We see them all the time here; there are two nearby dens for cubs that I know of, so, yes, lots of deer carcasses around.
Our house rules: nobody runs around when the light levels are low, e.g. dawn or dusk, and always take a dog out with you if you are going out between dusk and dawn. We have German shepherds with high protection instincts. Our outside lights are motion activated, so they come on as we exit the house. We pay attention to other animals, just in case. More often than not, our horses or cows will see the mountain lions (cougars/panthers) first. Then again, our animals are quite non-reactive to their presence, which suggests to me that the mountain lions come through often, and don't bother the animals. Our animals are quite reactive to pigs, and I have seen the horse hunt, surround, and drive pigs out of the pasture.
Know your environment; cougars like to be safe, so they tend to be in brush, in trees, or on rooftops. When we lived in town, animal control followed up on a young girl reporting one on the neighbor's roof, and tracks were found there. Subsequent game cameras showed that the mountain lions were moving along stream beds through town, and then leaping onto roofs to go house to house on roof tops. It was said to explain some of the local small dog and cat losses.
Locally, mountain lions have been observed to jump forty feet horizontally, and eighteen plus feet vertically. Around here, they are exclusive hunters of deer, except for a few months when young adults are scouting for new territory and can run short of deer. A neighbor has had cattle on an area with a den for more than fifty years and has never lost a calf to a mountain lion. (Ok, anecdotal.)
Candidly, I worry much more about feral pigs. Statistically, cougars aren't much of a risk.
To review recent (2008–2015) United States mortality data from deaths caused by nonvenomous and venomous animals and compare with historical data.The …
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All the best,
Peter