01-30-2019, 08:22 PM
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Senior Member
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Join Date: Nov 2016
Location: Crossville
Posts: 359
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Quote:
Originally Posted by bfish
I don't know the complete history of FL strain in Chickamauga but do have some intel.
As the largemouth fishery on Chick was crashing in the mid '80's, due to increases in flow (although many mistakenly blame TVA spraying milfoil). A study by a PhD theorized that FL strain would survive (not necessary thrive) below a diagonal line from just north of Birmingham and Chattanooga but well south of Knoxville.
From my understand, Anders Myhr (RIP, then Region III chief), presented the idea to a local bass club to sponsor stocking of the FL strain to boost the population. Genetics were not a concern back then. I believe it was 300-500 fingerlings shipped from FL per year for the first several years.
Later on TN was able to overwinter FL brood fish and the stocking rates increased, however managers were not seeing any results. So around 2000 Kevin Hoffman performed some work and published his findings in 2002. Yes the FL stocking genes were moving into the general populations, but were still mostly confined to the original stocking embayments. Since then, with continual stocking and natural wandering, the genes have spread and you see some F1 hybrids being caught.
Now here comes the rub…..
F1 hybrids will eventually spawn with other F1, and you start to loose the hybrid vigor the F1 shows. FL strain have a less tolerant range of spawning temperatures than native and are less fecund (i.e. produce fewer eggs) than native. This can lead to missing years of spawning. Also F2 will not have the same growth rates as the pure and F1. Over time the population average size will decrease. Even if the entire lake was all F1 (with no native), the population numbers would be lessen, as pure FL and F1 hybrids don't support as dense populations as native. The further away you go from natural habitat of the FL strain the more pronounced negatives become.
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Very interesting, Thank you
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