A new report by a national conservation group says national parks across the U.S., including ones in the Rockies, face obstacles to protecting their natural and cultural resources due to underfunding and understaffing.

The report released today by the National Parks Conservation Association gives the national park system only a "fair" grade. The assessment, called "The State of Our National Parks: A Resources Index," was based on studies since 2000 of 54 parks -- including Colorado's Rocky Mountain National Park.

The senior vice president of the Washington, D.C.-based non profit, Ron Tipton, says he's confident the report is a good representation of the 391-unit national park system.

He says it's the first report to give a clear summary of the condition of the national parks' resources.