Relative weight chart for bluegills.

[Bruce Condello]

Relative weight, sometimes abbreviated as simply "Wr", is a reference to how much a bluegill should weigh for a particular length.

If you look at all bluegill in a particular region of the country, the fish that would be at the 75th percentile, or bigger than three out of four fish is given the designation of Wr 100.

Therefore, if you catch a fish that is 10% heavier than the 75th percentile bluegill for your region, your fish will be given a designation of Wr 110.

Quite honestly, if you're catching bluegill with Wr's in the 90's, these are pretty healthy fish because they're still bigger than average, which would be about the 50th percentile.

I'd like to see a lot of www.bigbluegill.com members familiarize themselves with this particular system. It is helpful for biologists in determining what's going on in a body of water to know the relative weights. High relative weights generally mean that the overall population of a particular species has abundant forage, and probably a better potential to achieve high weights. If you want BIG BLUEGILL, you want them to have high relative weights or Wr's throughout their lifespan.

Here's the chart, and I apologize to those of you who are "metrically challenged".

And now....Thanks to Big Bluegill member Jesse Schertzer, we have an English Units table for to play with. Somebody out there go catch a bluegill, and get a weight and length, and we'll use this chart to show a Wr value!

Thanks, Jesse!

[Bruce Condello]

....OK, I hope the previous chart makes sense. If anybody knows how to create something that's more "table-like", be my guest. ;)

[Bruce Condello]

Big Bluegill member Bill Cody provided me with the following Wr table addition for those of us lucky enough to catch a bluegill that's too big for the original Wr chart.



STANDARD WEIGHT OF LARGE BLUEGILL

0.0” 0.25” 0.5” 0.75”
9” 9.9oz 10.9oz 11.8oz 13.0oz
10” 14.1oz 15.4oz 1 lb 0.6oz 1 lb 1.9oz
11” 1 lb 3.6oz 1 lb 4.8oz 1 lb 6.4oz 1 lb 8.0oz
12” 1 lb 9.7oz 1 lb 11.7oz 1 lb 13.6oz 1 lb 15.5oz
13” 2 lb 1.6oz 2 lb 3.8oz 2 lb 6.1oz 2 lb 8.5oz

[Zig]

I'll certainly start documenting my data from local waters on the site now. (I thought I was the only fish nerd that sliced bone and pulled scales for enhanced viewing)

Ken- there is a ton of info on the net for using scales to age fish, but I have to warn you: it's not something you grasp on the first scale you look at.
I've gotten conflicting readings from multiple scales from the same fish.
I started looking at cut otoliths along with scales to get a positive age determination, as I had too many discrepencies by using scales alone when I first started. The problem with using them is 100% mortality rates.

[Ken G]

"As for aging data, I collect scales, then I press them and view under a microscope, but since I know that's not practical for most people I'd be interesting in tagging information that anybody may have."

Bruce,

Do you possibly know:

Is there is a tutorial anywhere for using scales to provide age information?

How accurate are scales for determining age?

Will it work for both bass and bluegill?

If we pull a scale off a healthy bluegill or bass that is released, could it cause health issues for the fish?

Thanks,
Ken

[Bruce Condello]

I am definitely on board when it comes to documenting weight vs. length data on larger bluegill. I can probably sample several dozen fish in the 10 plus inch range.

As for aging data, I collect scales, then I press them and view under a microscope, but since I know that's not practical for most people I'd be interesting in tagging information that anybody may have.

I'll try to contact Mr. Cody.

[Ken G]

Zig,

Thanks for the additional chart. It would be interesting to know how they came up with those numbers.

I think Bruce, and maybe Bill Cody, may have a lot more data on this. I think it may also have a lot to do with geographical latitude.

Based on what I've seen, I think I'd mostly agree with bluegill Wr up to about 9.5 inches. From about 9.5 inches and above, my experience is that bluegill put on a lot more weight for every quarter inch of length than shown in the chart.

I would hope we could get a number of people to keep records for bluegill above 9 inches next season -- keeping length in quarter inch increments, weight in ounces, and sex.

As my fish get above about 9.5 inches, they seem to start getting much thicker than longer.

I just wish I had a reliable way of estimating or measuring age. Maybe we need to all start tagging our larger fish. Does anyone know of something that is simple and inexpensive that amateurs could use?

[David Merical]

I'm green with envy, Ken! I've caught some giant 9.5" bluegills in the past couple years [or so they seem to me ;o) ], but I haven't caught a true 10" bluegill since 1989 or 1990! I know they're around...I just haven't crossed paths with them yet! Soon....soon!

[Zig]

Ken - this link may have the numbers you are looking for:

A second Wr chart

I'm slightly confused about the differences between the two(2) charts now within this thread.
If I run my above listed numbers through the ACES chart they breakdown like this:
8", 6.0ozs = 94 Wr (relative weight)
8", 4.9ozs = 77 Wr
8.25", 6.1ozs. = 95 Wr
8.5", 6.5ozs. = 1.02 Wr
9", 8.2ozs. = 85 Wr

Either my math is flawed, or there's a discrepancy in the "standards" somewhere.
It's interesting to note the ACES charting uses much broader numbers then the source Bruce posted - makes me wonder how much of it has been "calculated" past a given point. (?)

[Bruce Condello]

I'm in on that.

Ken, if I could transport myself to any pond in the world to fish for an hour tonight, it would definitely be yours! :)

[Ken G]

It is interesting that both charts stop where I really want to start. I'm not very interested in knowing the Wr of my bluegill below 10 inches. As long as they are healthy, that is all that counts. Most male and female below about 9 inches become dinner unless they have spectacular features. Most fat and healthy males and females above 9 inches go back in. Mostly, I would like to make comparisons with others growing large bluegill. For my personal records, I figure that a bluegill at 10-inches, weighing 1 lbs., equals a Wr of 1.0 at non-spawning time. At 10.25 inches, they should weigh 1.25 lbs. At 10.5 inches they should weigh 1.5 lbs, and at 11 inches, they should weigh close to 2 lbs. My fish come real close to these numbers. This evening I caught and released one 10-inch male, two 10.25 inch (a male and a female), and kept one 10.5 inch male (deeply hooked). I brought my scale down to the dock this evening. My fish were real close to the numbers I listed above.

In recent years, including this year, I've only recorded quantities by size (kept or released). Next season I plan to record length, sex, and weight of my bluegill. Maybe several of us can compare notes this time next year and come up with a quasi- accurate Wr table.

Ken