SAGUARO NATIONAL PARK, Arizona - When Steve Bolyard checked on a report of black paint on some of the park's majestic saguaros - cactuses whose towering bodies and upraised arms are emblematic of the American West - he did not expect to see graffiti covering more of them than he could easily count.

"It was too much," said Mr. Bolyard, a park ranger. Eventually, rangers found at least 45 graffiti tags in the park, including 16 on the slow-growing saguaro.

It was the latest example of a trend that has been unnerving park officials from Rocky Mountain National Park in Colorado to Arches in Utah and Joshua Tree in California. The wilder side of urban life - vandalism, graffiti and litter - has found its way into the wilderness.

The cause of this recent spike in graffiti on public lands is unclear, but some park personnel say there is reason to believe that it coincides with the rise of social media. "In the old days," said Lorna Lange, the spokeswoman for Joshua Tree, "people would paint something on a rock - it wouldn't be till someone else came along that someone would report it and anybody would know about it."

She added, "with social media people take pictures of what they've done or what they've seen. It's much more instantaneous."

And that instant gratification could stimulate the impulse to deface.

While there has been graffiti in national parks since before they were parks, with covered wagon pioneers carving their names into cliffsides as they made their way west, this is something new, park officials say. Vandals have spray painted over ancient petroglyphs and painted boasts on famous rock formations. They have chopped up precious plant specimens, knocked down stalactites and dumped just about anything imaginable beside streams.

Gannon Frain, 28, a frequent visitor to Western parks, has been accumulating photos documenting the destruction. "A lot of people just think they are special - the rules don't apply to them and they've got an inflated sense of self-worth about getting someplace remote," he said.

He added, "It's one thing to see a pioneer's inscription on a wall. It's another to see the signature of the 1,237,000th of 2 million visitors."

Few of the vandals are caught. Cleanup costs run into the hundreds of thousands of dollars. "When budgets are this tight," said Andy L. Fisher, the chief of interpretation and outreach at Saguaro, "it's not like we have a slush fund to go and clean up vandalism. Dealing with this means we're not doing something else."

Not all the graffitists get away. At El Morro National Monument in New Mexico in 2011, two South Korean exchange students added their own contributions to Inscription Rock, a treasured panel where 19th-century soldiers and pioneers etched their names. One wrote "Super Duper Dana," the other, "Gabriel." Rangers later checked the visitor sign-in book and saw the name "Dana Choi" followed by "Super Duper Dana Choi." Ms. Choi and another student, Seung Hoon Oh, later posted pictures of their trip on their Facebook pages. When contacted by park officials, they admitted their acts, eventually pleading guilty to violation of a federal law protecting archaeological resources. They were fined nearly $15,000 each.

When vandals at Saguaro chopped up cactuses, rangers retrieved photos of two men taken by a wildlife camera. The pictures were broadcast on news stations in Tucson and published on newspaper Web sites. The next day, Beau Campbell and Colton Salazar turned themselves in. They have been charged with violations of federal regulations protecting park resources, according to Ms. Fisher.

"Tucson loves its Saguaro forests," said Kevin Dahl, a Tucson-based official of the nonprofit National Parks Conservation Association. "It's much more visceral than if they had thrown a rock through a window. It's like they hurt a family member."

The New York Times

(China Daily 06/23/2013 page9)