OLYMPIC NATIONAL PARK — Campers off Deer Park Road, which opened for the season Saturday, may be disturbed by early-morning helicopter landings and takeoffs as the mountain goat census is completed.

The road southeast of Port Angeles opened after Olympic National Park crews cleared snowdrifts and large rocks off the road and graded it.

The upper road, which leads to the trailhead, also has been graded, but motorists are urged to use caution as this section of road may still be slippery because of the moisture that has soaked into it, said Barb Maynes, park spokeswoman.

Helicopters used in a mountain goat census that began Monday operate from a landing area at Deer Park and may awaken campers or cause traffic delays through Tuesday, Maynes said.

The helicopters fly between 5:30 a.m. and 11 a.m.

The goat census in the park and Olympic National Forest, conducted in conjunction with the U.S. Geological Survey, is the first such count of the animals since 2004, when the population was estimated to be between 259 and 320.

It is funded with a $40,000 National Park Service grant.

The census is essential, said park wildlife biologist Patti Happe, to manage a goat population that can be so aggressive that the park earlier this month issued strict guidelines for human-goat interaction and for how the park deals with overly intrusive goats that are seen as potentially dangerous.

A mountain goat fatally gored Bob Boardman of Port Angeles on Switchback Trail near Klahhane Ridge on Oct. 16.

The park’s revised 2011 Goat Action Management Plan includes advice for hikers to stay at least 50 yards from all mountain goats and to urinate 200 feet from trails to avoid attracting the animals, which are drawn to the waste and can become aggressive when territorial.

Preliminary census results will be released in August, the park has said.