White Abalone

Loved to Death

The large, flat shells of living abalone once carpeted the rocky waters along California’s coastline from Mexico to Oregon. Prior to European settlement, Native Americans feasted on the mollusk’s muscular foot and employed its shell as a colorful decoration. More recently, Californians have established a multi-million dollar industry harvesting abalone and delivering the tasty treat to the salivating mouths of seafood connoisseurs.

Abalone’s popularity has also spelled its doom. Populations have collapsed between San Francisco and the Mexican border, where intense commercial and recreational harvesting has gone unregulated for over a century. Two of North America’s five commercially viable abalone species may become the first marine invertebrates listed under the federal Endangered Species Act. And our most economically valuable species, the white abalone, could become the first marine invertebrate driven to extinction by humans.

As recently as the 1970s, white abalone still flourished off the coast of Southern California, even as other species of abalone were in sharp decline. Commercial landings during that time were recorded in tons of white abalone per year. By the late 1980s, however, yearly harvests were averaging 10 pounds, and in 1992 and 1993 commercial harvesting efforts yielded no white abalone at all. Yet lawmakers continued to allow commercial harvesting of white abalone until 1996, when conservationists petitioned the state government for an emergency closure of Southern California’s abalone fishery.

Today, much of the hope to save the white abalone rests on the success of a captive-breeding program, a measure never before used to restore an invertebrate species. Confounding the odds for success of this program has been the fact that, until last October, officials had only one white abalone in captivity, a male. That month, marine biologists with the California Department of Fish and Game (DFG) searched for a female mate during a two-week submarine-aided abalone investigation.

DFG biologist Kon Karpov explains the results of that search. “In 125 miles of prime habitat, we found only 157 white abalone,” says DFG biologist Kon Karpov. “However, since we found no juveniles, and only two pair in close enough proximity to breed, it’s possible that these abalone are no longer reproducing, that they’re simply ‘living fossils’.” Karpov adds that although a suitable female mate was collected, trying to restore an entire population from just one pair is not a possibility. “Too much genetic information would be lost if you tried to restore the species from just two animals,” he says. “Instead we’re using these abalone to improve breeding methods while we search for more individuals.”