Visitors to Hawai'i Volcanoes National Park have been leaving incense, coins, bottled water, fruit, rice and other edibles at the rim of the volcano crater, and park officials are trying to put a stop to the practice.

Tourists and other visitors may think they honor the volcano goddess Pele with the objects they leave behind, but park rangers say the food and other rubbish abandoned at the rim of Halema'uma'u Crater attract rats and roaches, and can be fatal to the endangered nene geese that live in the park.

Park crews now haul off about 45 pounds of food and other objects each week. Park officials avoid calling the leavings "offerings" so as not to confuse them with religious practices of Native Hawaiians, which are protected under federal law.

Many Native Hawaiians consider Kilauea's summit area sacred land, but parks officials believe "very few" of the items left on the crater rim are traditional Hawaiian religious offerings.

Some Hawaiian elders have complained about the mess at the crater, and one hula halau that visited the crater during the Merrie Monarch festival this year became so disgusted at the objects littering the area that halau members launched their own impromptu cleanup, said national park archaeologist Jade Nakamura.

Nakamura said she believes that many of the objects are left on impulse by some of the more than 1.5 million visitors to the park each year. Parks officials also believe visitors tend to copy what they see, with one visitor leaving an apple, for example, and the next leaving an orange.

The abandoned food attracts the nene, which can sicken and die from eating the raw rice, beans, fruit, meat and other food. It also encourages the geese to look for handouts in parking lots and by the road, where they are run over by cars.

Both littering and feeding wildlife is prohibited within national parks, parks officials said.

Also left behind are candles, crystals, flowers and other objects. Anything paper or Styrofoam is quickly airborne, and "that's part of the problem, too," Nakamura said.

"They'll put it in a spot, and because it's so windy up there it just blows, and then it will blow into the cracks, and then we're forced to go into the crack and clean it out," she said.

To address the problem, parks officials staged a cleanup at the crater Saturday with help from volunteers from Expedia and the Big Island visitor industry. They collected a pickup-truck-sized load of trash.

Parks officials also launched a Leave No Trace campaign.

The campaign will use handouts, bookmarks and signs to remind visitors and tour operators to pick up after themselves, to protect the park's natural beauty and to respect Hawaiian culture.

The effort will also include temporary exhibits at Kilauea Visitor Center and Jaggar Museum to underscore the problem.

"We look to our partners and local communities to assist us in communicating the value of resource protection and cultural sensitivity," said park superintendent Cindy Orlando in a written statement. "With public support, we are confident that we can stop the proliferation of litter. Islandwide, we are all in this together."

Reach Kevin Dayton at kdayton@honoluluadvertiser.com.