It does not have a national inventory of internal threats that integrates information it already has, and many of its individual units do not have a readily available database on the extent and severity of the threats arising within their borders. Threats Identified by Managers at the Eight Parks We Reviewed

At the eight parks studied, the managers identified 127 internal threats that directly affected natural and cultural resources. Most of these threats fell into one of five broad categories: the impact of private inholdings or commercial development within the parks, the results of encroachment by nonnative wildlife or plants, the damage caused by illegal activities, the adverse effects of normal visits to the parks, and the unintended adverse effects of the agency’s or park managers’ actions (see fig. 1). Overall, the park managers we visited said that the most serious threats facing the parks were shortages in staffing, funding, and resource knowledge. 3). 5). Threats Have Damaged Cultural Resources More Permanently Than Natural Resources

Park managers estimated that about 82 percent of the direct threats they identified in the eight parks we reviewed have caused more than minor damage to the parks’ resources. 6 and 7.) Scientific research will generally provide more concrete evidence identifying the number and types of threats, the types and relative severity of damage, and any trends in the severity of the threat. They believed that about 61 percent of the threats had worsened during the past decade, 27 percent were about the same, and only 11 percent had grown less severe (see fig. At Arches National Park, actions ranged from taking steps to remediate some threats to studying how to deal with others. Without systemwide data on these threats to the parks’ resources, the Park Service is not fully equipped to meet its mission of preserving and protecting these resources.
Why GAO Did This Study

Pursuant to a congressional request, GAO reviewed internal threats to the national parks' resources, focusing on the: (1) National Park Service's (NPS) information on the number and types of internal threats; (2) damage these threats have caused; (3) change in the severity of these threats over the past decade; and (4) NPS actions to mitigate these threats.

What GAO Found

GAO found that: (1) because NPS does not have a national inventory of internal threats to the park system, it is not fully equipped to meet its mission of preserving and protecting park resources; (2) park managers at the eight parks studied have identified 127 internal threats to their parks' natural and cultural resources; (3) most of these threats are due to the impact of private inholdings or commercial development within the parks, the impact of nonnative wildlife or plants, damage caused by illegal activities, increased visitation, and unintended adverse effects of management actions; (4) park managers believe the parks' most serious threats are caused by shortages in staffing, funding, and resource knowledge; (5) 82 percent of the internal threats have already caused more than minor damage, and cultural or archeological resources have suffered more permanent damage than natural resources in many parks; (6) 61 percent of internal threats, particularly those from increased visitation and serious fires, have worsened over the past decade, 27 percent have stayed about the same, and 11 percent have diminished; (7) park managers lack baseline data needed to judge trends in the severity of internal threats; and (8) some parks are closing trails to reduce erosion, installing more rugged equipment to reduce vandalism, revoking uncooperative operators' permits, and posting signs to inform visitors of the damage from their inappropriate activities.