In this April 4, 2017, photo released by the National Park Service shows P-55, a young male Mountain lion that roams the western end of the Santa Monica Mountains in California.

National Park Service via AP

A house cat was eaten by a mountain lion trapped in a Boulder home. Another was struck by a car when it tried to dash across I-70 near Glenwood Springs.

Encounters like these are increasingly common, but why?  David Baron, an author and journalist who has studied how wild animals and expanding suburbs intersect, said that these run-ins are something that will continue to happen, but not for the reason you might think.

New research from CSU and Colorado Parks & Wildlife studied the behavior of mountain lions over a 10-year period. While suburban sprawl does encroach on open spaces where big cats and other wildlife live, Baron said that neither proximity nor hunger are the driving causes. Rather, it's convenience.

Because mountain lions are lone predators, their survival depends on the path of least resistance when it comes to hunting. A house cat or pet dog is much easier prey than a wild deer or fox.

As for why big cats are traveling to dense suburban areas in search of food, it's simply because that's where their natural prey is gravitating to as well.

Baron used the city of Boulder as an example where the mix of wild and urban can cause conflict. Development in the backyard of open spaces causes an overlap of habitats that attracts all kinds of wildlife, he said. Bears, deer, foxes and raccoon can all be drawn into town, lured by the promise of food.

Raccoons happen to be one of mountain lions' favorite meals. But if a lion is tracking a raccoon and happens across the family dog alone in the yard—well, we know the outcome.

Baron’s advice? Treat all of Colorado like mountain lion country, and educate yourself on how to live safely around them. Traveling in groups, keeping pets indoors and removing items such as bird feeders and fountains that attract all kind of wildlife can minimize encounters and keep everyone safe