Bass growth

[Rampow7155]

I have been tagging and tracking largemouth bass in a 15 acre pond for one year now.  I have only caught a few tagged fish but here are two of the most recent.  

1) Tagged 4-15-2016

15" and 2lbs 00oz

Recaught 10-20-2016

17.75" and 3lbs 05oz

2) Tagged 5-31-2016

20.25" and 4lbs 13oz

Recaught 10-20-2016

21" and 5lbs 14oz

Pond has threadfin and gizzard shad, stocked 5,000 3"-4" coppernose bluegill in March 2016. 

Largest LMB to date is 25" and 8lbs 8oz 

My question is, what are poor/normal/exceptional growth rates? 

In north MS

 

[Crayon_Eater]

Sounds like you didn't drain them before you weighed them.  Rookie mistake

[Scott F]

Depends on what part of the country you are in. Contact your local DNR for normal growth rates in your area.

[Rampow7155]

Caught 2 fish I had tagged earlier in the year and started reading about bass growth, curious if these numbers are low, average, or above average?

5-31-16    4lbs 13oz-20.25"                  4-16-16      2lbs-15"

Today        5lbs 14oz-21"                       Today        3lbs 5oz-17.75"

I'm in north MS

[frogflogger]

sounds like really good growth to me

[Mainebass1984]

59 minutes ago, Rampow7155 said:

Caught 2 fish I had tagged earlier in the year and started reading about bass growth, curious if these numbers are low, average, or above average?

5-31-16    4lbs 13oz-20.25"                  4-16-16      2lbs-15"

Today        5lbs 14oz-21"                       Today        3lbs 5oz-17.75"

I'm in north MS

Seems to be good growth to me. The fish you caught on 5-31-16, did it look like it had recently spawned ? A pound of growth in less then a year is above average to in my opinion. Were these fish in good condition when you caught them ? Pre spawn ? Post spawn ? The length gain seems to be average for both fish. Smaller fish tend to grow quicker until they reach a specific size or age and then the growth rate slows down significantly.

Tagging fish is illegal in some states. Be careful.

[Rampow7155]

5-31 fish was definitely post spawn, both were in good condition

[Oufb90]

I had a game warden here in northern Oklahoma tell me an average largemouth grows a little less than one pound per year here. I'm sure it's different in different areas. 

[Mainebass1984]

Largemouth bass in the northern extent of their range have limited growth opportunity. A pair of mature bass spawn when temperatures are around 58-63 degrees. The largemouth spawn typically happens in the first 2 weeks of June on most bodies of water in northern New England. Specific water bodies may vary slightly because of there size and depth. Once the eggs have been laid it takes up to 10 days or them to hatch depending on the daily water temperature (DTUs). These young of the year fish grow rapidly and attain on average 4 inches of length by the end of the growing season which typically ends the beginning of November or the end of October. It has been noted in several studies that if the yoy bass do not attain 4 inches in length their chances to survive the winter are near 0. The period from hatch out until they reach one year of age is the most critical time for survivability. At year 2 they are on average 8 inches in length. The 3rd year they are 12 inches. At this point growth rates typically slow slightly to on average 3 inches per year until they reach maturity at 18-20 inches. Once they reach 20 inches in length growth rates slow considerably. They may not gain an inch a year. At this time much more weight is gained by girth then by length.

Growth rates vary from water to water do to habitat, forage, population, DTUs, species competition. Growth rate can vary from year to year as well.

If you catch a 20 inch northern largemouth it is not a young fish. It has taken several years to attain that length.

[Paul Roberts]

That's excellent growth.

In the wild -in most unmanaged waters- here in the north, bass don't have the consistent opportunity for such growth. In my ponds the YOY bass (age 0) go into winter at 2 to 3 inches in length, double that over second summer, then gain about 1-1/2" to 2" per yr after. An 18er is on average about 8yrs old. This is, apparently, not out of the ordinary.

[Mainebass1984]

1 hour ago, Paul Roberts said:

That's excellent growth.

In the wild -in most unmanaged waters- here in the north, bass don't have the consistent opportunity for such growth. In my ponds the YOY bass (age 0) go into winter at 2 to 3 inches in length, double that over second summer, then gain about 1-1/2" to 2" per yr after. An 18er is on average about 8yrs old. This is, apparently, not out of the ordinary.

Wow. That is terribly slow growth. I've never heard of such growth. Are you sampling these fish yourself ?

[WRB]

Keep in mind LMB over 20" length are females a very high percentage of population. Growth differs between the sex of LMB. Growth rate of 1 pound a year after the adult female reaches 3 1/2 to 4 lbs for about 4 years in most states then slows or stops for the majority of the LMB population. Very small % will grow beyond 8 lbs.

Post spawn bass must first gain back the weight lost during the spawn cycle. The 20" female could have lost 1/2 lb from egg laying and not eating for 2 to 3 weeks.

Tom

[Mainebass1984]

1 hour ago, WRB said:

Keep in mind LMB over 20" length are females a very high percentage of population. Growth differs between the sex of LMB. Growth rate of 1 pound a year after the adult female reaches 3 1/2 to 4 lbs for about 4 years in most states then slows or stops for the majority of the LMB population. Very small % will grow beyond 8 lbs.

Post spawn bass must first gain back the weight lost during the spawn cycle. The 20" female could have lost 1/2 lb from egg laying and not eating for 2 to 3 weeks.

Tom

Ovarian weight is usually 20 % of body weight at the time of spawning.

Stating the bass grow 1 pound per year in most states is a very broad generalization of growth rates.

 

[Paul Roberts]

On 10/22/2016 at 10:06 AM, Mainebass1984 said:

Wow. That is terribly slow growth. I've never heard of such growth. Are you sampling these fish yourself ?

No, I'm not direct aging. This info comes from data collected by state agencies throughout the north, from conversations with managers here, and from my own observations following year classes and some recaptures.

Fish, as I know you know, are extremely variable in growth potential. (Stating this for the wider audience). A given bass could gain anything from 0 to 3lbs/yr depending on growth season and sheer amount of food it can catch. Most bass, in most waters, do not gain such high rates simply bc they cannot catch enough food. Waters with high growth rates, much less sustained high growth rates, are rare in the wild. Of course those are the waters that attract anglers. People who successfully manage private trophy bass fisheries come to realize how much forage is required to grow bass, and how carefully population size-structure must be managed. This stuff is simply rare in the wild.

[Goose52]

OUTSTANDING GROWTH !

I am nearing the end of my second season of tagging LMB in three of my local lakes (38, 16, and 11 acres). I have tagged 691 bass so far and have 298 recaptures of those bass. Of those 298 recaptures, NONE have generated any of the oft-quoted growth metrics (e.g., x inches/year, x pounds/year). I get pretty exited when I have, say, a 14" bass grow an inch in a year. I have bass that I measured at 260 mm 16 months ago that are now only 270/275 mm (in other words - a 10" bass still being around 10" 16 months later).

So my lakes represent the flip-side of your lake - mine are very infertile, with generally poor forage, with many skinny bass having very low "relative weights". OTOH, I do have some very healthy, plump bass having relative weights at 100% or over that apparently are able to out-compete most of the other bass for available forage.

Here are my average relative weights for inch classes from 10" to 22":

10"	79.1%
11"	81.1%
12"	77.5%
13"	75.6%
14"	73.8%
15"	73.5%
16"	75.2%
17"	77.9%
18"	76.9%
19"	77.1%
20"	76.8%
21"	81.3%
22"	77.0%

These results have REALLY made me appreciate it when I catch a 4, 5, or 6 pound bass in my water - they are scarce, and have taken a LONG time to achieve those weights.

 

Anyway - it sounds like your investment in forage (shad and bluegill) is paying BIG dividends !

 

[Paul Roberts]

19 hours ago, Goose52 said:

OUTSTANDING GROWTH !

I am nearing the end of my second season of tagging LMB in three of my local lakes (38, 16, and 11 acres). I have tagged 691 bass so far and have 298 recaptures of those bass. Of those 298 recaptures, NONE have generated any of the oft-quoted growth metrics (e.g., x inches/year, x pounds/year). I get pretty exited when I have, say, a 14" bass grow an inch in a year. I have bass that I measured at 260 mm 16 months ago that are now only 270/275 mm (in other words - a 10" bass still being around 10" 16 months later).

So my lakes represent the flip-side of your lake - mine are very infertile, with generally poor forage, with many skinny bass having very low "relative weights". OTOH, I do have some very healthy, plump bass having relative weights at 100% or over that apparently are able to out-compete most of the other bass for available forage.

Here are my average relative weights for inch classes from 10" to 22":

10"	79.1%
11"	81.1%
12"	77.5%
13"	75.6%
14"	73.8%
15"	73.5%
16"	75.2%
17"	77.9%
18"	76.9%
19"	77.1%
20"	76.8%
21"	81.3%
22"	77.0%

These results have REALLY made me appreciate it when I catch a 4, 5, or 6 pound bass in my water - they are scarce, and have taken a LONG time to achieve those weights.

 

Anyway - it sounds like your investment in forage (shad and bluegill) is paying BIG dividends !

 

Goose52, Very cool what you're doing. What are relative weights? How calculated? Thanks.

[Goose52]

53 minutes ago, Paul Roberts said:

Goose52, Very cool what you're doing. What are relative weights? How calculated? Thanks.

Hi Paul.  I am going to paste an explanation of relative weight that I just Googled.  I use a largemouth bass relative weight chart provided by the biologist that my community has on retainer to help manage our lakes. I believe that the RW formula for LMB has been standardized and that my table is an industry standard. You can Google and find some "calculators" that take the work out of determining the RW for a specific fish. In my case, I have over 2,200 recorded weights of bass from 10" up to 26". I only have enough weights to be somewhat statistically valid up to 22" so that is the upper end of my RW calculations. My Excel spreadsheet automatically calculates the average weight of each inch-class. I then take that average weight and use the standard weight on the RW table to calculate the RW percentage. Anyway, I only catch and re-catch bass, keep records, and crunch numbers on this tagging program. Our biologist that I work with is the expert on this stuff...I'm only the "field force" ! 

Relative weight is an index used by fisheries biologists to determine if a fish is in good condition, fat, or thin. It is calculated by dividing the weight of a fish by the expected weight for a fish of the same species at the same length growing rapidly with plenty of food. In the scientific and management literature, this index is usually multiplied by 100 to put it in whole units or percentages. A relative weight below 80 is very thin, around 90 is average, and greater than 100 is considered fat. In a well-managed fishing pond, the fish would typically have relative weights around 90. 

So, from the above explanation, you can see that my LMB, with all inch-classes averaging between 73 to 81 % of RW, are considered VERY thin.  Turns out I have a very good excuse/reason for why I catch so many small/light fish !

[WRB]

Most fishery biologist measure bass differently than bass anglers do. The biologist usually measure length from tip of closed lower jaw to the base of the tail, thus  eleminating the tail.

Bass anglers measure bass from tip of closed lower jaw to the end of the tail at the longest measurement, this leads to subjective lengths. The formula I came up with back in the 70's measures bass from the tip of the closed jaw to the center of the tail end, same as IGFA, but slightly different than most bass anglers using measurement boards today. I  Didn't know that biologist measure to the base of the tail back in the 70's.

My Formula: length X length X girth / 1200 = weight in lbs. This formulas needs a accurate set of measurements, both length and girth, not a realitive average weight. RW using my formula would be; length X length X .75  length* / 1200 = RW weight in lbs.

* 75% of length is the average body girth for the majority of bass.

Very interesting growth study Goose, well done!

Tom

[Goose52]

18 minutes ago, WRB said:

Most fishery biologist measure bass differently than bass anglers do. The biologist usually measure length from tip of closed lower jaw to the base of the tail, thus  eleminating the tail.

Bass anglers measure bass from tip of closed lower jaw to the end of the tail at the longest measurement, this leads to subjective lengths. The formula I came up with back in the 70's measures bass from the tip of the closed jaw to the center of the tail end, same as IGFA, but slightly different than most bass anglers using measurement boards today. I  Didn't know that biologist measure to the base of the tail back in the 70's.

My Formula: length X length X girth / 1200 = weight in lbs. This formulas needs a accurate set of measurements, both length and girth, not a realitive average weight. RW using my formula would be; length X length X .75  length* / 1200 = RW weight in lbs.

* 75% of length is the average body girth for the majority of bass.

Very interesting growth study Goose, well done!

Tom

Thanks Tom - this is fun stuff and worth the effort required for all the record keeping. BUT, as I say, I'm only the "guy in the field" catching, tagging, and measuring fish - the biologist is the guru on what all this means...

BTW - the relative weight tables are based on the "pinched tail" measuring method and that's what I use for all my length measures (and that's what our TN state wildlife agency uses as well). For the tagging program, I measure to 1mm in length but due to the location of the mm measurements on my bump board I have standardized on using the upper lobe of the tail/caudal fin as my measuring location. In some cases, the lower lobe might be longer but since we are measuring growth, not absolute length, standardizing on one lobe or the other works just as well.

[Paul Roberts]

Thanks, Goose52. 

I found this pdf, and it too uses the pinched tail on measurements:

http://fisheries.tamu.edu/files/2013/09/Relative-Weight-An-Easy-to-Measure-Index-of-Fish-Condition.pdf

The standard weights/length in this table appear a bit high to me. But then again they are to represent fish "growing rapidly with plenty of food", which in my experience is relatively rare in "the wild", if we consider all bass waters, not just the really good ones.

Tom, I measure similar to the way you do. Many angler's interest is to determine legal size, or "bragging" size: stretching as much length out of a fish as possible: usually squeezed tail and pulled out lower jaw. Measuring "standard" like a biologist (closed mouth to end of body -"caudal peduncle") eliminates the most anomalies, like long or eroded tails, or protruding lower jaws. But it doesn't help an angler looking for a "legal" or "tournament legal" fish. I took to measuring top jaw to open tail, which is pretty consistent and is a reasonable compromise. I suppose if I switched to measuring to the lower jaw -makes sense- I could add a 1/4" or so to each bass I've caught. Kinda like that idea.