Declaration Dr. Thomas H. Pringle - Buffalo Field Campaign

and Lamar Valley, in comparison to the higher values between these groups and Hayden
Valley (2005 and 2006) suggest that genetic exchange between Mirror Plateau and Lamar
Valley bison may occur more frequently than with central range animals (Table 3-2).
These data suggest a possible stepping-stone pattern of gene flow within YNP,
whereby genetic exchange is more likely to occur between adjacent subpopulations (or
breeding groups) than geographically distant ones. Therefore, because adjacent
subpopulations are more similar, genetic drift will have more of an effect and result in
greater differentiation among breeding groups in this model of gene flow. This observed
pattern of genetic differentiation is in contrast to the conclusions of Meagher et al. (2002)
who suggested that bison that previously ranged between Mirror Plateau and Pelican
Valley may have assimilated into the Hayden Valley bison after the mid to late 80’s.
Their conclusions were based on observations of large congregations of bison within
Hayden Valley during the rut, from air surveys conducted during 1983 to 2001. However,
the possible pattern of gene flow among YNP breeding groups, as suggested by the
observed haplotype frequencies, does appear to match closely with historic bison travel
routes described by Meagher (Taper et al. 2000; Gates et al. 2005). Therefore, the current
YNP bison population may be carrying on historical movement patterns of their
ancestors, which in turn has contributed to the pattern of genetic differentiation we
observed with mtDNA haplotypes.
Significant genetic differentiation between GTNP and YNP was found
previously by Halbert (2003) using 49 microsatellite loci (FST = 0.102). The FST (0.191)
we found for mtDNA was only twice that estimated from Halbert’s microsatellite data.
This difference is lower than would be expected, however, since mtDNA generally
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