State lawmakers are considering banning the sale of 'opihi for 15 years as a way to protect and conserve the edible Hawaiian limpets.

The House Water, Land and Ocean Resources and Hawaiian Affairs Committee on Monday advanced a bill that would set a moratorium on selling or offering to sell 'opihi for 15 years. The measure now faces review by the House Judiciary Committee.

Proponents of the bill said 'opihi has been overharvested and that a ban on its sale would help preserve and grow its populations in Hawai'i.

But opponents said a moratorium is unnecessary and that a ban would create a black market for the local delicacy.

The measure, originally drafted as a permanent ban, resurfaced after stalling last session and follows a previous attempt to prohibit the sale of 'opihi. Gov. Linda Lingle in 2006 vetoed a bill to enact a permanent ban, citing concerns that it would be difficult to enforce and that it would result in a black market for 'opihi.

Under the current measure, Senate Bill 6, the taking of more than a half-gallon of 'opihi per person per day is presumed to be for the purpose of selling. The sale of 'opihi shells at least 1.25 inches in diameter for jewelry would be exempt from the ban.

State fishing regulations permit the collecting of limpets year-round so long as their shell diameter is at least 1.25 inches or the diameter of the meat is a half-inch.

Sierra Club Hawai'i Chapter director Jeff Mikulina said a moratorium would benefit Hawai'i's 'opihi stocks and that anecdotal evidence indicates that the populations are hurting.

"It gives some breathing room for the species," Mikulina said. "Their increased popularity has put a lot of pressure on the population."

But companies such as Yama's Fish Market and Tamashiro Market said 'opihi is not in short supply and that a better alternative is proper resource management.

Brian Yamamoto, president of Yama's Fish Market, said his pickers have told him there are lots of 'opihi available and that there's a lack of 'opihi pickers. He suggested other ways to conserve 'opihi, such as establishing no-take areas.

"They say (under the bill) you can pick it for your own consumption, but how many guys know how to pick 'opihi or even want to?" he said.

Chris Bird, a marine ecologist at the Hawai'i Institute of Marine Biology, said commercial harvest numbers on 'opihi — the only statewide statistics available to measure the size of 'opihi populations — show a decline from about 16,000 pounds harvested annually in 1970 to about 8,100 pounds a year now. The "exponentially" increasing price of 'opihi also indicates a decline in the number of 'opihi, he said.

Bird said no species of 'opihi in Hawai'i is at risk of becoming endangered. But, he said, "we believe that the fishery could be healthier and we believe that the population of 'opihi could be much more abundant if they were managed in a different way." Establishing no-harvest areas is promising, and regulations need to take into consideration the characteristics of all three species of 'opihi in Hawai'i, he said.

He said a ban on the sale of 'opihi would present a "catch-22" because it would eliminate data. A ban should be accompanied by a system to monitor the population size in order to determine the effectiveness of a prohibition, he said.

Francis Oishi, recreational fisheries program manager with the Department of Land and Natural Resources, said the department is in the process of drafting rules for more stringent regulations to better protect 'opihi and is considering measures including bag limits and increasing the minimum size of 'opihi people can take. The proposed rules are scheduled to be presented to the public for input this year, he said.

He said the department is not currently considering banning the sale of 'opihi.

Reach Lynda Arakawa at larakawa@honoluluadvertiser.com.