Countryfile Yesterday

[ColinW]

I don't know if it is repeated but it might be worth a look if it is on BBC's net service. There was an article about what might be a serious threat to freshwater fish stocks. Scientists report that a lot of the male fish (roach in their experiments) are not producing sperm, they have eggs growing in their testes, due to hormone levels in the sewage outflows (mainly due to contraceptive pills). The river they were concentrating on was the Trent, but it is a nationwide problem. I know it's not a new threat but I didn't realise it was so serious before.

[lutra]

Here about 7 mins in.

[gozzer]

Thanks for posting this Colin, and thank you for the link Lutra.

I usually watch the programme, but missed this weeks.

 

I'm surprised that it's had over 100 views without any comments.

 

This could effect the whole future of angling in this country, and hardly anyone seems to think it's worthy of comment! (am I really that much out of touch with todays anglers?)

 

It fit's in nicely with the 'where are all the gudgeon' thread. It also fits in with my thoughts on that thread.

 

I have long since thought that all the claims of 'cleaner' rivers were misleading. True, the collapse of industry in the 80s and 90s did reduce the amount of stuff going into our rivers. But I've suspected for some years that there were other things just as dangerous being put into them. Just because a river looks clean/clear, and it produces large fish doesn't mean that it's in a healthy state.

I've noticed that the 'pyramid' of year classes has not been present, or that it is greatly reduced.

This might not be such a problem (yet) in the more rural rivers, but for those of us that fish where it runs through a few big towns, then it certainly is.

 

I can only hope that the chemicals can be identified and dealt with, before our indigenous species are depleted beyond recovery. All some stretches will be left with then, are the 'spillages' from man made 'fisheries', or repeated restocking with 'popular' species, and I know what that means!!!

 

John.

[Steve Walker]

There was a fellow student working on this problem when I was a PhD student, 15 years ago. It's not just (or even mainly) the pill, either - there are a great many chemicals used for all sorts of purposes which are capable of acting as oestrogen mimics; detergents, plasticisers, preservatives and UV screens in sun lotion and cosmetics, flame retardants, various industrial wastes. Even some food plants (soya, particularly) contain oestrogen mimics which are excreted in the urine and can affect fish behaviour. Maybe it's all the vegetarians who are doing for the gudgeon...

[Worms]

Thanks for posting this Colin, and thank you for the link Lutra.

I usually watch the programme, but missed this weeks.

 

I'm surprised that it's had over 100 views without any comments.

 

This could effect the whole future of angling in this country, and hardly anyone seems to think it's worthy of comment! (am I really that much out of touch with todays anglers?)

 

It fit's in nicely with the 'where are all the gudgeon' thread. It also fits in with my thoughts on that thread.

 

I have long since thought that all the claims of 'cleaner' rivers were misleading. True, the collapse of industry in the 80s and 90s did reduce the amount of stuff going into our rivers. But I've suspected for some years that there were other things just as dangerous being put into them. Just because a river looks clean/clear, and it produces large fish doesn't mean that it's in a healthy state.

I've noticed that the 'pyramid' of year classes has not been present, or that it is greatly reduced.

This might not be such a problem (yet) in the more rural rivers, but for those of us that fish where it runs through a few big towns, then it certainly is.

 

I can only hope that the chemicals can be identified and dealt with, before our indigenous species are depleted beyond recovery. All some stretches will be left with then, are the 'spillages' from man made 'fisheries', or repeated restocking with 'popular' species, and I know what that means!!!

 

John.

I was thinking about the 'where have are all the gudgeon gone' thread as well. I too thought it worthy of comment I was just trying to get my head round some of the possible reasons.

 

I fish a rural river classified as 'A' quality water in that there is no industry (bar farming) on the river and very little in the way of sewage effluent discharge.

 

The fact that gudgeon were one of the fish species investigated made me sit up and pay attention. It seems that they are still unsure as to what the source of these EDC's is. I did wonder though whether some of the 'safe' chemicals used in farming may be involved? I recall about 10 years ago that concern was raised about some of the 'drenches' used for sheep that included fungicides. The result being that some of these chemicals were excreted by sheep in their droppings. This had a detrimental effect on fungus species growing in the fields.

 

I wonder if a similar 'innocent' stock/crop treatment is being washed into watercourses with a detrimental effect on some fish species.

 

Only supposition you understand, I'm not trying to lay any blame anywhere!

 

As I said in the gudgeon thread, many other species of fish have increased in numbers over the years. Perhaps some species of fish are unusually susceptible to some of these EDC's.

 

We need an AN organic chemist on the case.... any volunteers?

[Steve Walker]

Cleaning up a river is likely to alter the assemblage of fish present - there will be winners and losers. I wonder whether gudgeon are losers - they seem reasonably tolerant of poor water quality, and they feed principally on invertebrates snuffled out of the bottom.

[Worms]

Cleaning up a river is likely to alter the assemblage of fish present - there will be winners and losers. I wonder whether gudgeon are losers - they seem reasonably tolerant of poor water quality, and they feed principally on invertebrates snuffled out of the bottom.

A good point Steve but the river I fish has had the same water quality rating for the past 40 years to my knowledge. It's not navigable and has variable substrates from gravel, rock, silt, clay and sand along its length. Gudgeon could be found almost anywhere. It was the reason for the gudgeon thread really to see if other waters were affected. It seems that some are and some aren't. There's certainly no shortage of food for them, the river's crawling with aquatic invert life!

 

I wonder if reverting to fishing with a bean cane and a bent pin will make me catch more?

[BoldBear]

About 7 to 10 years ago there were reports and photographs of Barbel on the river Lea with minor deformities like extra barbels and the Pill in womens urine was blamed then as it can get through the sewage water filters.

There were also cases of fish changing sex or becoming barren caused by the hormones and the birth pill, but I havent heard of it for quite a few years now.

Edited March 3, 2009 by BoldBear

[ayjay]

About 7 to 10 years ago there were reports and photographs of Barbel on the river Lea with minor deformities like extra barbels and the Pill in womens urine was blamed then as it can get through the sewage water filters.

 

There may have been a case then but I remember similar reports much further back (in the late 80s, when I still fished at Kings Weir) which were thought to be caused by growth promoters in the pork used in luncheon meat.

[mjbarnes12]

you know what to do then chaps, deposit some testosterone into the sewage works!!!

 

sorry