National Geographic : 1972 Aug
four feet below the surface. Cutting any lower might endanger the plants' reproductivity. The wet kelp is taken ashore, ground, and chemically processed to extract the algin, which emerges as a dry powder. The size of the kelp industry is best indicated by the fact that 155,560 wet tons were harvested last year off California. Algin is not the only thing of value found in the underwater forests. The luxurious growth attracts rockfish, perch, croaker, and kelp bass. Such sought-after shellfish as the California spiny lobster, abalone, and rock scallop abound there. Kelp thus benefits both sport and commercial fishermen. Adding together all uses of California's kelp beds, I would estimate their worth at tens of millions of dollars a year-perhaps a million dollars for each of the nearly 90 square miles of kelp forests surviving in state waters. Diving Scientist Takes a New Job Two decades ago a few people began to suspect that the giant kelp beds were dwin dling. There was no alarm at first, because kelp has good years and bad. But it finally became apparent that the kelp was indeed in serious trouble. Deterioration had already halted harvesting in the once-lovely forests fringing the rugged shoreline along the Palos Verdes Hills south of Los Angeles; off San Diego the Point Loma bed, which during World War I yielded an average of 75,000 tons of kelp a year, had all but disappeared. There was no agreement as to why the seaweed was vanishing. Some thought over cutting was the cause; others blamed pollu tion. An extensive underwater study might clear up the mystery-but it would require a scientist who could dive. In those days, when most marine biologists were still wading around in tidal pools, I had learned to dive to collect sea anemones for experiments I was then conducting at the Scripps Institution of Oceanography in La Jolla, California. But sea anemones and kelp ecology obviously are not closely related, so I was a bit surprised when Professor Charles D. Wheelock, Director of the University of California's Institute of Marine Resources in San Diego, said to me one day: "Wheeler, you're the right man for the kelp study. How about taking it on?" True, I had the basic qualifications-an advanced degree and diving experience. I knew from personal observation that several once-flourishing kelp forests were on the 256 Unlikely partners TOOTHY MAW of a kelp-dwelling moray eel signals a meal to "clean er" shrimp surrounding it (above). The shrimp troop over the gaping beast, gleaning tiny parasites from its skin. Sated, the cleaners soon left, but their mottled host opened wide again, apparently dissatisfied with the once over. Its friends returned to their job with renewed vigor (right), unafraid despite the moray's penchant for eat ing its benefactors.