# I had an encounter with a cougar (mountain lion). What does the recurrence time look like?

I had an encounter with a cougar recently. I was walking down a muddy old forest service road when approximately 15-20 meters behind me a deer burst out of the brush with a cougar chasing it close behind. The cougar gave up the chase on the deer but watched it jump away (instead of turning around to see what I was doing). Meanwhile I am backing away around the corner to get out of the situation. I didn't see either the cougar or the deer again.

What I'm curious about that a biology perspective might be able to answer is how frequently cougars return to a hunting area. My qualitative understanding is that they have very large ranges, so under a quite few stochastic process models I would expect them to return to the same hectare relatively infrequently. But I don't have a quantitative understanding of this.

Has someone worked out some empirical distribution (conditional or marginal) on the return-time of cougars to a given hunting location?

## Update

A cougar was spotted by someone else approximately 15 kilometres away within 2 weeks of my encounter.

This observation is a Casual observation on iNaturalist: ID 110726469

• I'm guessing the variance on something like this is too great to be useful, beyond what you could roughly estimate by range. But perhaps someone will be able to answer anyways. Jun 22, 2021 at 1:37
• Yes, the variance could be very large. I also find that ecological models are not adequately validated, and rely too heavily on either linear preasymptotic AIC or asymptotic AIC to be realistic. But, I will take what I can get. Jun 22, 2021 at 3:39
• An obvious (at least to me) problem with doing such an analysis is that it assumes that all locations within the range are equally favorable. But deer (a preferred prey of the cougar) have their preferred trails & feeding areas, so a successful cougar is likely to learn to hunt where the prey is, and not where it's not likely to be. Jun 22, 2021 at 6:03
• After a bit of googling: home range of a cougar is between 30 and 1000 km². If we assumed that it is a circle, the bigger number corresponds to a diamater of just above 60 kilometers, which is a two-three days walk for a human in a forest. So it is actually not that big. Jun 22, 2021 at 9:24
• @RogerVadim Thanks for looking that up, and for the back-of-the-envelope calculation. It raises interesting questions about the geometric properties of the home ranges of animals. Jun 22, 2021 at 14:41