Pond Boss Forums STOCKING A NEW POND Types of fish to choose Tennessee reservoir strain smallmouth?

I've heard references to a "TN reservoir" strain of smallmouth?

Is this a special strain of smallmouth and do hatcheries raise it?

Thanks

That depends on how far down the gene strand you go. Different studies show historic differences for SMB over geologic time.
My guess is there is local adaptation in SMB in the lower Tenn river system but they are not a strain or subspecies. I would guess that some of those fish were caught locally and are used by small producers.

Keep in mind that there were no reservoirs on the Tenn River system until about 100 years ago. That is like one second on the genetic time clock for family Centrarchidae .

This should help on the time periods involved. From The Cutting Edge - No. 8

Here is the basic story. Millions of years ago peninsular Florida was, like it is today, connected to the mainland. Bluegill were present all over the eastern US. Sea level rose and peninsular Florida was cut off by the sea from the mainland creating two separate populations. Bluegill on both the mainland and on the peninsula continued to evolve separately each influenced by local conditions with a divergence time of roughly 2.3 million years. After a few million years of this separate path sea level fell and the two land masses were connected again. However the two bluegill sub-species were now a little different genetically. The rivers were connected and the two subspecies migrated and integrated in a zone along the deep southeast where the two sub-species mixed. If this sounds familiar it should – it’s the same story as the Florida Largemouth Bass and the Northern Largemouth Bass where the divergence time between Northern (M. salmoides) and Florida (M. floridanus) bass is approximately 2.8 million years.

The only different "strain" for smallmouth I'm aware of is the strain native to the Ozark/Ouachita mountains (that I'm sure would not be desirable for ponds).

I would think the TN "strain" would be VERY similar to most all smallmouth from middle america.

I would think any effect would just be a selection of large fish's genetics for the most part.

I agree but note that different literature calls different SMB niches or locations implying different strains. I think the reason for the question is that the world record SMB and many similar large SMB are from a region of central Tenn/north MS - Pickwick lake/Tenn River.

Only reason I mention it is fish departments reference said fish in stocking lakes for "trophy" smallmouth bass

Only real difference is that the Tennessee Smallmouth can hold its liquor better than some northern strains, such as those from Pennsylvania.

Or maybe I have it confused with the Northern Small Fathead. Sheesh, been working too hard lately.

You are on point Yolk -- nice assessment !!!!! --

Think about how much improvement Bruce Condello and Cecil Baird have done to their BG over just a few generations of selective breeding. I suspect SMB over a hundred years in the wild could adapt some to new conditions. If you really start to look at wild fish populations, you will see huge variances in populations, even from adjacent river systems. I can often tell the difference between Potomac River RBS and Rappahannock River RBS by their coloration. They each have distinct coloration. Those rivers are within a few miles of each other but are isolated enough to show distinction. Is it enough to create a subspecies or even a strain, likely not. Natural selection is constantly working and fish are constantly evolving. I suspect if someone worked on it for a couple decades, they could breed a strain of SMB that was more adapted to pond life and could reproduce in ponds that didn't have so much rocky structure in them...

This may help.

Phenotypic plasticity is the ability of an organism to change its phenotype in response to changes in the environment. Fundamental to the way in which organisms cope with environmental variation, phenotypic plasticity encompasses all types of environmentally induced changes (e.g. morphological, physiological, behavioral, phenological) that may or may not be permanent throughout an individual’s lifespan. The term was originally used to describe developmental effects on morphological characters, but is now more broadly used to describe all phenotypic responses to environmental change, such as acclimation or acclimatization, as well as learning.

Evolution of phenotypic plasticity
Plasticity is usually thought to be an evolutionary adaptation to environmental variation that is reasonably predictable and occurs within the lifespan of an individual organism, as it allows individuals to ‘fit’ their phenotype to different environments. If the optimal phenotype in a given environment changes with environmental conditions, then the ability of individuals to express different traits should be advantageous and thus selected for. Hence, phenotypic plasticity can evolve if Darwinian fitness is increased by changing phenotype . However, the fitness benefits of plasticity can be limited by the energetic costs of plastic responses (e.g. synthesizing new proteins, adjusting expression ratio of isozyme variants, maintaining sensory machinery to detect changes) as well as the predictability and reliability of environmental cues (see Beneficial acclimation hypothesis).