's not been possible to stock the river, on account of them not being considered native to the river.

 

[Tim Lennon]

It all depends how long ago that was though. For as long as I have been fishing the Avon it's not been possible to stock the river, on account of them not being considered native to the river.

From memory I would say it was around 2002. I believe fish were introduced at a number of locations, including Winkton, and were dye marked. They were only small fish, and I recall being sceptical at the time about their chances of survival. With the potential life span of barbel they could (should?!) still be around...

 

[Damian Kimmins]

It's not as far in the past as I thought it might have been then. I would suggest given the length of virtually unfished river upstream any survivors might be on the Royalty.

 

[Roger Carswell]

I remember fishing a match at Bridgnorth on the Severn in the early seventies. I caught 38 barbel on the float with a single caster as bait - they collectively weighed just under 18lbs!

 

[Tim Lennon]

I have an even more unpalatable theory regarding a contributory factor to the accelerating demise of barbel in those rivers where there is insuffucient natural recruitment from successful breeding.

Q) What percentage of hooked/captured barbel die as a direct or indirect result of being hooked/captured?

A) I don't know. But even if the answer is a very low percentage, it would still have a dramatic long term effect on fisheries where there is already a low population of fish and insufficient natural recruitment is taking place. Do the maths!

I think the effect of this has been increased by there being an increasing number of increasingly successful barbel anglers, mainly as a result of the introduction of pellet. Also, as I've previously suggested on BFW, I think the effect will be greatly increased on fisheries where otters are present.

 

[Damian Kimmins]

I dont know Tim, for any species having evolved into such a specific environment, slight changes must present difficult hurdles.

 

[Ian Crook]

I would agree with Tim. The biggest common factor in line with difficulty in catching barbel (I will not use the term "reduced numbers" as on many rivers this is simply not the case) is the dramatic rise in "specimen barbel anglers". You can even track this across rivers. For example the Kennet got difficult around 2008 and many of those anglers switched to fishing the Wye which was easy as pie (and that rhymes). 5 years on and many stretches of the Wye having been absolutely hammered, it too is showing signs of difficulty, which is driving people to also say the numbers of fish has reduced.

 

[Joe Fletcher]

In 2011 when we had the drought there was a stretch on the Lower Severn well known for producing double figure fish in the past and in that year all the Barbel seem to disappear and you hardly ever saw any on fishing the stretch .
Then when we had the rain and the floods last summer and river was out of its banks most of the time .
People were catching loads of doubles and once the word had got around you had a job to find a spot to fish .
So where did all those fish come from ? That seemed to vanish the previous year ?

 

[Andrew Burt]

Andrew, I agree with much of what you say, in fact water coloured by certain discharge is probably better for the fish. But its the chemicals introduced, in the birth pill for example that is my main concern.

These are fairly recent changes and cant be compared with no doubt the lower levels then.

When you see womans tampax floating straight out of a water treatment plant it can't be good.

Grahamh[/

I don't know exactly how much effect birth control pills will have. I do know they have been around for over 50 years. I also know the fishing was better and I saw more wildlife before the EA started dictating the environment they wanted. Most raw sewage I have seen in waterways has been as a result of storm drains flooding. A healthy river will easily cope with some sewage. Might not be pleasant but it is certainly not harmful. However, sterilize the water, remove bankside cover, dredge, straighten and drain then fill with salt to balance pH, add some flockulant to make sure anything that has escaped your filtration can't get away. Then you've really helped the environment.

 

[Andrew Burt]

I quite agree Andrew. Talking to an operative on a southern water site on the south coast a few years ago, with the investment they had made in treating effluent in vast bubbling tanks (activated sludge lanes?), local shellfish populations had been decimated. I was shown a bottle of final effluent and you could not tell the difference between that and Evian. Maybe we will introduce minerals into it as a part of the treatment process?

A few years ago there was talk of at least a partial change to allow at least some treated effluent back in. Maybe additives could be the answer.

 

[Damian Kimmins]

I would agree with Tim. The biggest common factor in line with difficulty in catching barbel (I will not use the term "reduced numbers" as on many rivers this is simply not the case) is the dramatic rise in "specimen barbel anglers". You can even track this across rivers. For example the Kennet got difficult around 2008 and many of those anglers switched to fishing the Wye which was easy as pie (and that rhymes). 5 years on and many stretches of the Wye having been absolutely hammered, it too is showing signs of difficulty, which is driving people to also say the numbers of fish has reduced.

That's interesting Ian, but I would suggest its purely coincidental. Most stretches I know fishing much better, comparatively speaking, are those much busier. Regardless, I do miss the old boy pleasure anglers from our banks - some great characters.

 

[Damian Kimmins]

In 2011 when we had the drought there was a stretch on the Lower Severn well known for producing double figure fish in the past and in that year all the Barbel seem to disappear and you hardly ever saw any on fishing the stretch .
Then when we had the rain and the floods last summer and river was out of its banks most of the time .
People were catching loads of doubles and once the word had got around you had a job to find a spot to fish .
So where did all those fish come from ? That seemed to vanish the previous year ?

On a river like the Avon, on certain days, you'd be forgiven for thinking it contains no fish whatsoever. Come the moment that gives them a little confidence however, and it's like the burst of spring colour - it all comes to life once again. Fish are vulnerable from all kinds of threats. Swimming and feeding readily over a baited patch in front of me as the sun started falling, their relaxation as conditions changed was shown as the barbel soon vacated the area. Experienced that more than once.

 

[David Gauntlett]

I don't know exactly how much effect birth control pills will have. I do know they have been around for over 50 years. I also know the fishing was better and I saw more wildlife before the EA started dictating the environment they wanted. Most raw sewage I have seen in waterways has been as a result of storm drains flooding. A healthy river will easily cope with some sewage. Might not be pleasant but it is certainly not harmful. However, sterilize the water, remove bankside cover, dredge, straighten and drain then fill with salt to balance pH, add some flockulant to make sure anything that has escaped your filtration can't get away. Then you've really helped the environment.

Andrew, I agree that a certain level of organic effluent seems to benefit at least some species of fish....those that have evolved to thrive in the mid and lower reaches of rivers, areas which are naturally eutrophic, roach, bream and carp being prime examples. However, those fish that evolved to live in the upper reaches, or in chalk streams for instance...do not benefit from that effluent, which is why fish like trout and grayling tend to slowly disappear when these type waters start to receive effluent of that nature....which happens as the human population in countries grows.

Again, I agree that 'a healthy river will easily cope with some sewage'....but how many of our rivers ARE healthy....and how many are actually teetering on the edge of their ability to deal with the levels of such pollutants already present? And how much is 'some'? Huge stretches of many of our rivers are regularly severely damaged...some stretches of smaller rivers being completely wiped out for some time...by the deoxegenating effects of pollution events involving raw sewage. Which of course is the logic behind the much vaunted 'Thames Super Sewer'...to avoid the release of such nasties into the Thames every time it rains! So, I think your point that 'some sewage is certainly not harmful' is a bit of a sweeping (not to say inaccurate ) statement....in my opinion. It is certainly true though, that the madness you describe in your last two sentences has caused localised ecological disasters.

However, I feel it is the increasing numbers of chemical pollutants, some of which we may never have heard of yet (let alone be aware of the dangers they represent)...that are the issue that is the most worrying. You can't test for things you have no knowledge of...and we know all too well how much trust we can place in big business when profit and shareholders bonuses are involved.

Which I guess brings us back to the intent at least of the original post.

Cheers, Dave.

 

[Andrew Burt]

water treatment

Andrew, I agree that a certain level of organic effluent seems to benefit at least some species of fish....those that have evolved to thrive in the mid and lower reaches of rivers, areas which are naturally eutrophic, roach, bream and carp being prime examples. However, those fish that evolved to live in the upper reaches, or in chalk streams for instance...do not benefit from that effluent, which is why fish like trout and grayling tend to slowly disappear when these type waters start to receive effluent of that nature....which happens as the human population in countries grows.

Again, I agree that 'a healthy river will easily cope with some sewage'....but how many of our rivers ARE healthy....and how many are actually teetering on the edge of their ability to deal with the levels of such pollutants already present? And how much is 'some'? Huge stretches of many of our rivers are regularly severely damaged...some stretches of smaller rivers being completely wiped out for some time...by the deoxegenating effects of pollution events involving raw sewage. Which of course is the logic behind the much vaunted 'Thames Super Sewer'...to avoid the release of such nasties into the Thames every time it rains! So, I think your point that 'some sewage is certainly not harmful' is a bit of a sweeping (not to say inaccurate ) statement....in my opinion. It is certainly true though, that the madness you describe in your last two sentences has caused localised ecological disasters.

However, I feel it is the increasing numbers of chemical pollutants, some of which we may never have heard of yet (let alone be aware of the dangers they represent)...that are the issue that is the most worrying. You can't test for things you have no knowledge of...and we know all too well how much trust we can place in big business when profit and shareholders bonuses are involved.

Which I guess brings us back to the intent at least of the original post.

Cheers, Dave.

David, I find the last paragraph a bit conspiracy theory and scare mongering, that there is an increasing amount of chemicals we haven't heard of entering the water. I must point out there is a big difference between industrial pollutants and sewer. We, like every other factory that discharge effluent, have regular Water Authority visits and legislation with which to comply. The thought that we would be using chemicals that even we had not heard of and then discharging them is obviously incorrect. Your point about is a waterway healthy is obviously valid. I would argue that if it were not it is largely down to the sewage treatment works. To expand on your point about trout and grayling. Is the idea or should the idea to be to produce water that is the same as a mountain spring? If so we will not have many fish in our rivers. I do not believe you think this for one minute. Trouble is we are producing a nasty version of this. As the water goes down a river it goes into a sewage plant and everything that went in is removed. Surely if we measured the biology going in and then replaced it this would produce a natural environment? At the moment this is not how it works. The health of a waterway should be measured in how well it can heal itself and sterilizing it and removing all the aerobic bacteria will prevent this happening. You can see this in these awful hole in the ground fisheries in the spring. So I believe that my point reference some raw sewage is valid. I am however only putting forward the point that a limited amount of treated sewage or appropriate substitute should be released.

 

[Lee Fletcher]

Dear Damian

You might like to look at these;

http://www.macalester.edu/academics...ts/endocrinedisrupterswebsite/articles/05.pdf

http://www.swhydro.arizona.edu/archive/V2_N6/feature4.pdf

Additional Treatment of Wastewater Reduces Endocrine Disruption in Wild Fish

Endocrine disrupting chemicals in the environment - King County Wastewater Treatment Division

Ecosystems & Environment: Wastewater Treatment | Endocrine Disruptor Research | US Environmental Protection Agency

Ecosystems & Environment: Wastewater Treatment | Endocrine Disruptor Research | US Environmental Protection Agency

This is a really good one;

http://www.brunel.ac.uk/__data/asse...ymont_Declaration_on_Endocrine_Disrupters.pdf

Treatment against this threat is possible. Its the political will that is not.

And I'm a God damn barbel fishing Tyrannosaurus.

Regards,

Lee.

 

[Joe Fletcher]

The vast majority of the public are not really concerned with what goe's on with our rivers . All they are concerned with is clean drinking and clean water to wash and shower etc etc and I bet most dont know what gets pumped in to our rivers and dont really care .
They sit in front of the tv screens and watch wild life programes about the wild life that live on and around our rivers . How many wild life programes do you see about fish ? Maybe one about Salmon from time to time ? You never see one about course fish ? and as far as they are concerned they dont see a problem with what lies beneath and most are ignorant of the problems and the state some rivers are in .
The only time the vast majority of people are concerned about our rivers when there is a threat of serious flooding to there homes .

At the moment as anglers we are all to aware of the problems that Cormorants , Otters and the Seal on the Lower Severn are causing to fish stocks . Could you imagine the public out cry if Otters were ever culled .
What will be done about Seal on the Lower Severn ? Unless you are a angler do people really care ? and will any thing be done about it ?
Was it last year that a online petition was started when it got out that the Seal at Bewdley was going to be shot ? because it was eating a few fish .
When it comes to the state of our rivers most people unless you are a angler dont care because they are not really interested in what happens below the water line ?

 

[Dave Taylor]

I have an even more unpalatable theory regarding a contributory factor to the accelerating demise of barbel in those rivers where there is insuffucient natural recruitment from successful breeding.

Q) What percentage of hooked/captured barbel die as a direct or indirect result of being hooked/captured?

A) I don't know. But even if the answer is a very low percentage, it would still have a dramatic long term effect on fisheries where there is already a low population of fish and insufficient natural recruitment is taking place. Do the maths!

Apologies for the belated comment Tim.
Some 20 odd years ago I was fishing the Throop on the last day of a regular 5 day trip and, after some 15 years of catching loads of 9's, I banked my first Throop double.
The smuggness soon turned to deep depression though as my next barbel [about 8 1/2 lbs ] was bleeding badly from inside it's throat and had two tumours on the outside of it's mouth.[ The fish had been lip-hooked ]
I stood in the river for 45 mins attempting to revive the poor fish, but to no avail, and it died on me.
That fish was, to my knowledge the only barbel fatality of my 36 years of barbel fishing,...but it left a bitter memory.
The next day, back at home, I phoned the then fishery manager on Throop and told him the sorry tale. After bending my ear for not handing in the dead barbel [Which would have been sent away for analysis ], he told me that he was aware of 35 'casualties' so far that season [ this was early sept.] and most were due to anglers trying to extract fish from impossible swims, or just failing to care for them correctly after capture.
I was naively shocked and surprised at that figure and wondered how substainable it was, even on a prolific fishery such as Throop.

One other abiding memory back then was the horrible brown slushy muck that was being deposited into that wonderful river on lower blackwater from the adjacent STW's. Most who fish rivers have wittnessed similar I suspect, but I wonder if they have seen so many chub and barbel actively feeding on it as were on the Throop,..they were loving it!

Andrew,...You are correct regarding fish keepers not using tap water,..I don't 'keep' koi, I 'keep' water!

 

[David Gauntlett]

Andrew,

Sorry my previous post was not clear, I will attempt to clarify. And Dave Taylor, I agree with your point about 'keeping water', lol. If you dropped the corals and tropical marines I keep into 'tap water'....they would be dead in seconds. You wouldn't need to look too far to find Nemo....he would be floating on the top in plain view

The point I have been trying to make all along is this....you cannot judge the quality of water, or whether it is fit for purpose....just by looking at it. If you had a glass of decent tapwater, and a glass of the synthetic sea water I take such care in producing....you would NOT be able to tell the difference by sight. I guarantee that. They would both be absolutely crystal clear....but SO very different in their make up...chalk and cheese don't even come into it

You just CAN'T say that water is bad for fish just because it is 'as clear as tap water'....any more than you can say for sure that it is good. What is good for the goose is very often NOT good for the gander. The only way to determine whether or not water is good for a particular variety of fish is to know that fishes requirements...and the EXACT chemical make-up of the water in question. My saying that the inhabitants of typical upland stretches of rivers such as trout and grayling do not like turbity, and that the typical appearance of the type of water they prefer LOOKS like tap water...was not meant to infer that it was chemically akin to tap water. Similarly, the typical lowland reach of that same river is likely to be a very different beast, with high turbidity and a totally different chemical make-up, due to the stuff it picks up on it's way to the sea...which suits the fish that evolved to live there very well....billy barbel for one

The fact that the lower reaches are frequently subject to sudden and drastic changes in chemical make-up too, due to flooding etc., means that the fish that live there are able to cope with that as well. Fish such as trout and grayling from the more stable upland areas are not so resilient to change...which is why I said that human population increases create conditions that sees the slow disappearance of such fish. Once lack of space sees towns popping up in previously sparsely populated upland areas, then obviously pollution of all types is going to start appearing in those once pristine reaches as well....end of.

Lastly, I still feel that it is quite reasonable to assume that because it is entirely possible for some awfully nasty chemicals to be invisibly dissolved in crystal clear water....then they may well be there. There are many things that the sewage treatment plants cannot and do not remove...and which will NOT show up if they are beyond the range of the testing equipment in typical use by bodies such as the EA. Obviously anyone dumping such nasties in our rivers as a cheap (if illegal) means of disposal will know what they are...I thought that went without saying. What I meant is that historically, such irresponsible ways of disposing of toxic waste was commonplace....and sadly, it still is. Ask the AT about that.

Sorry to waffle on so much...but I hope you see what I was trying to say now?

Cheers, Dave.

 

[Tim Lennon]

he told me that he was aware of 35 'casualties' so far that season [ this was early sept.] and most were due to anglers trying to extract fish from impossible swims, or just failing to care for them correctly after capture.

Hi Dave. Do you have any more information regarding these casualties? How were fish discovered to have been killed when people were trying to extract them from impossible swims? Were the corpses found tethered?