Photo of the San Juans by borga used under a Creative Commons license.
Rick Bass, The Lost Grizzlies: A Search for Survivors in the Wilderness of Colorado (Houghton Mifflin, 1995).
Generally understood to have been extirpated from their historic range throughout the Lower 48 States save for isolated populations around Yellowstone and Glacier National Parks, grizzly bears have nonetheless been rumored to still hold out in the San Juan Mountains of southwestern Colorado. Along with bear expert Doug Peacock — a larger-than-life character better known as the model for Hayduke in Edward Abbey’s The Monkey Wrench Gang — and biologist Dennis Sizemore, Bass hiked into the San Juans to search for grizzlies.
Here is Google Book Search. The Mississippi Writers Project has biographical information about Bass. Thomas McNamee reviewed it in The New York Times. Mark Mardon reviewed it in Sierra. Here’s a capsule review from Entertainment Weekly. In Sandpoint Magazine, Dennis Nicholls writes about grizzlies. Bass wrote this piece about the bears for Time in 2002. Here’s a 2006 report of a grizzly sighting in the San Juans.