Man, that's a hard one to answer. You would typically think that they are in the counties that have high sheep and goat populations, but they are controlled pretty heavily in those areas so they wouldn't thrive as much as they could if left alone. It is even hit or miss around Midland. I can drive 50 miles in one direction and maybe see one cat per year, while I can drive 50 miles the other direction and see a ton. I would think that any county that has good cover and water and that isn't hit too hard by the ADC men would have higher populations of cats. I also think that large cattle ranches that border large sheep ranches are bound to have a high number of cats. The cattle ranchers typically aren't worried about cats, while the sheep and goat men are and take action to prevent the cats from killing. Still hard to say, though. I know there are good numbers of cats in most of the counties I hunt in Texas, but there are even some counties where I can find a good population in one area, and none in the other....all within the same county. It's probably all dependent on habitat and whether they are being controlled or not.
Take care and God Bless,
Rusty