Hormones getting into fish.

[Trevor Summerfield]

Some time back there were a few articles in the comics regarding sex hormones that were getting into our rivers and then being taken up by its inhabitants. In this case Barbel. Considering the poor spawning and lack of juvenile fish, is there still a case for screening hormones at the sewage plants in the UK? And is it possible?.. Does any angler know if further research has been done on this issue?

 

[Paul Bullinger]

Some time back there were a few articles in the comics regarding sex hormones that were getting into our rivers and then being taken up by its inhabitants. In this case Barbel. Considering the poor spawning and lack of juvenile fish, is there still a case for screening hormones at the sewage plants in the UK? And is it possible?.. Does any angler know if further research has been done on this issue?

Trevor, not just hormones but a group of over 9,000 individual "nasties" called "forever chemicals" exist in our waterways and, in many cases, our drinking water. These are chemicals from things like non-stick pans to make-up.
No-one knows the harm they cause to fish, invertebrates or indeed, us.
I think the next big "scandal" will be when Joe Public finds out its not obvious pollution, such as sewage, that's in our rivers and seas, but these unseen chemicals that NEVER break down.

 

[Trevor Summerfield]

What I am getting at is fish changing sex, which I believe is happening, plus the effect this has on spawning populations. Fish usually spawn with one female accompanied by a number of males. So if a female is accompanied by a number of male fish affected by sex hormones in its environment how does that affect the success rate of eggs being fertilized? If the results are poor or zero even then years classes of fry just do not happen. Obviously, this becomes clear when Barbel populations are seen to be in decline in many of our rivers.

 

[David Clewer]

Many years ago there was a report that oestrogen, from the contraceptive pill, was changing roach in a northern river from male to female, impacting on spawning. Heard very little about it since and don’t know whether it was genuine or not. These days you don’t seem to hear about such things as the emphasis has changed to sewage and agricultural/ farm pollution although the story about eels in the Thames being addicted to cocaine got quite a bit of coverage a while back.


Dave

 

[Graham Elliott]

I reported on here some time ago that a Professor Franklin had found roach had become Asexual on the River Loddon below the ouflow from the Sewerage plant at Charvil. This report from around 1960.

A treatment plant that I had reported many times since as I watched ladies tampons exit the plant anytime the river had raised levels.

I also had concerns that bait being used for salmon feed could infant contain growth hormones and ingredients to reduce natural spawning activity, and associated agression within the netted pens.

 

[Ash Gould]

Hormone distortion still widespread in fish | Brunel University of London

www.brunel.ac.uk

 

[Trevor Summerfield]

What I am getting at is fish changing sex, which I believe is happening, plus the effect this has on pawning populations. Fish usually spawn with one female accompanied by a number of males. So if a female is accompanied by a number of male fish affected by sex hormones in its environment how does that affect the success rate of eggs being fertilized? If the results are poor or zero even then years classes of fry just do not happen. Obviously, this becomes clear when Barbel populations are seen to be in decline in many of our rivers.

Hormone distortion still widespread in fish | Brunel University of London

www.brunel.ac.uk

 

[Trevor Summerfield]

The Science speaks for itself. Why are anglers not jumping up and down regarding this? another important issue that anglers ignore at their peril.

 

[Chris Guy]

The Science speaks for itself. Why are anglers not jumping up and down regarding this? another important issue that anglers ignore at their peril.

Anglers were jumping up and down re the sewage issue, no one took us seriously. Only when canoeists and wild water swimmers took it to the public, did any media really take notice.
General public don't really care about freshwater fish or angling