Calculating by measurment

Beaker · Jan 31, 2014

How do you calculate the wieght of a fish by measurment? The reason I ask is that I managed to get out last Tuesday to a local park lake, the first trip since November because of work and a ruptured disc in my lower back.
I caught a decent pike but did not have any scales and there was no one else fishing. I borrowed a tape measue of a council workman and measured it. It was 40.3 inches long and 19.7 inches at the fattest girth, could someone tell me what the formula is for estimating the weight, cheers.

richiekelly · Jan 31, 2014

There are some on the net just google pike length to weight,

From your figures I would say the fish was 18 to 20 lbs.

beerweasel · Jan 31, 2014

https://www.google.co.uk/url?sa=t&r...-b4Zk_jDlELGe7sew&sig2=7_jtIjrxxlY6iFBw8tkfnw

mick b · Jan 31, 2014

As Blanker says, big 18 or scraper 20, personally Id give you it as a scraper, especially as you've not caught that many biggish Pike.

Well done, nice fish...:w

terry m · Jan 31, 2014

Those numbers suggest a mid-upper double to me. The girth is not huge.

Nevertheless a decent fish.

Derek Gibson · Jan 31, 2014

I'm one of those sad people who for many years kept length, girth and weight records of pike, so I have no hesitation in agreeing with Blanker and Mick B, 18 to 20 lbs. Possibly the higher figure.

jacksharp · Feb 1, 2014

When salmon fishing it's not considered good form to weigh them, particularly if they are going back, so there are standard tables produced that give weights based on length and girth. I have one, laminated, in the pocket of my chest waders.

It doesn't get used much!

theartist · Feb 1, 2014

jacksharp said:
When salmon fishing it's not considered good form to weigh them, particularly if they are going back, so there are standard tables produced that give weights based on length and girth. I have one, laminated, in the pocket of my chest waders.

It doesn't get used much!

I got a laminated rod licence in my pocket but that doesn't see the daylight often either

On subject I had a pike on a trout beat that was that length exactly and it did do 20 just but it was the fattest pike I'd ever seen

Derek Gibson · Feb 1, 2014

Interestingly enough there has been a scale for the weight of pike available for many years. It is called the ''Mona'' scale, and dates back many years. Many of us of a certain age, and disposition used that very scale to test out the validity, prior to weighing.

Unfortunately, ''Mona'' did not include girth measurements in his scale, basing his conclusions purely on length alone. But his tables were fairly accurate nontheless. That is, untill you reach ''giant'' pike proportions of thirty five pounds plus.

''Mona'' could not have conceived the proportions of some of today's trout water pike, or the growth rates.

Still, his scale for pike up to around mid twenty's is roughly accurate. But today we need to weigh them, if we suspect it really is a fish of importance.

Beaker · Feb 1, 2014

mick b said:
As Blanker says, big 18 or scraper 20, personally Id give you it as a scraper, especially as you've not caught that many biggish Pike.

Well done, nice fish...:w

That makes two of us Mick:wh
I am going to say 19lb, the reason I did not weigh it was I was so unorganised and the welfare of the fish was of more importance. Just to say though it was a beautiful fish whatever the size and I am happy in the fact he (or she) is swimming around Coate water.

---------- Post added at 14:08 ---------- Previous post was at 14:08 ----------

mick b said:
As Blanker says, big 18 or scraper 20, personally Id give you it as a scraper, especially as you've not caught that many biggish Pike.

Well done, nice fish...:w

That makes two of us Mick:wh
I am going to say 19lb, the reason I did not weigh it was I was so unorganised and the welfare of the fish was of more importance. Just to say though it was a beautiful fish whatever the size and I am happy in the fact he (or she) is swimming around Coate water.

nicepix · Feb 1, 2014

Last summer I was catching wels catfish averaging 19lb to just over 22lb. They were all from the same stretch of river and all the fish were healthy and of good proportions. The heaviest fish was 113 cm and the lightest fish was 119cm. According to American length to weight tables the fish should have been almost double that weight

Calculating by measurment

Beaker

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richiekelly

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beerweasel

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mick b

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terry m

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Derek Gibson

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jacksharp

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theartist

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Derek Gibson

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Beaker

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nicepix

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