WASHINGTON - Yellowstone, Glacier, Grand Teton and the rest of the parks managed by the National Park Service are woefully understaffed, according to a report released on Tuesday by the National Parks Conservation Association.

Park Service officials said the situation depicted in the report is fundamentally accurate.

The report said the lack of personnel is responsible for everything from limiting the number of students who can participate in ranger-led programs in Yellowstone to undermining the management of threatened and endangered species in Grand Teton to increased poaching in Glacier.

"We're crossing the line and in some parks, visitors will see the impact of the budget situation," agency spokesman David Barna said.

The report blamed the lack of staff on "chronic underfunding." When adjusted for inflation, the National Park Service's budget has decreased by 20 percent during the past 25 years, according to the report. The Bush administration has proposed increasing the NPS budget from $2.3 billion this year to $2.4 billion in fiscal year 2005. The report calls for Congress to provide an additional $240 million. It also calls for the park service to receive $50 million from the Homeland Security Department to cover terrorist threat related expenses.

The report says that only six percent of Yellowstone's 2.8 million visitors are able to participate in ranger-led activities.

Yellowstone officials said they could use more staff, but added that it is not a crisis situation.

"Certainly Yellowstone has some positions that are vacant," park spokeswoman Cheryl Matthews said. "Any superintendent in the National Park Service would tell you he or she could use more money."

National Parks Conservation Association Northern Rockies Office senior director Tony Jewett said lawmakers had stepped in to address emergencies in the three parks, which are often referred to as among the "crown jewels" of the system. Nevertheless, Jewett said overall the situation in the three parks was the same as the situation in the rest of the system.

"It's right in line with the levels that are endemic to the whole system," Jewett said. "Dealing with emergencies does not eliminate the endemic problems. We shouldn't be funding parks based on what today's crisis is. We need to be preserving them for future generations."

The report notes the number people visiting Yellowstone has increased by 50 percent since 1980, while the amount of money the park has received has only increased 4.8 percent before being adjusted for inflation and 1.4 percent after being adjusted for inflation.

Yellowstone officials completed a business plan last year that determined the park needed $22.7 million more each year.

"That's pretty much in line with other parks that have done business plans," Matthews said.

Jewett noted that although Yellowstone, Grand Teton and Glacier would receive funding increases under the Bush administration's 2005 budget proposal, the money would not be directed toward increasing the number of rangers who interact with visitors.

Yellowstone is receiving $28.1 million this year and would receive $29.1 million under the Bush administration's proposal for the Interior Department in fiscal year 2005. The $950,000 increase that the park would receive under the proposed budget would be focused on protecting and maintaining the park's roads.

"Deferred maintenance has led to the virtual failure of some of Yellowstone's roads," according to a department budget document.

Grand Teton is receiving $9.4 million this year and would receive $9.9 million under the Bush administration's proposal for the Interior Department in fiscal year 2005. The $550,000 increase that the park is scheduled to receive under the proposal would go toward implementing a winter use plan and operating a historic preservation training and technology center.

Jewett credited Senators Conrad Burns, R-Mont., and Craig Thomas, R-Wyo., for fighting for more money for the parks, but said they had often been stymied by fellow lawmakers. Burns is chairman of the panel that has jurisdiction over the park services budget and Thomas is chairman of the panel that has jurisdiction over park service policy.

Burns and Thomas said they planned to continue their efforts to increase funding for the parks.