Killing nannies doesn't do a population any favors. Compound that, and you can quickly make a population unsustainable IMO, either through hunting or predation. All goat tags should be billy only.
Thanks for posting the maps
@Randy11 I couldn't remember the entire range, just recalled that the majority of the goats lived around GNP or in the NW corner. I didn't realize there was native herds in the Pioneers and Root. I wonder what those populations were like, if they were robust, or just spill over/remnant populations?
There is talk of climate change being an issue, but we've been transitioning out of the last ice age since goats arrived, at some point their habitat and ideal conditions peaked in their southern range, and they had no where to go, but decline. If you overlay rainfall depths to native goat ranges, you'll see that most of the areas they were transplanted are quite dry comparatively as well.
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