|SREL Reprint #0945|
Microgeographic Genetic Organization of Populations of
Largemouth Bass and Two Other Species in a Reservoir
K. Kennedy, Michael L. Kennedy and Michael H. Smith
Biochemical variation encoded by three loci was
assessed for largemouth bass collected over two years from eight sites evenly
distributed around a reservoir receiving thermal effluent. Body conditions,
which was positively correlated with body-fat level, was examined as an
indicator of differential environments. Thermal
and temporal effects on body conditions were not seen for the genetic
characteristics. Sexual differences
were not observed in body condition and were minimal genetically.
Samples of bass from different sites exhibited homogeneity of allelic
frequencies, while previously reported data from similar sites indicated
significant heterogeneity in bluegill and mosquitofish.
The degree of spatial genetic heterogeneity seemed related to body size
– highest heterogeneity in the smallest species (mosquitofish), lowest in the
largest species (largemouth bass). Allele
frequencies for the samples were negatively correlated over short distances in
each of the three species, this pattern could be explained be explained by
strong selection in a patchy environment or by a tendency for differential
dispersal of fish of various genotypes.
SREL Reprint #0945
Kennedy, P.K., M.L. Kennedy, and M.H. Smith. 1985.
Microgeographic genetic organization of populations of largemouth bass and
two other species in a reservoir. Copeia 1985:118-125.