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| From the
1999 Southern Division of the American Fisheries Society Midyear Meeting held in
Chattanooga, Tennessee. |
Stocking Advanced Fingerling and Subadult
Largemouth Bass into Florida Lakes
Wes Porak, Steve Crawford and Dennis Renfro Florida
Game and Fresh Water Fish Commission P.O. Box 1903 Eustis, Florida 32727 Voice
352-357-6631 FAX 352-357-6635 E-Mail porakw@gfc.state.fl.us
Keywords: largemouth bass; stock enhancement;
survival; relative weights (Wr); liver disease
Florida Game and Fresh Water Fish Commission biologists
have feed trained and raised largemouth bass Micropterus salmoides on artificial
feeds for stock enhancement studies. The objectives of this study were to determine
survival rates and percent contribution of stocked largemouth bass in populations that
were stocked. Ten lakes stocked with advanced fingerling (6-13 cm TL) and/or subadult
(11-36 cm TL) largemouth bass have been studied since 1994. Stocking rates have varied
from 16 bass/ha to 290 bass/ha. Stocked largemouth bass were either microwire-tagged or
fin-clipped to differentiate them from wild fish. Stocked largemouth bass appeared to be
highly vulnerable to angling in Lake Lawne (63 ha) where a creel survey indicated angler
catch rates were 1.26 bass/h for 3 months following stocking. Stocked largemouth bass were
less piscivorus than wild fish (within the same size range) during the first month after
stocking on two stocked lakes where food habit studies were conducted. Mean relative
weights (Wrs) of stocked largemouth bass were significantly lower than wild
bass within the same size range. Fifty-four stocked and 36 wild largemouth bass were
sampled from 7 different stocked lakes to do liver histologies. Twenty percent of the
stocked largemouth bass and 0% of the wild largemouth bass had diseased livers. Survival
of stocked largemouth bass ranged from <1% to 34% in 8 study lakes where survival was
estimated after 1 year, and survival in 6 of the 8 lakes was <3%. Percent contribution
of stocked largemouth bass in electrofishing samples ranged from 3% to 14% after 1 year.
We will discuss how factors such as predation, feeding efficiency and disease may have
affected survival of hatchery-raised largemouth bass in stocked lakes, and the future
direction of this program.
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