Islands’ opihi slipping from shellfish lovers’ grasp : No luau is complete without it. But it costs almost $200 a gallon.

Palikapu Dedman stalks across the slick lava rock, crouches for a moment, then pounces on his prey with one quick swipe of his stainless-steel butter knife.

“You have to make it a good shot the first time,” said the burly Hawaiian, explaining a tradition more than 1,000 years old, “(otherwise) there’s no space between the shell and the rock to let your knife through.”

Dedman, 44, is one of a declining number of hardy souls willing to risk their lives in pursuit of the lowly opihi, Hawaii’s answer to the abalone. A small, cone-shaped shellfish, opihi (pronounced oh-pee-hee ) cling to rocks lashed by the ocean.

The early Hawaiians dubbed opihi “the fish of death” because so many people were swept away while prying them off the rocks.

Among the most primitive of gastropods, opihi are responsible for more marine deaths in Hawaii than sharks or any other animal, state authorities say. While their human predators scramble, the limpets clamp onto their precarious perches with a suction of up to 70 pounds per square inch.

Even with this fearsome batting average against people, however, the outlook for opihi is bleak. Some devotees fear the delicacy may vanish from the local diet, and with it a slice of culture that has been cherished since the first Polynesians arrived on these shores.

A species of limpet unique to Hawaii, opihi once thrived here. Early Hawaiians feasted on them and used the shells as scrapers for peeling taro and as jewelry. Nowadays, shores close to populated areas have been raked clean and hunters must venture onto ever more remote and dangerous terrain to find opihi.

For newcomers to the islands, the salty, yellow-and-gray morsels are, at best, an acquired taste. Tourists turn up their noses at this Hawaiian version of escargot, served raw and, sometimes, still alive and kicking. For locals, nothing quite compares. Purists eat them straight from the shell, wiggling tentacles and beady eyes notwithstanding.

“It’s a unique taste, slightly rubbery but crunchy,” explained fishmonger Guy Tamashiro, who fancies the “nice juicy live ones. . . . It’s like a baby abalone, but you eat the guts too--they add flavor.”

Although limpets are eaten elsewhere, nowhere else are they relished with the gusto shown by Hawaiians, according to E. Alison Kay, a University of Hawaii zoologist and opihi expert. Local legend touts opihi as a food fit for the gods. The volcano goddess, Pele, reputedly enjoyed munching on them while waiting to catch waves.

No luau is considered to be complete without this protein-packed appetizer, but only the richest host can afford to serve them. Opihi are doled out in paper cups barely bigger than a thimble. So rare are they that they fetch nearly $200 a gallon, shucked.

Chuck Machado, owner of a luau supply company, did the unthinkable a few years ago and stopped carrying opihi. “It gave me too much stress worrying whether it would show up or not,” he confessed. “It’s unbelievable, the scarcity.”

At the turn of the century, local markets handled about 150,000 pounds of opihi a year. Today, less than 10,000 pounds are sold annually. Although the opihi is not in danger of extinction, its decline has attracted some attention.

As early as 1951, legislator Hiram Fong tried to come to the opihi’s rescue. But other officials were less responsive to their mute marine constituents, and it wasn’t until 1978 that the state forbade the taking of any opihi smaller than 1.25 inches.

The regulation, however, seems to be widely ignored, according to zoologist Kay, who has studied shell remains at popular gathering spots. “What’s needed,” she said, “is self-control.” She suggested observing a closed season, to give the limpets some “breathing space.” Dedman and marine botanist William Magruder of Bishop Museum would like to see commercial harvesting banned.

A state-sponsored study showed a decade ago that opihi could be cultured, and there has been talk of ranching them, but the money has not materialized. To opihi devotees, prospects are depressing.

“We’re losing something unique to these islands,” Dedman said with a sigh. “I was raised to find food on a rock, and now, not seeing it any more--it’s a real scary feeling.”