DENVER — The elk population that roams and sometimes rampages through the delicate landscape of Rocky Mountain National Park is out of control and will be reduced through a program that will use sharpshooters to cull the herd, park officials said last week.

The plan, which is expected to receive final approval by the National Park Service in January, would involve killing up to 200 of the animals each year, beginning in 2009.

The herd, believed to be descended from a tiny transplant community brought down from Wyoming during World War I, has become a major tourist attraction — and a severe problem for park managers. The animals, which can weigh up to 700 pounds for a full-grown bull, feed on fragile aspen and willow stands. In some places the stands have been devastated by the herd's growing numbers.

Rocky Mountain National Park is one of the most heavily used national parks. And the majestic, slow-moving elk, numbering upward of 3,000 in some years, have become one of the park's signature photo opportunities, even as their environmental impact has grown. Park officials say a sustainable population is about 1,600 to 2,100 animals.

But arriving at a population-control solution has been a messy process. Public hearings last year about proposed alternatives, including reintroducing wolves and reintroducing hunting by humans, were fractious and divisive.

A park biologist who led a management study of the elk, Therese Johnson, said that even with the plan in place, it was still uncertain how many animals might have to be killed in any year.

Johnson said that for several reasons, the park's elk population had recently fallen a bit. About 700 were killed by hunters outside the park last year, one of the highest numbers in years. And more of the animals appear to be spending time in forest areas outside park boundaries.

She said that if the trend continued, there might be years when no animals needed to be killed. She also emphasized that the culling program would be scientifically based. The shooting would be done in winter, she said, when there are few visitors, with a goal of mimicking as much as possible how natural predators like wolves would reduce a herd, by taking out the old, the weak and the ill.

"We're going to be as efficient as possible," Johnson said. "This will not be anything like hunting."