The Aoudad have been moving in slowly from up around the Palo Duro Canyon area. They were stocked back in the 40's about the same time they stocked the Big Bend area. Post, Fluvvana and other area's north have a substantial population and had some on a ranch I used to lease nth of I-20 and east of Coahoma. These are the only wild ones I know of that are south of I-20 in this county, guess they couldn't resist the mountains.
Yes a Weatherby does kill them deader.