Baron's book lays out the tale of the gradual return of cougars to the wildland-urban interface in the Colorado Front Range region, describing the beasts' increasing boldness around humans, their snatching of domestic pets, and finally incidents of predation on human beings; and also the changed social context that made this phenomenon possible, and the various human and institutional reactions to it, some complacent, some shrill, some prescient.
I had a curiously mixed reaction to the book. On the one hand, it's interesting raw material, and Baron creates an entertaining narrative. On the other hand there are some irritating things about the book, particularly when he strives to put it all into a larger social context. Whether you will like this book or not really depends on how tolerant you are of the axes which Baron chooses to grind.
Baron shapes his narrative as if the "lion problem" emanated from Boulder and was caused by the Boulder cultural context. It didn't, and it wasn't. The first fatal lion attack occurred in Idaho Springs, near I-70, and closer to the Denver suburb of Lakewood than to Boulder; the second occurred in Rocky Mtn National Park, where one might as well blame the gateway town of Estes Park, or National Park service policies; the first of the non-fatal attacks he relates occurred in the foothills southwest of Denver; only the second (non-fatal attack) could reasonably be said to have occurred "in Boulder", or more exactly a couple of miles out of town up one of the canyons that debouches in boulder. Why does he turn this account of Front Range lions into an account of "Boulder lions"? Partly, one imagines because Boulder contained a few prescient people who saw the phenomenon building and documented it. But also because Boulder contains some of the more florid cultural elements which enable him to turn this into a narrative of naïve eloi nature-worshippers being eaten by lions. It's in fact a much wider phenomenon and doesn't really have a whole lot to do with Boulder animal rights activists.
It's pretty clear that reduced, or eliminated hunting pressure on lions, bears meso-predators (e.g., coyotes, bobcats, raccoons) is one part of the story, and that changing cultural attitudes about nature have helped to bring about that reduction in hunting or trapping pressure. But economic forces are also part of the explanation. When ranching was a principal industry across much of the mountain west and the rockies foothills, mountain lions were shot on sight as a matter of course, because they killed calves. Now that working ranches are disappearing from much of the mountain west, and have effectively disappeared from the Front Range, the economic incentive to kill the beasts has declined accordingly, quite independently of whether they are "protected" or not. And as for fur trapping, how many people make money trapping bobcats or beavers anymore? Such grueling occupations pay next to nothing; financially speaking one would be better off flipping burgers.
It's also clear that new exurban living patterns--ultra-low-density far-flung suburbs--are part of the explanation, since they put people and houses into good wildlife habitat, and also offer trophic resources such as succulent non-native plants, garbage, and domestic pets, which are not present in real wildlands, and which wild animals learn to take advantage of. Baron says some accurate things about this new exurban living pattern--that it is part of a "grand unintended experiment", that people are moving out to more natural environments as the beasts are simultaneously moving into humanized environments, and that problems will result. But in sophistical style he uses these problems (e.g., being attacked by lions) as a sufficient reason to declare that the idea of wilderness is a myth, that people are affecting everything, and a preservationist leave-it-alone approach is untenable, etc, etc. He brings up the old hoary conservation-vs-preservation debate dating back to Gifford Pinchot vs John Muir.
He also suggests that nature lovers approve of this new residence pattern and its attendant human-nature mixing. "America is becoming one vast ecotone where civilization and nature intermingle. To some this suggests a utopian state of affairs. Peregrine falcons nest atop skyscrapers..." The thing is, no conservationist or naturalist I know, however much they enjoy peregrines nesting on skyscrapers, has anything but dislike for the exurban living pattern. It is wildland-destroying, gluttonous of resources, and unsustainable. If Baron payed any attention to e.g., voting patterns, demography, or the distribution of mega-churches, he would understand that low-density exurbs are by many measures culturally conservative spaces, as much a latter day "white flight" as they are an expression of affinity for nature. No doubt many of those "eco-tards" living in Boulder understand that perfectly well, which is why they live in the city of Boulder at urban densities rather than up some canyon with a half-mile driveway on a 15-acre private kingdom and a giant sport ute.
Baron also busily sets up, and knocks down preservationist straw men who advocate for leaving "pristine" nature alone in all circumstances, when in fact, he argues,there is no "pristine" nature left, and so everything needs to be "managed". Once again, I have no idea who Baron is talking about here. Every conservationist I know understands that human beings are affecting every square inch of the planet these days. Anyone who knows anything about conservation biology understands that "pristine" spaces are not large enough, and not connected enough, and not representative enough of all earth's biomes, to be able to preserve earth's biodiversity. One has to pay attention to more human-affected parts of the landscape as well. It is also pretty clear to every intelligent naturalist and conservationist that in the lower 48 there is no escape from some form of management for large wide-ranging carnivores like wolverines, grizzly bears, and yes, cougars, and that managing humans and human residence patterns is also necessary to minimize conflicts. The remaining wild areas simply aren't big enough, or connected enough, and the potential for conflict with humans is too great. Even the 4.5-million acre greater Yellowstone ecosystem is a bit small to sustain grizzly bears indefinitely without genetic interchange with other populations, which might need to be done artificially. Fishers were recently returned to Olympic National Park via an artifical reintroduction, after an absence of some decades. There was nothing controversial about it. Everybody understood that fishers were very unlikely to recolonize the area on their own from remaining source populations in Montana and Idaho.
Exceptions of this sort notwithstanding, there in fact are still vast areas of the mountain west for which the best long-term "management" strategy is to leave them alone. Nature is resilient, and can recover from disturbance of human or natural origin in interesting and complex ways. Conversely it is absolutely incorrect to think that the traditional resource extraction agenda is dead or defeated on our public lands. Federal land management agencies and their allies (with the honorable exception of the National Park Service) have learned to disguise retrograde resource-extraction agendas under the guise of "restoration", that is all.
On the specific subject of cougars, I personally think Baron makes a bit too much of the notion that cougars are doing this stuff only because humans, for the first time ever, have stopped their "aversive conditioning", i.e., hunting and killing the beasts. Cougars are at the best of times idiosyncratic and unpredictable, and my guess is that they have been sneaking up on people, and following them, and occasionally preying on them, for as long as humans and cougars have shared this continent. I have seen cougars on the ground only four times. By far the spookiest of these encounters--the cougar approached me stealthily in the dark to within about five meters, where I noticed it by its eyeshine-- was in an area of Baja California where ranchers still shoot cougars on sight, and where cougars have next to no opportunity to get habituated to human beings.