Pond Boss Forums INTRO Questions & Observations Alright.....who else can't catch their fish?

I know TP&W genetically tests all the fish that they get called to get for their "Sharelunker" program. I wonder how that plays out percentage wise between the pure Florida strain and the F1's (and possibly pure Northern strain)??

If I remember correctly, most ShareALunker fish had Fla genes but were not pure Fla LMB. Don't recall any pure Northern strain, though there may have been a few.

IMHO I think both of the ideas are correct (and incorrect) in part. Breeds, Lines, and Varieties are all examples of artificially selecting for a predictable standard for life like dogs, fish, and tomatoes. These standards have highly concentrated genes that produce a great degree of variety of traits within a species (for example chihauhuas and great danes). Usually when inbred lines of different standards are bred together, the F1 offspring produced are fairly consistent in terms of their traits. But the FX generations do show a high degree of variability. If the F1 was very desirable, often efforts are undertaken to select for the F1 traits and produce an inbred variety that consistently produces offspring that are like the F1s. This can only be done through artificial selection as nature will itself go the path that favors those traits that contribute most to reproductive success. If the breeder is very good at identifying the desired traits he can usually produce a variety, breed, or line with traits that are consistent with the F1 generation in about 7 to 9 generations.

I think most people over anticipate the level and consistency of selection from recreational fisheries suppliers than they would expect from tomato seed supplier, for example. I think the most pertinent traits are shaped by natural selection factors in what seem to be regionally superior traits. Here regionally superior means that the trait contributes to reproductive success over the long haul in the waters these fish have evolved. In a recreational pond, the traits that win are those that favor reproductive success and after 7 generations the genes will reflect what contributed most to reproductive success. If aggressiveness, then we will see that trait (as we do in the North). Faster growth and slower metabolism seem to be important to survival and reproductive success in the South. I think each pond is its own laboratory and one very important environmental influence is the human predator contribution of fishing and culling/harvest. There is only one way to remove this influence on traits of a population of the adult fish. One would need to eliminate the dependence on natural reproduction for trophy path recruits.

Here is a start to an archive on the topic - I am still looking for more.



Which Bass Type - F-1 Tigers or Native - Pond Boss Forum
https://forums.pondboss.com/ubbthre...ntegrade+zone&Search=true#Post496578

Must read: PB article on Genetics & Catchability! - Pond Boss Forum
https://forums.pondboss.com/ubbthre...ntegrade+zone&Search=true#Post475742

f1 bass offspring - Pond Boss Forum – Bob has a comment
https://forums.pondboss.com/ubbthre...ntegrade+zone&Search=true#Post463289

Lone Star Legacy Bass Breeders 2016 - Pond Boss Forum – Bob has a comment
https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=447815&page=1

To help all understand that there is a natural intergrade zone where there is little evidence of F-1 , F-X outbreeding depression.


Cold intolerance is the known reason. Many studies confirm this. There are plus and minuses and corresponding reasons for each LMB stocking approach. There is no one "I am right" plan. See info below map for others view.

There is little to no proof that outbreeding depression applies to Fla/North crosses whether they are F-1 , 2 or FXs (all referenced as integrades) in there natural integrade zone .


Status of Subspecies as of 2011 subject to change:
Florida Largemouth Bass and the Northern Largemouth Bass were once considered to be subspecies. Many state fisheries agencies still consider them to be subspecies and treat them as such, often stocking �Florida strain largemouth� on top of the native Largemouth Bass stocks. Although the American Fisheries Society (AFS) also officially still recognizes them as subspecies, biologists specializing in the field are calling for them to be separated into two distinct species: Florida Bass and Largemouth Bass. This is based off genetic studies that suggest that the genetic variation between Florida Bass and Largemouth Bass . A natural intergrade zone occurs where the two species� ranges meet and overlap in the deep southeast. Artificial intergrade zones exist where state agencies have stocked Florida Bass over Largemouth Bass for decades.





http://sepond.com/fish-stocking/largemouth-bass --- Southeastern Pond Management approach


Here is American Sport Fish�s approach.

Florida bass in the southern latitudes grow faster after age two, and live longer than Northern bass. They also have the potential of reaching larger sizes. These are record-breakers. However, they are less tolerant of cold temperatures, and they can be harder to catch. As they grow older, they learn to ignore artificial bait. Pond owners often complain about not being able to catch larger Florida bass, except on live bait. Nevertheless, their size and long lifespan make them excellent additions to many ponds.

Through more than 15 years of genetic selection, American Sport Fish has developed a very aggressive strain of northern bass called the Gorilla bass. Aggressive feeding behavior is an inheritable trait, and each generation of bass has been selected for its aggressive behavior. These fish are strong feeders and respond well to artificial baits even when they become older. They are more tolerant of colder water than the Florida bass..Adult Gorilla bass are often added to lakes that are home to a majority of Florida bass, to increase the angler's catch rate and to introduce their aggressive feeding genetics to Florida bass populations.

Created by our team of scientists, the Tiger Bass� has been specially bred for aggressiveness and fast growth. In well-managed lakes, Tiger Bass� have consistently gained more than two pounds per year. Biologists refer to this fish as a true F-1, because it is a cross between two pure subspecies of bass: a special strain of aggressive Northern Bass (which we call Gorilla Bass) and a pure strain of Florida Bass that comes from proven trophies (females from 13 to 16 pounds). American Sport Fish is the only hatchery licensed to produce and sell the Tiger Bass�
The world record bass, which weighed 22 pounds and 4 ounces, came from southern Georgia and is thought to be a northern/ Florida intergrade. Our Tiger Bass� have already gained weights of 15 pounds in eight years. We expect them to break state records in the next several years.


F1 LMB vs Florida strain LMB, pros and cons??? - Pond Boss Forum
https://forums.pondboss.com/ubbthre...ntegrade+zone&Search=true#Post441639


Tiger Bass ( F1) - Pond Boss Forum
https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=274647&page=1

F1 LMB and Outbreeding Depression - Pond Boss Forum many good biologists on this one Wes Neal , D Willis , Overton , Grimes and others – lots of good stuff in this one
https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=184554&page=1

Wes notes --
wneal
Lunker
W
Joined: Sep 2009
Posts: 10
United States
Hey Eric, and thanks for the "warm" welcome all. I agree completely with Eric that inbreeding is much more of a concern. However, I want to argue one point...

You cannot compare intergrade bass (have both strain's alleles) that are naturally produced and adapted over 1000s of years with Fx generation hybrids produced through man-made causes in a small pond. The natural intergrades have had much time to select for the genes from both sides that best fit their environment. Thus, the "bad" combinations have been weeded out. No such selective pressures occur in ponds in the time frames we are discussing, so the bad combinations will persist and their inferior traits may become evident in only a few generation. That is the risk of outbreeding depression.


I agree that stocking from multiple sources may be a good idea. However, Dave Davidson's comment about the impurity of pure strain fish is a major concern. Despite what some people claim, the only accurate way to tell a Florida bass from a northern bass is genetically, so it is real easy to accidentally contaminate a pure strain population. We plan to test fish from a few hatcheries this spring - I will report on what we find.

No one has really looked at the time needed between gene pool refreshments. I would guess that every 5-10 years would be good, and is certainly better than never.


F1 outbreeding depression? - Pond Boss Forum
https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=141071&page=1

Do I need some better genes? - Pond Boss Forum
https://forums.pondboss.com/ubbthre...ntegrade+zone&Search=true#Post129974

Thus, although our results provide no evidence of a genetic basis for variation in functional

morphology, the observed phenotypic plasticity represents an important mechanism

that can mould a fish�s morphology to the resource base of a lake.


intermixing lmb strains... - Pond Boss Forum
https://forums.pondboss.com/ubbthre...ntegrade+zone&Search=true#Post114857

PB may/june09 Science & the cutting edge.... - Pond Boss Forum
https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=204888&page=1

This speaks to what I was saying above. An intergrade population which has undergone natural selection over many generations is very different from the F1 combination of two isolated populations. Each population has genetics concentrated in traits important to their waters and the fish that survive to reproduce are reflections of these dominate genes. Each population is in essence an inbred line that has been naturally selected for its particular environment.

When inbred lines are crossed, many dominate traits are expressed in the offspring from both lines. The next generation allows more variation to one side or the other. I don't consider this depression in terms of the quality of the genetic pool, only that the individuals have a broader spectrum of traits expressed in the Fx generations. In truth, the F1s are more genetically diverse than offspring of the pure strains. Intergrading between connected bodies of water is probably important to genetic diversity in general allowing the larger populations to share genes over time scales important to evolution.


Here I think that Wes may be underestimating the speed of selection. In addition to fishing harvest, the natural selection acting on fish populations is rather intense. Only a minute fraction of swim up fry will successfully reproduce. The genetics favorable to reproductive success in this environment will dominate the adults that are recruited. LMB live for 9+ years. The individuals initially stocked (but not culled) will dominate the catch of large fish during this time frame, when they have passed, natural selection and fishing mortality will be what has selected the generations that take over.

Good hatcheries (that first produced F-1s) are run by fisheries biologists and they through years of selection for good traits in both Flas and Northerns have accounted for this issue. They are well aware of the issue and constantly select from their stock to produce the best product. That is why your source for fish is important.

I would be interested in any info from someone who has experienced outbreeding depression in a pond stocked only with quality F-1s. There have been many thousands of such stockings and no suggestion of a problem to my knowledge. There is significant selection inside the pond and millions of different possible genetic combinations upon which evolution works.

Bob Lusk
Editor, Pond Boss Magazine
Lunker

Joined: Apr 2002
Posts: 3,192
Likes: 4
Whitesboro, Texas
F1 bass cannot have true F1 offspring. They can have F2 offspring or Fx (unknown) offspring. They cannot breed back to the genetics of the original parents, either. They can only provide the genetics they have, which is a mix of both parents.

Fish genetics is much more complicated than others, for several reasons. With deer, you have a known buck, known doe, one to three offspring...and they don't eat each other. You can provide the best habitat, great food, etc, and see the results in a couple of years.

With bass, a female may have 30,000 eggs, which might hatch, some might not. Then, of those which hatch, only a percentage has the right genetic mix of good growth, aggressive nature...whatever they need. If some percentage of those fish survive long enough, you can grow big fish. But, under water, it's a 'fish eat fish' world. We can't control survival rates or judge the fish as they grow so we can protect the best of the best youngsters before they get eaten. So, it becomes an environmental situation with luck.

I completely agree with these comments above Eric. The competitive environment in the pond prevents bad genetics from growing up to spread inferior genes. What makes it to reproductive age has great genetics, or I suppose might have been very lucky, but I do not believe in luck.

Perhaps there really is vigor resulting from the combination of Northerns and Florida. If so, even if F2 progeny is highly variable, the ones that survive to reproductive age are reasonably argued to be the ones with relatively greater vigor. So perhaps mother nature performs the selection of those progeny that are most like the parents (F1s)