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Location: Black Creek, WI | Length measurement of fish is an accepted method, and bag limits rely on them. How to properly measure the length of a fish is clearly identified by most Dept. of Natural Resources. Thus, knowing how to properly measure the length of a fish has value.... as it could mean the difference between a ticket or not. Has anyone documented how to properly measure the girth of fish? Can it be done with any accuracy and repeatability? Enough to be used for establishing "records"? If not, is there any value to a girth measurement? With catch and release so popular today, are RECORDS established by weight of any value? What good is a State Record (by weight) if there are bigger fish getting caught and released? And... if weight is the metric of choice... doesn't that promote killing a fish and conflict with the poplularity of C&R? What are your thoughts?
Edited by jlong 1/2/2013 2:50 PM
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| jlong - 1/2/2013 2:46 PM
Length measurement of fish is an accepted method, and bag limits rely on them. How to properly measure the length of a fish is clearly identified by most Dept. of Natural Resources. Thus, knowing how to properly measure the length of a fish has value.... as it could mean the difference between a ticket or not. Has anyone documented how to properly measure the girth of fish? Can it be done with any accuracy and repeatability? Enough to used for establishing "records"? If not, is there any value to a girth measurement? With catch and release so popular today, are RECORDS established by weight of any value? What good is a State Record (by weight) if there are bigger fish getting caught and released? And... if weight is the metric of choice... doesn't that promote killing a fish and conflict with the poplularity of C&R? What are your thoughts?
Unless your tape starts at 2", I don't see a lot of margin for error. But I don't see a lot of value in girth measurements. A short stocky fish with a full belly vs a longer fish that's thick all the way through, full stomach vs empty, eggs vs no eggs... Too many variables for it to have any real meaning. Even weight will vary throughout the season. But a 57" fish will never be any shorter. |
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| Even if you standardized girth... does a 55" fish with a pot belly 28" girth out-weight a fish with a 27" girth that carries the mass more proportionately head to tail? Unfortunately I think weight is where it will always be. Look at the recent Barbosa fish 58 lbs and didn't even hit 55"
Edited by IAJustin 1/2/2013 3:05 PM
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Location: minocqua, wi. | how bout a uniform tank and a displacement/volume measurement then calculation on a standard density?? |
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| jonnysled - 1/2/2013 3:09 PM
how bout a uniform tank and a displacement/volume measurement then calculation on a standard density??
Or a digital camera that calculates weight based on quasiparticle physics? |
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Location: minocqua, wi. | volume/density is no more difficult than using a measuring stick ...
math |
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Location: Madison, WI | if you assume that muskies are being caught at reasonably consistent temperatures (30-80F), you can also assume that they will have reasonably consistent body densities. (like us, they're mostly water anyway.)
build a tube 70" tall, with a 35" circumference. fill it to 60" with water.
put the muskie in the tube headfirst.
measure the water level with the muskie inside (mL of water displaced).
release the muskie.
no mucking around with girths, no dead fish, just a simple number. it ain't "cheat proof" but it's less prone to the obvious measurement errors that girth tapes seem to produce so frequently.
EDIT: i see Sled got there the same time as me.
a new start-up muskie business perhaps, Sled? "the Muskie Toob"?
Edited by lambeau 1/2/2013 3:22 PM
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Location: minocqua, wi. | lambeau - 1/2/2013 3:20 PM
if you assume that muskies are being caught at reasonably consistent temperatures (30-80F), you can also assume that they will have reasonably consistent body densities. (like us, they're mostly water anyway.)
build a tube 70" tall, with a 35" circumference. fill it to 60" with water.
put the muskie in the tube headfirst.
measure the water level with the muskie inside (mL of water displaced).
release the muskie.
no mucking around with girths, no dead fish, just a simple number. it ain't "cheat proof" but it's less prone to the obvious measurement errors that girth tapes seem to produce so frequently.
EDIT: i see Sled got there the same time as me.
a new start-up muskie business perhaps, Sled? "the Muskie Toob"?
seems logical to me mike ... send me the call-in number and we can get the design phase started. |
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| so what do we get with volume? muskies of the same volume could have different weights -correct? |
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Location: minocqua, wi. | mass density is a pretty consistent number ... the amount of error there would be less than current measurement error in my opinion.
not like there are muskies that go to the gym and do squats all day and others that sit around watching fishing shows eating potato chips. |
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| You take the same fish full of eggs she weighs 66 pounds .... she has the same volume whether or not she just ate that last 2 pound whitefish doesn't she? Put the 2 pound whitefish in her belly now she is 68 pounds. |
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Location: minocqua, wi. | put the 2 pound whitefish and you increase the volume and density doesn't change a % ...
arguing is fun tho |
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| are you assuming the fish has to expand to fit this small fish in its belly? same balloon of water vs air will have same volume different mass.. |
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Location: Madison, WI | You take the same fish full of eggs she weighs 66 pounds .... she has the same volume whether or not she just ate that last 2 pound whitefish doesn't she? Put the 2 pound whitefish in her belly now she is 68 pounds.
yes, obviously the best way to determine the weight of a fish is to WEIGH IT. the initial question was about using girth as an alternative to weighing fish. Archimedes' would suggest a better approach. (measure displaced water, multiply by standard density to determine weight.)
and the volume likely does change when fish add egg mass or eat a big meal - heck, you can usually see it with your naked eye. water displacement would find that more accurately than a girth tape, and all you'd need to do is cart a 70" x 35" Musky Toob around in your boat. easy peasy.
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| lambeau - 1/2/2013 4:07 PM
[...]all you'd need to do is cart a 70" x 35" Musky Toob around in your boat. easy peasy.
That part would be easy. But I can see a few challenges when trying to fill it with water and stuff a fish in there, and a few more trying to get the fish out of there without spilling any water. That's what I call good old redneck fun! |
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Location: The Yahara Chain | Why not just weigh the fish? You can weigh it real quick on the water and still release it. A cetified scale would be much easier to store than a tube of water...c'mon who is going to do that.
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| Maybe you could carry the required DNR guys around in the tube so that it doesn't blow out of the boat... |
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Location: Madison, WI | ...
Edited by lambeau 1/2/2013 4:24 PM
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Location: Madison, WI | That part would be easy. But I can see a few challenges when trying to fill it with water and stuff a fish in there, and a few more trying to get the fish out of there without spilling any water. That's what I call good old redneck fun!
a) why would you need to get the muskie out without spilling any water?
2) the point is to sell the thing, why worry about ease of use or accuracy? i figure that with the word "Musky" in the name and a picture of a muskie on the side, it's a sure thing.
Why not just weigh the fish? You can weigh it real quick on the water and still release it. A cetified scale would be much easier to store than a tube of water...c'mon who is going to do that.
exactly. it's a joke...if you want a record, kill the fish and get it certified. otherwise quit worrying about records that will never be validated anyway.
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Location: Kronenwetter, WI | What would be the expected varience in air bladder volume? |
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Location: minocqua, wi. | what is the air-speed velocity of an unladen swallow? |
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Location: The desert | What if you don't have enough water in the 'toob' and the musky bonks its head on the way in?
Perhaps there could be a stamp that people could buy that would allow for one head bonking per year? |
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Location: Yahara River Chain | Here is what you do. Have your muskie toob on a scale, weigh the water, then put the fish in it and weigh it again and subtract the two weights.
Or simpler, just grab the dang fish weight yourself, release the fish. Weigh yourself again and subtract the two weights. You saved $$ not buying the frickin toob.
Why do you guys make it harder on yourselves?
Edited by muskie! nut 1/2/2013 5:00 PM
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Location: minocqua, wi. | go to the top and read big guy
the light bulb will turn on ... or not |
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Location: Black Creek, WI | lambeau - 1/2/2013 4:23 PM ...if you want a record, kill the fish and get it certified. otherwise quit worrying about records that will never be validated anyway. So... forget about records or kill the fish. Now we are getting somewhere. How do we end that? We are men and will forever want to claim that mine is bigger than yours.... If the dreaded volume based FORMULAS using length and girth measurements will not be accepted (for good reason), what are some legitimate alternatives? If we stay with weight.... what are some good methods to weigh fish in the boat? What needs to be done to get an "official" weight for record keeping purposes? There seems to be several fish each season that have RECORD potential. How do we verify these catches without killing the fish? No joke! |
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Location: The desert | I don't care if mine is bigger or smaller. I'm more about the action.
Wait, are we still talking about muskies? |
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| jonnysled - 1/2/2013 4:44 PM
what is the air-speed velocity of an unladen swallow?
in order to maintain air-speed velocity, a swallow needs to beat its wings 43 times every second, right?
Am I right? |
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| Wow it's going to be a long winter.
Back to the original questions:
"are RECORDS established by weight of any value?" Only if said weight can be verified as accurate.
"What good is a State Record (by weight) if there are bigger fish getting caught and released?" The same could be asked about any record - it's only a record if it's been authenticated and recorded. That doesn't mean it's the best, fastest, biggest, etc.
"And... if weight is the metric of choice... doesn't that promote killing a fish and conflict with the poplularity of C&R?"
The short answer is yes. That is until someone comes up with a way to weigh, verify, witness, etc. fish that doesn't require clobbering them and throwing them in the freezer.
A valid set of questions, for sure.
And not to make fun of your post by any means, but... I'm pretty into muskie fishing. But I couldn't tell you what the state record muske is in my state, or who holds it. Nor could I do that for any other state except WI, and that's only because of the dumbf-ckery surrounding the record. |
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Location: minocqua, wi. | i'm going back in the basement ... |
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Location: Black Creek, WI | jonnysled - 1/2/2013 5:55 PM i'm going back in the basement ... Good... now maybe some good discussion will occur on this thread.  |
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Location: The desert | jlong - 1/2/2013 5:27 PM
jonnysled - 1/2/2013 5:55 PM i'm going back in the basement ... Good... now maybe some good discussion will occur on this thread.
Care to wager on that? |
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Location: Warroad, Mn | I've always wondered why some great engineer didn't create a live well big and deep enough so it would hold most fish we catch. Then have a little line on it that says to fill to here wth water. Probably not too important as long at it covers the fish. Then when you put a fish in it there was a little float that went up and down like a gas guage. This would active a chip (computer stuff) that would send a message to a dial on your dash that says this fish weights X number of pounds. No doubt lots of problems with boat and fish movement, but I'll bet someone would sell lots of them! Probably not real accurate, but with refinement it maybe better than you would think, and lots of fun to argue about in the mean time. Doug Johnson
Edited by dougj 1/2/2013 7:42 PM
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Location: Elk River, Minnesota | Hi all,
Been following this with some chuckles here and there on how to get accurate measures and one thing stands in the way of both girth and volume displacement.... Girth changes on some fish as you measure at different parts of the body and as has been stated with using density as a means, it has error in it as well. If we assume uniform density in muskies, that assumes too much (fish in the belly being one of them), how much fat does a fish have, egg mass, etc....way too open for debate.
In my mind there is no better calculation than weight. Now...how to get it done? Use your net...
First, know the weight of your net (wet weight). Then, weigh the fish in the net by putting your scale on hoop of the net right by handle...or if you can lift it high enough, a bolt at the end of the handle. Get the weight, then subtract the weight of the net.
Another option, get an old muskie cradle, attach uniform lengths of rope to each handle end, then do the same calculation. Either way, you will get your weight measurement... The only issue is how accurate is your scale...
If it is for a record, it'll get you close, but it would still probably require a fish to be harvested.
Steve
Edited by VMS 1/2/2013 7:12 PM
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Location: deephaven mn | does weight matter? the same fish say a 58" could vary in weight all season long. if you could catch it prespawn (possible in some states) it would most likely weigh the most, or november after a whitefish feeding binge. if you catch the fish in august
it may weigh 10 pounds less. my point is, it's the same fish, a giant! still a fish of a lifetime! so is it a greater success just because it was caught in the late fall compared to mid summer? |
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Location: minocqua, wi. | dougj - 1/2/2013 6:41 PM
I've always wondered why some great engineer didn't create a live well big and deep enough so it would hold most fish we catch. Then have a little line on it that says to fill to here wth water. Probably not too important as long at it covers the fish. Then when you put a fish in it there was a little float that went up and down like a gas guage. This would active a chip (computer stuff) that would send a message to a dial on your dash that says this fish weights X number of pounds. No doubt lots of problems with boat and fish movement, but I'll bet someone would sell lots of them! Probably not real accurate, but with refinement it maybe better than you would think, and lots of fun to argue about in the mean time. Doug Johnson
jlong doesn't mind density discussions depending on where it comes from doug |
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Location: Warroad, Mn | The density of water is a function of temperature. If this is true for fish I don't know, but could be as they are cold blooded? Still I'll bet that a livewell scale is something that could be done. Still sounds like something a computer could figure out. JLong should be working on this! Doug Johnson |
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| knock-knock-knock ..Penny... knock-knock-knock ..Penny... knock-knock-knock ..Penny ...
now that was a worthwhile thread !! thanks for the laughs Sled, IaJ, Cowboy and Lambeau, that was priceless problem solving !!
Keep it up, I will never buy cable tv just for the only show I like to watch !
( B.B. Theory) |
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| Okay Leonard...
I think what Jason was getting at was that if we are using weight as a barometer for calculating record fish, how do we establish a system/procedure for measuring that weight, and more importantly verifying and documenting that weight, that does not require killing the fish.
Throwing the "who cares?" arguments aside for a moment...
It seems a bit silly to carry a certified and calibrated scale. The simplest way is weigh yourself, pick up the fish, and weigh yourself again. Any digital bathroom scale can do that.
But what is to stop someone from stuffing downrigger balls in their coat pocket to add a few pounds? |
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Location: minocqua, wi. | as long as the down-rigger balls stay in your pockets you're good ...
didn't anyone watch bill nye??
l |
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Location: Eastern Ontario | Apparently Mike Lazarus carries a scale in his boat that has been certified by the IGFA. He recently weighed a 58 pounder for Ed Barbosa. Perhaps Larry Ramsell could explain how this works
Edited by horsehunter 1/3/2013 8:07 AM
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Location: Black Creek, WI | Just like people scoff at how many 49.5" muskies have been "stretched" to be reported as 50 inchers..... how often are girth measurements inflated? Perhaps some of the inflated numbers are not intentional due to lack of knowledge for how to properly take a girth measurement?
So... how many 52 inchers get inflated girths to reach the 40 pound mark?
52 x 23 = 34.4 lbs.
52 x 24 = 37.4 lbs.
52 x 25 = 40.6 lbs.
And... let's use Minnesota as an example. The State Record is no doubt a realistic goal these days based on the length of some of the fish getting released. Is 2 inches a feasible "mistake" when measuring girth? If you catch a 56 incher, I'm sure you will be confident in the length measurement. When you then decide to measure the girth, how confident will you be?
56 x 24 = 40.3 lbs
56 x 26 = 47.3 lbs
56 x 28 = 54.9 lbs and the new MN State Record.
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Location: The Yahara Chain | Where's Ramsell? Live girth vs dead girth is an issue.
Maybe sombody can start a new record keeping organization for volume. We could have modern and historical volume.
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Location: minocqua, wi. | what does a single pt. girth measurement do for accuracy??
completely inaccurate representation in a mass calculation even if it were taken correctly ...
assuming the discussion is about an alternative to certified weight (for you jerome)
Edited by jonnysled 1/3/2013 11:48 AM
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Location: Black Creek, WI | I agree, Bytor. Where are those willing to have a serious discussion? Lots of jokers commented... but seriously... I want to learn more about the girth measurement and how to use it. L x G x G / 800 is a volume equation, right? I'm assuming the 800 is a constant derived from all the conversion factors involved? Has anyone done the math themselves and are willing to explain all the assumptions made? Secondly, any error in the girth measurement is multiplied exponentially... in comparison to an error in the length. If length can vary by up to an inch pending whether you measure with an open tail or pinched tail... how much can the girth measurment vary? How tight should the seamstress tape be pulled? How do you ensure it is "square"? Do you take it while the fish is in the water, on a bump board, or held horizontally for a photo? has anyone experimented with this? |
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Location: Madison, WI | Where are those willing to have a serious discussion? Lots of jokers commented... but seriously... I want to learn more about the girth measurement and how to use it... how much can the girth measurment vary? How tight should the seamstress tape be pulled? How do you ensure it is "square"? Do you take it while the fish is in the water, on a bump board, or held horizontally for a photo? has anyone experimented with this?
the joking was a result of the false assumption included in your original question, jlong. combining records with girth measurements is not realistic because of all the inherent measurement errors such as those you just listed. if you want to know how to make the best possible girth measurement for your own puposes, okay, but let's not suggest that there's any possibility of using them to determine records.
if you're interested in it for your own purposes, i think the thing that matters most is consistency. do it the same way every time and you've got a point of comparison across your own fish. as hard as i might try, i know that consistency from one of my own fish to the next is imperfect, so i don't think it's reasonable to believe it will ever be consistently "right" from person to person.
for myself, i've only girthed a handful of fish. i cut a piece of fishing line and measure the out-of-water girth at point centered between the pectoral fins and pelvic fins (the front two sets on bottom of fish). i try to make sure the line is vertical or at a 90-degree angle to the fish's length. i pull it snug enough to remove any slack line without squeezing the fish. it that right, is that wrong? i dunno, don't care all that much, but i'm consistent. and it gives me a point of reference to at least chuckle when i hear people claim 27" girths...
and of course there are lots of ways to measure fish size: weight, volume, length, girth, head/body ratio, etc. each tells you something, but none of them tell you everything. but since weight is the historic measure for records, i suppose that'll continue to be important. personally, i think it would be great if record-keeping bodies would certify live-weight scales at key access points on fisheries with the potential for record-class fish.
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Location: minocqua, wi. | volume of a symmetrical object
vs. volume of a variable object ...
yah, do the math all the time, not usually on fish.
lambeau = yup |
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Location: minocqua, wi. | the calculation you are showing would use the 800 to average mass density ... the reason it's inaccurate with big fish is that it's derived from a limited volume calculation and no longer represents the shape (volume). if displacement (real volume) is used and tied to a mass-density target you would have a much more accurate number if you chose to want something other than certified weight. |
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| I'll guarantee some of you guys got your books knocked out of your hands a LOT at school.
It's like I said on the other site. Until you go to measuring bone on a dead fish it NEVER will be totally accurate. Any fish that is measured and then released is truly only an estimate of the girth and length because of all the variables. And no, I'm not suggesting we kill any fish.
jlong, to your question about an accurate girth, I have no idea if there's a good answer to it. lambeau did a pretty good job.
I've gotten to the point that I do not score my bucks anymore and rarely measure any of my fish. I shoot what I shoot and I catch what I catch.
StormyK
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Location: Black Creek, WI | There are people out there who are chasing the record. I'm certain there are boats floating around Mille Lacs in November with numbers in mind. If they have the length and girth needed to generate a calculated weight that exceeds the "record"..... it's likley the fish will end up dead. Whether admittedly or under the guise of being deeply hooked. No doubt... some fish will get whacked and fall short of the record. If this scenario exists.... perhaps generating some dialogue on the internet regarding these weight calculators and all the assumptions and errors involved.... we may educate a few people so smart decisions can be made. And dare I say save a fish? Even if we aren't talking about chasing the record or the potential demise of a foish, there are many musky anglers using these calculators today. They might be chasing a goal such as catching a 30 pounder. Are these calculators "tempting" people to exaggerate their measurements to avoid disappointment? Just look at how many critics we have on these boards when someone posts a length and girth measurement with their photos. Considering all of my above comments, I can't find much in past discussions here regarding how to properly take a girth measurement. And I certainly don't see much explaining the formulas. That is what I'm interested in here. We went through the evolution of obtainging decent length measurements around the same time C&R became immensely popular. Floating measuring stic"ks, to cradles, to some really accurate and "good for the fish" bump boards we see today. As girth measruements become more widely used.... why aren't we seeing ways to improve the measurement? If its bunk... then why is it still being used? |
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| It's a lot easier and more accurate to simply buy a very good scale, I spent $100 on one and have weighed a 40 lb dumbell with it and it's off by 2 ounces.
I think I'm fairly accurate girthing fish, have done so on a number of occasions and have weighed them, they came out + or - within 2 lbs of the formula. Some fish have big bellies but don't carry the weight, some are thick head to tail. Lots of variables. It's fairly easy to get an accurate girth on a fish lying on a bumpboard, not sure why some are having a hard time with it?!
Reality is so very few fish in MN are caught that approach/exceed the record.
If you think you want the record, get a scale! |
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Location: Smith Creek | Hi, my name is Flambeauski. If you're anything like me you've always wondered how to measure the countless world record class muskies you release. You've tried measuring them. You've tried weighing them on a bathroom scale. You've even tried photoanalysis. What a mess!
No more!
Now, for the first time ever, you can own the Muskie Volumizer! Simply enter the fish in the Volumizer and it's patented design will tell you the exact volume! No more of your friends calling you liar. No more fish slime on your wife's sewing tape. And if you order now, we'll throw in the Boga Brush, the only product on the market that subdues the fish and cleans their teeth. Just pay the extra processing and handling.
Hurry! Supplies are limited!
Edited by Flambeauski 1/3/2013 1:14 PM
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Location: minocqua, wi. | LxG and a random density number work if you are measuring a 5' 2"x6" ...
as long as you don't mix the maple with the pine |
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Location: Elk River, Minnesota | jlong - 1/3/2013 11:56 AM
I agree, Bytor. Where are those willing to have a serious discussion? Lots of jokers commented... but seriously... I want to learn more about the girth measurement and how to use it. L x G x G / 800 is a volume equation, right? I'm assuming the 800 is a constant derived from all the conversion factors involved? Has anyone done the math themselves and are willing to explain all the assumptions made? Secondly, any error in the girth measurement is multiplied exponentially... in comparison to an error in the length. If length can vary by up to an inch pending whether you measure with an open tail or pinched tail... how much can the girth measurment vary? How tight should the seamstress tape be pulled? How do you ensure it is "square"? Do you take it while the fish is in the water, on a bump board, or held horizontally for a photo? has anyone experimented with this?
Hiya,
Jason you are correct in the equation being a volume measurement as you are basically multiplying 3 dimensions (Length, radius and radius) as it pertains to a cylinder (where the girth acts as circumference). The 800 is basically a constant that was found from using measurements of many many fish with known weights which, when you use the measurements of your fish would put you pretty close to the actual weight of the fish. the 800 itself would include a calculation that converts girth^2 to a radius^2 so it acts like multiplying 3 dimensions (length width and height). then the other portion of the 800 is a constant of variation that converts volume to weight). This equation assumes mass density and has variables in it as well such as the ones mentioned: how do you calculate accurate girth? Where do you calculate girth? How many times do you measure? Average the girths, etc?
No matter what goes on here, there will always be some sort of error involved whether you measure by volume then calculate based upon a given constant or just by the L x G x G/800.
Could it be more accurate if we used a uniform density measurement? Maybe...but that would require accurate measurement for mass and volume of many many fish. Volume being the measurement we would not have for most of those fish. If people would be willing to try something such as measuring volume and weight of their fish caught (all sizes) I would be willing to put the numbers together to see what comes out of it. I'm just a little mathematically challenged...
Steve |
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Location: Hayward, Wisconsin | jlong wrote: “Where are those willing to have a serious discussion? Lots of jokers commented... but seriously... I want to learn more about the girth measurement and how to use it... how much can the girth measurment vary? How tight should the seamstress tape be pulled? How do you ensure it is "square"? Do you take it while the fish is in the water, on a bump board, or held horizontally for a photo? has anyone experimented with this?
LR: First of all Mr. Long, I am “serious”, but perhaps not so much when it comes to measuring the girth of fish intended to be released and then trying to apply a formula to them based on “dead fish”. My mantra is and has been for many years now; “If you don’t weigh it, you shouldn’t say it.” lambeau pretty much summed it up when he said;…”the joking was a result of the false assumption included in your original question, jlong. combining records with girth measurements is not realistic because of all the inherent measurement errors such as those you just listed. if you want to know how to make the best possible girth measurement for your own puposes, okay, but let's not suggest that there's any possibility of using them to determine records.”
lambeau’s comment: “if you're interested in it for your own purposes, i think the thing that matters most is consistency. do it the same way every time and you've got a point of comparison across your own fish. as hard as i might try, i know that consistency from one of my own fish to the next is imperfect, so i don't think it's reasonable to believe it will ever be consistently "right" from person to person. for myself, i've only girthed a handful of fish. i cut a piece of fishing line and measure the out-of-water girth at point centered between the pectoral fins and pelvic fins (the front two sets on bottom of fish). i try to make sure the line is vertical or at a 90-degree angle to the fish's length. i pull it snug enough to remove any slack line without squeezing the fish. it that right, is that wrong? i dunno, don't care all that much, but i'm consistent. and it gives me a point of reference to at least chuckle when i hear people claim 27" girths…”
LR: Can’t say it ever been better said and I agree with his “claim 27” girths” comment! However, lambeau’s comment: “personally, i think it would be great if record-keeping bodies would certify live-weight scales at key access points on fisheries with the potential for record-class fish.” is unrealistic on large water bodies like the St. Lawrence River. Just won’t happen and the issue of transport of large fish would certainly get ugly!!
jlong continued: “There are people out there who are chasing the record. I'm certain there are boats floating around Mille Lacs in November with numbers in mind. If they have the length and girth needed to generate a calculated weight that exceeds the "record"..... it's likley the fish will end up dead. Whether admittedly or under the guise of being deeply hooked. No doubt... some fish will get whacked and fall short of the record. If this scenario exists.... perhaps generating some dialogue on the internet regarding these weight calculators and all the assumptions and errors involved.... we may educate a few people so smart decisions can be made. And dare I say save a fish? Even if we aren't talking about chasing the record or the potential demise of a foish, there are many musky anglers using these calculators today. They might be chasing a goal such as catching a 30 pounder. Are these calculators tempting" people to exaggerate their measurements to avoid disappointment? Just look at how many critics we have on these boards when someone posts a length and girth measurement with their photos…As girth measruements become more widely used".... "why aren't we seeing ways to improve the measurement? If its bunk... then why is it still being used? ”
LR: Again, and if this is indeed the case, then these boats should be carrying certified scales and FORGET about trying to “estimate” a fish’s weight by using the formula! It takes no longer to weigh a muskie than it does to girth it; weighing methods, and several have already been discussed, is what you should be worried about, not “girthing”.
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Location: Black Creek, WI | Recors are being broken. Quite regularly too. In the past 10 years, how many have been "updated"? Michigan's record has been broken several times in the past 2-3 years. And.... I'm only using State and World records as an example here. Especially when there are a fair number of released fish each season with record setting POTENTIAL. So what is the new "standard" for measuring up our catches? Do we need to go to extremes and truly chase the record and kill our catch.... or go the other way and become SOUL fisherman who could care less about the "numbers" since all fish are equals? |
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Location: Black Creek, WI | Lenth measurements have merit since Daily Bag Limits are based on them. Weight measurements have merit as RECORDS are based on them. So... my ORIGINAL question was this, "What is the purpose of taking a GIRTH measurement?" |
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| or buy a scale and learn how to weigh it in the net. Problem solved.
JLong, are you simply trying to figure out what your big one from Vermilion weighed? If so, the weight calculator at the bottom of this site is pretty accurate on MN fish. It will get you close enough anyway. |
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Location: Black Creek, WI | Kerplunk... if I wanted to know the weight... I'd have weighed it. But... I did attempt to take a girth measurement out of curiosity and while doing it, it became obvious that I have virtually NO EXPERIENCE with taking such a measurement. Thus, I"m wondering just what is the value of a girth measurement? And... if they are a necessary evil, how can I improve my next measurement? I see posts titled here "Potential Record" based on a weight calculator that uses Length and girth measurements. When posts occur claiming a new world record.... length and girth measurements are usually presented as evidence. As a result... I really like Ramsell's remark "If you didn't weigh it, don't say it" |
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Location: Smith Creek | I guess if you want a replica made then get the girth. There's no such thing as a state record that was released.
Technically every 35" fish caught is a "potential" state record.
Edited by Flambeauski 1/3/2013 2:37 PM
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| "if you didn't weigh it, don't say it", to some degree sure, but,
I would think most guys that have caught and been in the boat with big fish aren't out there saying their fish weighed 42.97 lbs based off the formula. ie, if it was a solid 55 x 25 I would think most would say it was a low 40 lber. Which it most certainly was. Just like there are guys that don't measure their fish, they've caught enough to not care per say, but when they catch a fish that was high 40 incher, isn't it fair enough to say it was an "upper 40 incher", they didn't measure it, are people going to knock that too? I would hope not.
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Location: Madison, WI | jlong - 1/3/2013 2:12 PM
So... my ORIGINAL question was this, "What is the purpose of taking a GIRTH measurement?"
to estimate weight in the absence of a scale.
just don't expect me swallow your estimation skills. 
Larry Ramsell -
However, lambeau’s comment: “personally, i think it would be great if record-keeping bodies would certify live-weight scales at key access points on fisheries with the potential for record-class fish.” is unrealistic on large water bodies like the St. Lawrence River. Just won’t happen and the issue of transport of large fish would certainly get ugly!!
yes, the issue of transport is one for debate and best avoided when other options are available such as using photographs in tournaments. but if certified weight is the only measure accepted for a record (and in fact your own MDMWRKP insists on it), then i'd like to see fish accepted which are weighed alive and released. if it comes down to live transport versus dead transport of potential record muskies, i'd opt for live transport myself.
many of the recent or "modern" record-class fish have been caught on Great Lakes charter-size boats. there are people fishing these waters who have been installing large revival/transport tanks, there are even some boat brands offering it as a factory option and advertising it specifically for muskies. so i guess i'm not one to scoff at technological advances as being "unrealistic" if serious record-seekers are willing to install such tanks on their boats. encouraging the use of near-shore certified scales seems the easier part of that equation...and a little open-mindedness, of course.
Edited by lambeau 1/3/2013 3:15 PM
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| Holy cannoli .. a muskie toob! |
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Posts: 1938
Location: Black Creek, WI | keplunk - 1/3/2013 2:36 PM "if you didn't weigh it, don't say it", to some degree sure, but, I would think most guys that have caught and been in the boat with big fish aren't out there saying their fish weighed 42.97 lbs based off the formula. ie, if it was a solid 55 x 25 I would think most would say it was a low 40 lber. Which it most certainly was. Just like there are guys that don't measure their fish, they've caught enough to not care per say, but when they catch a fish that was high 40 incher, isn't it fair enough to say it was an "upper 40 incher", they didn't measure it, are people going to knock that too? I would hope not. We are getting too far removed from the catch and kill era... where people had experience of seeing fish that were actually weighed. I doubt many 30 somethings and younger catching legitimate 40 pounders have actually seen a verified one. I'm guilty of holding a fish and declaring it a 40 pounder... yet never actually weighed one myself. Thus, I don't know for sure if I ever really caught one. So... in my opinion the "issue" with the girth measurement is that it is being used to bridge the gap between length and weight. I'm speculating that this is due to the fact that catches approaching "record" status are becoming more "common". In other words.... not measuring an "ordinary" fish is understandable.... but when you catch an "extra" ordinary fish... that's when measurements suddenly become of interest. And... "ordinary" will vary by angler...... |
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Posts: 456
Location: Kansas City BBQ Capitol of the world | On catching that 40#er, wouldn't it be good enough to do your length/girth and see where your approximate is at. If your close, weigh it with your own scale and see where it weighs on your scale. Then later take your 40# dumbbell and weigh that on your scale and then add or subtract if needed. That would be close enough to let you know it was a true 40#er. For records, to bad the old rules apply to CPR. Unless your in the right place at the right time with the right equipment your gonna have to thump it for anyone to believe you and either way, no matter what you do you will get ripped apart.
Ron |
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Posts: 1906
Location: Oconto Falls, WI | To answer your questions from your original post...NO to all the questions. My job requires me to measure the "girth" of paper towel and toilet paper rolls for data collection. I measure thousands of rolls a year, and have been doing it for 10+ years. I have to be careful when measuring with a 4" wide mylar tape, that has zero stretch, not to pull too tight otherwise my data is "off". However all I can do is be as consistent as possible. And this is on a medium that is most often less compressible than a fish would be, and thus should be easier in being repeatable.
If you want record keeping you need to be accurate and repeatable otherwise there will always be people trying to prove something wrong. Even with accurate and repeatable means you still have people trying to prove data wrong as we all have seen the last few years.
You want records you do it with a certified scale. You ask me you cannot rely on length nor girth as accurate means for record keeping of a fish that is not dead.
People really just need to quit worrying about trying to prove someone else wrong, or trying to prove themselves superior. I can say that as at one time I did both.
Edited by CiscoKid 1/3/2013 6:25 PM
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Posts: 8821
| Travis, you say you have to be careful not to compress your medium when measuring girth... Just out of curiousity, when you say your measurements can be "off", what percentage are we talking here?
Now relate that to a muskie, that has a girth of say.... 24". I can't see being off by more than an inch. As long as the tape is flat, the only errors you could make would be pulling it too tight, or not measuring the widest part of the fish, both of which would give you a measurement that is under the actual girth.
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Location: Madison, WI | the only errors you could make would be pulling it too tight, or not measuring the widest part of the fish, both of which would give you a measurement that is under the actual girth
Lol...if the tape is not at an exact right angle to the length of the fish it increases the girth by a fair amount. With wet fish, cold hands, wind and waves moving the boat, lack of practice, and rushing to do it all quickly this is a very easy mistake to make. The formula compounds the error because the girth measurement is squared...add an inch to the girth number in the formula and see what happens. There's nothing small about it!
Girths are unreliable, but they make for good approximations. It's spitting in the wind to try and make them something they can't be.
My bet is few people are measuring girths. Rather they believe they caught a fish that weighed a certain amount so they just claim whatever girth gets them there in the formula.
Edited by lambeau 1/3/2013 8:42 PM
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| lambeau - 1/3/2013 8:34 PM
the only errors you could make would be pulling it too tight, or not measuring the widest part of the fish, both of which would give you a measurement that is under the actual girth
Lol...if the tape is not at an exact right angle to the length of the fish it increases the girth by a fair amount. With wet fish, cold hands, wind and waves moving the boat, lack of practice, and rushing to do it all quickly this is a very easy mistake to make. The formula compounds the error because the girth measurement is squared...add an inch to the girth number in the formula and see what happens. There's nothing small about it!
Girths are unreliable, but they make for good approximations. It's spitting in the wind to try and make them something they can't be.
My bet is few people are measuring girths. Rather they believe they caught a fish that weighed a certain amount so they just claim whatever girth gets them there in the formula.
Nice how you conveniently left out the first part of my post - AS LONG AS THE TAPE IS FLAT. |
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| That thing is so totally cool!! I want one!!  |
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| Well I really have no background here so pardon the ignorance, but do they only judge a record on length or length and girth, or length, girth, and weight or including volume? And who does all the measuring? Are there standard tools that are used for all possible record fish? (doubtful) Are there witnesses? (sounds like a murder…) Do people kill them to make sure there aren't any mistakes or just because they can or to get the ACTUAL fish stuffed…?
I know there has been, is still, quite a bit of controversy over records and these are a lot of questions, but I'm curious. |
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Location: Madison, WI | Nice how you conveniently left out the first part of my post - AS LONG AS THE TAPE IS FLAT.
yeah...something that is "flat" is not necessarily "at a right angle."
http://www.youtube.com/watch?v=OHVjs4aobqs
Edited by lambeau 1/4/2013 7:52 AM
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Location: Contrarian Island | i've girthed maybe 15 fish total....it's not hard... and imo it's hard to mess up by over 1/2"
lay the fish on the bump board w the tape down prior, pull tape tight and find the fattest point (again w tape tight)
the value of it to me is just to know how fat it was ... it puts the weight in perspective as the ones we have girthed and weighed (w very accurate scale) came out VERY close to the weight calculator on this site...so, to me, it is nice to know a big one I caught was about 45-46 lbs as in the heat of the moment w all the excitement and adrenaline flowing we spaced and forgot we had the scale with us... d'oh!
most guys aren't girthing fish unless they are Big and FAT...ie, i'm not about to girth a summer 52 incher w an avg girth...what's the point...but a FAT 54 in the fall i sure might want to just to know approximately what it weighed if i didn't want to bother w getting the scale out...one thing it did prove to me is there are a lot less 40 lbers being caught than guys realize....
takes a lot of fish to hit 40 lbs and most would thing a fairly fat 54 hits 40...well, it doesn't...
Edited by BNelson 1/4/2013 8:16 AM
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Posts: 1938
Location: Black Creek, WI | Brad, can you share more info on the scale you use? If you feel its accurate, do you feel there would be no need to measure girth... or heck... even length? Also, what do you feel is "fairly" fat for a 54 incher... considering there are photos of a 54x30 on Musky Hunter right now boasting a weight of 58 lbs.... as verified by a scale. Also, I found SOME explanation of the weight calculator formulas here: http://www.huntfishsport.com/web.aspx?cmd=muskieWeightCalculator |
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Location: Oconto Falls, WI | esoxaddict - 1/3/2013 7:29 PM
Travis, you say you have to be careful not to compress your medium when measuring girth... Just out of curiousity, when you say your measurements can be "off", what percentage are we talking here?
Now relate that to a muskie, that has a girth of say.... 24". I can't see being off by more than an inch. As long as the tape is flat, the only errors you could make would be pulling it too tight, or not measuring the widest part of the fish, both of which would give you a measurement that is under the actual girth.
For record keeping, as this thread was meant to be directed towards, you would want to minimize any kind of error percentage. For me I can see upwards of 2% variance, so that *could* equate to ½” variance in this discussion. However keep in mind I am using a 4” wide tape. The wider the tape is the more accurate your measurement should be. I am also dealing with something that does not move, something I can take my time to ensure I am measuring it correctly, something that is not slippery, something that is uniform in diameter, etc…
Taking a half inch variance you could see the following:
55” x 24” fish = 39.60# per Muskyhunter formula
55” x 24.5” fish = 41.27# per Muskyhunter formula
On a 60” fish
60” x 28” = 58.80#
60” x 28.5” = 60.92#
Is a 1.67# variance acceptable when it comes down to records? I say no way considering the records are kept down to the nearest ounce. So as the questions were asked here “Can it be done with any accuracy and repeatability? Enough to be used for establishing "records"?” I say no. Should you use girth for YOUR OWN record keeping? I say sure why not.
Too many variables can affect measuring girth for an accurate and repeatable measurement for record keeping. Not much in the way of variables affecting you when you weigh a fish, and thus why it is the BEST way for record keeping.
Getting an accurate girth of a fish is not easy to do!
Edited by CiscoKid 1/4/2013 8:27 AM
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Location: minocqua, wi. | why not:
thermal expansion and contraction of your measuring device ...
take a piece of metal/plastic ... put standard lengths in an oven, put the same standard length in the freezer. one is shorter, the other longer yet they are the same size.
same fish measured on a 90deg. day and measured on the ice are different ... measurement is always relative. pesky standard conditions always get in the way when you want to be "exact" ... |
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Posts: 1938
Location: Black Creek, WI | This site has 5 formulas to choose from. How do you choose which one to use? http://www.esoxhunter.com/weightform.php Is there a generally accepted formula used by the Muskiy Community? |
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Location: Contrarian Island | I guess i will disagree w you Travis...measuring girth is easy imo.... laying big fish on a bump board, most of the time they don't move...the fish being slippery actually helps imo moving the tape up or down the fish..have you girthed many ? your post would make it seem like you haven't...?
Jason, as far as my scale it's a Salter Brecknell Electro Samson 99 lb scale...
as stated using length x girth for record keeping when the fish was not weighed and released is not realistic in the slightest...fish are proportioned so many ways that without weighing a fish you're only estimating...which for record keeping isn't the right way to do it.... for fun, the formula gets you pretty close..that's about it.
Edited by BNelson 1/4/2013 8:54 AM
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Location: Oconto Falls, WI | jlong - 1/4/2013 8:32 AM
This site has 5 formulas to choose from. How do you choose which one to use? http://www.esoxhunter.com/weightform.php Is there a generally accepted formula used by the Muskiy Community?
J those questions are good reasons on why you cannot use girth and length measurements for record keeping. First the “community” would have to universally adopt one formula. Then you would have to have a “certified” measuring tape used for Length and Girth. Then you would have to have a “certified” process in how you measure both. Then you would have to have someone verify the measurements that were taken.
Sled is there much thermal expansion of a fiberglass reinforced tape in 90° temps versus 20° temps?
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Location: Oconto Falls, WI | BNelson - 1/4/2013 8:51 AM
I guess i will disagree w you Travis...measuring girth is easy imo.... laying big fish on a bump board, most of the time they don't move...the fish being slippery actually helps imo moving the tape up or down the fish..have you girthed many ? your post would make it seem like you haven't...?
Brad I have girthed a handful, and all in the water. Sure the more I would measure the more comfortable I would feel, but I would always have doubt it is accurate. However it was for my own benefit so I don’t fret it. The fact of you bringing this up is another good reason Length and Girth plugged into a formula is not a good way for record keeping. It shouldn’t matter if you are measuring your first fish or your 5,000th fish in terms of how easy it is to get an accurate measurement. |
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Location: Contrarian Island | makes sense...in the water is definitely harder than a fish on a bump board... |
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Location: minocqua, wi. | this article goes into way too much detail for measuring the coefficient of thermal expansion itself. i'll try to dig to see where it comes down to temp. vs expansion for typical materials.
http://www.vishaypg.com/docs/11063/tn5131tn.pdf
like you Travis and Jason i work in the world where circumferencial to linear measurement to precise standards is critical especially when working with various materials. printing, converting and especially extrusion (heat) in the round and application on the flat all day everyday with varying densities and modulous materials.
if trying to get to exact standards that's why i would continually argue an L times single pt. W using a density standard and the same as what's resonated in the responses including the one from BNelson.
using displacement is the only way to accurately consider a mass density given in a calculation and be remotely accurate (for true record-keeping) and why using a scale is most important for really, really big fish confirming that mine is bigger than yours arguments.
Edited by jonnysled 1/4/2013 9:30 AM
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Location: Hayward, Wisconsin | And there you have it, from Sled. If you want to say it, weigh it...pretty simple and foolproof with a Certified scale. No "estimates", just fact. |
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| CiscoKid - 1/4/2013 8:26 AM
esoxaddict - 1/3/2013 7:29 PM
Travis, you say you have to be careful not to compress your medium when measuring girth... Just out of curiousity, when you say your measurements can be "off", what percentage are we talking here?
Now relate that to a muskie, that has a girth of say.... 24". I can't see being off by more than an inch. As long as the tape is flat, the only errors you could make would be pulling it too tight, or not measuring the widest part of the fish, both of which would give you a measurement that is under the actual girth.
For record keeping, as this thread was meant to be directed towards, you would want to minimize any kind of error percentage. For me I can see upwards of 2% variance, so that *could* equate to ½” variance in this discussion. However keep in mind I am using a 4” wide tape. The wider the tape is the more accurate your measurement should be. I am also dealing with something that does not move, something I can take my time to ensure I am measuring it correctly, something that is not slippery, something that is uniform in diameter, etc…
Taking a half inch variance you could see the following:
55” x 24” fish = 39.60# per Muskyhunter formula
55” x 24.5” fish = 41.27# per Muskyhunter formula
On a 60” fish
60” x 28” = 58.80#
60” x 28.5” = 60.92#
Is a 1.67# variance acceptable when it comes down to records? I say no way considering the records are kept down to the nearest ounce. So as the questions were asked here “Can it be done with any accuracy and repeatability? Enough to be used for establishing "records"?” I say no. Should you use girth for YOUR OWN record keeping? I say sure why not.
Too many variables can affect measuring girth for an accurate and repeatable measurement for record keeping. Not much in the way of variables affecting you when you weigh a fish, and thus why it is the BEST way for record keeping.
Getting an accurate girth of a fish is not easy to do!
So you're talking about a variance of 1.67# for a 60" fish. I'd agree that girth measurements are not an accurate way to determine records, but it looks to me like the formulas will get you pretty #*^@ close to the actual weight. |
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Location: Madison, WI | Larry Ramsell - 1/4/2013 11:00 AM
And there you have it, from Sled. If you want to say it, weigh it...pretty simple and foolproof with a Certified scale. No "estimates", just fact.
Should a fish weighed alive on a certified scale (with appropriate witnesses etc.), and then released alive be considered for record purposes?
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Location: Rhinelander, Wisconsin | No. A Live release division is not available through any of the WR Keeping organizations.
Should a Live release division be offered? Plenty of reasons why it would be quite difficult to establish and maintain, but with enough money, it may be possible for an organization to offer.
Key words:
Enough money. |
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| Take a check, Steve? |
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Location: Hayward, Wisconsin | And what happens lambeau, to that one pound (or more) trolling lead(s) that was/were dropped into the fishes stomach before filiming began??? Where is the MDMWRP Representative or do we just rely on their/your 10 "friends"?
And, where are all these "lakeside" certified scales? I'd certainly like to build a list so anglers would be able to find where to go. Even now it is difficult to find a certified scale for kept fish. Nice thoughts though. |
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| best way to stress and kill a musky is to keep one in the livewell for hours |
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Posts: 8821
| Guest - 1/4/2013 7:08 PM
best way to stress and kill a musky is to keep one in the livewell for hours
Almost as effective as bonking it because you think you may have a state record. |
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Location: deephaven mn | state record? how many state records of any species are caught by anglers that are less than avid? i am a guessing that luck has a large part to do with alot of state records, and then there is the added weight possibility. let it go and smile possible state record has got to be good enough! i think? |
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Location: deephaven mn | ok
Edited by kap 1/4/2013 10:14 PM
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| I can only speak for myself, but... I have no idea what the state records are where I fish. I've caught one. Long ago. Black crappie that would have been the state record at the time. I ate it. It was good. |
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