Kennet Chub Weight 'Progression' since 1982

[Phone]

Steve,

 

www.anglingtrust.net/core/core.../download.asp?id...EA...

 

I'd bet some 2014 data is available. In fact rather than the Angling Trust I'd bet the data is available directly from EA. I just didn't mess with searching for it.

 

Phone

[Steve Walker]

Again that wouldn't apply to the Thames, where in the summer you can't get a bait to the bottom because of all the fish! That may have an impact on other waters though.

You could still have very large numbers of small fish being spawned, you would still have massively more fry produced than the river could ultimately support, just with fewer making it through to the size where they are cormorant-proof.

 

Not saying that cormorants are the cause of the effect, just floating a hypothesis.

[Steve Walker]

Steve,

 

www.anglingtrust.net/core/core.../download.asp?id...EA...

 

I'd bet some 2014 data is available. In fact rather than the Angling Trust I'd bet the data is available directly from EA. I just didn't mess with searching for it.

 

Phone

Linky no worky?

[Phone]

Steve,

 

Not for me either - it was a PDF file is about all I remember.

 

Phone

[Kappa]

I wonder if crays predation of spawn could also be a major factor.

 

As per Steve I wonder if there are fewer fish generally and therefore the average size is larger due to lack of competition plus beyond a certain size they can then get huge by eating the crays.

[Kappa]

Also would be great to get your raw data Chris as averages could be hiding some interesting trends e.g. different year groups etc.

[Latimeria]

Would be interesting to see EA survey data, though any survey method is itself only ever an estimation.

 

It's very hard to prise out of them (even though it's "our" data), and at best it'll be delivered as raw data, which then has to be analysed. Took me around a year to get hold of some for rivers round here, and it was presented in a form that made it as hard as possible to make anything of it. There can also be real issues with the frequency of the sampling, insufficient to form any kind of picture.

Separate topic, but there needs to be a dramatic change in the relationship between EA Fisheries and anglers, we are their clients/customers after all.

[Phone]

All,

 

Just speculation on my part but rather than look to natural predation events like this are surely still to blame.

 

""""Thousands of fish have died after large amounts of storm sewage flooded into the River Thames.""""

 

""""Release of whey into River Dee; fish killed: 100,000 fish; species killed: Salmon, trout, roach, perch.""""

 

and for Vagabond """"The Great Smog of 1952 - It is known to be the worst air-pollution event in the history of the United Kingdom with water DO dropping to 1%""""

 

Phone

[Steve Walker]

Historic serious pollution can give you a temporary period of very impressive fishing as the river recovers and a small population recolonises it, but none of these rivers have suffered that scale of disaster. Less severe pollution does not tend to selectively spare the larger fish. Cormorants and crays are suspects only really because their numbers have grown enormously during the timescale we are talking about.

[Steve Walker]

It's also possible that these things are simply naturally cyclical.