Ocean Watch

Monday, July 15, 1996

Big demand for opihi means
few can be found

A recent ad in the newspaper said, "Fresh, frozen opihi from Big Island. $189/gallon."

Wow! Where did anyone get so many opihi? Whenever I see them, they're either too small to harvest or they're stuck to break-neck rocks in pounding surf.

Only once did I see large opihi in accessible abundance, and that was at La Perouse Pinnacles in French Frigate Shoals. This atoll in Hawaii's northwest chain is part of a national wildlife refuge.

"These fat opihi are driving me crazy," my snorkeling partner said after we spotted the big snails with the pointy shells crowded along the pinnacles. "Do you think it's OK to eat just one or two?"

"Better ask the refuge manager," I said.

"Sorry," the manager told him a moment later. "Animals are protected here."

"Even opihi?"

"Even opihi."

My friend, who relishes every kind of seafood imaginable, was disappointed, but certainly saw the point. The no-harvesting rule was, after all, the reason the opihi were ample here in the first place.

OPIHI are snails that live on wave-swept rocks in intertidal and shallow-water areas. Also called limpets, opihi shells resemble Chinese straw hats. Such broad-based shells offer minimum water resistance to the powerful blasts of water that come regularly from breaking waves.

The strong opihi shells also protect the animal when clamped down on its rock home. And these snails can really hang on tight. Unless you sneak up on these critters when they're relaxed, there's little hope of prying them off with bare hands. One local T-shirt says it all: "SUMO OPIHI - Takes a licking and keeps on sticking."

Those people who know how to pick opihi, however, get an instant treat. Many eat these snails raw, popping the meat into their mouths right at the beach. Because of this, it's common to see pearly opihi shells lying empty around rocky beaches.

Opihi have been a popular food source in Hawaii for centuries, mostly on windward sides of the islands. (The shells also made useful tools.) Ancient refuse heaps show that opihi made up about 46 percent of the shell composition at windward sites. Leeward sites showed about 5 percent opihi.

Opihi are more abundant on windward coasts because the snails eat the limu (seaweed) that grows on wave-washed rocks.

Although limpets grow throughout the world, Hawaii's opihi species are only found here. We have four kinds but only two are commonly eaten: the yellow foot (alina'alina) and the black foot (maka'ia'uli). Because the black foot is found higher on the shoreline than the yellow foot, it was traditionally called the lazy man's opihi.

OPIHI are capable of spawning throughout the year, but most often release eggs and sperm into the water from November to June, when seawater is the coolest. After a few days in the ocean, the baby opihi find and stick to a home rock. The snails spend their entire lives, about a year, grazing that particular area.

Compared with the growth rates of limpets in other parts of the world, opihi grow extremely rapidly. The snails reach sexual maturity when the shell diameter is just under an inch, usually after a few months.

The body weight continues to increase throughout the animal's life. The longer an opihi is allowed to grow, the greater the weight of its edible meat.

Opihi picking season is year round. Shells must be at least 11/4 inches wide, or the meat a half inch wide, to legally harvest them in Hawaii. Unfortunately, too few people have followed this rule, making opihi relatively scarce today.

Those that are left are usually found in dangerous, hard-to-reach places. Falling and drowning deaths of opihi pickers are all too common in Hawaii news.