NAZCA, Peru -- Emerging like a mirage in Peru's coastal desert, the massive figures of a hummingbird, monkey, lizard and other shapes carved into a rocky plain have baffled archaeologists for decades, surrendering only the faintest clues about their ancient purpose.

But the enigmatic Nazca Lines now appear to be sending one signal loud and clear: SOS! (Save Our Symbols!)

After years in which the Lines suffered gradual destruction, a new tide of tomb raiders seeking pre-Inca artifacts is scarring the terrain with hundreds of burrows amid the figures here, and near even older shapes around the neighboring town of Palpa. A boom in copper and gold mining -- including a mine built four years ago a few feet from a 2,000-year-old, two-mile-long trapezoid -- is defacing parts of the Lines with tracks from truck traffic.

Over the past decade, advertisers and political campaigns have carved huge messages in the rock and sand between the ancient designs in this region 250 miles south of Lima. In 1998, floods and mudslides from the El Nino weather pattern seriously eroded several figures. And as electricity reaches the growing local population, utility companies are running power cables over and around the site. Earlier this month, contractors were digging deep holes for a power post six feet from a spiral in high relief.

The damage to the Lines underscores Peru's desperate struggle to preserve its national patrimony. Archaeologists say they are watching helplessly as the quest for scholarship and conservation in a country viewed as the cradle of New World civilization is losing out to commercial interests, bleak poverty and the growing popularity of heritage sites as tourist attractions.

"Our cultural heritage is in jeopardy, and it is not just Peru that stands to suffer," said Alberto Urbano, regional director of Peru's National Institute of Culture. "If we do not act quickly to preserve these sites, the world may lose out on an opportunity to understand some of the earliest known and greatest secrets of ancient human civilization."

The difficulties extend beyond Nazca. Last September, a beer company with a permit to film a commercial in Machu Picchu, the 500-year-old "lost city of the Incas" nestled in the Andes, accidentally dropped a camera crane and damaged the site's stone solar calendar. Two weeks ago, a skull estimated to be 4,500 years old was stolen from Peruvian archaeologists excavating ruins near Caral, a town 120 miles north of Lima. A study published last month dated the ruins to 2,600 B.C., making it the oldest known city in the Americas, thriving around the same time the pyramids were built in Egypt.

Archaeologists say Peru lacks funds not only to protect important sites, but also to research them -- a problem shared by much of the developing world, including archaeologically rich Latin America.

"There has been an enormous lack of political will in Peru to do anything but exploit sites for their tourist value," said Ruth Shady, an archaeologist at the San Marcos National University in Lima. Shady's research uncovered the importance of the Caral ruins, which revised the date for the birth of high civilization in the New World 1,500 years earlier than previously believed. "And even though international scientists have talked about the importance of early cultures and important sites in Peru, they have done little to help us secure funds from abroad to protect and study them."

The damage to some sites is cumulative, coming from years of neglect. The Pan American Highway, for instance, was constructed through the tail-of-the-lizard figure back in the 1940s. But experts here say that pressure over the past decade has been disturbingly intense.

The Nazca Lines, first seen in their entirety during overflights in the 1930s, are a wonder of early architecture and structural design. They cover nearly 400 square miles of desert with startlingly precise geometrical figures, including miles-long animal shapes and trapezoids.

In Nazca, a poverty-stricken city of 30,000, tourism has tripled to 70,000 foreign visitors a year since 1995. Today, it is not uncommon for the small tourist planes flying over the region to spot wayward foreigners trudging over the Lines, which can be fully seen only from the air.

The area, home to a series of major cultures over almost two dozen centuries, is policed by two officials from the National Institute of Culture who share a bicycle to patrol the vast zone, located in one of the driest deserts on Earth. "When I look at the problems we face and the lack of funds to combat them, I feel like a grain of sand on a beach being covered by a wave," Urbano said.

One of the most troubling problems has been the surge in tomb-looting. Typically scavenging the sands at night with steel poles used to detect hidden tombs or buried ceramics, the raiders have become bold. This month, a pair of thieves could be spotted from the air in broad daylight tearing open a tomb near the citadel of Cahuachi, a structure that dates to the 2,000-year-old Nazca culture that is believed to have constructed the Lines.

A recession and record unemployment have led some residents to become professional relic scavengers. Only a portion of the wealth hidden in tombs across the coastal desert has been discovered. One piece of ancient pottery can fetch $50, more than a month's salary for day laborers, from black-market dealers who then sell the pieces for several times that price to Peruvian or foreign collectors.

Prized textiles and gold ornaments sell for much more, often fetching tens of thousands to hundreds of thousands of dollars on the international market. While it is against Peruvian law to remove pre-Columbian artifacts from the country, "artifact mafias" run by American, Italian and Swiss dealers have become expert in spiriting out objects, officials say.

The destruction of the Nazca Lines has started to worry tourism companies that make a living off them. Next month, Aero Condor, the Lima-based airline offering the largest number of tourist flights over the Lines, will launch the Nazca Patrol, a partnership with local police to track and catch tomb raiders with the aid of a newly purchased ultralight aircraft.

"That's what we have to stop!" shouted Eduardo Herran, a pilot and the coordinator of the Nazca Patrol, as he pointed at two men with shovels jumping for cover into a dug-up tomb during a low overflight of the Lines. "They have become so audacious that sometimes they don't even try to hide."

Peruvian archaeologists say that as frustrating as the looting is, an even greater challenge is the lack of funding that prevents them from performing the work that would unlock answers to vital questions about the earliest periods of human civilization in the New World.

On a windy afternoon recently at the Caral ruins, two Peruvian archaeologists earning $2.40 a day toiled under the desert sun. Although archaeologists have worked here continually for the past four years, less than 5 percent of the site has been explored. Without equipment, workers, chemists or engineers, most of the massive pyramids, temples and houses remain covered with rock and sand.

"And that's probably the way they will stay for a long time," said Rudy Peralta, one of the two archaeologists digging here with the help of a day laborer. "Science is working against the odds in Peru."

The mudslides, which followed hard rains caused by the weather phenomenon El Niño, damaged several lines and one of the Nazca triangles and could threaten more serious damage, said Nazca historian Jose Lancho.

The avalanches in recent days have spared the well-known figures of a monkey, lizard, a spider and other animals made by the
Nazca Indians between 300-600 A.D., said Nazca historian Jose Lancho. The figures are among Peru's main tourist attractions.

But Lancho said that these and hundreds of other lines and figures could be damaged if El Niño's rains continue.

The lines are shrouded in mystery and there are several theories about their purpose. One holds that the lines are a giant
astronomical map that told ancient desert dwellers when to plant and irrigate their crops.

El Niño has brought heavy rains to Peru's bone-dry southern desert, causing massive flooding and mudslides. The nearby city of Ica was devastated last week by a flood that swamped 90 percent of the city, washing away adobe houses and leaving thousands homeless.

© Copyright 1998 The Associated Press