While 8-16,000 Black Bears still call Colorado home(despite likely having to start enduring a Spring hunt in addition to the Fall kill), the last verified Grizzly Bear was killed in 1979, a Sow whose cubs escaped the hunters rifle............Nonetheless, the state has declared the Griz extinct since that date.............It took roughly 100 years after settlers poured into Colorado in the 1850's for the "Big Bear" to be eliminated from the landscape...............While the occasional supposed sighting of Griz in the San Juan Mtns continues to take place periodically, we are going to have to transplant Griz back into those mountains if in fact a viable population is ever to walk those lands again

 http://blogs.denverpost.com/library/2012/10/07/grizzlies-vanished-colorado-spurred-trappers-ranchers-federal-government/4136/. 

1904 Griz thought to be the last in Colorado shot and killed