Electrozapping fish

[Guest TerryL]

I know it keeps coming up and the louder people think they know all about it but there are so many variables in this electrocution in water business.. Does the James Bond trick of dropping an electric fire into your spouses bath really work, I am not sure that it would..

 

Electrocution of course depends on attaining a sufficient voltage differential between the head and the feet.. So larger creatures are far more vulnerable than small ones, so many times I have heard "It's the amps that kills you, not the volts" that very hackneyed sentence makes very little sense either.

 

So in theory, pass a current through a pool in Africa and you will get a few dead Alligators and thousands of tiddlers will be unaffected ? anyway pure water is a good insulator so how grimy has the water got to be.

It is amps x time that kills. In water you become part of the circuit if you are in the path because your body resistance is lower than the water. Low currents will paralyse the muscles and cause you to drown first if the current remains on for long enough. A high enough voltage and short enough distance will overcome the resistance of fresh water with sufficient milliamps. Electricity can stop the heart or burn you internally and externally, take your pick!

 

I'm just running a bath for you!

[John Orentas]

It is amps x time that kills. In water you become part of the circuit if you are in the path because your body resistance is lower than the water. Low currents will paralyse the muscles and cause you to drown first if the current remains on for long enough. A high enough voltage and short enough distance will overcome the resistance of fresh water with sufficient milliamps. Electricity can stop the heart or burn you internally and externally, take your pick!

 

I'm just running a bath for you!

 

 

That is just the sort of ill-considered response I had in mind, just how do you control the current that passes through a body.. It is usually accepted that you must have a voltage difference of two sides of the heart.. As I stated in my first post 'fresh water' (presumably pure) is an insulator so where does that leave us.

 

Anyway this glib volts and amps thing, does that mean a car battery will kill me (plenty of amps there) or how about touching a spark plug conductor will that do the job (lots and lots of volts there).. I routinely handle both of those things, why am I not dead ?

Edited November 4, 2008 by John Orentas

[Guest TerryL]

That is just the sort of ill-considered response I had in mind, just how do you control the current that passes through a body.. It is usually accepted that you must have a voltage difference of two sides of the heart.. As I stated in my first post 'fresh water' (presumably pure) is an insulator so where does that leave us.

 

Anyway this glib volts and amps thing, does that mean a car battery will kill me (plenty of amps there) or how about touching a spark plug conductor will that do the job (lots and lots of volts there).. I routinely handle both of those things, why am I not dead ?

I'm not sure what you mean by ill-considered when it's fact. You control the current by the voltage, more voltage if the resistance is high like freshwater but it's not exactly an insulator because conditions can vary. Just 50 volts can overcome the body resistance sufficiently.

 

You would get the same effect if you were to hold a resistor in each hand and connect each to the live mains conductors, the higher the resistance the less you would feel but the more the resistance the more it will affect you until the current is high enough to do you harm for long enough. You have no control over that if you are swimming.

 

If you connect enough batteries together to make at least 50 volts, that can kill you in the right conditions. Low voltage = minimum current x maximum time.

 

If you can hold on to an ignition lead for long enough it will also kill you. High voltage = maximum current x minimum time.

[Nightwatch]

When I was in the navy, on one ship we had a triple mortar launcher on the strern. We used to practice firing this thing now and again, when we did the caterer was told so that we would have fresh fish for the next few days.

[jeb]

Also Zander are an introduced species that need to be culled.

 

Been fishing long Tenchy ? suspect your a match angler and obviously dont give a toss for any other anglers interests. Zander have been established for over 100 years a bit longer than you I expect although with that attitude maybe not.

[wonderdust]

Been fishing long Tenchy ? suspect your a match angler and obviously dont give a toss for any other anglers interests. Zander have been established for over 100 years a bit longer than you I expect although with that attitude maybe not.

 

 

Zander & Crayfish.

Zander

Zander are classified as a non native species under the Import of Live Fish

Act, BW keep these fish in the canal under licence issued under this act.

We have to use our best endeavours to remove zander, for example all

zander caught in fish rescues are removed from the canal and destroyed.

Additionally in the south east business unit BW undertake an annual zander

cull as agreed with the Environment Agency in documents such as the

Cherwell Local Environment Agency Plan and the Cherwell Fisheries Action

Plan and are encouraged to do so by DEFRA.

The current geographical distribution of zander in the south east business unit

is as follows :

North Oxford. Whole length.

Grand Union/ Oxford dual Length. Braunston to Napton

South Oxford Napton to Banbury

[carlt]

All well and good but the annual cull merely strengthens the remaining stock. You are weeding out the fish who take longer to recover from the stunning.

 

The numbers culled each year remain constant which means, despite your efforts, the attempt to control an established population, of a successful species, is failing.

 

If the population is left to fend for itself, you may well see a reduction in numbers as natural selection takes a bit longer to weed out weaker stock, than unnatural selection.

 

The current geographical distribution of zander in the south east business unit

is as follows :

North Oxford. Whole length.

Grand Union/ Oxford dual Length. Braunston to Napton

South Oxford Napton to Banbury

Just as a matter of interest...How do you stop them turning South, at Braunston Turn?

[jeb]

Zander & Crayfish.

Zander

Zander are classified as a non native species under the Import of Live Fish

Act, BW keep these fish in the canal under licence issued under this act.

We have to use our best endeavours to remove zander, for example all

zander caught in fish rescues are removed from the canal and destroyed.

Additionally in the south east business unit BW undertake an annual zander

cull as agreed with the Environment Agency in documents such as the

Cherwell Local Environment Agency Plan and the Cherwell Fisheries Action

Plan and are encouraged to do so by DEFRA.

The current geographical distribution of zander in the south east business unit

is as follows :

North Oxford. Whole length.

Grand Union/ Oxford dual Length. Braunston to Napton

South Oxford Napton to Banbury

 

And that makes it right does it ?

It has been proven time and again culling does not and will not work.The only reson BW are continuing this cull is purely for finacial gain in order to appease some of the clubs that rent certain stretches. These clubs are 30 years behind and forward thinking clubs know that the zander (and pike ) will settle into a natural order with no adverse affect on the fishery. This in return produces specimen sized fish which then increses membership. Tinca Steve got my back up because quite simply no angler should advocate the culling of any fish.

[wonderdust]

All well and good but the annual cull merely strengthens the remaining stock. You are weeding out the fish who take longer to recover from the stunning.

 

The numbers culled each year remain constant which means, despite your efforts, the attempt to control an established population, of a successful species, is failing.

 

If the population is left to fend for itself, you may well see a reduction in numbers as natural selection takes a bit longer to weed out weaker stock, than unnatural selection.

 

 

Just as a matter of interest...How do you stop them turning South, at Braunston Turn?

 

Remember this quote? An invasive species that comes over naturally is not being criticised. Grey squirrels were introduced by man.

 

Whats the difference?

[carlt]

No difference and, if you search "squirrel" under my forum name you will see why. For example:

 

It's interesting that, despite prophesies of mass extinctions of fish, when the zander arrived, the disappearence of the red squirrel because of the grey and the wiping out of the otter, blamed on the mink, these tragedies haven't happened.

 

Fisheries are shouting about shootin Cormorants, but still reporting big catches.

 

Nature changes. Nature balances itself out. Man's interference upsets this balance, but only temporarily.

 

Leave the Magpies be, they are not to blame for their success, nor responsible for the decline in songbirds.

 

There is also a long running thread, somewhere involving myself and Chris w on the relative merits of culling grey squirrels (he shoots 'em, I think he's wasting his time).

 

Selective editing of my quotes does not prove your point.

[ditchcrawler]

No difference and, if you search "squirrel" under my forum name you will see why. For example:

 

 

 

There is also a long running thread, somewhere involving myself and Chris w on the relative merits of culling grey squirrels (he shoots 'em, I think he's wasting his time).

 

Selective editing of my quotes does not prove your point.

Back on electric fishing, This video is quite informative http://uk.youtube.com/watch?v=LNRYUnvpK58&....com/index.html

[carlt]

Back on electric fishing, This video is quite informative http://uk.youtube.com/watch?v=LNRYUnvpK58&....com/index.html

that isn't how they do it, in Braunston!

[dor]

As I understand it, the fish swim towards one of the electrodes rather than being completely stunned. This is what appears to be shown in dcs video.

 

For an alternative method of fishing, try:

 

http://uk.youtube.com/watch?v=9ZSBfULigM4

[carlt]

The electrofishers on the Oxford have long poles with cables dangling from them. These stun the fish (in large numbers) unlike the French "Pied Piper" method.

 

The men (usually in balaclavas, to hide their identity) then scoop up the zander and the others swim off, unharmed.

[Lesd]

And that makes it right does it ?

It has been proven time and again culling does not and will not work.The only reson BW are continuing this cull is purely for finacial gain in order to appease some of the clubs that rent certain stretches. These clubs are 30 years behind and forward thinking clubs know that the zander (and pike ) will settle into a natural order with no adverse affect on the fishery. This in return produces specimen sized fish which then increses membership. Tinca Steve got my back up because quite simply no angler should advocate the culling of any fish.

 

Well said sir !

[chris w]

.................... why am I not dead ?

Based on some of your answers on this Forum................. no, don't go there Chris

[paulcatchpole]

.................... why am I not dead ?

 

Because, like the murderous man collecting tickets on the bus, you're a bad conductor...

 

Boom boom.

 

[tinca steve]

Right ----- I have the right to believe that species that are introduced illegally should be removed.Just in case this happens !!!!!

 

 

http://uk.youtube.com/watch?v=2ChwJiKKBdA .Please watch until the end and you will see why.

 

 

I am a specialist angler, I target big fish of several species throughout the year.

 

 

I eat smoked fish and crayfish tails.

 

 

Our native crayfish is nearly extinct.

Our native red squirrel is nearly extinct.

Need I say more.

 

And as a final word the Zander is now in the River Lea and Stort. I have caught them.

[jeb]

Right ----- I have the right to believe that species that are introduced illegally should be removed.Just in case this happens !!!!!

 

 

http://uk.youtube.com/watch?v=2ChwJiKKBdA .Please watch until the end and you will see why.

 

 

I am a specialist angler, I target big fish of several species throughout the year.

 

 

I eat smoked fish and crayfish tails.

 

 

Our native crayfish is nearly extinct.

Our native red squirrel is nearly extinct.

Need I say more.

 

And as a final word the Zander is now in the River Lea and Stort. I have caught them.

 

My final word .... Noddy

[Janet S]

Don't you think that was a bit harsh Jeb?

 

Janet

[jeb]

Don't you think that was a bit harsh Jeb?

 

Janet

 

Hi Janet,

No not really,it was an affectionate term we used to use in the 70s in the early pioneering days of specimen hunting for someone who used to come along and make out he knew and caught the lot. 5 mins were more than enough to suss them.

[tinca steve]

Specialist is not Specimen.

I have been angling for 50 years, yes I matched fished for 22 years but then decided to specialise my time through the year for tench, crucian,bream,roach,chub and barbel.

[tinca steve]

A touch of specialist angling with a pin - nice isn't she !!

 

 

[fuzzyduck]

That's a very pretty fish.

 

What is it?

 

did it taste nice?

[carlt]

Is it native?