Shells are the true gems of the ocean and a beachcomber's most prized find. Although, commonly used today to adorn necklaces, earrings and bracelets, or to decorate the home, shells and their inhabitants lead full lives below the sea and once served more practical purposes when picked from the beach environment.
Cowries, or leho in Hawaiian, are one of the most widely collected sea shells. Of the 200 known variations of cowries in the world, 35 come from Hawaii; nine of these exist nowhere else in the world.
Cowries hide beneath coral or in cracks and crevices during the day and only come out at night. Many cowries are herbivores, while others dine on sponges and other animals. They generally mate for life and remain in one area for their entire lives. Once fertilized, the female cowrie will lay her eggs on the ocean floor and sit on them like a nesting bird for up to four weeks. The eggs hatch into drifting veligers (planktonic larvae) that eventually settle to the bottom and become juveniles. Gradually, they develop shells that wrap completely around their soft bodies.
Tiger cowries have mantles that are dark gray and mottled with pointed white-tipped papillae, while other cowries may have red, yellow or black base colors, combined with a some variation of papillae colors.
The most easily recognizable cowrie is the tiger cowrie (Cypraea tigris). A tiger cowrie's shell doesn't look much like a seashell at all. Seashells are usually shaped like caps, as the limpets are, or they are coiled. The cowrie shell appears to be neither. It's much too glossy, and it's shaped like an egg with a toothed, slitlike opening common only to cowries.
Most popularly known for its outer appearance, the animal inside is every bit as noteworthy. Unlike other shell-bearing mollusks, the cowrie possesses a mantle, or coating, that it can spread over its outer shell to protect it. This smooth, glossy finish is distinctive of all cowries. The tiger cowrie's mantle is dark gray and mottled with small, pointy, white-tipped projections of tissue.
In old Hawaii, tiger cowrie shells were used for lures. Only the shells with the perfect color could tempt the discriminating he'e, or octopus. Lawai'a, or fishermen, would carefully match a stone sinker with a cowrie shell lure. Some shells were first smoked over a fire to achieve the coloration considered ideal for fishing at a particular time of day or evening. Together, with a bone hook, these items were lashed to a wooden shaft with triple-stranded cordage and used as a fishing device.
Successful lures, as well as the skill of fishing for octopus with a cowrie was passed down from one generation to another. A favorite lure may have been named after a beloved relative or ancestor. Stories and chants memorialized lures that possessed special powers to attract octopus or squid. The most famous were said to be so irresistible to their intended prey that they only had to be dangled to the side of a canoe and "squids came climbing in."
Appreciated for their shine and pattern variations, cowries are gathered as keepsakes or sale by many beach combers and ocean lovers. So prized are some shells that they could face the risk of extinction.
When walking the beach or exploring the reef, resist the temptation to remove shells from their habitat. And if the surf dumps a seashell at your feet, put it back where it belongs. The original owner might still be living in it. Also remember that vacant shells can sometime be adopted by other small animals that will move in and reuse the shell as a new home.
* Lori Mellenbruch is the director of sales and marketing at the Maui Ocean Center. "Ka Mo'olelo Moana," or "The Ocean Story," is a monthly column submitted by center staff members. The center is open from 9 a.m. to 5 p.m. daily in Maalaea. For more information, call 270-7000.